[Federal Register Volume 75, Number 208 (Thursday, October 28, 2010)]
[Proposed Rules]
[Pages 66482-66552]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2010-26477]



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Part III





Department of the Interior





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Fish and Wildlife Service



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50 CFR Part 17



 Endangered and Threatened Wildlife and Plants; Endangered Status and 
Designation of Critical Habitat for Spikedace and Loach Minnow; 
Proposed Rule

  Federal Register / Vol. 75 , No. 208 / Thursday, October 28, 2010 / 
Proposed Rules  

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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

[Docket No. FWS-R2-ES-2010-0072; MO 92210-0-0009-B4]
RIN 1018-AX17


Endangered and Threatened Wildlife and Plants; Endangered Status 
and Designation of Critical Habitat for Spikedace and Loach Minnow

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Proposed rule.

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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), propose to 
change the status of spikedace (Meda fulgida) and loach minnow (Tiaroga 
cobitis) from threatened to endangered under the Endangered Species Act 
of 1973, as amended, and to designate critical habitat for both 
species. In total, we are proposing approximately 1,168 kilometers (726 
mi) of streams as critical habitat for spikedace, and 1,141 kilometers 
(709 miles) of streams as critical habitat for loach minnow. The 
proposed critical habitat is located in Apache, Cochise, Gila, Graham, 
Greenlee, Navajo, Pima, Pinal, and Yavapai Counties, Arizona, and 
Catron, Grant, and Hidalgo Counties in New Mexico.

DATES: We will consider comments received or postmarked on or before 
December 27, 2010. We must receive requests for public hearings, in 
writing, at the address shown in the FOR FURTHER INFORMATION CONTACT 
section by December 13, 2010.

ADDRESSES: You may submit comments by one of the following methods:
     Federal eRulemaking Portal: http://www.regulations.gov. 
Follow the instructions for submitting comments to Docket No. FWS-R2-
ES-2010-0072.
     U.S. mail or hand-delivery: Public Comments Processing, 
Attn: [Docket Number FWS-R2-ES-2010-0072]; Division of Policy and 
Directives Management; U.S. Fish and Wildlife Service; 4401 N. Fairfax 
Drive, Suite 222; Arlington, VA 22203.
    We will not accept e-mail or faxes. We will post all comments on 
http://www.regulations.gov. This generally means that we will post any 
personal information you provide us (see the Public Comments section 
below for more information).

FOR FURTHER INFORMATION CONTACT: Steve Spangle, Field Supervisor, U.S. 
Fish and Wildlife Service, Arizona Ecological Services Office, 2321 W. 
Royal Palm Road, Suite 103, Phoenix, AZ 85021; telephone (602) 242-
0210; facsimile (602) 242-2513. If you use a telecommunications device 
for the deaf (TDD), call the Federal Information Relay Service (FIRS) 
at 800-877-8339.

SUPPLEMENTARY INFORMATION:

Public Comments

    This document consists of: (1) A proposed rule to reclassify 
spikedace (Meda fulgida) and loach minnow (Tiaroga cobitis) from 
threatened to endangered status; and (2) a proposed rule to designate 
critical habitat for the two species.
    We intend that any final action resulting from this proposed rule 
will be based on the best scientific and commercial data available and 
be as accurate and as effective as possible. Therefore, we request 
comments or information from other concerned government agencies, the 
scientific community, industry, or any other interested party 
concerning this proposed rule. We particularly seek comments 
concerning:
    (1) The factors that are the basis for making a listing 
determination for a species under section 4(a) of the Endangered 
Species Act of 1973, as amended (Act) (16 U.S.C. 1531 et seq.), which 
are:
    (a) The present or threatened destruction, modification, or 
curtailment of its habitat or range;
    (b) Overutilization for commercial, recreational, scientific, or 
educational
    purposes;
    (c) Disease or predation;
    (d) The inadequacy of existing regulatory mechanisms; or
    (e) Other natural or manmade factors affecting its continued 
existence.
    (2) Additional information concerning the range, distribution, and 
population size of this species, including the locations of any 
additional populations of this species.
    (3) Any information on the biological or ecological requirements of 
the species.
    (4) The reasons why we should or should not designate habitat as 
``critical habitat'' under section 4 of the Endangered Species Act of 
1973, as amended (Act) (16 U.S.C. 1531 et seq.) including whether there 
are threats to the species from human activity, the degree of which can 
be expected to increase due to the designation, and whether that 
increase in threat outweighs the benefit of designation such that the 
designation of critical habitat may not be prudent.
    (5) Specific information on:
     The amount and distribution of spikedace and loach minnow 
habitat;
     What areas occupied at the time of listing and containing 
features essential to the conservation of the species should be 
included in the designation and why;
     Special management considerations or protections that 
features essential to the conservation of spikedace and loach minnow, 
as identified in this proposal, may require, including managing for the 
potential effects of climate change; and
     What areas not occupied at the time of listing are 
essential for the conservation of the species and why.
    (6) Land use designations and current or planned activities in the 
subject areas and their possible impacts on proposed critical habitat.
    (7) Any probable economic, national security, or other impacts of 
designating any area that may be included in the final designation. We 
are particularly interested in any impacts on small entities or 
families, and the benefits of including or excluding areas that exhibit 
these impacts.
    (8) Whether we could improve or modify our approach to designating 
critical habitat in any way to provide for greater public participation 
and understanding, or to better accommodate public concerns and 
comments.
    (9) Information on whether the benefit of an exclusion of any 
particular area outweighs the benefit of inclusion under section 
4(b)(2) of the Act. We specifically solicit the delivery of spikedace- 
and loach minnow-specific management plans for areas included in this 
proposed designation. Management plans considered in previous critical 
habitat exclusions for spikedace and loach minnow are available through 
the contact information listed in the FOR FURTHER INFORMATION CONTACT 
section.
    (10) Information on the projected and reasonably likely impacts of 
climate change on spikedace and loach minnow and on the critical 
habitat areas we are proposing.
    You may submit your comments and materials concerning this proposed 
rule by one of the methods listed in the ADDRESSES section. We will not 
accept comments sent by e-mail or fax or to an address not listed in 
the ADDRESSES section.
    We will post your entire comment--including your personal 
identifying information--on http://www.regulations.gov. If you provide 
personal identifying information, such as your street address, phone 
number, or e-mail address, you may request at the top of your document 
that we withhold this information from public review. However, we 
cannot guarantee that we will be able to do so.

[[Page 66483]]

    Comments and materials we receive, as well as supporting 
documentation we used in preparing this proposed rule, will be 
available for public inspection on http://www.regulations.gov, or by 
appointment, during normal business hours, at the U.S. Fish and 
Wildlife Service, Arizona Ecological Services Office (see FOR FURTHER 
INFORMATION CONTACT).

Background

    It is our intent to discuss only those topics directly relevant to 
the proposed reclassification and proposed designation of critical 
habitat for spikedace and loach minnow in this proposed rule. For more 
information on the species themselves, refer to the final listing rule 
(51 FR 23769, July 1, 1986 (spikedace), and 51 FR 39468, October 28, 
1986 (loach minnow)) and the previous critical habitat designation (72 
FR 13356, March 21, 2007).

Spikedace

    The spikedace is a member of the minnow family Cyprinidae, and is 
the only species in the genus Meda. The spikedace was first collected 
from the San Pedro River in 1851. The spikedace is a small, slim fish 
less than 75 millimeters (mm) (3 inches (in)) in length (Sublette et 
al. 1990, p. 136). Spikedace have olive-gray to brownish skin, with 
silvery sides and vertically elongated black specks. Spikedace have 
spines in the dorsal fin (Minckley 1973, pp. 82, 112, 115).
    Spikedace are found in moderate to large perennial streams, where 
they inhabit shallow riffles (those shallow portions of the stream with 
rougher, choppy water) with sand, gravel, and rubble substrates (Barber 
and Minckley 1966, p. 31; Propst et al. 1986, p. 12; Rinne and Kroeger 
1988, p. 1; Rinne 1991, pp. 8-10). Specific habitat for this species 
consists of shear zones where rapid flow borders slower flow; areas of 
sheet flow at the upper ends of mid-channel sand or gravel bars; and 
eddies at downstream riffle edges (Rinne 1991, p. 11; Rinne and Kroeger 
1988, pp. 1, 4). Recurrent flooding and a natural flow regime are very 
important in maintaining the habitat of spikedace and in helping 
maintain a competitive edge over invading nonnative aquatic species 
(Propst et al. 1986, pp. 76-81; Minckley and Meffe 1987, pp. 97, 103-
104).
    The spikedace was once common throughout much of the Gila River 
basin, including the mainstem Gila River upstream of Phoenix, and the 
Verde, Agua Fria, Salt, San Pedro, and San Francisco subbasins. Habitat 
destruction and competition and predation by nonnative aquatic species 
reduced its range and abundance (Miller 1961, pp. 365, 377, 397-398; 
Lachner et al. 1970, p. 22; Ono et al. 1983, p. 90; Moyle 1986, pp. 28-
34; Moyle et al. 1986, pp. 416-423; Propst et al. 1986, pp. 82-84).
    Spikedace are now restricted to portions of the upper Gila River 
(Grant, Catron, and Hidalgo Counties, New Mexico); Aravaipa Creek 
(Graham and Pinal Counties, Arizona); Eagle Creek (Graham and Greenlee 
Counties, Arizona); and the Verde River (Yavapai County, Arizona) 
(Marsh et al. 1990, pp. 107-108, 111; M. Brouder, U.S. Fish and 
Wildlife Service (Service), pers. comm. 2002; Stefferud and Reinthal 
2005, pp. 16-21; Paroz et al. 2006, pp. 62-67; Propst 2007, pp. 7-9, 
11-14).
    In 2007, spikedace were translocated into Hot Springs Canyon, in 
Cochise County, Arizona, and Redfield Canyon, in Cochise and Pima 
Counties, Arizona, and these streams were subsequently augmented 
(Robinson 2008a, pp. 2, 6; T. Robinson, Arizona Game and Fish 
Department (AGFD), pers. comm. 2008b; D. Orabutt, AGFD, pers. comm. 
2009; Robinson 2009a, pp. 2, 5-8). (We use the term ``translocate'' to 
describe stocking fish into an area where suitable habitat exists, but 
for which there are no documented collections.) Both Hot Springs and 
Redfield canyons are tributaries to the San Pedro River. Spikedace were 
also translocated into Fossil Creek, a tributary to the Verde River in 
Gila County, Arizona, in 2007, and were subsequently augmented in 2008 
(Carter 2007b, p. 1; Carter 2008a, p. 1; Robinson 2009b, p. 9; Boyarski 
et al. 2010, in draft, p. 7). In 2008, spikedace were translocated into 
Bonita Creek, a tributary to the Gila River in Graham County, Arizona 
(H. Blasius, U.S. Bureau of Land Management (BLM), pers. comm. 2008; D. 
Orabutt, AGFD, pers. comm. 2009; Robinson et al. 2009a, p. 209), and 
were repatriated to the upper San Francisco River in Catron County, New 
Mexico (D. Propst, New Mexico Department of Game and Fish (NMDGF), 
pers. comm. 2010). (We use the term ``repatriate'' to describe stocking 
fish into an area where we have historical records of prior presence.) 
Augmentations with additional fish will occur for the next several 
years at all sites, if adequate numbers of fish are available. 
Monitoring at each of these sites is ongoing to determine if 
populations ultimately become self-sustaining.
    The species is now common only in Aravaipa Creek in Arizona (AGFD 
1994; Arizona State University (ASU) 2002; P. Reinthal, University of 
Arizona, pers. comm. 2008, Reinthal 2009, pp. 1-2) and one section of 
the Gila River south of Cliff, New Mexico (NMDGF 2008; Propst et al. 
2009, pp. 14-17). The Verde River is presumed occupied; however, the 
last captured fish from this river was from a 1999 survey (M. Brouder, 
Service, pers. comm. 2002; AGFD 2004). Spikedace from the Eagle Creek 
population have not been seen for over a decade (Marsh 1996, p. 2), 
although they are still thought to exist in numbers too low for the 
sampling efforts to detect (Carter et al. 2007, p. 3; see Minckley and 
Marsh 2009). The Middle Fork Gila River population is thought to be 
very small and has not been seen since 1991 (Jakle 1992, p. 6), but 
sampling is localized and inadequate to detect a sparse population.
    Population estimates have not been developed as a result of the 
difficulty in detecting the species, the sporadic nature of most 
surveys, and the difference in surveying techniques that have been 
applied over time. Based on the available maps and survey information, 
we estimate the spikedace's present range to be approximately 10 
percent or less of its historical range, and the status of the species 
within occupied areas ranges from common to very rare. Data indicate 
that the population in New Mexico has declined in recent years (Paroz 
et al. 2006, p. 56). Historical and current records for spikedace are 
summarized in three databases (ASU 2002, AGFD 2004, NMDGF 2008), which 
are referenced throughout this document.
    A species' geographic range is the total area that encompasses all 
known locations of that species. As noted above, spikedace occur in 
several streams in portions of Arizona and New Mexico. For purposes of 
this document, we have used watershed boundaries associated with the 
Verde, Salt, San Pedro, Gila, and San Francisco rivers to define the 
geographic range of spikedace. All known records of spikedace occur 
within these watershed boundaries.
    We evaluated species detections and habitat descriptions in various 
databases, formal and informal survey records, agency and researcher 
field notes, and published literature to determine which geographic 
areas were reasonably occupied by the species at the time of listing. 
Surveys have been infrequent or inconsistent for this species. Further, 
even where surveys occur, the species can be difficult to detect due to 
its small body size. As a result, the lack of a positive detection in 
any specific area may not mean that the area is not occupied. 
Therefore, relying strictly on point-specific survey results

[[Page 66484]]

for historical occupancy information would likely create an incomplete 
picture of occupied area. The extent of a stream reach that is occupied 
up- or downstream of a known occupied site is generally limited only by 
availability of suitable habitat. Therefore, we assume that for areas 
where the species has been documented, it was likely also present in 
the adjacent stream segments if adjacent segments were connected and 
contain suitable habitat.
    In addition, this document discusses areas occupied at the time of 
listing. We are defining areas occupied at the time of listing to 
include streams for which we have spikedace records up to 1986, when 
they were first listed. These records include the Agua Fria River; the 
Verde River and its tributaries Beaver Creek and West Clear Creek; the 
Salt River and its tributary Tonto Creek; the San Pedro River and its 
tributary Aravaipa Creek; Eagle Creek; the San Francisco River; and the 
Gila River and its tributaries East, Middle, and West Fork Gila, and 
Blue Creek.

Loach Minnow

    The loach minnow is a member of the minnow family Cyprinidae. The 
loach minnow was first collected in 1851 from the San Pedro River in 
Arizona and was described by those specimens in 1865 by Girard (pp. 
191-192). The loach minnow is a small, slender fish less than 80 mm (3 
in) in length. It is olive-colored overall, with black mottling or 
splotches. Breeding males have vivid red to red-orange markings on the 
bases of fins and adjacent body, on the mouth and lower head, and often 
on the abdomen (Minckley 1973, p. 134; Sublette et al. 1990, p. 186).
    Loach minnow are found in small to large perennial streams and use 
shallow, turbulent riffles with primarily cobble substrate and swift 
currents (Minckley 1973, p. 134; Propst et al. 1988, pp. 36-43; Rinne 
1989, pp. 113-115; Propst and Bestgen 1991, pp. 29, 32-33). The loach 
minnow uses the spaces between, and in the lee (sheltered) side of, 
rocks for resting and spawning. It is rare or absent from habitats 
where fine sediments fill these interstitial spaces (Propst and Bestgen 
1991, p. 34).
    Loach minnow are now restricted to portions of the Gila River and 
its tributaries, the West, Middle, and East Fork Gila River (Grant, 
Catron, and Hidalgo Counties, New Mexico) (Paroz and Propst 2007, p. 
16; Propst 2007, pp. 7-8, 10-11, 13-14); the San Francisco and Tularosa 
rivers and their tributaries Negrito and Whitewater creeks (Catron 
County, New Mexico) (Propst et al. 1988, p. 15; ASU 2002; Paroz and 
Propst 2007, p. 16; Propst 2007, pp. 4-5); the Blue River and its 
tributaries Dry Blue, Campbell Blue, Pace, and Frieborn creeks 
(Greenlee County, Arizona and Catron County, New Mexico) (Miller 1998, 
pp. 4-5; ASU 2002; C. Carter 2005, pp. 1-5; C. Carter, AGFD, pers. 
comm. 2008b; Clarkson et al. 2008, pp. 3-4; Robinson 2009c, p. 3); 
Aravaipa Creek and its tributaries Turkey and Deer creeks (Graham and 
Pinal Counties, Arizona) (Stefferud and Reinthal 2005, pp. 16-21); 
Eagle Creek (Graham and Greenlee Counties, Arizona), (Knowles 1994, pp. 
1-2, 5; Bagley and Marsh 1997, pp. 1-2; Marsh et al. 2003, pp. 666-668; 
Carter et al. 2007, p. 3; Bahm and Robinson 2009a, p. 1); and the North 
Fork East Fork Black River (Apache and Greenlee Counties, Arizona) 
(Leon 1989, pp. 1-2; M. Lopez, AGFD pers. comm. 2000; S. Gurtin, AGFD, 
pers. comm. 2004; Carter 2007b, p. 2; Robinson et al. 2009b, p. 4); and 
possibly the White River and its tributaries, the East and North Fork 
White River (Apache, Gila, and Navajo Counties, Arizona). The present 
range is 15 to 20 percent of its historical range, and the status of 
the species within occupied areas ranges from common to very rare.
    As noted above, a species' range includes the total area that 
encompasses all known locations of that species. As with spikedace, 
loach minnow are known to occur in several streams in portions of 
Arizona and New Mexico. For purposes of this document, we have used 
watershed boundaries associated with the Verde, Salt, San Pedro, Gila, 
and San Francisco rivers to determine the range of loach minnow. All 
known loach minnow records occur within these watershed boundaries.
    We evaluated species detections and habitat descriptions in various 
databases, formal and informal survey records, agency and researcher 
field notes, and published literature to determine which geographic 
areas were reasonably occupied by the species at the time of listing. 
Surveys have been infrequent or inconsistent for this species. Further, 
even where surveys occur, the species can be difficult to detect due to 
its small body size. As a result, the lack of a positive detection in 
any specific area may not mean that the area is not occupied. 
Therefore, relying strictly on point-specific survey results for 
historical occupancy information would likely create an incomplete 
picture of occupied areas. The extent of a stream reach that is 
occupied up- or downstream of a known occupied site is generally 
limited only by availability of suitable habitat. Therefore, we assume 
that for areas where the species has been documented, it was likely 
also present in the adjacent stream segments if adjacent segments were 
connected and contain suitable habitat.
    In addition, this document discusses areas occupied at the time of 
listing. We are defining areas occupied at the time of listing to 
include streams for which we have loach minnow records up to 1986, when 
the species was first listed. These records include the Verde River and 
its tributary Beaver Creek; the White River and its tributary East Fork 
White River; Aravaipa Creek; the San Pedro River; Eagle Creek; the Blue 
River and its tributaries Campbell Blue, Dry Blue, and Little Blue 
creeks; the San Francisco River and its tributary Tularosa River; and 
the Gila River and its tributaries West Fork, Middle Fork, and East 
Fork Gila Rivers and Whitewater Creek. In addition, loach minnow were 
identified from several tributary streams following 1986. As no 
reintroduction efforts had taken place prior to discovering each of 
these populations, it is assumed they were occupied at listing, but 
undetected. We are therefore including these areas as occupied at 
listing: Deer Creek and Turkey Creek (tributaries to Aravaipa Creek); 
Frieborn Canyon and Pace Creek (tributaries to the Blue River); and 
North Fork East Fork Black River, and Negrito Creek (tributary to the 
Tularosa River).
    Although suitable habitat existed in Hot Springs, Redfield Canyons, 
Fossil Creek, or Bonita Creek, loach minnow had not previously been 
documented there. In 2007, loach minnow were translocated into Hot 
Springs and Redfield canyons in Cochise County, Arizona (Robinson 
2008a, pp. 2, 6; T. Robinson, AGFD, pers. comm. 2008b; D. Orabutt, 
AGFD, pers. comm. 2009); both of these streams are tributaries to the 
San Pedro River. Fish were also translocated into Fossil Creek, a 
tributary to the Verde River in Gila County, Arizona (Carter 2007a, p. 
1; Carter 2008a, p. 1; Robinson 2009b, p. 9; Orabutt and Robinson 2010, 
in draft, p. 12). In 2008, loach minnow were translocated into Bonita 
Creek, a tributary to the Gila River in Graham County, Arizona (H. 
Blasius, BLM, pers. comm. 2008; D. Orabutt, AGFD, pers. comm. 2009). 
Augmentations with additional fish will occur for the next several 
years. Monitoring will be conducted at each of these sites to determine 
if populations ultimately become established at these new locations.
    Loach minnow is now common only in Aravaipa Creek, the Blue River, 
and limited portions of the San Francisco, upper Gila, and Tularosa 
rivers in New Mexico. Since listing, loach minnow have been found in 
small tributary

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streams, including Pace, Frieborn, Negrito, Turkey, and Deer creeks 
(Stefferud and Reinthal 2005, pp. 16-21; Paroz and Propst 2007, p. 16; 
NMDGF 2008). In addition, two previously undocumented populations of 
loach minnow have been discovered, one in Eagle Creek (Knowles 1994, p. 
1; Marsh et al. 2003, p. 666) and one in the North Fork East Fork Black 
River (Bagley et al. 1997, p. 8). However, following a wildfire in the 
Black River watershed, a salvage rescue operation in the area known to 
be occupied by the loach minnow in 2004 resulted in the capture of only 
two loach minnow (S. Gurtin, AGFD, pers. comm. 2004). Both of these 
newly identified populations appear to be very small, but each 
represents a remnant portion of the historical range that was thought 
to be extirpated. Little information is available on the White River 
population due to the proprietary nature of Tribal survey information. 
Historical and current records for loach minnow are summarized in three 
databases (ASU 2002, AGFD 2004, NMDGF 2008), which are referenced 
throughout this document.

Previous Federal Actions

    The spikedace was listed as threatened on July 1, 1986 (51 FR 
23769); the loach minnow was listed as threatened on October 28, 1986 
(51 FR 39468). The Service received a petition to uplist these species 
from threatened to endangered status on September 22, 1993. On July 11, 
1994, we published 90-day and 12-month findings on the petition to 
amend the List of Threatened and Endangered Wildlife (59 FR 35303). We 
found that the petitioners presented substantial scientific information 
indicating that reclassifying spikedace and loach minnow as endangered 
was warranted but precluded by other listing actions (59 FR 35303). We 
restated this conclusion on January 8, 2001 (66 FR 1295), and 
considered the reclassification of spikedace and loach minnow each year 
in our Candidate Notice of Review. Our most recent Candidate Notice of 
Review was published on November 9, 2009 (74 FR 57804).
    We designated critical habitat for both species on March 8, 1994 
(59 FR 10898 (loach minnow); 59 FR 10906 (spikedace)). Those critical 
habitat designations were set aside by court order in Catron County 
Board of Commissioners, New Mexico v. U.S. Fish and Wildlife Service, 
CIV No. 93-730 HB (D.N.M. 1994) due to our failure to analyze the 
effects of critical habitat designation under the National 
Environmental Policy Act (NEPA) (42 U.S.C. 4321 et seq.).
    We subsequently published a proposed critical habitat designation 
on December 10, 1999 (64 FR 69324), and a final critical habitat 
designation on April 25, 2000 (65 FR 24328). However, in New Mexico 
Cattle Growers' Association and Coalition of Arizona/New Mexico 
Counties for Stable Economic Growth v. United States Fish and Wildlife 
Service, CIV 02-0199 JB/LCS (D.N.M), the plaintiffs challenged the 
April 25, 2000, critical habitat designation for the spikedace and 
loach minnow because the economic analysis had been prepared using the 
same methods that the Tenth Circuit had held to be invalid. The Service 
agreed to a voluntary vacatur of the critical habitat designation, 
except for the Tonto Creek Complex. On August 31, 2004, the United 
States District Court for the District of New Mexico set aside the 
April 25, 2000, critical habitat designation in its entirety and 
remanded it to the Service for preparation of a new proposed and final 
designation.
    On December 20, 2005, we published a proposed critical habitat 
designation (70 FR 75546), and on March 21, 2007, we published a final 
critical habitat designation (72 FR 13356) for the spikedace and loach 
minnow. In Coalition of Arizona/New Mexico Counties for Stable Economic 
Growth, et al . v. Salazar, et al. (D.N.M.), two sets of plaintiffs 
challenged the Service's critical habitat designation for the spikedace 
and the loach minnow on the grounds that we designated critical habitat 
without adequate delineation or justification. We filed a motion for 
voluntary remand of the final rule on February 2, 2009, in order to 
reconsider the final rule in light of a recently issued Department of 
the Interior Solicitor's Opinion, which discusses the Secretary of the 
Interior's authority to exclude areas from a critical habitat 
designation under section 4(b)(2) of the ESA. On May 4, 2009, the Court 
granted our motion for voluntary remand.
    There are differences in the areas included in this proposed 
designation from those included in the critical habitat designations 
published in 1994, 2000, and 2007. We have gained new information on 
species' distribution since the 1994 designation. We have acknowledged 
the flaws in the 2007 designation through our voluntary vacatur. This 
proposal is most similar to the 2000 designation. However, in contrast 
to the 2000 designation, we have not included every complex for 
spikedace and for loach minnow. Instead, we have attempted to consider 
occupancy data and habitat parameters specific to each species, and 
identified some areas that are suitable for one or the other species, 
but not both. While there is still considerable overlap in the 
designation, so that most areas are designated for both species, we 
have included some areas only for spikedace or only for loach minnow 
within this proposed designation.
    For more information on previous Federal actions concerning the 
spikedace and loach minnow, refer to previous publications, including 
listing documents published in 1985 and 1986 (50 FR 25380, June 18, 
1985; 50 FR 25390, June 18, 1985; 51 FR 39468, October 28, 1986; 51 FR 
23769, July 1, 1986), as well as previous critical habitat designations 
in 1994 (59 FR 10898, March 8, 1994; 59 FR 10906, March 8, 1994), 1999 
and 2000 (64 FR 69324, December 10, 1999; 65 FR 24328, April 25, 2000), 
and 2005 and 2007 (70 FR 75546, December 20, 2005; 72 FR 13356, March 
21, 2007).

Summary of Factors Affecting the Species

    Under the Act and our implementing regulations, a species may 
warrant listing if it is endangered or threatened throughout all or a 
significant portion of its range. Both spikedace and loach minnow 
currently exist in a small portion of their historical range (10 
percent, or less, for spikedace, and 15 to 20 percent for loach 
minnow), and the threats continue throughout its range. Accordingly, 
our assessment and determination applies to each species throughout its 
entire range.
    Section 4 of the Act (16 U.S.C. 1533), and implementing regulations 
(50 CFR part 424), set forth the procedures for adding species to the 
Federal Lists of Endangered and Threatened Wildlife and Plants. Under 
section 4(a)(1) of the Act, a species may be determined to be 
endangered or threatened based on any of the following five factors: 
(1) The present or threatened destruction, modification, or curtailment 
of its habitat or range; (2) overutilization for commercial, 
recreational, scientific, or educational purposes; (3) disease or 
predation; (4) the inadequacy of existing regulatory mechanisms; or (5) 
other natural or manmade factors affecting its continued existence. In 
making this finding, information pertaining to spikedace and loach 
minnow, in relation to the five factors provided in section 4(a)(1) of 
the Act, are discussed below.
    In considering what factors might constitute threats to a species, 
we must look beyond the exposure of the species to a factor to evaluate 
whether the species may respond to the factor in a way that causes 
actual impacts to the species. If there is exposure to a factor

[[Page 66486]]

and the species responds negatively, the factor may be a threat and we 
attempt to determine how significant a threat it is. The threat is 
significant if it drives, or contributes to, the risk of extinction of 
the species such that the species warrants listing as endangered or 
threatened as those terms are defined in the Act.

A. The Present or Threatened Destruction, Modification, or Curtailment 
of Habitat or Range

    The majority of historical native habitat for spikedace and loach 
minnow has been altered or destroyed. Activities such as groundwater 
pumping, surface water diversions, impoundments, dams, channelization 
(straightening of the natural watercourse, typically for flood control 
purposes), improperly managed livestock grazing, wildfire, agriculture, 
mining, road building, residential development, and recreation all 
contribute to habitat loss and stream habitat degradation in Arizona 
and New Mexico (Minckley and Deacon 1991, pp. 15-18; Tellman et al. 
1997, pp. 1, 4; Propst 1999, pp. 14-15; Minckley and Marsh 2009, pp. 
24-48).
    The aforementioned activities are human-caused; thus the local and 
regional effects of most of these activities are expected to increase 
with an increasing local human population. As of 2005, Arizona was 
recognized as the second fastest in Statewide population growth in the 
nation. The population of the State of Arizona is projected to grow by 
66 percent by the year 2030, while the population in New Mexico is 
expected to grow by 33 percent (Southwest Climate Change 2009, p. 1). 
Arizona experienced a 28.6 percent population growth from 2000 to 2009, 
while New Mexico experienced growth at 10.5 percent during the same 
period (U.S. Census Bureau 2010, pp. 1, 3). An example of this 
population growth is on the Verde River (Yavapai County, Arizona), 
which likely includes a remnant spikedace population, and is important 
recovery habitat for spikedace and loach minnow. Yavapai County 
experienced a 28.8 percent increase in human population between 2000 
and 2009. Groundwater use for municipal, industrial, and agricultural 
purposes has continued to increase since 1971 (Arizona Water Atlas 
2010, p. 292) which increases the competition for the limited water 
resources used by spikedace and loach minnow.
    Portions of some rivers receive protection as specially designated 
areas. In the upper Gila River, spikedace and loach minnow habitat 
receives some protection along the portions of the river that flow 
through the U.S. Forest Service Gila Wilderness and the Gila River 
Research Natural Area, which have use and access restrictions. Some 
portions of the river in the Gila National Forest are still affected by 
past and present uses within the watershed and riparian zone, such as 
grazing, timber harvest, and road development, and by water diversion 
for public and private uses. Other areas designated for special uses 
and subject to access and use restrictions include the Blue Range 
Primitive Area, the lower Gila River Bird Habitat Management Area, and 
the Gila River Research Natural Area.
Water Withdrawals
    Water resources are limited in the Southwestern United States and 
have led to the conversion of portions of habitat to intermittent 
streams or reservoirs unsuitable for spikedace or loach minnow. Growing 
water demands reduce southern Arizona perennial surface water in the 
Gila Basin, and threaten aquatic species. Historically, water 
withdrawals led to the conversion of large portions of flowing streams 
into intermittent streams, large reservoirs, or dewatered channels, 
thus eliminating suitable spikedace and loach minnow habitat in 
impacted areas (Propst et al. 1986, p. 3; Tellman et al. 1997, pp. 37, 
50, 63-64, 66, 103). These habitat changes, together with the 
introduction of nonnative fish species (see factors C and E), have 
resulted in the extirpation of spikedace and loach minnow throughout an 
estimated 80 to 90 percent of their historical ranges.
    After leaving the Mogollon Mountains in New Mexico, the Gila River 
is affected by agricultural and industrial water diversions, 
impoundment, and channelization. In the Gila River, agricultural 
diversions and groundwater pumping have caused declines in the water 
table, and surface flows in the central portion of the river basin are 
diverted for agriculture (Leopold 1997, pp. 63-64; Tellman et al. 1997, 
pp. 101-104; Arizona Department of Water Resources 2000, pp. 16-17). On 
the mainstem Salt River, impoundments have permanently limited the flow 
regime and suitability for spikedace or loach minnow.
    Of particular concern to spikedace and loach minnow survival in the 
Gila River is the implementation of Public Law 108-451, the Arizona 
Water Settlements Act. Title II of the Arizona Water Settlements Act 
would facilitate the exchange of Central Arizona Project water within 
and between southwestern river basins in Arizona and New Mexico. The 
Arizona Water Settlements Act may also result in the construction of 
new water development projects. For example, Section 212 of the Arizona 
Water Settlements Act pertains to the New Mexico Unit of the Central 
Arizona Project. Development of the New Mexico Unit may facilitate 
diversion of water via the construction of an on- or off-stream 
reservoir on the Gila River in New Mexico. Implementation of the 
Arizona Water Settlement Act is in its early stages on the Gila River, 
such that the exact location, scope, scale, timing, and effects of 
those efforts on the spikedace and its habitat in the Gila River cannot 
be definitively analyzed at present. However, should water be diverted 
from the river, there would be a diminished flow that could potentially 
result in direct and indirect loss and degradation of habitat for 
aquatic and riparian species. Because the Gila River is a stronghold 
for spikedace and loach minnow, impacts to those portions of the Gila 
River in New Mexico are of particular concern for the persistence of 
these species.
    The San Francisco River has undergone sedimentation, riparian 
habitat degradation, and extensive water diversion and at present has 
an undependable water supply throughout much of its length. Groundwater 
pumping also poses a threat to surface flows in the remaining spikedace 
and loach minnow habitat in Eagle Creek. Groundwater withdrawal in 
Eagle Creek, primarily for water supply for a large open-pit copper 
mine at Morenci, dries portions of the stream (Sublette et al. 1990, p. 
19; Service 2005; Propst et al. 1986, p. 7). Mining is the largest 
industrial water user in southeastern Arizona. The Morenci mine on 
Eagle Creek is North America's largest producer of copper, covering 
60,000 acres. Water for the mine is imported from the Black River, 
diverted from Eagle Creek as surface flows, or withdrawn from the Upper 
Eagle Creek Well Field (Arizona Department of Water Resources 2009, p. 
1).
    Aravaipa Creek is relatively protected from further habitat loss 
because it is within a Bureau of Land Management (BLM) Wilderness and 
is a Nature Conservancy preserve. However, Aravaipa Creek is affected 
by upstream uses in the watershed, primarily groundwater pumping for 
irrigation. Irrigation can reduce creek flows, as crop irrigation uses 
large amounts of water, especially during the summer months when the 
creek flows are already at their lowest. Increased groundwater pumping 
from wells is known to be linked to reduced creek flows (Fuller 2000, 
pp. 4-8).
    Water depletion is also a concern for the Verde River. In 2000, the 
Arizona Department of Water Resources (2000,

[[Page 66487]]

p. 1-1) reported that the populations of major cities and towns within 
the Verde River watershed had more than doubled in the last 20 years, 
resulting in more than a 39 percent increase in municipal water usage. 
The Arizona Department of Water Resources (2000, p. 1-1) anticipated 
that human populations in the Verde River watershed are expected to 
double again before 2040, resulting in more than a 400 percent increase 
over the 2000 water usage. The middle and lower Verde River has limited 
or no flow during portions of the year due to agricultural diversion 
and upstream impoundments, and has several impoundments in its middle 
reaches, which could expand the area of impacted spikedace and loach 
minnow habitat. The Little Chino basin within the Verde River watershed 
has already experienced significant groundwater declines that have 
reduced flow in Del Rio Springs (Arizona Department of Water Resources 
2000, pp. 1-1, 1-2). Blasch et al. (2006, p. 2) suggests that 
groundwater storage in the Verde River watershed has already declined 
due to groundwater pumping and reductions in natural channel recharge 
resulting from streamflow diversions.
    Also impacting water in the Verde River, the City of Prescott, 
Arizona, experienced a 22 percent increase in population between 2000 
and 2005 (U.S. Census Bureau 2010b, p. 1), averaging around 4 percent 
growth per year (City of Prescott 2010, p. 1). In addition, the towns 
of Prescott Valley and Chino Valley experienced growth rates of 66 and 
67 percent, respectively (Arizona Department of Commerce 2009a, p. 1; 
2009b, p. 1). This growth is facilitated by groundwater pumping in the 
Verde River basin. In 2004, the cities of Prescott and Prescott Valley 
purchased a ranch in the Big Chino basin in the headwaters of the Verde 
River, with the intent of drilling new wells to supply up to 
approximately 4,000 acre-feet (AF) of groundwater per year. If such 
drilling occurs, it could have serious adverse effects on the mainstem 
and tributaries of the Verde River. Scientific studies have shown a 
link between the Big Chino aquifer and spring flows that form the 
headwaters of the Verde River. It is estimated that 80 to 86 percent of 
baseflow in the upper Verde River comes from the Big Chino aquifer 
(Wirt 2005, p. G8). However, while these withdrawals could potentially 
dewater the upper 42 kilometers (km) (26 miles (mi)) of the Verde River 
(Wirt and Hjalmarson 2000, p. 4), it is uncertain that this project 
will occur given the legal and administrative challenges it faces. This 
upper portion of the Verde River is considered currently occupied by 
spikedace, and barrier construction and stream renovation plans are 
underway with the intention of using this historically occupied area 
for recovery of native fishes including loach minnow. Reductions of 
available water within this reach could preclude its use for recovery 
purposes. This area is currently considered occupied by spikedace, that 
are considered genetically (Tibbets 1993, pp. 25-29) and 
morphologically (Anderson and Hendrickson 1994, pp. 148, 150-154) 
distinct from all other spikedace populations.
    There are numerous surface water diversions in spikedace and loach 
minnow habitats, including the Verde River, Blue River, San Francisco 
River, Gila River, and Eagle Creek. Larger dams may prevent movement of 
fish between populations and dramatically alter the flow regime of 
streams through the impoundment of water (Ligon et al. 1995, pp. 184-
189). These diversions also require periodic maintenance and re-
construction, resulting in potential habitat damages and inputs of 
sediment into the active stream.
    Water withdrawals have occurred historically, and continue to 
occur, throughout the ranges of spikedace and loach minnow. Groundwater 
pumping and surface diversions used for agricultural, industrial, and 
municipal purposes can lead to declines in the water table and 
dewatering of active stream channels. Ongoing water withdrawals are 
known to occur on the Gila, San Francisco, and Verde rivers, and are 
occurring at limited levels, with the potential for increased 
withdrawal, on Aravaipa Creek.
Stream Channelization
    Sections of many Gila Basin rivers and streams have been, and 
continue to be, channelized for flood control, which disrupts natural 
channel dynamics (sediment scouring and deposition) and promotes the 
loss of riparian plant communities. Channelization changes the stream 
gradient above and below the channelization. Water velocity increases 
in the channelized section, which results in increased rates of erosion 
of the stream and its tributaries, accompanied by gradual deposits of 
sediment in downstream reaches that may increase the risk of flooding 
(Emerson 1971, p. 326; Simpson 1982, p. 122). Channelization can affect 
spikedace and loach minnow habitat by reducing its complexity, 
eliminating cover, reducing nutrient input, improving habitat for 
nonnative species, changing sediment transport, altering substrate 
size, increasing flow velocities, and reducing the length of the stream 
(and therefore the amount of aquatic habitat available) (Gorman and 
Karr 1978, pp. 512-513; Simpson 1982, p. 122; Schmetterling et al. 
2001, pp. 7-10). Historical and ongoing channelization will continue to 
contribute to riparian and aquatic habitat decline most notably 
eliminating cover and reducing nutrient input.
Water Quality
    In the past, the threat from water pollution was due primarily to 
catastrophic pollution events (Rathbun 1969, pp. 1-5; Eberhardt 1981, 
pp. 3-6, 8-10) or chronic leakage (Eberhardt 1981, pp. 2, 16) from 
large mining operations. Although this is not as large a problem today 
as it was historically, some damage to spikedace and loach minnow 
populations still occurs from occasional spills or chronic inability to 
meet water quality standards (United States v. ASARCO, No. 98-0137 PHX-
ROS (D. Ariz. June 2, 1998)). Mine tailings from a number of past and 
present facilities throughout the Gila Basin would threaten spikedace 
populations if catastrophic spills occur (Arizona Department of Health 
Services 2010, p. 3). Spills or discharges have occurred in the Gila 
River and affected streams within the watersheds of spikedace and loach 
minnow, including the Gila River, San Francisco River, San Pedro River, 
and some of their tributaries (Environmental Protection Agency 1997, 
pp. 24-67; Arizona Department of Environmental Quality 2000, p. 6; 
Church et al. 2005, p. 40; Arizona Department of Environmental Quality 
2007, p. 1).
    In January of 2006, the Arizona Department of Environmental Quality 
announced that it had been conducting a remedial investigation at the 
Klondyke Tailings site on Aravaipa Creek, which currently supports one 
of the two remaining populations where spikedace and loach minnow are 
considered common. The Klondyke tailings site was a mill that processed 
ore to recover lead, zinc, copper, silver, and gold between the 1920s 
and the 1970s. There are eight contaminants in the tailings and soil at 
the Klondyke tailings site that are at levels above regulatory limits. 
These contaminants include antimony, arsenic, beryllium, cadmium, 
copper, lead, manganese, and zinc. Samples of shallow groundwater 
collected at the site contained arsenic, beryllium, cadmium, chromium, 
lead, and nickel above regulatory limits (Arizona Department of 
Environmental Quality 2006, p. 2). A preliminary study in Aravaipa 
Creek has found high levels of

[[Page 66488]]

lead in two other native fish species, Sonora sucker (Catostomus 
insignis) and roundtail chub (Gila robusta), as well as in the sediment 
and in some of the invertebrates. These lead levels are high enough 
that they could negatively impact reproduction (P. Reinthal, University 
of Arizona pers. comm. 2010). We do not know with certainty whether 
these levels of lead would affect spikedace or loach minnow, but we 
assume the same negative effects would occur.
    Pollution is increasingly more widespread and more often from non-
point sources. Urban and suburban development is one source of non-
point pollution. Increasing the area subject to runoff from roads, golf 
courses, and other sources of petroleum products, pesticides, and other 
toxic materials, can cause changes in fish communities (Wang et al. 
1997, pp. 6, 9, 11). Nutrient and sediment loads are increasing in 
urban areas (King et al. 1997, pp. 7-24, 38, 39) and, combined with 
depleted stream flows, can be serious threats to aquatic ecosystem 
during some periods of the year. Bridges and roads increase with 
increasing rural and urban populations in Arizona (Arizona Department 
of Transportation 2000, pp. 1-3), and pose significant risks to the 
fish from increases in toxic materials along roadways (Trombulak and 
Frissall 2000, pp. 22-24). As noted previously, human populations 
within the ranges of spikedace and loach minnow are expected to 
increase over the next 20 years. Therefore, we expect a corresponding 
increase in non-point source pollution.
    Based on historical records and long-term tree-ring records, 
wildfires have increased in the ponderosa pine forests of the 
Southwest, including the range of the spikedace and loach minnow 
(Swetnam and Betancourt 1990, pp. 1017, 1019; Swetnam and Betancourt 
1998, pp. 3131-3135). This is due to a combination of decades of fire 
suppression, increases in biomass due to increased precipitation after 
1976, and warming temperatures coupled with recent drought conditions 
(University of Arizona 2006, pp. 1, 3). As wildfires increase, so does 
the use of fire retardant chemical applications. Some fire retardant 
chemicals are ammonia-based, which is toxic to aquatic wildlife; 
however, many formulations also contain yellow prussiate of soda 
(sodium ferrocyanide), which is added as an anticorrosive agent. Such 
formulations are toxic for fish, aquatic invertebrates, and algae 
(Angeler et al. 2006, pp. 171-172; Calfee and Little 2003, pp. 1527-
1530; Little and Calfee 2002, p. 5; Buhl and Hamilton 1998, p. 1598; 
Hamilton et al. 1998, p. 3; Gaikwokski et al. 1996, pp. 1372-1373). 
Toxicity of these formulations is enhanced by sunlight (Calfee and 
Little 2003, pp. 1529-1533). In a 2008 biological opinion issued by the 
U.S. Fish and Wildlife Service to the Forest Service on the nationwide 
use of fire retardants, the U.S. Fish and Wildlife Service concluded 
that the use of fire retardants can cause mortality to fish by exposing 
them to ammonia. We concluded in the opinion that the proposed action, 
which included the application of fire retardants throughout the range 
of the species, was likely to jeopardize the continued existence of the 
spikedace and loach minnow (Service 2008a).
    Severe wildfires capable of extirpating or decimating fish 
populations are a relatively recent phenomenon, and result from the 
cumulative effects of historical or ongoing grazing (removes the fine 
fuels needed to carry fire) and fire suppression (Madany and West 1983, 
pp. 665-667; Savage and Swetnam 1990, p. 2374; Swetnam 1990, p. 12; 
Touchan et al. 1995, pp. 268-271; Swetnam and Baisan 1996, p. 29; 
Belsky and Blumenthal 1997, pp. 315-316, 324-325; Gresswell 1999, pp. 
193-194, 213). Historical wildfires were primarily cool-burning 
understory fires with return intervals of 4 to 8 years in ponderosa 
pine (Swetnam and Dieterich 1985, pp. 390, 395). Cooper (1960, p. 137) 
concluded that prior to the 1950s, crown fires were extremely rare or 
nonexistent in the region. However, since 1989, high-severity wild 
fires, and subsequent floods and ash flows, have caused the extirpation 
of several populations of Gila trout in the Gila National Forest, New 
Mexico (Propst et al. 1992, pp. 119-120, 123; Brown et al. 2001, pp. 
140-141). It is not known if spikedace or loach minnow have suffered 
local extirpations; however, native fishes, including spikedace and 
loach minnow, in the West Fork Gila River, showed 60 to 80 percent 
decreases in population following the Cub Fire in 2002, due to flooding 
events after the fire (Rinne and Carter 2008, pp. 171). Increased fines 
and ash may be continuing to affect the populations on the West Fork 
Gila, near the Gila Cliff Dwellings (D. Propst. NMDGF, pers. comm. 
2004).
    Effects of fire may be direct and immediate or indirect and 
sustained over time. Because spikedace and loach minnow are found 
primarily in the lower elevation, higher-order streams, they are most 
likely affected by the indirect effects of fire (e.g., ash flows), not 
direct effects (e.g., drastic changes in pH, ammonium concentrations). 
Indirect effects of fire include ash and debris flows, increases in 
water temperature, increased nutrient inputs, and sedimentation (Propst 
et al. 1992, pp. 119-120; Gresswell 1999, pp. 194-211; Rinne and Carter 
2008, pp. 169-171). Of these, ash flows probably have the greatest 
effect on spikedace and loach minnow. Ash and debris flows may occur 
months after fires, when barren soils are eroded during monsoonal rain 
storms (Bozek and Young 1994, pp. 92-94). Ash and fine particulate 
matter created by fire can fill the interstitial spaces between gravel 
particles, eliminating spawning habitat or, depending on the timing, 
suffocating eggs that are in the gravel. Ash and debris flows can also 
decimate aquatic invertebrate populations that the fish depend on for 
food (Molles 1985, p. 281).
Recreation
    The impacts to spikedace and loach minnow from recreation can 
include movement of livestock along streambanks, trampling, loss of 
vegetation, and increased danger of fire (Northern Arizona University 
2005, p. 136; Monz et al. 2010, pp. 553-554). In the arid Gila River 
Basin, recreational impacts are disproportionately distributed along 
streams as a primary focus for recreation (Briggs 1996, p. 36). Within 
the range of spikedace and loach minnow, the majority of the occupied 
areas occur on Federal lands, which are managed for recreation and 
other purposes. Spikedace and loach minnow are experiencing increasing 
habitat impacts from such use in some areas. For example, Fossil Creek 
experienced an increase in trail use at one site, with an estimated 
8,606 hikers using the trail in 1998, and an estimated 19,650 hikers 
using the trail in 2003. Dispersed camping also occurs in the area. The 
greatest impacts from camping were vegetation loss and litter (Northern 
Arizona University 2005, pp. 134-136). Similar impacts have been 
observed at Aravaipa Creek. Vegetation loss is often accompanied by 
soil compaction, which when combined with vegetation loss, can result 
in increased runoff and sedimentation in waterways (Monz et al. 2010, 
pp. 551-553; Andereck 1993, p. 2).
Roads and Bridges
    Roads impact Gila River Basin streams (Dobyns 1981, pp. 120-129, 
167, 198-201), including spikedace, loach minnow, and their habitats 
(Jones et al. 2000, pp. 82-83). The need for bridges and roads 
increases with increasing rural and urban populations in Arizona 
(Arizona Department of

[[Page 66489]]

Transportation 2000, pp. 1-3). In addition, existing roads and bridges 
have ongoing maintenance requirements that result in alterations of 
stream channels within spikedace and loach minnow habitats (Service 
1994a, pp. 8-12; Service 1995a, pp. 10-12; Service 1995b, pp. 5-7; 
Service 1997a, pp. 10-15; Service 1997b, pp. 54-77). Bridge 
construction or repair causes channel alteration and, if not carefully 
executed, can result in long-term channel adjustments, altering 
habitats upstream and downstream. In some areas, low-water ford 
crossings exist within occupied spikedace and loach minnow habitats and 
cause channel modification and habitat disruption. Low-water crossings 
on general-use roads exist in a number of areas that may support 
spikedace and loach minnow. These crossings frequently require 
maintenance following minor flooding.
    Repeated road repairs near the Gila Cliff Dwellings on the West 
Fork Gila River have occurred because the bridge span is too short to 
accommodate peak flows. This is a common problem on bridges that cross 
the Gila River, and on other rivers occupied by spikedace and loach 
minnow in the Southwest. In an attempt to protect bridges, large 
amounts of fill (such as boulders, rip rap, and dirt) are used to 
confine and redirect the river. Typically, this habitat alteration is 
detrimental to spikedace and loach minnow because it changes the 
channel gradient and substrate composition, and reduces habitat 
availability. Eventually, peak flows remove the fill material, roads 
and bridges are damaged, and the resulting repairs and reconstruction 
lead to additional habitat disturbance (Service 1998, 2002, 2005, 
2008b, 2008c, 2009, 2010a).
Livestock Grazing
    Livestock grazing has been one of the most widespread and long-term 
adverse impacts to native fishes and their habitat (Miller 1961, pp. 
394-395, 399), but is one of the few threats where adverse effects to 
species such as spikedace and loach minnow are decreasing, due to 
improved management on Federal lands (Service 1997c, pp. 121-129, 137-
141; Service 2001, pp. 50-67). This improvement occurred primarily by 
discontinuing grazing in the riparian and stream corridors. However, 
although adverse effects are less than in the past, livestock grazing 
within watersheds where spikedace and loach minnow and their habitats 
are located continues to cause adverse effects. These adverse effects 
occur through watershed alteration and subsequent changes in the 
natural flow regime, sediment production, and stream channel morphology 
(Platts 1990, pp. I-9--I-11; Belsky et al. 1999, pp. 1-3, 8-10; Service 
2001, pp. 50-67).
    Livestock grazing can destabilize stream channels and disturb 
riparian ecosystem functions (Platts 1990, pp. I-9--I-11; Armour et al. 
1991, pp. 7-10; Tellman et al. 1997, pp. 20-21, 33, 47, 101-102). 
Improper livestock grazing can negatively affect spikedace and loach 
minnow through removal of riparian vegetation (Propst et al. 1986, p. 
3; Clary and Webster 1989, p. 1; Clary and Medin 1990, p. 1; Schulz and 
Leininger 1990, p. 295; Fleishner 1994, pp. 631-633, 635-636), which 
can result in reduced bank stability and higher water temperatures 
(Kauffman and Krueger 1984, pp. 432-434; Platts and Nelson 1989, pp. 
453, 455; Fleishner 1994, pp. 635-636; Belsky et al. 1999, pp. 2-5, 9-
10). Livestock grazing can also cause increased sediment in the stream 
channel, due to streambank trampling and riparian vegetation loss 
(Weltz and Wood 1986, pp. 364-368; Pearce et al. 1998, pp. 302, 307; 
Belsky et al. 1999, p. 10). Livestock can physically alter the 
streambank through trampling and shearing, leading to bank erosion 
(Trimble and Mendel 1995, pp. 243-244; Belsky et al. 1999, p. 1). In 
combination, loss of riparian vegetation and bank erosion can alter 
channel morphology, including increased erosion and deposition, 
increased sediment loads, downcutting, and an increased width-to-depth 
ratio, all of which lead to a loss of spikedace and loach minnow 
habitat components. Livestock grazing management also continues to 
include construction and maintenance of open stock tanks, which are 
often stocked with nonnative aquatic species harmful to spikedace and 
loach minnow (Service 1997b, pp. 54-77) if they escape or are 
transported to waters where these native fish occur.
Summary of Factor A
    Impacts associated with roads and bridges, changes in water 
quality, and recreation have altered or destroyed many of the rivers, 
streams, and watershed functions in the ranges of the spikedace and 
loach minnow. As discussed above, activities such as groundwater 
pumping, surface water diversions, impoundments, dams, channelization, 
improperly managed livestock grazing, wildfire, agriculture, mining, 
road building, residential development, and recreation all contribute 
to riparian habitat loss and degradation of aquatic resources in 
Arizona and New Mexico. Changes in flow regimes are expected to 
continue into the foreseeable future. Therefore, we find that the 
spikedace and loach minnow are threatened by the destruction, 
modification, or curtailment of their habitats.

B. Overutilization for Commercial, Recreational, Scientific, or 
Educational Purposes

    Currently, collection of spikedace and loach minnow in Arizona is 
prohibited by Arizona Game and Fish Commission Order 40, except where 
such collection is authorized by special permit (AGFD 2009, p. 5). The 
collection of these species is prohibited in the State of New Mexico 
except by special scientific permit (NMDGF 2010, p. 4). Because 
spikedace and loach minnow do not grow larger than 80 mm (3 in), we 
believe that angling for this species is not a threat. No known 
commercial uses exist for spikedace or loach minnow. A limited amount 
of scientific collection occurs, but does not pose a threat to these 
species because it is regulated by the States. Therefore, we have 
determined that overutilization for commercial, recreational, 
scientific, or educational purposes is not a threat to spikedace or 
loach minnow.

C. Disease or Predation

    The introduction and spread of nonnative species has been 
identified as one of the primary factors in the continuing decline of 
native fishes throughout North America and particularly in the 
Southwest (Miller 1961, pp. 365, 397-398; Lachner et al. 1970, p. 21; 
Ono et al. 1983, pp. 90-91; Carlson and Muth 1989, pp. 222, 234; Fuller 
et al. 1999, p. 1). Miller et al. (1989, pp. 22, 34, 36) concluded that 
introduced nonnative species were a causal factor in 68 percent of fish 
extinctions in North America in the last 100 years. For the 70 percent 
of fish species that are still extant, but are considered to be 
endangered or threatened, introduced nonnative species are a primary 
cause of the decline (Lassuy 1995, pp. 391-394). Release or dispersal 
of new nonnative aquatic organisms is a continuing phenomenon in the 
species' range (Rosen et al. 1995, p. 254). Currently, all native 
fishes in Arizona and 80 percent of native fishes in the Southwest are 
on either State or Federal protection lists.
    Nonnative fish introductions in the Southwestern United States 
began before 1900, and have steadily increased in frequency (Rinne and 
Stefferud 1996b, p. 29). New species are continually being introduced 
through various mechanisms, including aquaculture, aquarium trade, 
sport fish stocking, live bait use, interbasin water

[[Page 66490]]

transfers, and general ``bait bucket transport,'' where people move 
fish from one area to another without authorization and for a variety 
of purposes (Service 1994b, pp. 12-16; Service 1999, pp. 24-59). Nearly 
100 kinds of nonnative fishes have been stocked or introduced into 
streams in the Southwest (Minckley and Marsh 2009, p. 51). Nonnative 
fishes known to occur within the historical range of the spikedace 
include channel catfish (Ictalurus punctatus), flathead catfish 
(Pylodictis olivaris), red shiner (Cyprinella lutrensis), fathead 
minnow (Pimephales promelas), green sunfish (Lepomis cyanellus), 
largemouth bass (Micropterus salmoides), smallmouth bass (Micropterus 
dolomieui), rainbow trout (Oncorhynchus mykiss), mosquitofish (Gambusia 
affinis), carp (Cyprinus carpio), bluegill (Lepomis macrochiris), 
yellow bullhead (Ameiurus natalis), black bullhead (Ameiurus melas), 
and goldfish (Carassius auratus) (ASU 2002).
    In the Gila River basin, introduction of nonnative species is 
considered a primary factor in the decline of native fish species 
(Minckley 1985, pp. 1, 68; Williams et al. 1985, pp. 1-2; Minckley and 
Deacon 1991, pp. 15-17; Douglas et al. 1994, pp. 9-11; Clarkson et al. 
2005 p. 20; Olden and Poff 2005, pp. 79-87). Aquatic and semi-aquatic 
mammals, reptiles, amphibians, crustaceans, mollusks (snails and 
clams), parasites, disease organisms, and aquatic and riparian vascular 
plants outside of their historical range, have all been documented to 
adversely affect aquatic ecosystems (Cohen and Carlton 1995, pp. i-iv). 
The effects of nonnative fish competition on spikedace and loach minnow 
can be classified as either interference or exploitive. Interference 
competition occurs when individuals directly affect others, such as by 
fighting, producing toxins, or preying upon them (Schoener 1983, p. 
257). Exploitive competition occurs when individuals affect others 
indirectly, such as through use of common resources (Douglas et al. 
1994, p. 14). Interference competition in the form of predation is 
discussed here, while a discussion of the history of nonnative species 
introductions and resulting interference competition for resources are 
discussed under Factor E below.
Predation
    Nonnative channel catfish, flathead catfish, and smallmouth bass 
all prey on spikedace and loach minnow, as indicated by prey remains of 
native fishes in the stomachs of these species (Propst et al. 1986, p. 
82; Propst et al. 1988, p. 64; Bonar et al. 2004, pp. 13, 16-21). 
Channel catfish move into riffles to feed, preying on the same animals 
most important to loach minnows, while juvenile flathead catfish prey 
on loach minnows (Service 1991a, p. 5). Smallmouth bass are known to 
co-occur with spikedace and are documented predators of the species 
(Service 1991b, p. 6). Green sunfish are also thought to be a predator, 
likely responsible for replacement of native species like spikedace and 
loach minnow. While no direct studies have been completed on predation 
by green sunfish on spikedace or loach minnow, they are a known 
predator of fish that size, and they occur within areas occupied by 
these species.
    Declines of native fish species appear linked to increases in 
nonnative fish species. For example, in 1949, 52 spikedace were 
collected at Red Rock on the Gila River, while channel catfish composed 
only 1.65 percent of the 607 fish collected. However, in 1977, only six 
spikedace were located at the same site, and the percentage of channel 
catfish had risen to 14.5 percent of 169 fish collected. The decline of 
spikedace and the increase of channel catfish is likely related 
(Anderson 1978, pp. 2, 13, 50-51). Similarly, interactions between 
native and nonnative fishes were observed in the upper reaches of the 
East Fork of the Gila River. Prior to the 1983 and 1984 floods in the 
Gila River system, native fish were limited, with spikedace being rare 
or absent, while nonnative channel catfish and smallmouth bass were 
moderately common. After the 1983 flooding, adult nonnative predators 
were generally absent, and spikedace were collected in moderate numbers 
in 1985 (Propst et al. 1986, p. 83).
    The majority of areas considered occupied by spikedace and loach 
minnow have seen a shift from a predominance of native fishes to a 
predominance of nonnative fishes. For spikedace, this is best 
demonstrated on the upper Verde River, where native species dominated 
the total fish community at greater than 80 percent from 1994 to 1996, 
before dropping to approximately 20 percent in 1997 and 19 percent in 
2001. At the same time, three nonnative species increased in abundance 
between 1994 and 2000 (Rinne et al. 2004, pp. 1-2). Similar changes in 
the dominance of nonnative fishes have occurred on the Middle Fork Gila 
River, with a 65 percent decline of native fishes between 1988 and 2001 
(Propst 2002, pp. 21-25).
    In other areas, nonnative fishes may not dominate the system, but 
their abundance has increased, while spikedace and loach minnow 
abundance has declined. This is the case for the Cliff-Gila Valley area 
of the Gila River, where nonnative fishes increased from 1.1 percent to 
8.5 percent, while native fishes declined steadily over a 40-year 
period (Propst et al. 1986, pp. 27-32). At the Redrock and Virden 
valleys on the Gila River, the relative abundance in nonnative fishes 
in the same time period increased from 2.4 percent to 17.9 percent 
(Propst et al. 1986, pp. 32-34). Four years later, the relative of 
abundance of nonnative fishes increased to 54.7 percent at these sites 
(Propst et al. 1986, pp. 32-36). The percentage of nonnative fishes 
increased by almost 12 percent on the Tularosa River between 1988 and 
2003, while on the East Fork Gila River, nonnative fishes increased to 
80.5 percent relative abundance in 2003 (Propst 2005, pp. 6-7, 23-24). 
Nonnative fishes are also considered a management issue in other areas 
including Eagle Creek, the San Pedro River, West Fork Gila River, and 
to a lesser extent on the Blue River and Aravaipa Creek.
    Generally, when the species composition of a community shifts in 
favor of nonnative fishes, a decline in spikedace or loach minnow 
abundance occurs (Olden and Poff 2005, pp. 79-86). Propst et al. (1986, 
p. 38) noted this during studies of the Gila River between 1960 and 
1980. While native species, including spikedace, dominated the study 
area initially, red shiner, fathead minnow, and channel catfish were 
more prevalent following 1980. Propst et al. (1986, pp. 83-86) noted 
that drought and diversions for irrigation first brought a decline in 
habitat quality, followed by the establishment of nonnative fishes in 
remaining suitable areas, thus reducing the availability and utility of 
these areas for native species. It should be noted that the effects of 
nonnative fishes often occur with, or are exacerbated by, changes in 
flow regimes or declines in habitat conditions (see Factor A above) and 
should be considered against the backdrop of historical habitat 
degradation that has occurred over time (Minckley and Meffe 1987, pp. 
94, 103; Rinne 1991, p. 12).
    Nonnative channel catfish, flathead catfish, and smallmouth bass 
are present in most spikedace habitats, including the Verde River 
(Minckley 1993, pp. 7-13; Jahrke and Clark 1999, pp. 2-7; Rinne 2004, 
pp. 1-2; Bahm and Robinson 2009, pp. 1-4; Robinson and Crowder 2009, 
pp. 3-5); the Gila River (Propst et al. 1986, pp. 14-31; Springer 1995, 
pp. 6-10; Jakle 1995, pp. 5-7; Propst et al. 2009, pp. 14-17); the San 
Pedro River (Jakle 1992, pp. 3-5; Minckley 1987, pp. 2, 16); the San 
Francisco River (Papoulias et al. 1989, pp. 77-80; Propst et al. 2009, 
pp. 5-6);

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the Blue River (ASU 1994, multiple reports; ASU 1995, multiple reports; 
Clarkson et al. 2008, pp. 3-4); the Tularosa River, East Fork Gila 
River, West Fork Gila River, and Middle Fork Gila River (Propst et al. 
2009, pp. 7-13; NMDGF 2009 in draft, pp. 2-14); and Eagle Creek (Marsh 
et al. 2003, p. 667; ASU 2008, multiple reports; Bahm and Robinson 
2009a, pp. 2-6).
    Pilger et al. (2010, pp. 311-312) studied the food webs in six 
reaches of the Gila River. Their study attempted to quantify resource 
overlap among native and nonnative fishes. Their study determined that 
nonnative fishes consumed a greater diversity of invertebrates and more 
fish than native species, and that nonnative fishes consumed predacious 
invertebrates and terrestrial invertebrates more frequently than native 
fishes. They found that, on average, the diets of adult nonnative 
fishes were comprised of 25 percent fish, but that there was high 
variability among species. Only 6 percent of the diet of channel 
catfish was fish, while fish made up 84 percent of the diet of flathead 
catfish. They found that both juvenile and adult nonnative species 
could pose a predation threat to native fishes.
    As noted below under Factor E, nonnative fishes also compete for 
resources with native fishes. While nonnative fishes were preying on 
native fishes, small-bodied nonnative fishes are potentially affecting 
native fishes through competition (discussed further under Factor E), 
so that native fishes are impacted by both competition and predation. 
Pilger et al. (2010, p. 312) note that removal and preclusion of 
nonnative predators and competitors may be necessary for conservation 
of native fishes in the upper Gila River in order to mitigate the 
effects they have on native species. Pilger et al. (2010, p. 312) note 
that, in the upper Verde River, native fishes have declined 
precipitously since the mid-1990s, which may indicate that a stressor 
threshold has been crossed. They conclude that there are declining 
trends of native fish abundances in the upper Gila River, and that the 
coexistence of native and nonnative fishes there may indicate that the 
threshold has not been reached, but may be imminent.
Disease
    Various parasites may affect spikedace and loach minnow. Asian 
tapeworm (Bothriocephalus acheilognathi) was introduced into the United 
States with imported grass carp (Ctenopharyngodon idella) in the early 
1970s. It has since become well established in areas throughout the 
southwestern United States. The definitive host in the life cycle of 
Asian tapeworm is a cyprinid fish (carp or minnow), and therefore it is 
a potential threat to spikedace and loach minnow, as well as other 
native cyprinids in Arizona. The Asian tapeworm adversely affects fish 
health by impeding the digestion of food as it passes through the 
intestinal track. Emaciation and starvation of the host can occur when 
large enough numbers of worms feed off of the fish directly. An 
indirect effect is that weakened fish are more susceptible to infection 
by other pathogens. Asian tapeworm invaded the Gila River basin and was 
found during the Central Arizona Project's fall 1998 monitoring in the 
Gila River at Ashurst-Hayden Dam. It has also been confirmed from 
Bonita Creek in 2010 and from Fossil Creek in 2004 and 2010 (U.S. Fish 
and Wildlife Service National Wild Fish Health Survey 2004, 2010). This 
parasite can infect many species of fish and is carried into new areas 
along with nonnative fishes or native fishes from contaminated areas.
    The parasite (Ichthyophthirius multifiliis) (Ich) usually occurs in 
deep waters with low flow and is a potential threat to spikedace and 
loach minnow. Ich has occurred in some Arizona streams, probably 
encouraged by high temperatures and crowding as a result of drought 
(Mpoame 1982, pp. 45-47). This parasite was observed being transmitted 
on the Sonora sucker (Catostomus insignis), although it does not appear 
to be host-specific and could be transmitted by other species (Mpoame 
1982, p. 46). It has been found on desert and Sonoran suckers, as well 
as roundtail chub (Robinson et al. 1998, p. 603). This parasite becomes 
embedded under the skin and within the gill tissues of infected fish. 
When Ich matures, it leaves the fish, causing fluid loss, physiological 
stress, and sites that are susceptible to infection by other pathogens. 
If Ich is present in large enough numbers, it can also impact 
respiration because of damaged gill tissue. There are recorded 
spikedace mortalities in captivity due to Ich. Ich is known to be 
present in Aravaipa Creek (Mpoame 1982, p. 46), which is currently 
occupied by both spikedace and loach minnow.
    Anchor worm (Lernaea cyprinacea), an external parasite, is unusual 
in that it has little host specificity, infecting a wide range of 
fishes and amphibians. Infection by this parasite has been known to 
kill large numbers of fish due to tissue damage and secondary infection 
of the attachment site (Hoffnagle and Cole 1999, p. 24). Presence of 
this parasite in the Gila River basin is a threat to spikedace, loach 
minnow, and other native fishes. In July 1992, the BLM found anchor 
worms in Bonita Creek. They have also been documented in Aravaipa Creek 
and the Verde River (Robinson et al. 1998, pp. 599, 603-605). Both 
spikedace and loach minnow occur in Bonita and Aravaipa Creeks.
Summary of Factor C
    Both spikedace and loach minnow have been severely impacted by the 
presence of nonnative predators. Aquatic nonnative species have been 
introduced or spread into new areas through a variety of mechanisms, 
including intentional and accidental releases, sport stocking, 
aquaculture, aquarium releases, and bait-bucket release. Channel 
catfish, flathead catfish, and smallmouth bass appear to be the most 
prominent predators, although other species contribute to the decline 
of native fishes in the Southwest, including spikedace and loach 
minnow. Spikedace and loach minnow have been replaced by nonnative 
fishes in several Arizona streams. In addition to threats from 
predation, we also conclude that both spikedace and loach minnow are 
reasonably certain to become impacted by parasites that have been 
documented in the Gila River basin and that are known to adversely 
affect or kill fish hosts. For these reasons, we find that the 
spikedace and loach minnow are threatened by disease and predation.

D. The Inadequacy of Existing Regulatory Mechanisms

    Because of the complex, indirect, and cumulative nature of many of 
the threats to spikedace and loach minnow, existing regulatory 
mechanisms are often inadequate to address or ameliorate the threats. 
Causes of the declining status of these species are a mix of many human 
activities and natural events, which makes it difficult to remove those 
threats through regulation. Spikedace is listed by New Mexico as an 
endangered species, while loach minnow is listed as threatened (Bison-M 
2010). These designations provide the protection of the New Mexico 
Wildlife Conservation Act. However, the primary focus of the New Mexico 
Wildlife Conservation Act and other State legislation is to prevent 
actual destruction or harm to individuals of the species. Since most of 
the threats to these species come from actions that do not directly 
kill individuals, but indirectly result in their death from the lack of 
some habitat requirement or an inability to reproduce, the State 
protection is only

[[Page 66492]]

partially effective for this species. Similarly, spikedace and loach 
minnow are listed as species of concern by the State of Arizona. The 
listing under the State of Arizona law does not provide protection to 
the species or their habitats; however, AGFD regulations prohibit 
possession of these species (AGFD 2006, Appendix 10, p. 4).
    As discussed above under Factor C, the introduction and spread of 
nonnative aquatic species is a major threat to spikedace and loach 
minnow. Neither the States of New Mexico and Arizona nor the Federal 
government has adequate regulatory mechanisms to address this issue. 
Programs to introduce, augment, spread, or permit such actions for 
nonnative sport, bait, aquarium, and aquaculture species continue. 
Regulation of these activities does not adequately address the spread 
of nonnative species, as many introductions are conducted through 
incidental or unregulated actions.
    New Mexico water law does not include provisions for instream water 
rights to protect fish and wildlife and their habitat. Arizona water 
law does recognize such provisions; however, because this change is 
relatively recent, instream water rights have low priority and are 
often overcome by more senior diversion rights. Arizona State law also 
allows surface water depletion by groundwater pumping.
    There are many Federal statutes that potentially afford protection 
to spikedace and loach minnow. A few of these are section 404 of the 
Clean Water Act (33 U.S.C. 1251 et seq.), Federal Land Policy and 
Management Act (43 U.S.C. 1701-1782), National Forest Management Act 
(16 U.S.C. 1600 et seq.), NEPA, and the Act. However, in practice these 
statutes have not been able to provide sufficient protection to prevent 
the downward trend in the populations and habitat of spikedace and 
loach minnow and the upward trend in threats. Section 404 of the Clean 
Water Act regulates placement of fill into waters of the United States, 
including most of spikedace and loach minnow habitat. However, many 
actions highly detrimental to spikedace and loach minnow and their 
habitats, such as gravel mining and irrigation diversion structure 
construction and maintenance, are often exempted from the Clean Water 
Act. Other detrimental actions, such as bank stabilization and road 
crossings, are covered under nationwide permits that receive little or 
no Service review. A lack of thorough, site-specific analyses for 
projects can allow substantial adverse effects to spikedace, loach 
minnow, and their habitat.
    The Federal Land Policy and Management Act and National Forest 
Management Act provide mechanisms for protection and enhancement of 
spikedace, loach minnow, and their habitat on Federal lands; however, 
these laws have been in effect longer than the 24 years since spikedace 
and loach minnow were listed. Although the Forest Service has made 
significant progress on some stream enhancements (Fossil Creek, Blue 
River), the multiple-use mission and limited staffing and resources has 
limited measureable on-the-ground success, and the status of these 
species has continued to decline.
    Spikedace and loach minnow are currently listed as threatened under 
the Act and therefore are afforded the protections of the Act. Special 
rules were promulgated for spikedace and loach minnow in 1986, which 
prohibit taking of the species, except under certain circumstances in 
accordance with applicable State fish and wildlife conservation laws 
and regulations. Violations of the special rules are considered 
violations of the Act (50 CFR 17.44(p) for spikedace and 50 CFR 
17.44(q) for loach minnow). As a result of the special rules for 
spikedace and loach minnow, the AGFD is issuing scientific collecting 
permits. This authority was granted at 50 CFR 17.44(p) for spikedace 
and 50 CFR 17.44(q) for loach minnow. This is confirmed through Arizona 
Commission Order 40 and New Mexico special permit (19 New Mexico 
Administrative Code 33.6.2).
    Under section 7 of the Act, Federal agencies must insure that any 
action they authorize, fund, or carry out is not likely to jeopardize 
the continued existence of any endangered or threatened species or 
result in the adverse modification or destruction of designated 
critical habitat. The Service promulgated regulations extending take 
prohibitions under section 9 for endangered species to threatened 
species. Prohibited actions under section 9 include, but are not 
limited to, take (i.e., harass, harm, pursue, hunt, shoot, wound, kill, 
trap, capture, or collect, or attempt to engage in such activity). 
Critical habitat designation alerts the public that the areas 
designated as critical habitat are important for the future recovery of 
the species, as well as invoking the review of these areas under 
section 7 of the Act with regard to any possible Federal actions in 
that area.
    Section 10 of the Act allows for the permitting of take in the 
course of otherwise lawful activities by private entities, and may 
involve habitat conservation plans which can ultimately benefit 
spikedace or loach minnow. The habitat conservation plan prepared by 
Salt River Project is expected to benefit spikedace and loach minnow in 
the Verde River.
Summary of Factor D
    In summary, prohibitions against taking the species have been in 
place for decades, but these prohibitions have limited ability to 
address the numerous habitat impacts, particularly water diversion and 
the distribution and abundance of nonnative fishes, affecting spikedace 
and loach minnow. Therefore, we find that the spikedace and loach 
minnow are threatened by the inadequacy of existing regulatory 
mechanisms.

E. Other Natural or Manmade Factors Affecting the Species' Continued 
Existence

Nonnative Fishes
    As described under Factor C above, nonnative fishes pose a 
significant threat to Gila River basin native fishes, including 
spikedace and loach minnow (Minckley 1985, pp. 1, 68; Williams et al. 
1985, pp. 3, 17-20; Minckley and Deacon 1991, pp. 15-17). Competition 
with nonnative fish species is considered a primary threat to spikedace 
and loach minnow (predation by nonnative fish species is discussed 
under Factor C). The effects of nonnative fish species are often 
exacerbated by changes in flow regimes or declines in habitat 
conditions associated with water developments, as discussed above, and 
should be considered against the backdrop of historical habitat 
degradation that has occurred over time (Minckley and Meffe 1987, pp. 
94, 103; Rinne 1991, p. 12). Stefferud and Rinne (1996b, p. 25) note 
that a long history of water development and diversion coupled with 
nonnative fish introductions has resulted in few streams in Arizona 
retaining their native fish communities. Using the Gila River as an 
example, Propst et al. (1988, p. 67) note that natural (e.g., drought) 
and human-induced (e.g., flow level reductions through irrigation 
diversion) factors combined to reduce loach minnow abundance in the 
Gila River. They note that where canyon habitat would normally continue 
to contain surface flows and suitable habitat for loach minnow, the 
establishment of nonnative fishes in canyon reaches has reduced their 
suitability as habitat for the minnow. Minckley and Douglas (1991, pp. 
7-17) concluded that, for fishes native to the Southwest, the 
combination of changes in stream discharge patterns and nonnative fish

[[Page 66493]]

introductions have reduced the range and numbers of all native species 
of fish, and has led to extinction of some.
    As with many fish in the West, spikedace and loach minnow lacked 
exposure to a wider range of species, so that they seem to lack the 
competitive abilities and predator defenses developed by fishes from 
regions where more species are present (Moyle 1986, pp. 28-31; Douglas 
et al. 1994, pp. 9-10). As a result, the native western fish fauna is 
significantly impacted by interactions with nonnative species. The 
introduction of more aggressive and competitive nonnative fish has led 
to significant losses of spikedace and loach minnow (Douglas et al. 
1994, pp. 14-17).
    The aquatic ecosystem of the central Gila River basin has 
relatively small streams with warm water and low gradients, and many of 
the native aquatic species are small. Therefore, the primary threat to 
native fishes comes from small, nonnative fish species (Deacon et al. 
1964, pp. 385, 388). Examples of this are the impacts of mosquitofish 
and red shiner, which may compete with, or predate upon, native fish in 
the Gila River basin (Meffe 1985, pp. 173, 177-185; Douglas et al. 
1994, pp. 1, 13-17).
    Nonnative fishes known to occur within the historical range of 
spikedace and loach minnow in the Gila River basin include channel 
catfish, flathead catfish, red shiner, fathead minnow, green sunfish, 
largemouth bass, smallmouth bass, rainbow trout, western mosquitofish, 
carp, warmouth (Lepomis gulosus), bluegill, yellow bullhead, black 
bullhead, and goldfish (Miller 1961, pp. 373-394; Nico and Fuller 1999, 
pp. 16, 21-24; Clark 2001, p. 1; AGFD 2004, Bahm and Robinson 2009b, p. 
3). Additionally, as discussed above, parasites introduced incidentally 
with nonnative species may jeopardize spikedace and loach minnow 
populations. For spikedace and loach minnow, every habitat that has not 
been renovated or protected by barriers has at least six nonnative fish 
species present, at varying levels of occupation. In addition, occupied 
habitats have also been invaded by nonnative crayfish (Orconectes 
virilis) (Taylor et al. 1996, p. 31; Carter et al. 2007, p. 4; Robinson 
and Crowder 2009, p. 3; Robinson et al. 2009b, p. 4). Crayfish are 
known to eat eggs, especially those bound to the substrate (Dorn and 
Mittlebach 2004, p. 2135), as is the case for spikedace and loach 
minnow. Additionally, crayfish cause decreases in macroinvertebrates, 
amphibians, and fishes (Hanson et al. 1990, p. 69; Lodge et al. 2000, 
p. 11). Several of the nonnative species now in spikedace and loach 
minnow habitats arrived there since the species were listed, such as 
red shiner in Aravaipa Creek (Stefferud and Reinthal 2005, p. 51) and 
Asian tapeworm in the middle Gila River.
    Interference competition occurs with species such as red shiner. 
Nonnative red shiners compete with spikedace for suitable habitats, as 
the two species occupy essentially the same habitat types. The red 
shiner has an inverse distribution pattern in Arizona to spikedace 
(Minckley 1973, p. 138). Where the two species occur together, there is 
evidence of displacement of spikedace to less suitable habitats than 
previously occupied (Marsh et al. 1989, pp. 67, 107). As a result, if 
red shiners are present, suitable habitat for spikedace is reduced. In 
addition, the introduction of red shiner and the decline of spikedace 
have occurred simultaneously (Minckley and Deacon 1968, pp. 1427-1428; 
Douglas et al. 1994, pp. 13, 16-17). The red shiner was introduced in 
the mainstem Colorado River in the 1950s, spreading upstream to south-
central Arizona by 1963, and by the late 1970s eastward into New 
Mexico. Spikedace disappeared at the same time and in the same 
progressively upstream direction, likely as a result of interactions 
with red shiner and in response to impacts of various water 
developments (Minckley and Deacon 1968, pp. 1427-1428; Minckley and 
Deacon 1991, pp. 7, 15; Douglas et al. 1994, pp. 13-17).
    One study focused on potential impacts of red shiner on spikedace 
in three areas: (1) Portions of the Gila River and Aravaipa Creek 
having only spikedace; (2) a portion of the Verde River where spikedace 
and red shiner co-occurred for three decades; and (3) a portion of the 
Gila River where red shiner invaded areas and where spikedace have 
never been recorded. The study indicated that, for reaches where only 
spikedace were present, spikedace displayed a preference for slower 
currents and smaller particles in the substrate than were generally 
available throughout the Gila River and Aravaipa Creek systems. Where 
red shiner occur in the Verde River, the study showed that red shiner 
occupied waters that were generally slower with smaller particle sizes 
in the substrate than were, on average, available in the system. The 
study concludes that spikedace, where co-occurring with red shiner, 
move into currents swifter than those selected when in isolation, while 
red shiner occupy the slower habitat, whether alone or with spikedace 
(Douglas et al. 1994, pp. 14-16). Red shiners are known to occur in the 
Verde River (Minckley 1993, p. 10; Jahrke 1999, pp. 2-7; Bahm and 
Robinson 2009b, pp. 3-5), Aravaipa Creek (P. Reinthal, University of 
Arizona, pers. comm. 2008; Reinthal 2009, pp. 1-2), Blue River (ASU 
2004, multiple reports; ASU 2005, multiple reports), and Gila River 
(Minckley 1973, pp. 136-137; Marsh et al. 1989, pp. 12-13; Propst et 
al. 2009, pp. 14-18).
    As with spikedace, exploitive competition also appears to occur 
between red shiner and loach minnow. Red shiners occur in all places 
known to be formerly occupied by loach minnow, and are absent or rare 
in places where loach minnow persists. Because of this, red shiner has 
often been implicated in the decline of loach minnow. Loach minnow 
habitat is markedly different than that of red shiner, so interaction 
between the two species is unlikely to cause shifts in habitat use by 
loach minnow (Marsh et al. 1989, p. 39). Instead, studies indicate that 
red shiner move into voids left when native fishes such as loach minnow 
are extirpated due to habitat degradation in the area (Bestgen and 
Propst 1986, p. 209). Should habitat conditions improve and the habitat 
once again become suitable for loach minnow, the presence of red shiner 
may preclude occupancy of loach minnow, although the specific mechanism 
of this interaction is not fully understood.
    Prior to 1960, the Glenwood-Pleasanton reach of the Gila River 
supported a native fish assemblage of eight different species. Post-
1960, four of these species became uncommon, and ultimately three of 
them were extirpated. In studies completed between 1961 and 1980, it 
was determined that loach minnow was less common than it had been, 
while the diversity of the nonnative fish community had increased in 
comparison to the pre-1960 period. Following 1980, red shiner, fathead 
minnow, and channel catfish were all regularly collected. Drought and 
diversions for irrigation resulted in a decline in habitat quality, 
with canyon reaches retaining most habitat components for native 
species. However, establishment of nonnative fishes in the canyon 
reaches has reduced the utility of these areas for native species 
(Propst et al. 1988, pp. 51-56).
    Western mosquitofish were introduced outside of their native range 
to help control mosquitoes. Because of their aggressive and predatory 
behavior, mosquitofish may negatively affect populations of small 
fishes through predation and competition (Courtenay and Meffe 1989, pp. 
320-324).

[[Page 66494]]

Introduced mosquitofish have been particularly destructive to native 
fish communities in the American West, where they have contributed to 
the elimination or decline of populations of federally endangered and 
threatened species, such as the Gila topminnow (Poeciliopsis 
occidentalis occidentalis) (Courtenay and Meffe 1989, pp. 323-324).
    Pilger et al. (2010, p. 312) found that the generalist feeding 
strategy of small-bodied nonnative fishes could further affect native 
fishes through competition, particularly if there is a high degree of 
overlap in habitat use. In their study on the upper Gila River, they 
determined that the diets of nonnative, small-bodied fishes and all age 
groups of native fishes overlapped, so that the presence of both 
juvenile and adult nonnative species could pose a competitive threat to 
native fishes (Pilger et al. 2010, p. 311).
    Restoration efforts have led to limited success in removing large-
bodied predators, but the small-bodied competitors present more of a 
challenge. In the desert Southwest, the habitat conditions are so 
limited that native fish reintroductions can occur only in those areas 
where the competition and predation of nonnative fishes can be 
physically precluded, such as above a fish barrier.

Drought

    The southwestern United States is currently experiencing drought 
conditions (University of Nebraska-Lincoln 2010, p. 1). Drought 
conditions are reported as severe to extreme for the watersheds within 
the Verde River, San Pedro River, Bonita Creek, Eagle Creek, Blue 
River, and San Francisco River subbasins in Arizona (Arizona Department 
of Water Resources 2009, p. 1). Portions of New Mexico are also 
considered abnormally dry, but not in areas currently occupied by 
spikedace and loach minnow (University of Nebraska-Lincoln 2010, p. 1). 
While spikedace and loach minnow have survived many droughts in their 
evolutionary histories, the present status of these species and their 
habitats are so degraded that the effects of the drought are more 
difficult for the species to withstand. In some areas of spikedace and 
loach minnow habitat, drought results in lower streamflow, and 
consequently warmer water temperatures beyond the species' tolerance 
limits, and more crowded habitats with higher levels of predation and 
competition. In other areas, drought reduces flooding, that would 
normally rejuvenate habitat and tend to reduce populations of some 
nonnative species, which are less adapted to the large floods of 
southwestern streams (Minckley and Meffe 1987, pp. 94, 104; Stefferud 
and Rinne 1996a, p. 80). The conjunction of drought with ongoing 
habitat loss and alteration; increased predation, competition, and 
disease from nonnative species; the uncertainties associated with 
climate change; and the general loss of resiliency in highly altered 
aquatic ecosystems have had negative consequences for spikedace and 
loach minnow populations.
Genetics
    Each remaining population of spikedace is genetically distinct. 
Genetic distinctiveness in the Verde River and Gila River fishes 
indicates that these populations have been historically isolated. The 
center of the spikedace's historical distribution is permanently 
altered, and the remaining populations are isolated and represent the 
fringes of the formerly occupied range. Isolation of these populations 
has important ramifications for the overall survival of the species. 
Loss of any population may be permanent, as there is little ability to 
repopulate isolated areas, due largely to habitat alterations in areas 
between remaining populations (Propst et al. 1986, pp. 38, 86). No 
genetic exchange is possible between the remaining populations of 
spikedace without human assistance. In addition, because genetic 
variation is important to the species' fitness and adaptive capability, 
losses of genetic variation represent a threat to the species (Meffe 
and Carroll 1997, pp. 162-172).
    Spikedace believed to remain in the upper Verde River are 
genetically different than those that were translocated to Fossil 
Creek; however, there is a minimal opportunity for the two populations 
to interbreed due to the length of the river between the two occupied 
areas. While the Verde River supports many of the habitat features for 
spikedace, it currently supports a high number of nonnative species 
that compete with, and prey on, spikedace. We anticipate that, until 
extensive management takes place, spikedace in the two areas will 
remain isolated. The spikedace translocation in Fossil Creek has been 
in place for approximately 2 years. It is not known if that 
translocation effort will succeed.
    As with spikedace, each remaining population of loach minnow is 
genetically distinct. Genetic subdivision into three geographic regions 
indicates that gene flow has been low but not historically absent 
(Tibbets 1993, pp. 22-24, 33). The center of the loach minnow's 
historical distribution is permanently gone, and the remaining 
populations are isolated and represent the fringes of the formerly 
occupied range. Isolation of these populations has important 
ramifications for the overall survival of the species. Loss of any 
population may be permanent, as there is little ability to repopulate 
isolated areas, due largely to habitat alterations in areas between 
remaining populations (Propst et al. 1988, p. 65). No genetic exchange 
is likely between the remaining populations of loach minnow without 
human assistance. In addition, because genetic variation is important 
to the species' fitness and adaptive change, losses of genetic 
variation represent a threat to the species' ability to adapt and 
persist, and further compromise their continued existence (Meffe and 
Carroll 1997, pp. 162-172).
Climate Conditions
    Climate conditions have contributed to the status of the spikedace 
and loach minnow now and will likely continue into the foreseeable 
future. While floods may benefit the species, habitat drying affects 
the occurrence of natural events, such as fire, drought, and forest 
die-off, and increases the chances of disease and infection.
    Climate simulations of Palmer Drought Severity Index (PSDI) (a 
calculation of the cumulative effects of precipitation and temperature 
on surface moisture balance) for the Southwest for the periods of 2006-
2030 and 2035-2060 predict an increase in drought severity with surface 
warming. Additionally, drought still increases during wetter 
simulations because the effect of heat-related moisture loss (Hoerling 
and Eicheid 2007, p. 19). Annual mean precipitation is likely to 
decrease in the Southwest as well as the length of snow season and snow 
depth (IPCC 2007, p. 887). Most models project a widespread decrease in 
snow depth in the Rocky Mountains and earlier snowmelt (IPCC 2007, p. 
891). Exactly how climate change will affect precipitation is less 
certain, because precipitation predictions are based on continental-
scale general circulation models that do not yet account for land use 
and land cover change effects on climate or regional phenomena. 
Consistent with recent observations in changes from climate, the 
outlook presented for the Southwest predicts warmer, drier, drought-
like conditions (Seager et al. 2007, p. 1181; Hoerling and Eischeid 
2007, p. 19). A decline in water resources with or without climate 
change will be a significant factor in the compromised watersheds of 
the desert southwest.

[[Page 66495]]

Summary of Factor E
    The small and declining spikedace and loach minnow populations make 
these species susceptible to natural environmental variability, 
including climate conditions such as drought. The high level of 
nonnative fish species competing for food resources and spawning 
conditions will exacerbate the compromised conditions where spikedace 
and loach minnow can occur. These native fishes are unable to maintain 
a competitive edge in areas where resources are already limited, and 
these resources are likely to become more limited due to water 
developments and drought. The demands on water resources, decreases in 
precipitation, and increases in temperatures are likely to further 
limit the areas where spikedace or loach minnow can persist. Therefore, 
we find that the spikedace and loach minnow are threatened by other 
natural or manmade factors.

Available Conservation Measures

    Conservation measures provided to spikedace and loach minnow under 
the Act include several reintroduction and augmentation projects. Some 
of these projects have already begun; others are in the planning stage. 
Project planning is underway for renovation efforts in Blue River and 
Spring Creek in Arizona. Other recovery actions include reintroduction 
or translocation of spikedace into streams within its historical range. 
In 2007, translocations included 210 spikedace into Hot Springs Canyon, 
210 spikedace into Redfield Canyon, and 124 spikedace into Fossil 
Creek. Monitoring and augmentation with 500 additional spikedace each 
at Hot Springs and Redfield and 600 additional spikedace at Fossil 
Creek occurred at these sites in 2008. In 2008, 448 spikedace were 
reintroduced into Bonita Creek, Arizona. Spikedace were also 
reintroduced into the San Francisco River in New Mexico. Augmentation 
and monitoring will occur at these sites as well. Monitoring conducted 
at each of these sites will be used to determine if populations 
ultimately become self-sustaining at these new locations.
    Several translocation projects for loach minnow are also in the 
planning stages. These projects may occur with or without construction 
of fish barriers. Loach minnow may also benefit from the Blue River and 
Spring Creek renovation projects mentioned above.
    Additional recovery actions include translocations or 
reintroduction of loach minnow into streams within its historical 
range. In 2007, translocations included 205 loach minnow into Hot 
Springs Canyon, 205 loach minnow into Redfield Canyon, and 124 loach 
minnow into Fossil Creek. Monitoring and augmentation with 1,000 
additional loach minnow each at Hot Springs and Redfield canyons and 
2,004 additional loach minnow at Fossil Creek occurred in 2008. In 
2008, 678 loach minnow were translocated into Bonita Creek, Arizona. 
Augmentation and monitoring will occur at this site as well. Monitoring 
conducted at each of these sites will be used to determine if 
populations ultimately become self-sustaining at these new locations.
    The AGFD and Bureau of Reclamation continue to fund equipment and 
staff to run the Bubbling Ponds Native Fish Research Facility through 
the Gila River Basin Native Fishes Conservation Program (formerly known 
as the Central Arizona Project Fund Transfer Program). Salt River 
Project's habitat conservation plan was signed in 2008, and is expected 
to benefit both the spikedace and the loach minnow in the Verde River 
watershed. Also in 2008, AGFD staff managed original source stock and 
their progeny at the Bubbling Ponds facility, totaling 740 Gila River 
spikedace, 1,650 Aravaipa Creek spikedace, 670 Blue River loach minnow, 
and 3,250 Aravaipa Creek loach minnow. Plans are underway to bring in 
stock from every extant population of loach minnow, including those in 
the San Francisco River, the three forks of the Gila River, the upper 
Gila River in New Mexico, and Eagle and the Black River system in 
Arizona. Bubbling Ponds will serve as a refuge for some populations, 
and as a captive breeding facility for others, depending on the status 
of the population and availability of translocation sites.

Proposed Determination

    As required by the Act, we considered the five factors in assessing 
whether the spikedace and loach minnow are endangered or threatened 
throughout all or a significant portion of their range. We carefully 
assessed the best scientific and commercial information available 
regarding reclassification of the spikedace and the loach minnow from 
threatened to endangered. We believe there are many threats to both 
species, including habitat loss and modifications (Factor A) caused by 
historical and ongoing land uses such as water diversion and pumping, 
livestock grazing, and road construction. However, competition with, or 
predation by, nonnative species, such as channel and flathead catfish, 
green sunfish, and red shiner, is likely the largest remaining threat 
to the species (Factors C and E). Existing regulatory mechanisms 
(Factor D) have not proven adequate to halt the decline of spikedace or 
loach minnow since the time of their listing as threatened species. In 
addition, the warmer, drier, drought-like conditions predicted to occur 
due to climate change (Factor E) will further reduce available 
resources for spikedace and loach minnow.
    In 1991, we completed a 5-year review for spikedace and loach 
minnow in which we determined that the species' status was very 
precarious and that a change in status from threatened to endangered 
was warranted. Since that time, although some recovery actions have 
occurred, the majority of the areas historically occupied by spikedace 
and loach minnow have seen a shift from a predominance of native fishes 
to a predominance of nonnative fishes. The low numbers of spikedace and 
loach minnow, their isolation in tributary waters, drought, ongoing 
water demands, and other threats indicate that the species are now in 
danger of extinction throughout their ranges.
    We determined in 1994 that reclassifying spikedace and loach minnow 
to endangered status was warranted but precluded (59 FR 35303, July 11, 
1994), and restated this conclusion on January 8, 2001 (66 FR 1295). We 
reanalyzed the determination each year in our Candidate Notice of 
Review, and determined that reclassification to endangered is 
warranted, with the most recent Candidate Notice of Review published on 
November 9, 2009 (74 FR 57804). Based on this information, as well as 
the above review of the best scientific and commercial information 
available, we find that both species meet the definition of endangered 
species under the Act, and propose that spikedace and loach minnow be 
reclassified as endangered.
    If we finalize the reclassification of spikedace and loach minnow 
to endangered status, we would remove the special rules for these 
species at 50 CFR 17.44(p) and 17.44(q), respectively. Special rules 
apply only to threatened species; therefore, if spikedace and loach 
minnow were listed as endangered, these special rules would no longer 
apply.

Critical Habitat

Background

    Critical habitat is defined in section 3 of the Act as:
    (i) The specific areas within the geographical area occupied by the 
species, at the time it is listed in accordance with the Act, on which 
are

[[Page 66496]]

found those physical or biological features:
    (I) Essential to the conservation of the species and
    (II) Which may require special management considerations or 
protection; and
    (ii) Specific areas outside the geographical area occupied by the 
species at the time it is listed, upon a determination that such areas 
are essential for the conservation of the species.
    Conservation, as defined under section 3 of the Act, means to use 
and the use of all methods and procedures that are necessary to bring 
an endangered or threatened species to the point at which the measures 
provided under the Act are no longer necessary. Such methods and 
procedures include, but are not limited to, all activities associated 
with scientific resources management such as research, census, law 
enforcement, habitat acquisition and maintenance, propagation, live 
trapping, and transplantation, and, in the extraordinary case where 
population pressures within a given ecosystem cannot be otherwise 
relieved, may include regulated taking.
    Critical habitat receives protection under section 7 of the Act 
through the prohibition against Federal agencies carrying out, funding, 
or authorizing actions that are likely to result in the destruction or 
adverse modification of critical habitat. Section 7(a)(2) requires 
consultation on Federal actions that may affect critical habitat. The 
designation of critical habitat does not affect land ownership or 
establish a refuge, wilderness, reserve, preserve, or other 
conservation area. Such designation does not allow the government or 
public to access private lands. Such designation does not require 
implementation of restoration, recovery, or enhancement measures. Where 
a landowner seeks or requests Federal agency funding or authorization 
for an action that may affect a listed species or critical habitat, the 
consultation requirements of section 7(a)(2) would apply, but even in 
the event of a destruction or adverse modification finding, the 
obligation of the Federal agency and the applicant is not to restore or 
recover the species, but to implement reasonable and prudent 
alternatives to avoid destruction or adverse modification of critical 
habitat.
    For inclusion in a critical habitat designation, the habitat within 
the geographical area occupied by the species at the time it was listed 
must contain the physical and biological features (PBFs) essential to 
the conservation of the species, and be included only if those features 
may require special management considerations or protection. Critical 
habitat designations identify, to the extent known using the best 
scientific and commercial data available, habitat areas that provide 
essential life cycle needs of the species (areas on which are found the 
PBFs laid out in the appropriate quantity and spatial arrangement for 
the conservation of the species). Under the Act and regulations at 50 
CFR 424.12, we can designate critical habitat in areas outside the 
geographical area occupied by the species at the time it is listed only 
when we determine that those areas are essential for the conservation 
of the species and that designation limited to those areas occupied at 
the time of listing would be inadequate to ensure the conservation of 
the species.
    Section 4 of the Act requires that we designate critical habitat on 
the basis of the best scientific and commercial data available. 
Further, our Policy on Information Standards Under the Endangered 
Species Act (published in the Federal Register on July 1, 1994 (59 FR 
34271)), the Information Quality Act (section 515 of the Treasury and 
General Government Appropriations Act for Fiscal Year 2001 (Pub. L. 
106-554; H.R. 5658)), and our associated Information Quality 
Guidelines, provide criteria, establish procedures, and provide 
guidance to ensure that our decisions are based on the best scientific 
data available. They require our biologists, to the extent consistent 
with the Act and with the use of the best scientific data available, to 
use primary and original sources of information as the basis for 
recommendations to designate critical habitat.
    When determining which areas should be designated as critical 
habitat, our primary source of information is generally developed 
during the listing process for the species. Additional information 
sources may include the recovery plan for the species, articles in 
peer-reviewed journals, conservation plans developed by States and 
counties, scientific status surveys and studies, biological 
assessments, or other unpublished materials and expert opinion or 
personal knowledge.
    Habitat is often dynamic, and species may move from one area of a 
river system to another over time. Furthermore, we recognize that 
critical habitat designated at a particular point in time may not 
include all of the habitat areas that we may later determine are 
necessary for the recovery of the species. For these reasons, a 
critical habitat designation does not signal that habitat outside the 
designated area is unimportant or may not be required for recovery of 
the species.
    Areas that are important to the conservation of the species, but 
are outside the critical habitat designation, will continue to be 
subject to conservation actions we implement under section 7(a)(1) of 
the Act. Areas that support populations are also subject to the 
regulatory protections afforded by the section 7(a)(2) jeopardy 
standard, as determined on the basis of the best available scientific 
information at the time of the agency action. Federally funded or 
permitted projects affecting listed species outside their designated 
critical habitat areas may still result in jeopardy findings in some 
cases. Similarly, critical habitat designations made on the basis of 
the best available information at the time of designation will not 
control the direction and substance of future recovery plans, habitat 
conservation plans (HCPs), or other species conservation planning 
efforts if new information available at the time of these planning 
efforts calls for a different outcome.

Physical and Biological Features (PBFs)

    In accordance with section 3(5)(A)(i) and 4(b)(1)(A) of the Act and 
the regulations at 50 CFR 424.12, in determining which areas within the 
geographical area occupied at the time of listing to propose as 
critical habitat, we consider the physical and biological features 
essential to the conservation of the species which may require special 
management considerations or protection. These include, but are not 
limited to:
    (1) Space for individual and population growth and for normal 
behavior;
    (2) Food, water, air, light, minerals, or other nutritional or 
physiological requirements;
    (3) Cover or shelter;
    (4) Sites for breeding, reproduction, or rearing (or development) 
of offspring; and
    (5) Habitats that are protected from disturbance or are 
representative of the historic, geographical, and ecological 
distributions of a species.
    We considered the specific PBFs essential to the conservation of 
the species and in the appropriate quantity and spatial arrangement for 
the conservation of the species. We derived the specific PBFs from the 
biological needs of spikedace and loach minnow.

[[Page 66497]]

Space for Individual and Population Growth and for Normal Behavior

Spikedace

    Microhabitats. Habitat occupied by spikedace can be broken down 
into smaller, specialized habitats called microhabitats. These 
microhabitats vary by stream, by season, and by species' life stage. 
Studies on habitat use have been completed on the Gila River in New 
Mexico, and the Verde River and Aravaipa Creek in Arizona. Generally, 
spikedace occupy moderate to large perennial streams at low elevations 
over substrates (river bottom material) of sand, gravel, and cobble 
(Barber and Minckley 1966, p. 31; Propst et al. 1986, pp. 3, 12; Rinne 
and Kroeger 1988, p. 1). Occupied streams are typically of low gradient 
(Barber et al. 1970, p. 10; Rinne and Kroeger 1988, p. 2; Rinne 1991, 
pp. 8-12; Rinne and Stefferud 1996, p. 17), and less than 1 meter (m) 
(3.28 feet (ft)) in depth (Propst et al. 1986, p. 41; Minckley and 
Marsh 2009, p. 155).
    Larval spikedace occur most frequently in slow-velocity water near 
stream margins or along pool edges. Most larvae are found over sand 
substrates. Juvenile spikedace tend to be found over a greater range of 
water velocities than larvae, but still in shallow areas. Juvenile 
spikedace occupy areas with a gravel or sand substrate, although some 
have been found over cobble substrates as well. Larvae and juveniles 
may occasionally be found in quiet pools or backwaters (e.g., pools 
that are connected with, but out of, the main river channel) (Sublette 
et al. 1990, p. 138).
    Adult spikedace occur in the widest range of flow velocities. They 
are typically associated with shear zones (areas within a stream where 
more rapidly flowing water abuts water moving at slower velocities), 
downstream of sand bars, and in eddies or small whirlpools along 
downstream margins of riffles (those shallow portions of the stream 
with rougher, choppy water). Adult spikedace are found in shallow water 
over predominantly gravel-dominated substrates (Propst et al. 1986, p. 
40; Rinne 1991, pp. 8-12; Rinne and Stefferud 1997, p. 21; Rinne and 
Deacon 2000, p. 106; Rinne 2001, p. 68), but also over cobble and sand 
substrates (Minckley and Marsh 2009, p. 155; Rinne and Kroeger 1988, p. 
3; Sublette et al. 1990, p. 138).
    In addition to substrate type, the amount of embeddedness (filling 
in of spaces by fine sediments) is also important to spikedace. 
Spikedace more commonly occur in areas with low to moderate amounts of 
fine sediment and substrate embeddedness, which is important for the 
healthy development of eggs. Spawning has been observed in areas with 
sand and gravel beds and not in areas where fine materials smaller than 
sand coats the sand or gravel substrate. Additionally, low to moderate 
fine sediments ensure that eggs remain well-oxygenated and will not 
suffocate due to sediment deposition (Propst et al. 1986, p. 40).
    Water temperatures of occupied spikedace habitat vary with time of 
year. Water temperatures have been collected at Aravaipa Creek, and on 
the Gila River in the Forks area and at the Cliff-Gila Valley. Summer 
water temperatures were between 19.3 degrees Celsius ([deg]C) (66.7 
degrees Fahrenheit ([deg]F)) (Gila River, Forks Area) and 27 [deg]C 
(80.6 [deg]F) (Aravaipa Creek). Winter water temperatures ranged 
between 8.9 [deg]C (48.0 [deg]F) at Aravaipa Creek and 11.7 [deg]C 
(53.1 [deg]F) in the Cliff-Gila Valley (Barber and Minckley 1966, p. 
316; Barber et al. 1970, pp. 11, 14; Propst et al. 1986, p. 57).
    Recent studies by the University of Arizona focused on temperature 
tolerances of spikedace. In the study, fish were acclimated to a given 
temperature, and then temperatures were increased by 1 [deg]C (1.8 
[deg]F) per day until test temperatures were reached. The study 
determined that no spikedace survived exposure of 30 days at 34 or 36 
[deg]C (93.2 or 96.8 [deg]F), and that 50 percent mortality occurred 
after 30 days at 32.1 [deg]C (89.8 [deg]F). In addition, growth rate 
was slowed at 32 [deg]C (89.6 [deg]F), as well as at the lower test 
temperatures of 10 and 4 [deg]C (50 and 39.2 [deg]F). Multiple 
behavioral and physiological changes were observed, indicating the fish 
became stressed at 30, 32, and 33 [deg]C (86, 89.6 and 91.4 [deg]F) 
treatments. The study concludes that temperature tolerance in the wild 
may be lower due to the influence of additional stressors, including 
disease, predation, competition, or poor water quality. Survival of 
fish in the fluctuating temperature trials in the study likely 
indicates that exposure to higher temperatures for short periods during 
a day would be less stressful to spikedace. The study concludes that 
100 percent survival of spikedace at 30 [deg]C (86 [deg]F) in the 
experiment suggests that little juvenile or adult mortality would occur 
due to thermal stress if peak water temperatures remain at or below 
that level (Bonar et al. 2005, pp. 7-8, 29-30).
    Spikedace occupy streams with low to moderate gradients (Propst et 
al. 1986, p. 3; Rinne and Stefferud 1997, p. 14; Stefferud and Rinne 
1996, p. 21; Sublette et al. 1990, p. 138). Specific gradient data are 
generally lacking, but the gradient of occupied portions of Aravaipa 
Creek and the Verde River varied between approximately 0.3 to < 1.0 
percent (Barber et al. 1970, p. 10; Rinne and Kroeger 1988, p. 2; Rinne 
and Stefferud 1997, p. 14).
    Table 1 compares specific parameters of habitat occupied by 
spikedace at various ages as identified through studies completed to 
date. Studies on flow velocity in occupied spikedace habitat have been 
completed on the Gila River, Aravaipa Creek, and the Verde River 
(Barber and Minckley 1966, p. 321; Minckley 1973, p. 114; Anderson 
1978, p. 17; Schreiber 1978, p. 4; Turner and Tafanelli 1983, pp. 15-
16; Propst et al. 1986, pp. 39-41; Rinne and Kroeger 1988, p. 1; Hardy 
et al. 1990, pp. 19-20, 39; Sublette et al. 1990, p. 138; Rinne 1991, 
pp. 9-10; Rinne 1999, p. 6).

                        Table 1--Habitat Parameters for Varying Life Stages of Spikedace
----------------------------------------------------------------------------------------------------------------
                                                Larvae                 Juveniles                  Adults
----------------------------------------------------------------------------------------------------------------
Flow Velocity in centimeters per       8.4 (3.3)..............  16.8 (6.6).............  23.3-70.0 (9.2-27.6).
 second (inches per second).
Depth in centimeters (inches)........  3.0-48.8 (1.2-19.2)....  3.0-45.7 (1.2-18.0)....  6.1-42.7 (2.4-16.8).
Gradient (percent)...................  No data................  No data................  0.3 to < 1.0.
Substrate............................  Primarily sand, with     Primarily gravel, with   Sand, gravel, cobble,
                                        some over gravel or      some sand and cobble.    and low amounts of
                                        cobble.                                           fine sediments.
----------------------------------------------------------------------------------------------------------------

    In studies on the Gila River, there were seasonal shifts in 
microhabitats used, involving depth or velocity, depending on the study 
site. It is believed that seasonal shifts in microhabitat use reflect 
selection by spikedace for particular microhabitats. In the cold 
season, when their metabolic rate decreases, spikedace near the Forks

[[Page 66498]]

area on the Gila River seek protected areas among the cobble of stream 
channel margins, where water is shallower and warmer. In other areas 
such as the Cliff-Gila Valley, cobbled banks for protection were 
generally not available, but slow-velocity areas in the lee of gravel 
bars and riffles were common, and spikedace shifted to these protected 
areas of slower velocity during the cold season. Seasonal changes in 
microhabitat preference by spikedace are not entirely understood, and 
additional study is needed (Propst et al. 1986, pp. 47-49).
    Studies indicate a geographic variation in the portion of the 
stream used by spikedace. On the Verde River, outside of the April to 
June breeding season, 80 percent of the spikedace collected used run 
and glide habitat. For this study, a glide was defined as a portion of 
the stream with a lower gradient (0.3 percent), versus a run which had 
a slightly steeper gradient (0.3-0.5 percent) (Rinne and Stefferud 
1996, p. 14). In contrast, spikedace in the Gila River were most 
commonly found in riffle areas of the stream with moderate to swift 
currents (Anderson 1978, p. 17) and some run habitats (J.M. Montgomery 
1985, p. 21), as were spikedace in Aravaipa Creek (Barber and Minckley 
1966, p. 321).
    Flooding. In part, suitable habitat conditions are maintained by 
flooding. Periodic flooding appears to benefit spikedace in three ways: 
(1) Removing excess sediment from some portions of the stream; (2) 
removing nonnative fish species from a given area; and (3) increasing 
prey species diversity. Items 2 and 3 will be addressed in greater 
detail below.
    Flooding in Aravaipa Creek has resulted in the transport of heavier 
loads of sediments, such as cobble, gravel, and sand, that are 
deposited where the stream widens, gradient flattens, and velocity and 
turbulence decreases. Dams formed by such deposition can temporarily 
cause water to back up and break into braids downstream of the dam. The 
braided areas provide excellent nurseries for larval and juvenile 
fishes (Velasco 1997, pp. 28-29).
    On the Gila River in New Mexico, flows fluctuate seasonally with 
snowmelt, causing spring pulses and occasional floods, and late-summer 
or monsoonal rains produce floods of varying intensity and duration. 
These high flows likely rejuvenate spikedace spawning and foraging 
habitat (Propst et al. 1986, p. 3). Floods likely benefit native fish 
by breaking up embedded bottom materials (Mueller 1984, p. 355). A 
study of the Verde River analyzed the effects of flooding in 1993 and 
1995, finding that the floods either stimulated spawning, enhanced 
recruitment of three native species, or eliminated one of the nonnative 
fish species (Stefferud and Rinne 1996a, p. 80).
    In summary, based on the best scientific and commercial information 
available for spikedace, we have developed the following ranges in 
habitat parameters, as follows:
     Shallow water generally less than 1 m (3.3 ft) in depth;
     Slow to swift flow velocities between 5 and 80 cm per 
second (sec) (1.9 and 31.5 in. per sec);
     Glides, runs, riffles, the margins of pools and eddies, 
and backwater components;
     Sand, gravel, and cobble substrates with low or moderate 
amounts of fine sediment and substrate embeddedness, as maintained by a 
natural, unregulated flow regime that allows for periodic flooding or, 
if flows are modified or regulated, a flow regime that allows for 
adequate river functions, such as flows capable of transporting 
sediments;
     Low gradients of less than approximately one percent;
     Water temperatures in the general range of 8 to 28 [deg]C 
(46.4 to 82.4 [deg]F); and
     Elevations below 2,100 m (6,890 ft).

Loach Minnow

    Microhabitat. The best scientific and commercial information 
available indicates that, in general, loach minnow live on the bottom 
of small to large streams or rivers with low gradients within shallow, 
swift, and turbulent riffles. They are also known to occupy pool, 
riffle, and run habitats in some areas. They live and feed among clean, 
loose, gravel-to-cobble substrates. Their reduced air bladder (the 
organ that aids in controlling a fish's ability to float without 
actively swimming) allows them to persist in high-velocity habitats 
with a minimal amount of energy, and they live in the interstitial 
spaces (openings) between rocks (Anderson and Turner 1977, pp. 2, 6-7, 
9, 12-13; Barber and Minckley 1966, p. 315; Lee et al. 1980, p. 365; 
Britt 1982, pp. 10-13, 29-30; J.M. Montgomery 1985, p. 21; Marsh et al. 
2003, p. 666; Minckley 1981, p. 165; Propst et al. 1988, p. 35; Rinne 
1989, p. 109; Velasco 1997, p. 28; Sublette et al. 1990, p. 187; AGFD 
1994, pp. 1, 5-11; Bagley et al. 1995, pp. 11, 13, 16, 17, 22; Rinne 
2001, p. 69; Minckley and Marsh 2009, p. 174). Loach minnow are 
sometimes found in or near filamentous (threadlike) algae, which are 
attached to the stream substrates (Anderson and Turner 1977, p. 5; Lee 
et al. 1980, p. 365; Minckley 1981, p. 165; Sublette et al. 1990, p. 
187; Marsh and Minckley 2009, p. 174).
    Microhabitats used by loach minnow vary by life stage and stream. 
Adult loach minnow occupy a broad range of water velocities, with the 
majority of adults occurring in swift flows. Their eggs are adhesive, 
and are placed on the undersurfaces of rocks in the same riffles that 
they themselves occupy. After hatching, larval loach minnow move from 
the rocks under which they were spawned to areas with slower velocities 
than the main stream, typically remaining in areas with significantly 
slower velocities than juveniles and adults. Larval loach minnow occupy 
areas that are shallower and significantly slower than areas where eggs 
are found (Propst et al. 1988, p. 37; Propst and Bestgen 1991, p. 32). 
Juvenile loach minnow generally occur in areas where velocities are 
similar to those used by adults, and that have higher flow velocities 
than those occupied by larvae (Propst et al. 1988, pp. 36-37).
    Substrate is an important component of loach minnow habitat. 
Studies in Aravaipa Creek and the Gila River indicate that loach minnow 
prefer cobble and large gravel, avoiding areas dominated by sand or 
fine gravel. This may be because loach minnow maintain a relatively 
stationary position on the bottom of a stream in flowing water. An 
irregular bottom, such as that created by cobble or larger gravels, 
creates pockets of lower water velocities around larger rocks where 
loach minnow can remain stationary with less energy expenditure (Turner 
and Tafanelli 1983, pp. 24-25). In the Gila and San Francisco rivers, 
the majority of loach minnow captured occurred in the upstream portion 
of a riffle, rather than in the central and lower sections of the 
riffle, where loose materials are more likely to fall out of the water 
column and settle on the stream bottom. This is likely due to the 
availability of interstitial spaces in the cobble-rubble substrate, 
which became filled with sediment more quickly in the central and lower 
sections of a riffle (Propst et al. 1984, p. 12).
    Varying substrates are used during different life stages of loach 
minnow. Adults occur over cobble and gravel, and place their eggs in 
these areas. Larval loach minnow are found where substrate particles 
are smaller than those used by adults. Juvenile loach minnow occupy 
areas with substrates of larger particle size than larvae. Generally, 
adults exhibited a narrower preference for depth and substrate than did 
juveniles, and were associated with gravel to cobble substrates within 
a narrower range of depths (Propst et al.

[[Page 66499]]

1988, pp. 36-39; Propst and Bestgen 1991, pp. 32-33).
    Loach minnow have a fairly narrow range in temperature tolerance, 
and their upstream distributional limits in some areas may be linked to 
low winter stream temperature (Propst et al. 1988, p. 62). Suitable 
temperature regimes appear to be fairly consistent across geographic 
areas. Studies of Aravaipa Creek, East Fork White River, the San 
Francisco River, and the Gila River determined that loach minnow were 
present in areas with water temperatures in the range of 9 to 22 [deg]C 
(48.2 to 71.6 [deg]F) (Britt 1982, p. 31; Propst et al. 1988, p. 62; 
Leon 1989, p. 1; Propst and Bestgen 1991, p. 33; Vives and Minckley 
1990, p. 451).
    Recent studies by the University of Arizona focused on temperature 
tolerances of loach minnow. In one study, fish were acclimated to a 
given temperature, and then temperatures were increased by 1 [deg]C 
(1.8 [deg]F) per day until test temperatures were reached. The study 
determined that no loach minnow survived for 30 days at 32 [deg]C (89.6 
[deg]F), and that 50 percent mortality occurred after 30 days at 30.6 
[deg]C (87.1 [deg]F). In addition, growth rate slowed at 28 and 30 
[deg]C (82.4 and 86.0 [deg]F) compared to growth at 25 [deg]C (77 
[deg]F), indicating that loach minnow were stressed at sublethal 
temperatures. Survival of fish in the fluctuating temperature trials of 
the study likely indicates that exposure to higher temperatures for 
short periods during a day would be less stressful to loach minnow. The 
study concludes that temperature tolerance in the wild may be lower due 
to the influence of additional stressors, including disease, predation, 
competition, or poor water quality. The study concludes that since 100 
percent survival of loach minnow at 28 [deg]C (82.4 [deg]F) was 
observed, that little juvenile or adult mortality would occur due to 
thermal stress if peak water temperatures remain at or below that level 
(Bonar et al. 2005, pp. 6-8, 28, 33).
    Gradient may influence the distribution and abundance of loach 
minnow. In studies of the San Francisco River, Gila River, Aravaipa 
Creek, and the Blue River, loach minnow occurred in stream reaches 
where the gradient was generally low, ranging from 0.3 to 2.2 percent 
(Rinne 1989, p. 109; Rinne 2001, p. 69).
    Table 2 compares specific parameters of microhabitats occupied by 
loach minnow at various ages as identified through studies completed to 
date. Studies on habitat occupied by loach minnow have been completed 
on the Gila River, Tularosa River, San Francisco River, Aravaipa Creek, 
Deer Creek, and Eagle Creek (Barber and Minckley 1966, p. 321; Britt 
1982, pp. 1, 5, 10-12, 29; Turner and Tafanelli 1983, pp. 15-20, 26; 
Propst et al. 1984, pp. 7-12; Propst et al. 1988, pp. 32, 36-39; Rinne 
1989, pp. 111-113, 116; Propst and Bestgen 1991, p. 32; Vives and 
Minckley 1990, pp. 451-452; Propst and Bestgen 1991, pp. 32-33; Velasco 
1997, pp. 5-6; Marsh et al. 2003, p. 666).

                       Table 2--Habitat Parameters for Varying Life Stages of Loach Minnow
----------------------------------------------------------------------------------------------------------------
                                          Egg               Larvae             Juveniles            Adults
----------------------------------------------------------------------------------------------------------------
Flow Velocity in centimeters per  3.0-91.4 (1.2-      0.0-48.8 (0.0-      3.0-85.3 (1.2-      0.0-79.2 (0.0-
 second (inches per second).       36.0).              19.2).              33.6).              31.2).
Depth in centimeters (inches)...  3.0-30.5 (1.2-12).  3.0-45.7 (1.2-      6.1-42.7 (2.4-      6.1-45.7 (2.4-
                                                       8.0).               16.8).              18.0).
Substrate.......................  Large gravel to     No data...........  No data...........  Gravel to cobble.
                                   rubble.
----------------------------------------------------------------------------------------------------------------

    There are some differences in microhabitats occupied by loach 
minnow in different areas. Studies completed in New Mexico determined 
that there were significant differences in water velocities occupied 
among the three study sites, with the mean velocities at 37.4 (Tularosa 
River), 56.3 (Forks area of the Gila River) and 60.5 cm per second 
(Cliff-Gila Valley site on the Gila River). Differences in water depth 
were not as pronounced, however. Much of the variation in microhabitat 
utilization may be explained by habitat availability, as the compared 
streams varied in size (Propst et al. 1988, pp. 37-43).
    Flooding. Flooding also plays an important role in habitat 
suitability for loach minnow. In areas where substantial diversions 
(structures created to divert water to pools for pumping from the 
stream) or impoundments have been constructed, loach minnow are less 
likely to occur (Propst et al. 1988, pp. 63-64; Propst and Bestgen 
1991, p. 37). This is in part due to habitat changes caused by the 
construction of the diversions, and in part due to the reduction of 
beneficial effects of flooding on loach minnow habitat. Flooding 
appears to positively affect loach minnow population dynamics by 
resulting in higher recruitment (reproduction and survival of young) 
and by decreasing the abundance of nonnative fishes (addressed further 
below) (Stefferud and Rinne 1996b, p. 1).
    Flooding also cleans, rearranges, and rehabilitates important 
riffle habitat (Propst et al. 1988, pp. 63-64). Flooding allows for the 
scouring of sand and gravel in riffle areas, which reduces the degree 
of embeddedness of cobble and boulder substrates (Britt 1982, p. 45). 
Typically, sediment is carried along the bed of a stream and deposited 
at the downstream, undersurface side of cobbles and boulders. Over 
time, this can result in the filling of cavities created under cobbles 
and boulders (Rinne 2001, p. 69). Flooding removes the extra sediment, 
and cavities created under cobbles by scouring action of the flood 
waters provides enhanced spawning habitat for loach minnow.
    Studies on the Gila, Tularosa, and San Francisco rivers found that 
flooding is primarily a positive influence on native fish, and 
apparently had a positive influence on the relative abundance of loach 
minnow (Britt 1982, p. 45). Rather than following a typical pattern of 
winter mortality and population decline, high levels of loach minnow 
recruitment occurred after the flood, and loach minnow relative 
abundance remained high through the next spring. Flooding enhanced and 
enlarged loach minnow habitat, resulting in a greater survivorship of 
individuals through winter and spring (Propst et al. 1988, p. 51). 
Similar results were observed on the Gila and San Francisco rivers 
following flooding in 1978 (Britt 1982, p. 45).
    In summary, based on the best scientific and commercial information 
available for loach minnow, we have developed generalized ranges in 
habitat parameters within streams or rivers, as follows:
     Shallow water generally less than 1 m (3.3 ft) in depth;
     Slow to swift flow velocities between 0 and 80 cm per sec 
(0.0 and 31.5 in. per sec);
     Pools, runs, riffles and rapids;
     Sand, gravel, cobble, and rubble substrates with low or 
moderate amounts of fine sediment and substrate embeddedness, as 
maintained by a

[[Page 66500]]

natural, unregulated flow regime that allows for periodic flooding or, 
if flows are modified or regulated, flow regime that allow for adequate 
river functions, such as flows capable of transporting sediments;
     Water temperatures in the general range of 8 to 25 [deg]C 
(46.4 to 77 [deg]F);
     Low stream gradients of less than approximately 2.5 
percent; and
     Elevations below 2,500 m (8,202 ft).

Food, Water, Air, Light, Minerals, or Other Nutritional or 
Physiological Requirements

Spikedace

    Food. Spikedace are active, highly mobile fish that visually 
inspect drifting materials both at the surface and within the water 
column. Gustatory inspection, or taking the potential prey items into 
the mouth before either swallowing or rejecting it, is also common 
(Barber and Minckley 1983, p. 37). Prey body size is small, typically 
ranging from 2 to 5 mm (0.08 to 0.20 in) long (Anderson 1978, p. 36).
    Stomach content analysis of spikedace determined that mayflies, 
caddisflies, true flies (Order Diptera), stoneflies, and dragonflies 
(Order Odonata) are all potential prey items. In one Gila River study, 
the frequency of occurrence was 71 percent for mayflies, 34 percent for 
true flies, and 25 percent for caddisflies (Propst et al. 1986, p. 59). 
A second Gila River study of four samples determined that total food 
volume was composed of 72.7 percent mayflies, 17.6 percent caddisflies, 
and 4.5 percent true flies (Anderson 1978, pp. 31-32). At Aravaipa 
Creek, mayflies, caddisflies, true flies, stoneflies, and dragonflies 
were all prey items for spikedace, as were some winged insects and 
plant materials (Schreiber 1978, pp. 12-16, 29, 35-37). Barber and 
Minckley (1983, pp. 34-38) found that spikedace at Aravaipa Creek also 
consumed ants and wasps (Order Hymenoptera), spiders (Order Areneae), 
beetles (Order Coleoptera), true bugs, and water fleas (Order 
Cladocera).
    Spikedace diet varies seasonally (Barber and Minckley 1983, pp. 34-
38). Mayflies dominated stomach contents in July, but declined in 
August and September, increasing in importance again between October 
and June. When mayflies were available in lower numbers, spikedace 
consumed a greater variety of foods, including true bugs, true flies, 
beetles, and spiders.
    Spikedace diet varies with age class as well. Young spikedace fed 
on a diversity of small-bodied invertebrates occurring in and on 
sediments along the margins of the creek. True flies were found most 
frequently, but water fleas and aerial adults of aquatic and 
terrestrial insects also provide significant parts of the diet. As 
juveniles grow and migrate into the swifter currents of the channel, 
mayfly nymphs (invertebrates between the larval and adult life stages, 
similar to juveniles) and adults increase in importance (Barber and 
Minckley 1983, pp. 36-37).
    Spikedace are dependent on aquatic insects for sustenance, and the 
production of the aquatic insects consumed by spikedace occurs mainly 
in riffle habitats (Propst et al. 1986, p. 59). Barber and Minckley 
(1983, pp. 36-37, 40) found that spikedace in pools had eaten the least 
diverse food, while those from riffles contained a greater variety of 
taxa, indicating that the presence of riffles in good condition and 
abundance help to ensure that a sufficient number and variety of prey 
items will continue to be available for spikedace.
    Aquatic invertebrates that constitute the bulk of the spikedace 
diet have specific habitat parameters of their own. Mayflies occur 
primarily in fresh water with an abundance of oxygen. Spikedace consume 
mayflies from the genus Baetidae (Schreiber 1978, p. 36), which are 
free-ranging species of rapid waters that maintain themselves in 
currents by clinging to pebbles. Spikedace also consumed individuals 
from two other mayfly genera (Heptageniidae and Ephemerellidae), which 
are considered ``clinging species,'' as they cling tightly to stones 
and other objects and may be found in greatest abundance in crevices 
and on the undersides of stones (Pennak 1978, p. 539). The importance 
of gravel and cobble substrates is illustrated by the fact that the 
availability of these prey species, which make up the bulk of the 
spikedace diet, requires these surfaces to persist.
    The availability of food for spikedace is affected by flooding. The 
onset of flooding corresponds with an increased diversity of food 
items, as inflowing flood water carries terrestrial invertebrates, such 
as ants, bees, and wasps, into aquatic areas (Barber and Minckley 1983, 
p. 39).
    Water. As a purely aquatic species, spikedace are entirely 
dependent on streamflow habitat for all stages of their life cycle. 
Therefore, perennial flows are an essential feature. Areas with 
intermittent flows may serve as connective corridors between occupied 
or seasonally occupied habitat through which the species may move when 
the habitat is wetted.
    In addition to water quantity, water quality is important to 
spikedace. Water with no or low levels of pollutants is essential for 
the survival of spikedace. For spikedace, pollutants such as copper, 
arsenic, mercury, cadmium, human and animal waste products, pesticides, 
suspended sediments, ash, and gasoline or diesel fuels should not be 
present at high levels (D. Baker, Service, pers. comm. 2005). In 
addition, for freshwater fish, dissolved oxygen should generally be 
greater than 3.5 cubic centimeters per liter (cc per l) (Bond 1979, p. 
215). Below this, some stress to fish may occur.
    Fish kills have been documented within the range of the spikedace, 
including on the San Francisco River (Rathbun 1969, pp. 1-2) and the 
San Pedro River (Eberhardt 1981, pp. 1-4, 6-9, 11-12, 14, 16, and 
Tables 2-8). Occupancy by spikedace at the San Francisco River site is 
less certain, but spikedace were present in the Gila River upstream of 
its confluence with the San Francisco. Spikedace were present in the 
San Pedro River up through 1969 within the area affected by the Cananea 
Mine spill, which extended 97 km (60 mi) north of the United States/
Mexico border (Eberhardt 1981, p. 3). All aquatic life within this 97-
km (60-mi) stretch was killed between 1977 and 1979, and no spikedace 
records are known after that time. For both the San Francisco and San 
Pedro rivers, leaching ponds associated with copper mines released 
waters into the streams, resulting in elevated levels of toxic 
chemicals. For the San Pedro River, this included elevated levels of 
iron, copper, manganese, and zinc. Both incidents resulted in die-offs 
of species inhabiting the streams. Eberhardt (1981, pp. 1, 3, 9, 10, 
14-15) noted that no bottom-dwelling aquatic insects, live fish, or 
aquatic vegetation of any kind were found in the area affected by the 
spill. Rathbun (1969, pp. 1-2) reported similar results for the San 
Francisco River. As detailed above under the threats discussion, spills 
or discharges have occurred in the Gila River and affected streams 
within the watersheds of spikedace, including the Gila River, San 
Francisco River, San Pedro River, and some of their tributaries 
(Environmental Protection Agency 1997, pp. 24-67; Arizona Department of 
Environmental Quality 2000, p. 6; Church et al. 2005, p. 40; Arizona 
Department of Environmental Quality 2007, p. 1).
    Based on the information above, we identify an appropriate prey 
base and water quality to be a PBF for spikedace, as follows:
     An abundant aquatic insect food base consisting of 
mayflies, true flies,

[[Page 66501]]

black flies, caddisflies, stoneflies, and dragonflies;
     Streams with no or no more than low levels of pollutants;
     Perennial flows, or interrupted stream courses that are 
periodically dewatered but that serve as connective corridors between 
occupied or seasonally occupied habitat and through which the species 
may move when the habitat is wetted;
     Streams with a natural, unregulated flow regime that 
allows for periodic flooding or, if flows are modified or regulated, a 
flow regime that allows for adequate river functions, such as flows 
capable of transporting sediments.

Loach Minnow

    Food. Loach minnow are opportunistic, feeding on riffle-dwelling 
larval mayflies, black flies, and true flies, as well as from larvae of 
other aquatic insect groups such as caddisflies and stoneflies. Loach 
minnow in the Gila, Tularosa, and San Francisco rivers consumed 
primarily true flies and mayflies, with mayfly nymphs being an 
important food item throughout the year. Mayfly nymphs constituted the 
most important food item throughout the year for adults studied on the 
Gila and San Francisco Rivers, while larvae of true flies (insects of 
the order Diptera) were most common in the winter months (Propst et al. 
1988, p. 27; Propst and Bestgen 1991, p. 35). In Aravaipa Creek, loach 
minnow consumed 11 different prey items, including mayflies, 
stoneflies, caddisflies, and true flies. Mayflies constituted the 
largest percentage of their diet during this study except in January, 
when true flies made up 54.3 percent of the total food volume 
(Schreiber 1978, pp. 40-41).
    Loach minnow consume different prey items during their various life 
stages. Both larvae and juveniles primarily consumed true flies, which 
constituted approximately 7 percent of their food items in one year, 
and 49 percent the following year in one study. Mayfly nymphs were also 
an important dietary element at 14 percent and 31 percent during a one-
year study. Few other aquatic macroinvertebrates were consumed (Propst 
et al. 1988, p. 27). In a second study, true fly larvae and mayfly 
nymphs constituted the primary food of larval and juvenile loach minnow 
(Propst and Bestgen 1991, p. 35).
    The availability of pool and run habitats affects availability of 
prey species. While most of the food items of loach minnow are riffle 
species, two are not, including true fly larvae and mayfly nymphs. 
Mayfly nymphs, at times, made up 17 percent of the total food volume of 
loach minnow in a study at Aravaipa Creek (Schreiber 1978, pp. 40-41). 
The presence of a variety of habitat types is, therefore, important to 
the persistence of loach minnow in a stream, even though they are 
typically associated with riffles.
    Water Quality. Water, with no or low pollutant levels, is important 
for the conservation of loach minnow. For loach minnow, waters should 
have no more than low levels of pollutants, such as copper, arsenic, 
mercury, cadmium, human and animal waste products, pesticides, 
suspended sediments, and gasoline or diesel fuels (D. Baker, Service, 
pers. comm. 2005). In addition, for freshwater fish, dissolved oxygen 
should generally be greater than 3.5 cc per l (Bond 1979, p. 215). 
Below this, some stress to the fish may occur.
    Fish kills associated with previous mining accidents, as well as 
other contaminants issues, are detailed under the spikedace discussion 
above. These incidents occurred within the historical range of the 
loach minnow. As with spikedace, loach minnow were known to occur in 
the area affected by the Cananea Mine spill up through 1961. All 
aquatic life within the affected area was killed between 1977 and 1979, 
and no loach minnow records are known after that time. On the San 
Francisco River, loach minnow are known to have occurred in the general 
area of the spill in the 1980s and 1990s (ASU 2002). Additional spills 
or discharges have occurred in the Gila River and affected streams 
within the watersheds occupied by loach minnow, including the Gila 
River, San Francisco River, San Pedro River, and some of their 
tributaries (Environmental Protection Agency 1997, pp. 24-67; Arizona 
Department of Environmental Quality 2000, p. 6; Church et al. 2005, p. 
40; Arizona Department of Environmental Quality 2007, p. 1).
    Based on the information above, we identify an appropriate prey 
base and water quality to be a PBF for the loach minnow, as follows:
     An abundant aquatic insect food base consisting of 
mayflies, true flies, black flies, caddisflies, stoneflies, and 
dragonflies;
     Streams with no or no more than low levels of pollutants;
     Perennial flows, or interrupted stream courses that are 
periodically dewatered but that serve as connective corridors between 
occupied or seasonally occupied habitat and through which the species 
may move when the habitat is wetted; and
     Streams with a natural, unregulated flow regime that 
allows for periodic flooding or, if flows are modified or regulated, a 
flow regime that allows for adequate river functions, such as flows 
capable of transporting sediments.
Cover or Shelter
    Spikedace. No specific information on habitat parameters used 
specifically for cover and shelter is available for spikedace. 
Therefore, we have not identified any specific physical and biological 
features specific to cover and shelter for spikedace.
    Loach Minnow. As noted above, adult loach minnow are sometimes 
associated with filamentous algae, which may serve as a protective 
cover (Anderson and Turner 1977, p. 5; Lee et al. 1980, p. 365; 
Minckley 1981, p. 165; Sublette et al. 1990, p. 187; Marsh and Minckley 
2009, p. 174).
    Loach minnow adults place their adhesive eggs on the undersides of 
rocks, with the rock serving as protective cover. Probst et al. (1988, 
p. 21) found that the rocks used were typically elevated from the 
surface of the streambed on the downstream side, with most rocks 
flattened and smooth-surfaced. Adult loach minnow remain with the eggs, 
so that the rock serves as a protective cover for them as well (Propst 
et al. 1988, pp. 21-25, 36-39).

Sites for Breeding, Reproduction, or Rearing (or Development) of 
Offspring

Spikedace

    Suitable sites. Spikedace occur in specific habitat during the 
breeding season, with female and male spikedace becoming segregated. 
Females occupy pools and eddies, while males occupy riffles flowing 
over sand and gravel beds in water approximately 7.9 to 15.0 cm (3.1 to 
5.9 in) deep. Females then enter the riffles occupied by the males 
before eggs are released into the water column (Barber et al. 1970, pp. 
11-12).
    Spikedace eggs are adhesive and develop among the gravel and cobble 
of the riffles following spawning. Spawning in riffle habitat ensures 
that the eggs are well oxygenated and are not normally subject to 
suffocation by sediment deposition due to the swifter flows found in 
riffle habitats. However, after the eggs have adhered to the gravel and 
cobble substrate, excessive sedimentation could cause suffocation of 
the eggs (Propst et al. 1986, p. 40).
    Larval and juvenile spikedace occupy peripheral portions of streams 
that have slower currents (Anderson 1978, p. 17; Propst et al. 1986, 
pp. 40-41). Gila River studies found larval spikedace in velocities of 
8.4 cm per second (3.3 in. per sec) while juvenile spikedace occupy 
areas with velocities of approximately 16.8 cm per second (6.6 in. per 
sec) (Propst et al. 1986, p. 41).

[[Page 66502]]

    Once they emerge from the gravel of the spawning riffles, spikedace 
larvae disperse to stream margins where water velocity is very slow or 
still. Larger larval and juvenile spikedace (those fish 25.4 to 35.6 mm 
(1.0 to 1.4 in) in length) occurred over a greater range of water 
velocities than smaller larvae, but still occupied water depths of less 
than 32.0 cm (12.6 in) (Propst et al. 1986, p. 40). Juveniles and 
larvae are also occasionally found in quiet pools or backwaters (e.g., 
pools that are connected with, but out of, the main river channel) 
lacking streamflow (Sublette et al. 1990, p. 138).
    During a study on the Gila River, 60 percent of spikedace larvae 
were found over sand-dominated substrates, while 18 percent were found 
over gravel, and an additional 18 percent found over cobble-dominated 
substrates. While 45 percent of juvenile spikedace were found over sand 
substrates, an additional 45 percent of the juveniles were found over 
gravel substrates, with the remaining 10 percent associated with 
cobble-dominated substrates. Juveniles occupy a wider range in flow 
velocities than larvae (0.0 to 57.9 cm per second (22.8 in. per 
second)), but occurred at similar depths as larvae (Propst et al. 1986, 
pp. 40-41).
    As noted above, excessive sedimentation can lead to suffocation of 
eggs. Clean substrates are therefore essential for successful breeding. 
Both flooding and unaltered flow regimes are essential for maintenance 
of suitable substrates. As noted above under habitat requirements, 
periodic flooding appears to benefit spikedace by removing excess 
sediment from some portions of the stream, breaking up embedded bottom 
materials, or rearranging sediments in ways that restore suitable 
habitats. Flooding may also stimulate spawning or enhance recruitment 
(Mueller 1984, p. 355; Propst et al. 1986, p. 3; Stefferud and Rinne 
1996a, p. 80; Minckley and Meffe 1987, pp. 99, 100; Rinne and Stefferud 
1997, pp. 159, 162; Velasco 1997, pp. 28-29).
    Streams in the southwestern United States have a wide fluctuation 
in flows and some are periodically dewatered. While portions of stream 
segments included in this proposed designation may experience dry 
periods, they are still considered important because the spikedace is 
adapted to stream systems with fluctuating water levels. While they 
cannot persist in dewatered areas, spikedace will use these areas as 
connective corridors between occupied or seasonally occupied habitat 
when they are wetted. Areas that serve as connective corridors are 
those ephemeral or intermittent stream segments that connect two or 
more other perennial stream segments.
    Therefore, based on the information above, we identify the 
following to be PBFs for spikedace:
     Sand, gravel, and cobble substrates;
     Riffle habitat;
     Slower currents along stream margins with appropriate 
stream velocities for larvae;
     Appropriate water depths for larvae and juvenile 
spikedace;
     Flow velocities that encompass the range of 8.5 cm per sec 
(3.3 in. per sec) to 57.9 cm per sec (22.8 in. per sec); and
     Streams with a natural, unregulated flow regime that 
allows for periodic flooding or, if flows are modified or regulated, a 
flow regime that allows for adequate river functions, such as flows 
capable of transporting sediments.

Loach Minnow

    Adult loach minnow attach eggs to the undersurfaces of rocks in the 
same riffles in which they are typically found. In studies conducted on 
the Gila River, water velocities in these areas ranged from 3.0 to 91.4 
cm per second (36.0 in. per second). The majority of rocks with 
attached eggs were found in water flowing at approximately 42.7 cm per 
second (16.8 in. per second). The range of depths in which rocks with 
eggs attached were found was 3.0 to 30.5 cm (1.2 to 12 in), with the 
majority found between 6.1 and 21.3 cm (2.4 and 8.4 in) (Propst et al. 
1988, pp. 36-39).
    Loach minnow larvae occupy shallower and slower water than eggs. In 
Gila River studies, larvae occurred in flow velocities averaging 7.9 cm 
per second (3.1 in. per second), and in depths between 3.0 to 45.7 cm 
(1.2 to 18 in). Juveniles occurred in areas with higher velocities, 
ranging between 35.1 and 85.3 cm per second (13.8 and 33.6 in. per 
second). Juveniles occurred in slightly deeper water of approximately 
6.1 to 42.7 cm (2.4 to 16.8 in) (Propst et al. 1988, pp. 36-39).
    As noted above under general habitat requirements, flooding is 
important in maintaining loach minnow habitat, including habitats used 
for breeding. Flooding reduces embeddedness of cobble and boulder 
substrates under which eggs are placed (Britt 1982, p. 45).
    The construction of water diversions have reduced or eliminated 
riffle habitat in many stream reaches, resulting in pool development. 
Loach minnow are generally absent in stream reaches affected by 
impoundments. While the specific factors responsible for this are not 
known, it is likely related to modification of thermal regimes, 
habitat, food base, or discharge patterns (Propst et al. 1988, p. 64; 
Minckley 1973, pp. 1-11).
    Therefore, based on the information above, we identify the 
following to be PBFs for loach minnow:
     Cobble substrates;
     Riffle habitats;
     Slower currents along stream margins with appropriate 
stream velocities for larvae;
     Appropriate water depths for larvae and juvenile loach 
minnow;
     Flow velocities that encompass the range of 6.1 to 42.7 cm 
(2.4 to 16.8 in); and
     Streams with a natural, unregulated flow regime that 
allows for periodic flooding or, if flows are modified or regulated, a 
flow regime that allows for adequate river functions, such as flows 
capable of transporting sediments.

Habitats Protected From Disturbance or Representative of the 
Historical, Geographical, and Ecological Distributions of the Species

Spikedace

    Nonnative aquatic species. One of the primary reasons for the 
decline of native species is the presence of nonnative fishes, as 
described above under Factors C and E above. Interactions with 
nonnative fishes can occur in the form of interference competition 
(e.g., predation) or exploitive competition (competition for 
resources), and introduced species are considered a primary factor in 
the decline of native species (Anderson 1978, pp. 50-51; Miller et al. 
1989, p. 1; Lassuy 1995, p. 392). Multiple nonnative fish species are 
now present in the range of spikedace and loach minnow. In addition, 
nonnative parasites are also present.
    Flooding may help to reduce the threat presented by nonnative 
species. Minckley and Meffe (1987, pp. 99-100) found that flooding, as 
part of a natural flow regime, may temporarily remove nonnative fish 
species, which are not adapted to flooding patterns in the Southwest. 
Thus flooding consequently removes the competitive pressures of 
nonnative fish species on native fish species which persist following 
the flood. Minckley and Meffe (1987, pp. 99-100) studied the 
differential response of native and nonnative fishes in seven 
unregulated and three regulated streams or stream reaches that were 
sampled before and after major flooding and noted that fish faunas of 
canyon-bound reaches of unregulated streams invariably shifted from a 
mixture of native and nonnative fish species to predominantly, and in 
some cases exclusively, native fishes after

[[Page 66503]]

large floods. Samples from regulated systems indicated relatively few 
or no changes in species composition due to releases from upstream dams 
at low, controlled volumes. However, during emergency releases, effects 
to nonnative fish species were similar to those seen with flooding on 
unregulated systems. There is some variability in fish response to 
flooding. Some nonnative species, such as smallmouth bass and green 
sunfish, appear to be partially adapted to flooding, and often reappear 
in a few weeks (Minckley and Meffe 1987, p. 100).
    The information presented above indicates the detrimental effects 
of interference and exploitive competition with nonnative species to 
spikedace, as well as the issues presented by the introduction of 
nonnative parasites. Therefore, based on this information, we identify 
the necessary PBFs for spikedace to be:
     Habitat devoid of nonnative aquatic species, or habitat in 
which nonnative aquatic species are at levels that allow persistence of 
spikedace.

Loach Minnow

    As with spikedace (discussed above), interference and exploitive 
competition with nonnative species can be detrimental to loach minnow. 
Interference competition, in the form of predation, may result from 
interactions between loach minnow and nonnative channel and flathead 
catfish, while exploitive competition likely occurs with red shiner. 
The discussion under Factor C above on disease and predation includes 
information on other nonnative aquatic species, such as Asian tapeworm, 
anchor worm, and Ich, which are also detrimental to loach minnow.
    The discussion under spikedace on flooding and its benefits in 
potentially minimizing threats from nonnative fishes applies to loach 
minnow as well.
    The information presented above indicates the detrimental effects 
of interference and exploitive competition with nonnative species to 
loach minnow, as well as the issues presented by the introduction of 
nonnative parasites. Therefore, based on this information, we identify 
the PBFs for loach minnow as follows:
     Habitat devoid of nonnative aquatic species, or habitat in 
which nonnative aquatic species are at levels that allow persistence of 
loach minnow; and
     Streams with a natural, unregulated flow regime that 
allows for periodic flooding or, if flows are modified or regulated, a 
flow regime that allows for adequate river functions, such as flows 
capable of transporting sediments.

Physical and Biological Features for Spikedace and Loach Minnow

    Based on the above needs and our current knowledge of the life 
history, biology, and ecology of the species and the habitat 
requirements for sustaining the essential life history functions of the 
species, we have determined that PBFs for the spikedace are:
    (1) Habitat to support all egg, larval, juvenile, and adult 
spikedace. This habitat includes perennial flows with a stream depth 
generally less than 1 m (3.3 ft), and with slow to swift flow 
velocities between 5 and 80 cm per second (1.9 and 31.5 in. per 
second). Appropriate stream microhabitat types include glides, runs, 
riffles, the margins of pools and eddies, and backwater components over 
sand, gravel, and cobble substrates with low or moderate amounts of 
fine sediment and substrate embeddedness. Appropriate habitat will have 
a low gradient of less than approximately 1.0 percent, at elevations 
below 2,100 m (6,890 ft). Water temperatures should be in the general 
range of 8.0 to 28.0 [deg]C (46.4 to 82.4 [deg]F);
    (2) An abundant aquatic insect food base consisting of mayflies, 
true flies, black flies, caddisflies, stoneflies, and dragonflies;
    (3) Streams with no or no more than low levels of pollutants;
    (4) Perennial flows, or interrupted stream courses that are 
periodically dewatered but that serve as connective corridors between 
occupied or seasonally occupied habitat and through which the species 
may move when the habitat is wetted;
    (5) No nonnative aquatic species, or levels of nonnative aquatic 
species that are sufficiently low as to allow persistence of spikedace; 
and
    (6) Streams with a natural, unregulated flow regime that allows for 
periodic flooding or, if flows are modified or regulated, a flow regime 
that allows for adequate river functions, such as flows capable of 
transporting sediments.
    Based on the above needs and our current knowledge of the life 
history, biology, and ecology of the species and the habitat 
requirements for sustaining the essential life history functions of the 
species, we have determined that PBFs for the loach minnow are:
    (1) Habitat to support all egg, larval, juvenile, and adult loach 
minnow. This habitat includes perennial flows with a stream depth of 
generally less than 1 m (3.3 ft), and with slow to swift flow 
velocities between 0 and 80 cm per second (0.0 and 31.5 in. per 
second). Appropriate microhabitat types include pools, runs, riffles, 
and rapids over sand, gravel, cobble, and rubble substrates with low or 
moderate amounts of fine sediment and substrate embeddedness. 
Appropriate habitats have a low stream gradient of less than 2.5 
percent, are at elevations below 2,500 m (8,202 ft). Water temperatures 
should be in the general range of 8.0 to 25.0 [deg]C (46.4 to 77 
[deg]F);
    (2) An abundant aquatic insect food base consisting of mayflies, 
true flies, black flies, caddisflies, stoneflies, and dragonflies;
    (3) Streams with no or no more than low levels of pollutants;
    (4) Perennial flows, or interrupted stream courses that are 
periodically dewatered but that serve as connective corridors between 
occupied or seasonally occupied habitat and through which the species 
may move when the habitat is wetted;
    (5) No nonnative aquatic species, or levels of nonnative aquatic 
species that are sufficiently low to allow persistence of loach minnow; 
and
    (6) Streams with a natural, unregulated flow regime that allows for 
periodic flooding or, if flows are modified or regulated, a flow regime 
that allows for adequate river functions, such as flows capable of 
transporting sediments.

Special Management Considerations or Protection

    When designating critical habitat, we assess whether the specific 
areas determined to be occupied at the time of listing contain the PBFs 
and may require special management considerations or protection. We 
believe each area included in this proposed designation requires 
special management and protections as described in our unit 
descriptions.
    Special management considerations for each area will depend on the 
threats to the spikedace or loach minnow, or both, in that critical 
habitat area. For example, threats requiring special management include 
nonnative fish species and the continued spread of nonnative fishes 
into spikedace or loach minnow habitat. Other threats requiring special 
management include the threat of fire, retardant application during 
fire, and excessive ash and sediment following fire. Poor water quality 
and adequate quantities of water for all life stages of spikedace and 
loach minnow threaten these fish and may require special management 
actions or protections. Improper livestock grazing can be a threat to 
spikedace and loach minnow and their habitats, although concern for 
this threat has lessened due to improved management practices. The 
construction of water diversions can

[[Page 66504]]

include increasing water depth behind diversion structures, and has 
reduced or eliminated riffle habitat in many stream reaches. In 
addition, loach minnow are generally absent in stream reaches affected 
by impoundments. While the specific factor responsible for this is not 
known, it is likely related to modification of thermal regimes, 
habitat, food base, or discharge patterns.
    We have included below in our description of each of the critical 
habitat areas for the spikedace and loach minnow a discussion of the 
threats occurring in that area requiring special management or 
protections.

Criteria Used To Identify Critical Habitat

    As required by section 4(b) of the Act, we used the best scientific 
and commercial data available in determining areas within the 
geographical area occupied at the time of listing that contain the 
features essential to the conservation of spikedace and loach minnow, 
and areas outside of the geographical areas occupied at the time of 
listing that are essential for the conservation of spikedace and loach 
minnow. Sources of data for these two species include multiple 
databases maintained by universities and State agencies for Arizona and 
New Mexico, existing recovery plans, endangered species reports (Propst 
et al. 1986, 1988), and numerous survey reports on streams throughout 
the species' range. We have also reviewed available information that 
pertains to the habitat requirements of this species. Sources of 
information on habitat requirements include existing recovery plans, 
endangered species reports, studies conducted at occupied sites and 
published in peer-reviewed articles, agency reports, and data collected 
during monitoring efforts.
    The recovery plans for spikedace and loach minnow were both 
finalized in 1991 (Service 1991a; Service 1991b), and are in need of 
revision. We are in the process of convening a recovery team for this 
purpose. In the interim, we have developed an internal preliminary 
assessment of potential steps necessary for achieving recovery of 
spikedace and loach minnow.
    The current distribution of both spikedace and loach minnow is much 
reduced from their historical distribution. We anticipate that recovery 
will require establishing populations in streams and watersheds that 
more closely approximate their historical distribution in order to 
ensure there are adequate numbers of fish in stable populations, and 
that these populations occur over a wide geographic area. This will 
help to ensure that catastrophic events, such as wildfire or 
contaminant spills, cannot simultaneously affect all known populations. 
We developed necessary steps for downlisting as well as delisting. For 
spikedace, our preliminary assessment recommends that downlisting 
criteria include that one additional stable population be established 
in either the Salt or Verde subbasin, and the number of occupied 
streams be increased from 8 (the current level) to 10 rangewide. 
Occupancy may be established through natural means (i.e., expansion by 
the fish themselves) or through translocation efforts. For delisting of 
spikedace, our preliminary assessment indicates that a stable 
population should be established in the remaining subbasin, and that 
occupied streams within the historical range of the species be 
increased to 12. In addition, the goal is to ensure that all genetic 
lineages are adequately represented in the 12 occupied streams, where 
appropriate and feasible.
    For loach minnow, our preliminary assessment recommends that, in 
order to delist the species, the number of occupied streams be 
increased from 19 (the current level) to 22, with one occupied stream 
in each of the major watersheds. For delisting, the preliminary 
assessment recommends increasing the number of occupied streams to 25, 
with at least one occupied stream in each of the major watersheds, and 
that remaining genetic lineages be adequately represented in at least 
one stream, where appropriate and feasible.
    The preliminary assessment makes other recommendations, including 
establishing protective measures for connective areas, maintaining 
captive breeding stocks, and developing plans for augmentation of 
captive breeding stock.
    Our preliminary assessment of the habitats needed for conservation 
of these species attempts to provide geographic distribution across the 
ranges of the species, represent the full ranges of habitat and 
environmental variability the species have occupied, and preserve 
existing genetic diversity. We anticipate that the final recovery plans 
developed by the Recovery Team, once formed, may vary from this 
assessment, and will likely provide additional criteria and 
prioritization of recovery actions. However, we believe that the broad 
goals used in our preliminary assessment will be similar to those for 
the recovery planning process as recovery will require expanding the 
currently contracted ranges and establishing additional populations.
    We determined that all areas proposed for designation contain the 
PBFs for spikedace or loach minnow. There are no developed areas within 
the proposed designation except for barriers constructed on streams or 
road crossings of streams, which do not remove the suitability of these 
areas for these species.
    We used the following ruleset to determine which areas to include 
within this proposal:
    (1) Evaluate the suitability of stream segments that are within the 
geographic area occupied at the time of listing and:
    (a) Retain those segments that contain sufficient PBFs to support 
life-history functions essential for the conservation of the species, 
and
    (b) Eliminate those areas that were known to be occupied at 
listing, but that no longer support any PBFs for the species or that 
have been permanently altered so that restoration is unlikely, or both.
    (2) Evaluate stream segments not known to be within the geographic 
area occupied at listing, but that are within the historical range of 
the species to determine if they are essential to the survival and 
recovery of the species. Essential areas are those that:
    (a) Serve as an extension of habitat in the unit, as existing 
habitat is insufficient to recover the species;
    (b) Expand the geographic distribution across the range of the 
species, as the current geographic distribution is reduced to 10 to 20 
percent of historical range, and concentrates fish in a few remaining 
areas that are more likely susceptible to catastrophic events; and
    (c) Connect to other occupied areas, which will enhance genetic 
exchange between populations.
    We considered the known occupancy of the area, as well as the 
suitability and level of adverse impacts to habitat within each unit. 
We believe the areas proposed provide for the conservation of the 
spikedace and the loach minnow because they include habitat for all 
extant populations, provide habitat for all known genetic lineages, and 
include habitat for connectivity and dispersal opportunities within 
units. Such opportunities for dispersal assist in maintaining the 
population structure and distribution of the two species.
    As a final step, we evaluated those stream segments retained 
through the above analysis, and refined the starting and end points by 
evaluating the presence or absence of appropriate PBFs. We selected 
upstream and downstream cutoff points to exclude areas that are highly 
degraded and are not likely restorable. For example,

[[Page 66505]]

permanently dewatered areas, permanently developed areas, or areas in 
which there was a change to unsuitable parameters (e.g., a steep 
gradient, bedrock substrate) were used to mark the start or endpoint of 
a stream segment proposed for designation. Critical habitat stream 
segments were then mapped using ArcMap (Environmental Systems Research 
Institute, Inc.), a Geographic Information Systems program.
    The areas proposed for designation as critical habitat are designed 
to provide sufficient riverine and associated floodplain area for 
breeding, non-breeding, and dispersing adult spikedace and loach 
minnow, as well as for the habitat needs for juvenile and larval stages 
of these fishes. In general, the physical and biological features of 
critical habitat for spikedace and loach minnow are contained within 
the riverine ecosystem formed by the wetted channel and the adjacent 
floodplains within 91.4 lateral m (300 lateral ft) on either side of 
bankfull stage, except where bounded by canyon walls. Areas within the 
lateral extent also contribute to the PBFs, including water quality and 
intermittent areas through which fish may move when wetted. Spikedace 
and loach minnow use the riverine ecosystem for feeding, breeding, and 
sheltering while breeding and migrating.
    This proposed designation takes into account the naturally dynamic 
nature of riverine systems and floodplains (including riparian and 
adjacent upland areas) that are an integral part of the stream 
ecosystem. For example, riparian areas are seasonally flooded habitats 
(i.e., wetlands) that are major contributors to a variety of functions 
vital to fish within the associated stream channel (Brinson et al. 
1981, pp. 2-61, 2-69, 2-72, 2-75, 2-84 through 2-85; Federal 
Interagency Stream Restoration Working Group 1998). They are 
responsible for energy and nutrient cycling, filtering runoff, 
absorbing and gradually releasing floodwaters, recharging groundwater, 
maintaining streamflow, protecting stream banks from erosion, and 
providing shade and cover for fish and other aquatic species. Healthy 
riparian and adjacent upland areas help ensure water courses maintain 
the habitat important for aquatic species (e.g., see Forest Service 
1979, pp. 18, 109, 158, 264, 285, 345; Middle Rio Grande Biological 
Interagency Team 1993, pp. 64, 89, 94; Castelle et al. 1994, pp. 279-
281), including the spikedace and loach minnow. Habitat quality within 
the mainstem river channels in the historical range of the spikedace 
and loach minnow is intrinsically related to the character of the 
floodplain and the associated tributaries, side channels, and backwater 
habitats that contribute to the key habitat features (e.g., substrate, 
water quality, and water quantity) in these reaches. We have determined 
that a relatively intact riparian area, along with periodic flooding in 
a relatively natural pattern, is important for maintaining the PBFs 
necessary for long-term conservation of the spikedace and the loach 
minnow.
    The lateral extent (width) of riparian corridors fluctuates 
considerably between a stream's headwaters and its mouth. The 
appropriate width for riparian buffer strips has been the subject of 
several studies and varies depending on the specific function required 
for a particular buffer (Castelle et al. 1994, pp. 879-881). Most 
Federal and State agencies generally consider a zone 23 to 46 m (75 to 
150 ft) wide on each side of a stream to be adequate (National Resource 
Conservation Service 1998, pp. 2-3; Moring et al. 1993, p. 204; Lynch 
et al. 1985, p. 164), although buffer widths as wide as 152 m (500 ft) 
have been recommended for achieving flood attenuation benefits (U.S. 
Army Corps 1999, pp. 5-29). In most instances, however, riparian buffer 
zones are primarily intended to reduce (i.e., buffer) detrimental 
impacts to the stream from sources outside the river channel. 
Consequently, while a riparian corridor 23 to 46 m (75 to 150 ft) in 
width may function adequately as a buffer, it is likely inadequate to 
preserve the natural processes that provide spikedace and loach minnow 
PBFs.
    The lateral extent of streams included in this proposed designation 
is 91.4 m (300 ft) to either side of bankfull stage. We believe this 
width is necessary to accommodate stream meandering and high flows, and 
in order to ensure that this proposal contains the features essential 
to the conservation of the species. Bankfull stage is defined as the 
upper level of the range of channel-forming flows, which transport the 
bulk of available sediment over time. Bankfull stage is generally 
considered to be that level of stream discharge reached just before 
flows spill out onto the adjacent floodplain. The discharge that occurs 
at bankfull stage, in combination with the range of flows that occur 
over a length of time, govern the shape and size of the river channel 
(Rosgen 1996, pp. 2-2 to 2-4; Leopold 1997, pp. 62-63, 66). The use of 
bankfull stage and 91.4 m (300 ft) on either side recognizes the 
naturally dynamic nature of riverine systems, recognizes that 
floodplains are an integral part of the stream ecosystem, and contains 
the area and associated features essential to the conservation of the 
species.
    We determined the 91.4-m (300-ft) lateral extent for several 
reasons. First, the implementing regulations of the Act require that 
critical habitat be defined by reference points and lines as found on 
standard topographic maps of the area (50 CFR 424.12(c)). Although we 
considered using the 100-year floodplain, as defined by the Federal 
Emergency Management Agency, we found that it was not included on 
standard topographic maps, and the information was not readily 
available from Federal Emergency Management Agency or from the U.S. 
Army Corps of Engineers for the areas we are proposing to designate. We 
suspect this is related to the remoteness of many of the stream reaches 
where these species occur. Therefore, we selected the 91.4-m (300-ft) 
lateral extent, rather than some other delineation, for three 
biological reasons: (1) The biological integrity and natural dynamics 
of the river system are maintained within this area (i.e., the 
floodplain and its riparian vegetation provide space for natural 
flooding patterns and latitude for necessary natural channel 
adjustments to maintain appropriate channel morphology and geometry, 
store water for slow release to maintain base flows, provide protected 
side channels and other protected areas, and allow the river to meander 
within its main channel in response to large flow events); (2) 
conservation of the adjacent riparian area also helps to provide 
important nutrient recharge and protection from sediment and 
pollutants; and (3) vegetated lateral zones are widely recognized as 
providing a variety of aquatic habitat functions and values (e.g., 
aquatic habitat for fish and other aquatic organisms, moderation of 
water temperature changes, and detritus for aquatic food webs) and help 
improve or maintain local water quality (see U.S. Army Corps of 
Engineers' Final Notice of Issuance and Modification of Nationwide 
Permits, March 9, 2000, 65 FR 12818).
    When determining critical habitat boundaries within this proposed 
rule, we made every effort to avoid including structures such as 
bridges, diversion structures, or other structures which lack suitable 
PBFs for the spikedace and loach minnow. The scope of the maps we 
prepared under the parameters for publication within the Code of 
Federal Regulations may not reflect the exclusion of such developed 
lands. Any such structures and the land under them inadvertently left 
inside critical habitat boundaries shown on the maps are excluded by 
text in this proposed rule.

[[Page 66506]]

Therefore, a Federal action involving these lands (if and when 
designated) would not trigger section 7 consultation with respect to 
critical habitat and the prohibition of destruction or adverse 
modification, unless the specific action may affect adjacent critical 
habitat. Where a developed structure is within the proposed critical 
habitat designation (e.g., paved low water crossing, a portion of a 
stream flowing under a bridge), the area would be considered to be 
proposed critical habitat if it continues to contain one or more of the 
PBFs.
    We propose eight units for designation based on sufficient PBFs 
being present to support spikedace or loach minnow life processes. Some 
segments contain all PBFs and support multiple life processes. Some 
segments contain only a portion of the PBFs necessary to support the 
spikedace or the loach minnow's particular use of that habitat.

Proposed Critical Habitat Designation

    We are proposing 1,168 km (726 mi) of streams as critical habitat 
for spikedace, and 1,141 km (709 mi) of streams as critical habitat for 
loach minnow. Of this total mileage, 874 km (543 mi) of streams are 
overlapping (i.e., proposed for designation for both species). The 
critical habitat areas we describe below constitute our current best 
assessment of areas that meet the definition of critical habitat for 
spikedace and loach minnow. The eight units we propose as critical 
habitat occur in portions of the Verde River and its tributaries; the 
Salt River and its tributaries; the San Pedro River and its 
tributaries; Bonita Creek; Eagle Creek; the San Francisco River and its 
tributaries; the Blue River and its tributaries; and the Gila River and 
its tributaries. Tables 3 and 4 show the occupied units for the 
spikedace and the loach minnow. Table 5 provides a breakdown of river 
miles by type of landowner or manager for all proposed critical habitat 
units for the spikedace and the loach minnow.

                       Table 3--Occupancy of Proposed Critical Habitat Units by Spikedace
----------------------------------------------------------------------------------------------------------------
                                          Occupied at time of                                  Translocated
            Stream segment                      listing            Currently occupied?          population
----------------------------------------------------------------------------------------------------------------
                                          Unit 1--Verde River Subbasin
----------------------------------------------------------------------------------------------------------------
Verde River mainstem..................  Yes....................  Yes....................  No.
Granite Creek.........................  No.....................  No.....................  No.
Oak Creek.............................  No.....................  No.....................  No.
Beaver and Wet Beaver Creek...........  Yes....................  No.....................  No.
West Clear Creek......................  Yes....................  No.....................  No.
Fossil Creek..........................  No.....................  Yes....................  Yes.
----------------------------------------------------------------------------------------------------------------
                                           Unit 2--Salt River Subbasin
----------------------------------------------------------------------------------------------------------------
Tonto Creek...........................  Yes....................  No.....................  No.
Greenback Creek.......................  No.....................  No.....................  No.
Rye Creek.............................  No.....................  No.....................  No.
Spring Creek..........................  No.....................  No.....................  Proposed.
Rock Creek............................  No.....................  No.....................  Proposed.
----------------------------------------------------------------------------------------------------------------
                                        Unit 3--San Pedro River Subbasin
----------------------------------------------------------------------------------------------------------------
San Pedro River.......................  Yes....................  No.....................  No.
Hot Springs Canyon....................  No.....................  Yes....................  Yes.
Bass Canyon...........................  No.....................  No.....................  No.
Redfield Canyon.......................  No.....................  Yes....................  Yes.
Aravaipa Creek........................  Yes....................  Yes....................  No.
Deer Creek............................  No.....................  No.....................  No.
Turkey Creek..........................  No.....................  No.....................  No.
----------------------------------------------------------------------------------------------------------------
                                          Unit 4--Bonita Creek Subbasin
----------------------------------------------------------------------------------------------------------------
Bonita Creek mainstem.................  No.....................  Yes....................  Yes.
----------------------------------------------------------------------------------------------------------------
                                          Unit 5--Eagle Creek Subbasin
----------------------------------------------------------------------------------------------------------------
Eagle Creek mainstem..................  Yes....................  Yes....................  No.
----------------------------------------------------------------------------------------------------------------
                                      Unit 6--San Francisco River Subbasin
----------------------------------------------------------------------------------------------------------------
San Francisco River...................  Yes....................  Yes....................  Yes.
----------------------------------------------------------------------------------------------------------------
                                           Unit 7--Blue River Subbasin
----------------------------------------------------------------------------------------------------------------
Blue River............................  No.....................  No.....................  Proposed.
Campbell Blue Creek...................  No.....................  No.....................  No.
Dry Blue Creek........................  No.....................  No.....................  No.
Little Blue Creek.....................  No.....................  No.....................  No.
Pace Creek............................  No.....................  No.....................  No.
Frieborn Creek........................  No.....................  No.....................  No.
----------------------------------------------------------------------------------------------------------------

[[Page 66507]]

 
                                           Unit 8--Gila River Subbasin
----------------------------------------------------------------------------------------------------------------
Gila River............................  Yes....................  Yes....................  No.
West Fork Gila River..................  Yes....................  Yes....................  No.
Middle Fork Gila River................  Yes....................  Yes....................  No.
East Fork Gila River..................  Yes....................  Yes....................  No.
Mangas Creek..........................  Yes....................  Yes....................  No.
----------------------------------------------------------------------------------------------------------------


                      Table 4--Occupancy of Proposed Critical Habitat Units by Loach Minnow
----------------------------------------------------------------------------------------------------------------
                                        Known to be occupied at                                Translocated
                 Unit                            listing            Currently occupied          population
----------------------------------------------------------------------------------------------------------------
                                          Unit 1--Verde River Subbasin
----------------------------------------------------------------------------------------------------------------
Verde River mainstem..................  Yes....................  No.....................  No.
Granite Creek.........................  No.....................  No.....................  No.
Oak Creek.............................  No.....................  No.....................  No.
Beaver and Wet Beaver Creek...........  Yes....................  No.....................  No.
Fossil Creek..........................  No.....................  Uncertain..............  Yes.
----------------------------------------------------------------------------------------------------------------
                                           Unit 2--Salt River Subbasin
----------------------------------------------------------------------------------------------------------------
White River mainstem..................  Yes....................  Uncertain..............  No.
East Fork White River.................  Yes....................  Uncertain..............  No.
North Fork White River................  Yes....................  Uncertain..............  No.
East Fork Black River.................  No.....................  No.....................  No.
Boneyard Creek........................  No.....................  No.....................  No.
Coyote Creek..........................  Yes....................  Yes....................  No.
----------------------------------------------------------------------------------------------------------------
                                        Unit 3--San Pedro River Subbasin
----------------------------------------------------------------------------------------------------------------
San Pedro mainstem....................  Yes....................  No.....................  No.
Hot Springs Canyon....................  No.....................  Yes....................  Yes.
Bass Canyon...........................  No.....................  No.....................  No.
Redfield Canyon.......................  No.....................  Yes....................  Yes.
Aravaipa Creek........................  Yes....................  Yes....................  No.
Deer Creek............................  Yes....................  Yes....................  No.
Turkey Creek..........................  Yes....................  Yes....................  No.
----------------------------------------------------------------------------------------------------------------
                                          Unit 4--Bonita Creek Subbasin
----------------------------------------------------------------------------------------------------------------
Bonita Creek mainstem.................  No.....................  Yes....................  Yes.
----------------------------------------------------------------------------------------------------------------
                                          Unit 5--Eagle Creek Subbasin
----------------------------------------------------------------------------------------------------------------
Eagle Creek mainstem..................  Yes....................  Yes....................  No.
----------------------------------------------------------------------------------------------------------------
                                      Unit 6--San Francisco River Subbasin
----------------------------------------------------------------------------------------------------------------
San Francisco mainstem................  Yes....................  Yes....................  No.
Tularosa River........................  Yes....................  Yes....................  No.
Negrito Creek.........................  Yes....................  Yes....................  No.
Whitewater Creek......................  Yes....................  No.....................  No.
----------------------------------------------------------------------------------------------------------------
                                           Unit 7--Blue River Subbasin
----------------------------------------------------------------------------------------------------------------
Blue River mainstem...................  Yes....................  Yes....................  No.
Campbell Blue Creek...................  Yes....................  Yes....................  No.
Dry Blue Creek........................  Yes....................  Yes....................  No.
Little Blue Creek.....................  Yes....................  No.....................  No.
Pace Creek............................  Yes....................  Yes....................  No.
Frieborn Creek........................  Yes....................  Yes....................  No.
----------------------------------------------------------------------------------------------------------------
                                           Unit 8--Gila River Subbasin
----------------------------------------------------------------------------------------------------------------
Gila River mainstem...................  Yes....................  Yes....................  No.
West Fork Gila River..................  Yes....................  Yes....................  No.
Middle Fork Gila River................  Yes....................  Yes....................  No.

[[Page 66508]]

 
East Fork Gila River..................  Yes....................  Yes....................  No.
Mangas Creek..........................  Yes....................  Yes....................  No.
----------------------------------------------------------------------------------------------------------------



                                         Table 5--Proposed Critical Habitat Units for Spikedace and Loach Minnow
                                        [Area estimates reflect all land within critical habitat unit boundaries]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                   Federal                State           Local or tribal *          Private                Total
                   Unit                    -------------------------------------------------------------------------------------------------------------
                                                Km         Mi         Km         Mi         Km         Mi         Km         Mi         Km         Mi
--------------------------------------------------------------------------------------------------------------------------------------------------------
1.........................................        146         90          4          2         11          7        112         70        273        169
2.........................................        119         74          0          0         46         28         12          7        177        109
3.........................................         89         55         17         11          4          2         50         31        160         99
4.........................................         18         11          0          0          0          0          5          3         23         14
5.........................................         21         13          0          0         27         17         27         17         75         47
6.........................................        146         91          3          2          0          0         70         44        219        137
7.........................................         93         58          0          0          0          0         14          9        107         67
8.........................................        156         97          2          1          0          0         90         56        248        154
                                           -------------------------------------------------------------------------------------------------------------
    Total.................................        788        489         26         16         88         54        380        237      1,282        796
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note: Area sizes may not sum due to rounding. Total figures for Complex 1 vary from those in the text description below. The additional stream miles
  fall within different landowner categories which were not summarized here.

    We present brief descriptions of all units, and reasons why they 
meet the definition of critical habitat for spikedace and loach minnow 
or both, below. Table 6 at the end of this section summarizes the 
criteria from the ruleset (above) under which units were included.

Unit 1: Verde River Subbasin

    Within this Verde River Subbasin, we are proposing to designate 
281.2 km (174.8 mi) on the Verde River and its tributaries Granite 
Creek, Oak Creek, Beaver and Wet Beaver Creek, West Clear Creek, and 
Fossil Creek for spikedace. For loach minnow, we are proposing to 
designate 218.2 km (135.6 mi) on the Verde River and its tributaries 
Granite Creek, Oak Creek, Beaver and Wet Beaver Creek, and Fossil 
Creek. All of the mileage included in the proposed designation for 
loach minnow is included within the proposed designation for spikedace.
    The Verde River and its tributaries included within the proposed 
designation are in Yavapai and Gila Counties, Arizona. From Sullivan 
Lake, near its headwaters, the Verde River flows for 201 km (125 mi) 
downstream to Horseshoe Reservoir. The Verde River is unique in 
comparison to many desert streams such as the Salt or Gila rivers in 
that it is free-flowing for its upper 201 km (125 mi). The Verde River 
is also perennial for that length (Sullivan and Richardson 1993, pp. 
19-21; The Nature Conservancy 2006).
    Due to the low number of remaining populations and severely 
restricted range, spikedace are at risk of extirpation from this 
watershed. Portions of this unit are known to be have been occupied at 
listing, while others have historical records or newly translocated 
populations. We determined that this area is essential to the 
conservation of both species because it contains physical habitat 
features to support the species (PBF 1), perennial streams with no or 
low levels of pollutants (PBFs 3 and 4), has an appropriate hydrologic 
regime to maintain suitable habitat characteristics (PBF 6), and 
provides suitable areas for a possible future barrier construction and 
species augmentation to support both species' recovery. Securing both 
species in this watershed will contribute significantly to the species' 
eventual recovery.
    Approximately 1.2 km (0.8 mi) of the Verde River and 0.2 km (0.1 
mi) of Beaver Creek/Wet Beaver Creek occur on lands owned by the 
Yavapai-Apache Nation. These areas will be considered for exclusion 
from the final critical habitat designation under section 4(b)(2) of 
the Act (see ``Application of Section 4(b)(2) of the Act'' section 
below for additional information).
    Spikedace and loach minnow. For both spikedace and loach minnow, we 
are including within this proposal 3.2 km (2.0 mi) of Granite Creek 
from the confluence with the Verde River upstream to an unnamed spring. 
Above the spring there are insufficient flows to maintain these 
species. There are no known records of spikedace or loach minnow from 
Granite Creek specifically, but it is within the historical range known 
to be occupied by both species. As a perennial tributary of the Verde 
River in the area with the highest species density, Granite Creek is 
considered an important expansion area for spikedace recovery. Granite 
Creek is also considered an important expansion area for loach minnow 
recovery. These portions of Granite Creek are essential to the 
conservation of both species because they contain suitable habitat for 
all life stages of spikedace and loach minnow (PBF 1); have an 
appropriate food base (PBF 2); and consist of perennial streams with no 
or low levels of pollutants (PBFs 3 and 4). In addition, they are 
connected to portions of the Verde River believed to be occupied by 
spikedace.
    Granite Creek occurs predominantly on lands managed by the AGFD in 
their Upper Verde Wildlife Area. The primary emphasis in this area is 
on management of riparian habitat and maintenance of native fish 
diversity. The parcel is 100 hectares (ha) (249 acres (ac)). It is 
surrounded by private lands on which a variety of actions, including 
livestock

[[Page 66509]]

grazing, may occur. The essential features in this unit may require 
special management considerations or protections due to competition 
with or predation by nonnative aquatic species present in both the 
Verde River and Granite Creek, sand and gravel operations, severe 
drought (University of Nebraska-Lincoln 2010) and other water demands, 
and potentially livestock grazing on private lands and associated 
impacts to uplands, riparian vegetation, and the stream.
    This proposed designation includes 54.3 km (33.7 mi) of Oak Creek 
from the confluence with the Verde River upstream to the confluence 
with an unnamed tributary near the Yavapai and Coconino County 
boundary. The lower portions of the creek contain suitable, although 
degraded, habitat. Above the unnamed tributary, the creek becomes 
unsuitable due to urban and suburban development and to increasing 
gradient and substrate size.
    There are no known records of spikedace or loach minnow from Oak 
Creek specifically, but it occurs within the historical range known to 
be occupied by both species. Oak Creek contains suitable habitat for 
all life stages of spikedace and loach minnow (PBF 1); has an 
appropriate food base (PBF 2); consists of perennial streams with no or 
low levels of pollutants (PBFs 3 and 4); and has an appropriate 
hydrologic regime to maintain suitable habitat characteristics (PBF 6). 
Oak Creek is currently being evaluated by a multi-agency team for 
translocation of spikedace and loach minnow. As noted below in the 
Fossil Creek discussion, areas suitable for such actions are rare in 
the desert southwest. As a perennial tributary of the Verde River, and 
a potential translocation site, Oak Creek contains the physical 
features that can provide an important expansion area for spikedace and 
loach minnow recovery. We determined that this area is essential to the 
conservation of both species because it provides suitable areas for a 
possible future barrier construction and species augmentation to 
support both species' recovery.
    Oak Creek occurs on a mix of private and Coconino National Forest 
lands. The essential features in this unit may require special 
management considerations or protections due to competition with and 
predation by nonnative aquatic species; recreation including off-road 
vehicles (ORVs) and associated damage to streams, vegetation and 
streambanks; severe drought (University of Nebraska-Lincoln 2010, p. 
1); and residual effects of livestock grazing and impacts to uplands, 
riparian vegetation, and the stream.
    We are including within the proposed designation 33.5 km (20.8 mi) 
of Beaver and Wet Beaver Creek from the confluence with the Verde River 
upstream to the confluence with Casner Canyon. Beaver Creek and its 
upstream extension in Wet Beaver Creek historically supported spikedace 
(ASU 2002; AGFD 2004) and contains suitable, although degraded, 
habitat. This area is not within the geographic area occupied at 
listing, but it is within the historical range known to be occupied by 
the species. There is one historical record for loach minnow from 
Beaver Creek but none from Wet Beaver Creek. There is one historical 
record for loach minnow on the mainstem Verde River approximately 7.2 
km (4.5 mi) above the confluence with Beaver and Wet Beaver Creek (ASU 
2002; AGFD 2004). Beaver and Wet Beaver Creek currently contain 
suitable habitat for all life stages of spikedace and loach minnow (PBF 
1); have appropriate food bases (PBF 2); consist of perennial streams 
with no or low levels of pollutants (PBFs 3 and 4); and have 
appropriate hydrologic regimes to maintain suitable habitat 
characteristics (PBF 6). As noted under Granite and Oak creeks, habitat 
within this portion of the species' ranges is limited to the Verde 
River Unit, including the Verde and a few of its perennial tributaries 
like Beaver and Wet Beaver Creek. Inclusion of Beaver and Wet Beaver 
Creek expands the overall unit size, adding to available habitat in 
this portion of the species' historical range, as well as expands 
recovery potential for the species in this portion of their historical 
ranges. This area is therefore essential to the conservation of both 
species.
    Beaver and Wet Beaver Creek occur on a mix of private, National 
Park, and Coconino National Forest lands. The essential features in 
this unit may require special management considerations or protection 
due to residual impacts associated with past livestock grazing and 
impacts to uplands, riparian vegetation, and the stream; competition 
with and predation by nonnative aquatic species; severe drought 
(University of Nebraska-Lincoln 2010, p. 1); and increasing human 
development within the watershed.
    We are including within this proposal 7.5 km (4.7 mi) of Fossil 
Creek extending from the confluence with the Verde River upstream to 
the confluence with an unnamed tributary. Fossil Creek was not known to 
be occupied by spikedace or loach minnow at listing. Although 
sufficient flows were previously lacking through this area, in 2005, 
following decommissioning of the Childs-Irving Power Plant, formerly 
diverted flows were returned to Fossil Creek (Robinson 2009b, p. 3). 
Spikedace and loach minnow were translocated into this important 
recovery stream in 2007 (Carter 2007a, p. 1), and additional fish were 
added in 2008 (Carter 2008a, pp. 1-2).
    Fossil Creek contains suitable habitat for all life stages of 
spikedace and loach minnow (PBF 1); has an appropriate food base (PBF 
2); consists of perennial streams with no or low levels of pollutants 
(PBFs 3 and 4); and has an appropriate hydrologic regime to maintain 
suitable habitat characteristics (PBF 6). With the severe reductions in 
the species' overall distribution, and an already initiated 
translocation effort, Fossil Creek is essential to the recovery of 
spikedace and loach minnow as it supports one of the few remaining 
populations for both species. The translocation of spikedace and loach 
minnow into Fossil Creek is part of a larger conservation planning 
effort to restore a native fishery to the creek.
    Fossil Creek occurs primarily on Federal lands, forming the 
boundary between the Coconino and Tonto National Forests. The essential 
features in this unit may require special management considerations or 
protection due to residual effects of past livestock grazing and 
impacts to uplands, riparian vegetation, and the stream; severe drought 
(University of Nebraska-Lincoln 2010, p. 1); and recreation.
    Spikedace only. We are including within this unit 171.8 km (106.7 
mi) of the Verde River from Sullivan Lake downstream to the confluence 
with Fossil Creek. The Verde River mainstem is within the geographic 
area occupied at the time of listing (ASU 2002; M. Brouder, pers. comm. 
2002; AGFD 2004; C. Crowder, AGFD, pers. comm. 2009). Survey efforts 
are not continuous or consistent, and the current status of the 
population in this area is uncertain. Spikedace can be difficult to 
detect in monitoring efforts due to their small size, small population 
sizes, and yearly fluctuations in populations. Populations have been 
known to appear and disappear over time, which makes specific 
determinations on status and exact locations of populations difficult 
to determine. For example, spikedace were not detected in surveys 
conducted in 1950, or again in the 1970s or early 1980s in Eagle Creek, 
but were subsequently detected in 1985 and 1987 (Marsh et al . 1990, 
pp. 107-108). However, given the abundance of nonnative fishes, it is 
likely that any

[[Page 66510]]

remaining spikedace are very rare and only in the uppermost reaches of 
the Verde River.
    While current occupancy remains uncertain, the Verde River is 
essential to the conservation of the species. It currently contains 
suitable habitat for all life stages of spikedace (PBF 1); has an 
appropriate food base (PBF 2); consists of perennial streams with no or 
low levels of pollutants (PBFs 3 and 4); and has an appropriate 
hydrologic regime to maintain suitable habitat characteristics (PBF 6). 
The Verde River is the only occupied stream system in this geographic 
portion of the species' historical range, and represents one of four 
units in this proposed designation in which spikedace are most likely 
to be found. Protection of the species in this portion of the 
historical range will contribute to the long-term conservation of the 
species. Finally, spikedace in the Verde River are genetically (Tibbets 
1993, pp. 25-27, 34) and morphologically (Anderson and Hendrickson 
1994, pp. 148, 154) distinct from all other spikedace populations.
    The essential features in this unit may require special management 
considerations and protections due to water diversions; existing and 
proposed groundwater pumping potentially resulting in drying of 
habitat; residual effects of past livestock grazing and impacts to 
uplands, riparian vegetation, and the stream channel; human development 
of surrounding areas; increased recreation including off-road vehicle 
use; severe drought (University of Nebraska-Lincoln 2010, p. 1); and 
competition with or predation by nonnative aquatic species.
    We are including 10.9 km (6.8 mi) of West Clear Creek from the 
confluence with the Verde River upstream to the confluence with Black 
Mountain Canyon. Gradient and channel morphology changes above Black 
Mountain Canyon make the upstream area unsuitable for spikedace. The 
lower portion of West Clear Creek was known to be occupied by spikedace 
at listing (ASU 2002; AGFD 2004) and contains suitable habitat for all 
life stages of spikedace (PBF 1); has an appropriate food base (PBF 2); 
and consists of perennial streams with no or low levels of pollutants 
(PBFs 3 and 4). West Clear Creek is under consideration as a 
translocation site for spikedace by a multi-agency team. The presence 
of PBFs, its past occupancy, and its consideration for translocation of 
spikedace indicate the suitability of this area, which will serve as an 
important expansion area for spikedace recovery.
    West Clear Creek is on private and Coconino National Forest lands. 
West Clear Creek runs through private land for several miles in the 
vicinity of the Town of Camp Verde. The essential features in this unit 
may require special management considerations or protection due to 
impacts associated with rural residential uses adjacent to the channel; 
agriculture; residual effects of past livestock grazing and impacts to 
uplands, riparian vegetation, and the stream; severe drought 
(University of Nebraska-Lincoln 2010, p. 1); and competition with and 
predation by nonnative aquatic species.
    Loach minnow only. We include within this unit 119.7 km (74.4 mi) 
of the Verde River from Sullivan Lake downstream to the confluence with 
Wet Beaver Creek. This mileage partially overlaps mileage proposed for 
designation as critical habitat for spikedace, which extends further 
downstream on the Verde River than this segment for loach minnow. This 
area is within the geographic area occupied by loach minnow at the time 
of listing. Surveys completed during the 1930s detected both species 
near Wet Beaver Creek. Spikedace and loach minnow were known to co-
occur throughout much of their historical ranges. While spikedace were 
detected as far south as West Clear Creek, loach minnow were not. 
Subsequent surveys in more recent years have failed to detect either 
species. While incomplete, there are no known records of loach minnow 
from any point lower on the Verde River than Wet Beaver Creek.
    The Verde River contains the suitable physical habitat features for 
all life stages of loach minnow (PBF 1); has an appropriate food base 
(PBF 2); consists of perennial streams with no or low levels of 
pollutants (PBFs 3 and 4); and has an appropriate hydrologic regime to 
maintain suitable habitat characteristics (PBF 6). The Verde River is 
located in the far northwestern portion of the species' range, and is 
the only river system in that geographic portion of the species' range. 
The suitability and location make the Verde River essential to the 
conservation of the loach minnow.
    Land ownership and actions requiring special management 
considerations and protections for loach minnow are as summarized for 
spikedace in the above description of the Verde River for spikedace.

Unit 2: Salt River Subbasin

Spikedace and Loach Minnow
    We are not proposing to designate any portion of the mainstem Salt 
River as critical habitat for spikedace at this time. Those portions 
below Theodore Roosevelt Reservoir have been altered by numerous dams 
and reservoirs, permanently limiting the natural flow regime and 
resulting in regulated flows. Those portions of the Salt River above 
the Reservoir support three historical records of spikedace near the 
confluence with Cibecue Creek. However, the Salt River, as well as the 
lower portions of Cibecue Creek, are canyon bound. While spikedace may 
occur in or travel through canyon areas, long stretches of canyon-bound 
river typically do not support the wider, shallower streams in which 
spikedace occur. Canyons are typically associated with a bedrock 
substrate, rather than the sand, gravel, or cobble over which spikedace 
are typically found. Where the river does have wider areas, it is 
currently dominated by nonnative fish species. Due to its limited 
available habitat, limited habitat suitability, and permanent 
alteration for reservoirs, we are not able to conclude that this area 
is essential to the conservation of the spikedace at this time.
    In previous designations, we have included portions of Tonto Creek, 
Rye Creek, and Greenback Creek as critical habitat for loach minnow. 
These areas have no historical records for loach minnow. The limited 
mileage and habitat features make these areas less important to the 
overall conservation of loach minnow, and our current assessment is 
that the suitability for loach minnow in these streams is limited. We 
believe the habitat in the White and Black River systems is more 
suitable for loach minnow, and inclusion of these areas as critical 
habitat is sufficient to meet the preliminary recovery goals for the 
Salt River basin. We continue to propose these areas for spikedace 
critical habitat, as there are no records for spikedace from either the 
White or Black river systems, so that Tonto Creek and its tributaries 
represent the only occupied habitat within the Salt River subbasin for 
that species.
    Spikedace. Unit 2 consists of 98.78 km (61.3 mi) of river on Tonto 
Creek and its tributaries Greenback, Rye, and Spring creeks, as well as 
Rock Creek, a tributary to Spring Creek, in Gila County, Arizona. The 
Salt River subbasin is a significant portion of spikedace historical 
range but currently has no known extant populations of spikedace. Large 
areas of the subbasin are unsuitable, either because of topography or 
because of reservoirs and other stream-channel alterations. Historical 
records for spikedace are from the Salt River near the confluence with

[[Page 66511]]

Cibecue Creek; the Salt River immediately below what is now Theodore 
Roosevelt Reservoir; and the Salt River in what is now Saguaro Lake 
(ASU 2002; AGFD 2004). With the exception of the record near Cibecue, 
existing locations have been substantially modified by the development 
of a series of dams and reservoirs. Streamflow between these reservoirs 
is regulated, removing the natural flow regime previously associated 
with the Salt River.
    We are including within this proposal 47.8 km (29.7 mi) of Tonto 
Creek from the confluence with Greenback Creek upstream to the 
confluence with Houston Creek. Tonto Creek below Greenback Creek is 
influenced by Theodore Roosevelt Reservoir, resulting in unsuitable 
habitat below Greenback Creek. Those portions of Tonto Creek above the 
confluence with Houston Creek are of a gradient and substrate that are 
not suitable to spikedace. Tonto Creek was known to be occupied at 
listing (Abarca and Weedman 1993, p. 1; ASU 2002; AGFD 2004) but is not 
currently occupied. Tonto Creek supports perennial reaches that contain 
suitable habitat for all life stages of spikedace (PBF 1); has an 
appropriate food base (PBF 2); and consists of perennial flow with no 
or low levels of pollutants (PBFs 3 and 4).
    The Salt River tributaries included in this proposal, Tonto Creek, 
Greenback Creek, Rye Creek, Spring Creek, and Rock Creek, occur almost 
entirely on the Tonto National Forest, with a few parcels of private 
land interspersed among Forest lands. The essential features in this 
unit may require special management considerations or protection due to 
residual impacts from past livestock grazing and impacts to uplands, 
riparian vegetation, and the stream; competition with and predation by 
nonnative aquatic species; moderate drought (University of Nebraska-
Lincoln 2010, p. 1); water diversions that diminish flows in the active 
channel; and road maintenance that results in repeated impacts to the 
channel.
    We are including within the proposed designation 15.1 km (9.4 mi) 
of Greenback Creek beginning at the confluence with Tonto Creek and 
continuing upstream to the confluence with Lime Springs. Portions of 
Greenback Creek are intermittent, but may connect Greenback Creek to 
Tonto Creek during seasonal flows. There are no known records of 
spikedace from Greenback Creek, but it is a tributary to Tonto Creek, 
which was known to be occupied at listing. Greenback Creek contains 
suitable habitat for all life stages of spikedace (PBF 1); has an 
appropriate food base (PBF 2); and consists of perennial streams with 
no or low levels of pollutants (PBFs 3 and 4). As noted above, the Salt 
River subbasin is a significant portion of spikedace historical range, 
but there are limited areas of suitable habitat. The suitable habitat, 
its connection with Tonto Creek, and fact that it occurs almost 
entirely on Federal lands make Greenback Creek an important expansion 
area for spikedace recovery, and it is therefore essential to the 
conservation of the species.
    We are including within this proposal 2.8 km (1.8 mi) of Rye Creek 
from the confluence with Tonto Creek upstream to the confluence with 
Brady Canyon. There are no known records of spikedace from Rye Creek, 
but it occurs within the historical range known to be occupied by the 
species. The entire portion of the proposed designation is perennial. 
Rye Creek contains suitable habitat for all life stages of spikedace 
(PBF 1); has an appropriate food base (PBF 2); and consists of 
perennial streams with no or low levels of pollutants (PBFs 3 and 4). 
As with Greenback Creek, Rye Creek serves as connected perennial stream 
habitat that expands the available habitat associated with Tonto Creek 
and the Salt River subbasin, and it is therefore essential to the 
conservation of the species.
    We are including within this proposal 27.2 km (16.9 mi) of Spring 
Creek from the confluence with Tonto Creek upstream to its confluence 
with Sevenmile Canyon. There are no known records of spikedace from 
Spring Creek, but it occurs within the historical range known to be 
occupied by the species. The entire portion of the proposed designation 
is perennial. Spring Creek contains suitable habitat for all life 
stages of spikedace (PBF 1); has an appropriate food base (PBF 2); and 
consists of perennial streams with no or low levels of pollutants (PBFs 
3 and 4). Spring Creek serves as connected perennial stream habitat 
that expands the available habitat associated with Tonto Creek and the 
Salt River subbasin, and it is therefore essential to the conservation 
of the species. In addition, for both Rock and Spring creeks, 
conservation efforts for spikedace are underway. The feasibility of 
constructing a barrier and translocating spikedace to Spring Creek, a 
tributary to Tonto Creek, has been initiated with draft NEPA documents 
under development.
    We are including within this proposal 5.8 km (3.6 mi) of Rock Creek 
from its confluence with Spring Creek upstream to its confluence with 
Buzzard Roost Canyon. There are no known records of spikedace from Rock 
Creek, but it occurs within the historical range known to be occupied 
by the species. Rock Creek contains suitable habitat for all life 
stages of spikedace (PBF 1); has an appropriate food base (PBF 2); and 
consists of perennial streams with no or low levels of pollutants (PBFs 
3 and 4). Rock Creek will further expand the available habitat in the 
Salt River Subbasin. As noted above under Spring Creek, conservation 
planning efforts are underway that will likely lead to a translocation 
of spikedace into Rock Creek. The suitable habitat, perennial flows, 
and location within the Salt River subbasin make Rock Creek essential 
to the conservation of the spikedace.
    Loach minnow. Unit 2 consists of 51.9 km (32.2 mi) of the White 
River and its tributary East Fork White River; and East Fork Black 
River, North Fork East Fork Black River, and Coyote and Boneyard creeks 
in Gila, Navajo, and Apache Counties, Arizona. Portions of this unit 
are known to have been occupied at listing, while others have 
historical records. The Salt River subbasin is a significant portion of 
loach minnow historical range, and the Salt River mainstem was known at 
listing to have historical records near the confluence with Cibecue 
Creek. The Black and White Rivers, which join to form the Salt River, 
are also known to have been occupied at listing. Within this subbasin, 
loach minnow have been extirpated from all but a small portion of the 
Black and White Rivers.
    We are including within this proposal 29.0 km (18.0 mi) of the 
White River from the confluence with the Black River upstream to the 
confluence with the North and East Forks of the White River. Loach 
minnow were known at the time of listing to have occurred in this 
portion of the White River (M. Douglas, ASU, pers. comm. 1988; ASU 
2002). The White River contains suitable habitat for all life stages of 
loach minnow (PBF 1); has an appropriate food base (PBF 2); consists of 
perennial streams with no or low levels of pollutants (PBFs 3 and 4); 
and has an appropriate hydrologic regime to maintain suitable habitat 
characteristics (PBF 6). Current occupancy of this area is unknown due 
to the proprietary nature of Tribal survey information. The length of 
perennial flows with suitable habitat parameters, historical occupancy, 
and potential current occupancy make this area essential to the 
conservation of the loach minnow.
    The proposed designation on the White River is entirely within 
lands owned by the White Mountain Apache Tribe. This area will be 
considered for exclusion from the final critical habitat

[[Page 66512]]

designation under section 4(b)(2) of the Act (see ``Application of 
Section 4(b)(2) of the Act'' section below for additional information).
    The essential features in this unit may require special management 
considerations or protection due to residual effects of past livestock 
grazing and impacts to uplands, riparian vegetation, and the stream; 
competition with and predation by nonnative aquatic species; and 
moderate drought (University of Nebraska-Lincoln 2010, p. 1).
    We are including within this proposal 17.2 km (10.7 mi) of the East 
Fork White River from the confluence with North Fork White River 
upstream to the confluence with Bones Canyon. Loach minnow were known 
at the time of listing to have occurred in these portions of the East 
Fork White River (Leon 1989; pp. 1-2; ASU 2002; Service 2006, pp. 2-3). 
These areas contains suitable habitat for all life stages of loach 
minnow (PBF 1); have an appropriate food base (PBF 2); consist of 
perennial streams with no or low levels of pollutants (PBFs 3 and 4); 
and have an appropriate hydrologic regime to maintain suitable habitat 
characteristics (PBF 6). As perennial streams within the Salt River 
subbasin, these streams are considered essential to the recovery and 
survival of loach minnow.
    The proposed designation on East Fork White River is entirely 
within lands owned by the White Mountain Apache Tribe. This area will 
be considered for exclusion from the final critical habitat designation 
under section 4(b)(2) of the Act (see ``Application of Section 4(b)(2) 
of the Act'' section below for additional information).
    The essential features in this unit may require special management 
considerations or protection due to residual effects of past livestock 
grazing and impacts to uplands, riparian vegetation, and the stream; 
competition with and predation by nonnative aquatic species; and 
moderate drought (University of Nebraska-Lincoln 2010, p. 1).
    The North Fork White River was not specifically known to be 
occupied at the time of listing, but has been known to be occupied at 
times since listing. However, the North Fork White River is not thought 
to be able to support a breeding population of loach minnow, but 
rather, the collections of loach minnow in the North Fork of the White 
River are thought to be attributable to upstream migration from the 
breeding population found in the East Fork White River. It is suspected 
that high temperatures may be a limiting factor in the establishment of 
viable loach minnow populations in the North Fork White River (Raleigh 
Consultants 1995). Further, this reach is comprised of swift, deep runs 
which are not characteristic of the preferred shallow riffle habitat of 
the loach minnow (Raleigh Consultants 1996). Due to these factors, we 
cannot conclude that the North Fork White River supports adequate PBFs 
to support essential life history functions of loach minnow and we are 
not including this area within the proposed critical habitat 
designation.
    The Salt River Subbasin also includes a total of 32.0 km (20 mi) of 
the East Fork Black River and its tributary Coyote Creek, and the North 
Fork East Fork Black River and its tributary Boneyard Creek. We are 
including within this proposal 19.1 km (11.9 mi) of the East Fork Black 
River extending from the confluence with the West Fork Black River 
upstream to the confluence with Boneyard Creek. East Fork Black River 
contains suitable habitat for all life stages of loach minnow (PBF 1); 
has an appropriate food base (PBF 2); consists of perennial streams 
with no or low levels of pollutants (PBFs 3 and 4); and has an 
appropriate hydrologic regime to maintain suitable habitat 
characteristics (PBF 6). The presence of multiple PBFs, and the 
presence of a distinct genetic population in the adjoining North Fork 
East Fork River, makes this area essential to the conservation of loach 
minnow.
    Those portions of the East Fork Black River, the portions of the 
North Fork East Fork Black River, and the portions of Boneyard and 
Coyote Creek included within this proposal are entirely on Apache-
Sitgreaves National Forests lands. The essential features in this unit 
may require special management considerations or protection due to 
residual effects of past livestock grazing and impacts to uplands, 
riparian vegetation, and the stream; and competition with and predation 
by nonnative aquatic species. Native trout species are regularly 
stocked into the Black River and may also increase competition for 
resources and predation by trout. Wildfire has occurred in this area in 
the past, and there may be minimal increases in sediment carried into 
the stream from burned areas in the uplands.
    We are including within this proposal 7.1 km (4.4 mi) of the North 
Fork East Fork Black River extending from the confluence with East Fork 
Black River upstream to the confluence with an unnamed tributary. Above 
this tributary, the river has finer substrate and lacks riffle habitat, 
making it unsuitable for loach minnow. The North Fork East Fork Black 
River is currently occupied (ASU 2002; S. Gurtin, AGFD, pers. comm. 
2004; Robinson et al. 2009b, p. 1), and is presumed to have been 
occupied at listing. The North Fork East Fork Black River contains 
suitable habitat for all life stages of loach minnow (PBF 1); has an 
appropriate food base (PBF 2); consists of perennial streams with no or 
low levels of pollutants (PBFs 3 and 4); and has an appropriate 
hydrologic regime to maintain suitable habitat characteristics (PBF 6). 
As with the East Fork Black River, the presence of multiple PBFs, its 
occupied status, and the presence of a distinct genetic population make 
this area essential to the conservation of loach minnow.
    We are including within the proposal 2.3 km (1.4 mi) of Boneyard 
Creek extending from the confluence with the East Fork Black River 
upstream to the confluence with an unnamed tributary. Occupancy of this 
area is uncertain, but it is connected to the North Fork East Fork 
Black River which is occupied by loach minnow (ASU 2002; S. Gurtin, 
AGFD, pers. comm. 2004; Robinson et al. 2009b, p. 1). It contains 
suitable habitat for all life stages of loach minnow (PBF 1); has an 
appropriate food base (PBF 2); consists of perennial streams with no or 
low levels of pollutants (PBFs 3 and 4); and has an appropriate 
hydrologic regime to maintain suitable habitat characteristics (PBF 6). 
As with the East Fork Black and North Fork East Fork Black rivers, the 
presence of multiple PBFs, and the presence of a distinct genetic 
population in the adjacent river, makes this area essential to the 
conservation of loach minnow.
    We are including within this proposal 3.4 km (2.1 mi) of Coyote 
Creek, extending from the confluence with East Fork Black River 
upstream to the confluence with an unnamed tributary. This area is 
considered occupied and is connected to the North Fork East Fork Black 
River, which is occupied by loach minnow (M. Lopez, AGFD, pers. comm. 
2000; ASU 2002; S. Gurtin, AGFD, pers. comm. 2004, Robinson et al. 
2009b, p. 1). The portions of Coyote Creek proposed for inclusion in 
this proposed designation contain suitable habitat for all life stages 
of loach minnow (PBF 1); have an appropriate food base (PBF 2); and 
consist of perennial streams with no or low levels of pollutants (PBFs 
3 and 4). As with the East Fork Black and North Fork East Fork Black 
rivers and Boneyard Creek, the presence of multiple PBFs, its occupied 
status, and the presence of a distinct genetic population make this 
area essential to the conservation of loach minnow.

[[Page 66513]]

Unit 3: San Pedro Subbasin

    Spikedace and loach minnow. Unit 3 consists of 159.7 km (99.3 mi) 
of habitat on the upper San Pedro River, Aravaipa Creek and its 
tributaries Deer and Turkey creeks, Redfield and Hot Springs canyons, 
as well as Bass Canyon, tributary to Hot Springs Canyon, in Cochise, 
Pima, Pinal, and Graham Counties, Arizona. The San Pedro subbasin 
contains streams that are known to have been occupied by both species 
at listing, some of which are currently occupied, as well as streams 
with translocated populations of spikedace and loach minnow.
    We are including within this proposal 60.0 km (37.2 mi) on the 
upper San Pedro River from the international border with Mexico 
downstream to the confluence with the Babocomari River. North of this 
confluence, the San Pedro was perennial, but does not currently support 
adequate flows for spikedace and loach minnow. Portions of the San 
Pedro River included within this proposed designation were known to be 
occupied by both species at listing. Multiple occurrence records of 
each species indicate the suitability of this area (ASU 2002; AGFD 
2004). This portion of the San Pedro River contains suitable habitat 
for all life stages of loach minnow (PBF 1); has an appropriate food 
base (PBF 2); and consists of perennial streams with no or low levels 
of pollutants (PBFs 3 and 4). The BLM has identified this area as 
having high restoration potential for spikedace and loach minnow. This 
portion of the San Pedro represents the southernmost extension of the 
two species' historical range. Suitable habitat within this geographic 
area is limited. Because of the presence of more than one PBF 
(including perennial flows), the abundance of historical records, and 
its importance to the overall range of the species, this area is 
considered essential to the conservation of both species.
    The majority of this area is on lands managed by the BLM, with 
small portions of private and State lands. The essential features in 
this unit may require special management considerations or protection 
due to residual effects of past livestock grazing and impacts to 
uplands, riparian vegetation, and the stream; competition with and 
predation by nonnative aquatic species; water developments; severe 
drought (University of Nebraska-Lincoln 2010, p. 1); and increasing 
human development within the watershed.
    We are including within this proposal 44.9 km (27.91 mi) of 
Aravaipa Creek from the confluence with the San Pedro River upstream to 
the confluence with Stowe Gulch. Stowe Gulch is the upstream limit of 
sufficient perennial flows to support spikedace and loach minnow; no 
records of either species are known from above this point. Aravaipa 
Creek currently supports one of the largest remaining populations of 
spikedace and loach minnow, and has been monitored since 1943 (ASU 
2002; Stefferud and Reinthal 2005, pp. 15-21; AGFD 2004; P. Reinthal, 
University of Arizona pers. comm. 2008; Reinthal 2009, pp. 1-2). 
Aravaipa Creek is unique in that it supports an intact native fish 
fauna comprised of seven species (Stefferud and Reinthal 2005, p. 11). 
It contains suitable habitat for all life stages of spikedace (PBF 1); 
has an appropriate food base (PBF 2); consists of perennial flows (PBF 
3); has no nonnative aquatic species, or levels of nonnative aquatic 
species that are sufficiently low to allow persistence of spikedace 
(PBF 5); and has an appropriate hydrologic regime to maintain suitable 
habitat characteristics (PBF 6). The presence of all PBFs, and long-
term presence and current occupancy by spikedace, makes this area 
essential to the conservation of the species.
    Land ownership at Aravaipa Creek is predominantly BLM, with large 
parcels of private and State land on either end of the river. The 
essential features in this unit may require special management 
considerations or protection due to contaminants issues with lead, 
arsenic, and cadmium; surface and groundwater removal; limited 
recreation; severe drought (University of Nebraska-Lincoln 2010, p. 1); 
and channelization in upstream portions (Stefferud and Reinthal 2005, 
pp. 36-38).
    We are including within this proposal 3.7 km (2.3 mi) of Deer Creek 
from the confluence with Aravaipa Creek upstream to the boundary of the 
Aravaipa Wilderness. Above this point, habitat is no longer suitable 
for spikedace or loach minnow. We are also including 4.3 km (2.7 mi) of 
Turkey Creek from the confluence with Aravaipa Creek upstream to the 
confluence with Oak Grove Canyon. Above this point, flows are not 
suitable for spikedace or loach minnow. Loach minnow are known to have 
occupied Deer and Turkey creeks at listing, while spikedace are not. 
Each of these tributary streams contains suitable habitat for all life 
stages of spikedace and loach minnow (PBF 1); has appropriate food 
bases (PBF 2); consists of perennial streams with no or low levels of 
pollutants (PBFs 3 and 4); and has an appropriate hydrologic regime to 
maintain suitable habitat characteristics (PBF 6).
    Both Deer and Turkey creeks occur on lands managed by the BLM. The 
essential features in these two streams may require special management 
due to surface and groundwater removal; limited recreation; severe 
drought (University of Nebraska-Lincoln 2010, p. 1); occasional issues 
with nonnative aquatic species; and proposed utilities projects, such 
as the SunZia Southwest Transmission Project, which is currently in the 
study phase (Service 2010b, pp. 1-7). Deer and Turkey Creek are 
tributaries to Aravaipa Creek which is currently occupied by spikedace 
and so serve as an extension of the occupied habitat, and are therefore 
essential to the conservation of the species.
    We are including within this proposal 19.0 km (11.8 mi) of stream 
in Hot Springs Canyon from the confluence with the San Pedro River 
upstream to the confluence with Bass Canyon. (The stream in Hot Springs 
Canyon is not named and is known only as Hot Springs Canyon.) There are 
no known records of spikedace or loach minnow from Hot Springs Canyon, 
but it is within the geographical range known to be occupied by both 
species. Following coordination by a multi-agency team, spikedace and 
loach minnow were translocated into Hot Springs Canyon in 2007, with 
augmentations in 2008 and 2009 (Robinson 2008a, pp. 1, 15-16; Robinson 
et al. 2010, pp. 4-5). Hot Springs Canyon contains suitable habitat for 
all life stages of spikedace and loach minnow (PBF 1); has an 
appropriate food base (PBF 2); consists of perennial streams with no or 
low levels of pollutants (PBFs 3 and 4); has no nonnative aquatic 
species, or levels of nonnative aquatic species that are sufficiently 
low to allow persistence of spikedace and loach minnow (PBF 5); and has 
an appropriate hydrologic regime to maintain suitable habitat 
characteristics (PBF 6). The current occupancy by spikedace and loach 
minnow and presence of all PBFs, which extend the habitat available in 
this unit, make this area essential to the conservation of the species.
    Hot Springs Canyon occurs on a mix of State, private, and BLM 
lands. The essential features in these two streams may require special 
management due to low flows or dewatering associated with severe 
drought (University of Nebraska-Lincoln 2010, p. 1) and climate change, 
and proposed utilities projects (as noted above under Aravaipa Creek 
(Service 2010, pp. 1-7)).
    We are including within this proposal 22.5 km (14.0 mi) of stream 
in Redfield

[[Page 66514]]

Canyon from the confluence with the San Pedro River upstream to the 
confluence with Sycamore Canyon. (The stream in Redfield Canyon is not 
named and is known only as Redfield Canyon.) Above Sycamore Canyon, 
perennial water becomes very scarce, and the habitat becomes steeper, 
and more canyon-confined. Although there are no known records of 
spikedace or loach minnow from Redfield Canyon, it is within the 
geographical range known to be occupied by both species. Following 
coordination by a multi-agency team, spikedace and loach minnow were 
translocated into Redfield Canyon in 2007, with augmentations in 2008 
(Robinson 2008b, pp. 1, 15-16; Robinson et al. 2010, pp. 4-5). Redfield 
Canyon contains suitable habitat for all life stages of spikedace and 
loach minnow (PBF 1); has an appropriate food base (PBF 2); consists of 
perennial streams with no or low levels of pollutants (PBFs 3 and 4); 
has no nonnative aquatic species, or levels of nonnative aquatic 
species that are sufficiently low to allow persistence of spikedace and 
loach minnow (PBF 5); and has an appropriate hydrologic regime to 
maintain suitable habitat characteristics (PBF 6). Redfield Canyon was 
specifically identified within the species' Recovery Plan as an area 
with potential for spikedace (Service 1991a, p. 21; Service 1991b, p. 
20). The current occupancy by spikedace and loach minnow and presence 
of all PBFs, which extends the available habitat in this unit, make 
this area essential to the conservation of the species.
    Redfield Canyon occurs on primarily State lands, with small areas 
of private and Federal (BLM) lands. The essential features in Redfield 
Canyon may require special management due to occasional issues with 
nonnative aquatic species, low flows or dewatering associated with 
severe drought (University of Nebraska-Lincoln 2010, p. 1) and climate 
change, and proposed utilities projects (such as the SunZia Southwest 
Transmission Project as noted above under Aravaipa Creek).
    We are including within this proposal 5.5 km (3.4 mi) of stream in 
Bass Canyon from the confluence with Hot Springs Canyon upstream to the 
confluence with Pine Canyon. (The stream in Bass Canyon is not named 
and is known only as Hot Springs Canyon.) There are no known records of 
spikedace or loach minnow from Bass Canyon, but it is within the 
geographical range known to be occupied by both species, and spikedace 
and loach minnow have been translocated into Hot Springs Canyon, to 
which Bass Canyon is connected and is a tributary stream (see 
discussion above under Hot Springs Canyon). Bass Canyon contains 
suitable habitat for all life stages of spikedace and loach minnow (PBF 
1); has an appropriate food base (PBF 2); consists of perennial streams 
with no or low levels of pollutants (PBFs 3 and 4); and has no 
nonnative aquatic species, or levels of nonnative aquatic species that 
are sufficiently low to allow persistence of spikedace and loach minnow 
(PBF 5). Bass Canyon serves as an extension to Hot Springs Canyon and 
supports multiple PBFs. We therefore consider it to be essential to the 
conservation of both species.
    The essential features in these two streams may require special 
management due to low flows or dewatering associated with severe 
drought (University of Nebraska-Lincoln 2010, p. 1) and climate change, 
and proposed utilities projects (such as the SunZia Southwest 
Transmission Project as noted above under Aravaipa Creek).
    Cooperative conservation efforts for spikedace and loach minnow are 
ongoing in Hot Springs Canyon, Bass Canyon, and Redfield Canyon. To 
date, those activities have resulted in the translocation, 
augmentation, and monitoring of five native fishes, including spikedace 
and loach minnow. A multi-agency committee continues to work 
cooperatively on this multi-stream, multi-species conservation effort.

Unit 4: Bonita Creek Subbasin

Spikedace and Loach Minnow
    We are including within this proposal 23.8 km (14.8 mi) of Bonita 
Creek from the confluence with the Gila River upstream to the 
confluence with Martinez Wash in Graham County, Arizona. The Bonita 
Creek subbasin is not known to have been occupied at listing but is 
within the geographical range known to have been occupied by both 
species. In 2008, spikedace and loach minnow were translocated into the 
lower portions of Bonita Creek (T. Robinson, AGFD, pers. comm. 2008c), 
with a small population of spikedace placed above the City of Safford's 
infiltration gallery, but below the southern boundary of the San Carlos 
Indian Reservation, in 2009. As noted above for Fossil Creek and Hot 
Springs Canyon and Redfield Canyon, there are limited opportunities for 
translocating or reintroducing populations of spikedace, and the 
reduction in the species' distribution necessitates that additional 
populations be established to recover the species. Bonita Creek is 
considered essential to the survival and recovery of spikedace and 
loach minnow because it contains suitable habitat for all life stages 
of spikedace (PBF 1); has an appropriate food base (PBF 2); and 
consists of perennial flow with no or low levels of pollutants (PBFs 3 
and 4). It also allows for the expansion of the geographic distribution 
of the species' ranges.
    Land ownership at Bonita Creek is almost entirely Federal under the 
BLM, with a few small private parcels. The proposed designation ends at 
the San Carlos Indian Reservation boundary. Critical habitat within 
this subbasin requires special management for nonnative aquatic 
species, some recreation, residual effects of past livestock grazing, 
moderate drought (University of Nebraska-Lincoln 2010, p. 1), and water 
diversion. Following rehabilitation of the stream, Bonita Creek will 
have no to at most low levels of nonnative aquatic species (PBF 5).
    Cooperative conservation efforts for spikedace and loach minnow are 
ongoing in Bonita Creek. To date, those activities have resulted in the 
removal of nonnative fish species and translocation of spikedace, loach 
minnow, Gila topminnow, and desert pupfish into Bonita Creek. A 
Memorandum of Understanding was signed with the City of Safford 
regarding water management for Bonita Creek as part of this effort.

Unit 5: Eagle Creek Subbasin

    Spikedace and loach minnow. We are including within this proposal 
75.5 km (46.9 mi) of Eagle Creek from the Freeport McMoRan diversion 
dam upstream to the confluence with East Eagle Creek in Greenlee and 
Graham Counties, Arizona. Freeport McMoRan is a copper mining company 
formerly known as Phelps Dodge. Eagle Creek was known to be occupied at 
the time of listing by both spikedace and loach minnow. Loach minnow 
and spikedace are both considered present, but likely in small numbers, 
as suitable habitat is present (Marsh 1996, p. 2; ASU 2002; Bahm and 
Robinson 2009a, p. 1).
    Eagle Creek contains suitable habitat for all life stages of 
spikedace and loach minnow (PBF 1); has an appropriate food base (PBF 
2); consists of perennial flows with no or low levels of pollutants 
(PBFs 3 and 4); and has an appropriate hydrologic regime to maintain 
suitable habitat characteristics (PBF 6) above the barrier, which 
serves as the endpoint of this unit.
    Eagle Creek occurs primarily on San Carlos Apache Tribal and 
Apache-Sitgreaves National Forests' lands, along with small parcels of 
State, private, and BLM lands. The essential features in

[[Page 66515]]

this stream may require special management considerations or protection 
due to competition with and predation by nonnative aquatic species; 
residual effects of past livestock grazing and impacts to uplands, 
riparian vegetation, and the stream; mining activities in the uplands; 
moderate drought (University of Nebraska-Lincoln 2010, p. 1); and road 
construction and maintenance within and adjacent to the stream channel.
    Those portions of Eagle Creek in Graham County are on the San 
Carlos Apache Reservation. Additionally, portions of Eagle Creek also 
flow through private lands belonging to Freeport McMoRan. These areas 
will be considered for exclusion from the final critical habitat 
designation under section 4(b)(2) of the Act (see ``Application of 
Section 4(b)(2) of the Act'' section below for additional information).

Unit 6: San Francisco River Subbasin

    Spikedace and loach minnow. We are including within this proposal 
181.0 km (112.3 mi) of the San Francisco River extending from the 
confluence with the Gila River in Greenlee County, Arizona upstream to 
the confluence with the Tularosa River in Catron County, New Mexico. 
Above the confluence with the Tularosa River, habitat is no longer 
suitable for spikedace or loach minnow. The San Francisco River, 
downstream of the Tularosa River confluence, was known to be occupied 
by spikedace at listing, and a reintroduction of spikedace occurred in 
2008, above the town of Alma, New Mexico (NMDGF 2009, p. 1). This area 
was also known to be occupied by loach minnow at listing, and is 
currently occupied by loach minnow (NMDGF 2008; Propst et al. 2009, pp. 
5-6). The San Francisco River is perennial throughout this length, and 
contains suitable habitat for all life stages of spikedace (PBF 1); has 
an appropriate food base (PBF 2); consists of perennial flows with no 
or low levels of pollutants (PBFs 3 and 4); and has an appropriate 
hydrologic regime to maintain suitable habitat characteristics (PBF 6). 
The San Francisco River is one of the larger intact streams remaining 
within the species' ranges, with an overall length of approximately 202 
km (125 mi). Because it represents one of the largest remaining rivers 
in the species' historical ranges, was historically occupied, has a 
reintroduced population of spikedace, is currently occupied by loach 
minnow, and supports several of the PBFs for spikedace, this area is 
essential to the conservation of spikedace and loach minnow.
    Land ownership on the San Francisco River includes primarily BLM 
and Apache-Sitgreaves National Forests with small parcels of private 
and State lands in Arizona, and the Gila National Forest with small 
parcels of private lands in New Mexico. The essential features in this 
stream may require special management considerations or protection due 
to livestock grazing and impacts to uplands, riparian vegetation, and 
the stream; moderate drought (University of Nebraska-Lincoln 2010, p. 
1) in those portions in Arizona; competition with and predation by 
nonnative aquatic species; water diversions; road construction and 
maintenance; and channelization.
    We are not including portions of the Tularosa River, Whitewater 
Creek, or Negrito Creek as critical habitat for spikedace in this 
proposal. There are no known records of spikedace from these streams, 
and spikedace have not been known to occur any higher in the San 
Francisco River than Pleasanton (Paroz and Propst 2007, pp. 13-15).
    Loach minnow only: We are proposing 30.0 km (18.6 mi) of the 
Tularosa River from the confluence with the San Francisco River 
upstream to the town of Cruzville, New Mexico. Above Cruzville, habitat 
becomes unsuitable for loach minnow. The Tularosa River is currently 
occupied by loach minnow (Propst et al. 2009, pp. 4-5). The Tularosa 
River is perennial throughout this reach, and contains suitable habitat 
for all life stages of loach minnow (PBF 1); has an appropriate food 
base (PBF 2); consists of perennial flows with no or low levels of 
pollutants (PBFs 3 and 4); and has an appropriate hydrologic regime to 
maintain suitable habitat characteristics (PBF 6). This area is 
considered essential to the conservation of loach minnow because it is 
currently occupied, supports more than one of the PBFs, and is 
connected to occupied habitat on the San Francisco River.
    We are including within this proposal 6.8 km (4.2 mi) of Negrito 
Creek extending from the confluence with the Tularosa River upstream to 
the confluence with Cerco Canyon. Above this point, gradient and 
channel morphology make the creek unsuitable for loach minnow. Negrito 
Creek has been recently occupied by loach minnow, and is within the 
historical range known to be occupied by the species at listing. 
Negrito Creek is perennial through this reach, and contains suitable 
habitat for all life stages of loach minnow (PBF 1); has an appropriate 
food base (PBF 2); consists of perennial flows with no or low levels of 
pollutants (PBFs 3 and 4); and has an appropriate hydrologic regime to 
maintain suitable habitat characteristics (PBF 6). This area is 
considered essential to the conservation of loach minnow because of its 
occupancy history, and because it supports more than one of the PBFs 
and expands suitable habitat for loach minnow in this unit.
    Negrito Creek occurs primarily on the Gila National Forest, with a 
few parcels of private land interspersed with the Forest lands. The 
essential features in this stream may require special management 
considerations or protection due to residual effects of past livestock 
grazing and impacts to uplands, riparian vegetation, and the stream, as 
well as other disturbances in the watershed.
    We are also including within this proposed designation 1.9 km (1.2 
mi) of Whitewater Creek from the confluence with the San Francisco 
River upstream to the confluence with Little Whitewater Creek. Upstream 
of this point, gradient and channel changes make the habitat unsuitable 
for loach minnow. Whitewater Creek was known to be occupied by loach 
minnow at the time of listing and has perennial flows. It serves as an 
extension of habitat on the San Francisco River. Whitewater Creek 
contains suitable habitat for all life stages of loach minnow (PBF 1); 
has an appropriate food base (PBF 2); consists of perennial flows with 
no or low levels of pollutants (PBFs 3 and 4); and has an appropriate 
hydrologic regime to maintain suitable habitat characteristics (PBF 6).
    Whitewater Creek occurs entirely on private lands. The essential 
features in this stream may require special management considerations 
or protection due to residual impacts from past livestock grazing and 
impacts to uplands, riparian vegetation, and the stream; water 
diversions; competition with and predation by nonnative aquatic 
species; road construction and maintenance; and channelization.

Unit 7: Blue River Subbasin

    Spikedace and loach minnow. We are including within this unit 106.6 
km (66.3 mi) of the Blue River, Campbell Blue Creek, and Little Blue 
Creek in Greenlee County, Arizona, and portions of Campbell Blue, Pace, 
Frieborn, and Dry Blue creeks in Catron County, New Mexico. The Blue 
River Subbasin is not specifically known to have been occupied by 
spikedace. The Blue River and its tributary streams included within 
this unit are known to have been occupied by loach minnow at listing, 
and are currently occupied by loach minnow (AGFD 1994, pp. 4-14; Bagley 
et al. 1995, multiple survey records;

[[Page 66516]]

Carter 2005, pp. 1-8; Clarkson et al. 2008, pp. 3-4).
    The tributaries Campbell Blue Creek and Little Blue Creek occur 
primarily on Federal lands on the Apache-Sitgreaves National Forests, 
along with a few parcels of private lands. The tributaries Pace Creek 
and Frieborn Creek occur entirely on Federal lands on the Gila National 
Forest in New Mexico. The essential features in these streams may 
require special management considerations or protection due to residual 
effects of past livestock grazing and impacts to uplands, riparian 
vegetation, and the stream; moderate drought (University of Nebraska-
Lincoln 2010, p. 1); and competition with and predation by nonnative 
aquatic species.
    Included within this proposed designation are 81.4 km (50.6 mi) of 
the Blue River from the confluence with the San Francisco River 
upstream to the confluence of Campbell Blue and Dry Blue creeks. Loach 
minnow are known to occur throughout the Blue River, while spikedace 
have not been documented. Because the range of spikedace has been 
severely reduced with only four remaining populations, additional areas 
for expansion of spikedace numbers will be required to ensure the 
survival and recovery of the species. In addition, planning among 
several State and Federal agencies is underway for restoration of 
native fish species, including spikedace, in the Blue River through 
construction of a barrier that will exclude nonnative fish from moving 
upstream. Barrier feasibility studies have been completed, as has a 
draft Memorandum of Understanding with land managers and residents in 
this area. The larger size of this stream, compared to smaller, 
tributary streams within the species' range, along with its perennial 
flows and conservation management activities, present a unique 
opportunity for spikedace. Federal land ownership throughout the 
majority of this proposed critical habitat unit would facilitate 
management for the species. In addition, the Blue River is occupied by 
loach minnow, and contains suitable habitat for all life stages of 
spikedace and loach minnow (PBF 1); has an appropriate food base (PBF 
2); consists of perennial streams with no or low pollutant issues (PBFs 
3 and 4); has no nonnative aquatic species, or levels of nonnative 
aquatic species that are sufficiently low to allow persistence of 
spikedace and loach minnow (PBF 5); and has an appropriate hydrologic 
regime to maintain suitable habitat characteristics (PBF 6). Because of 
its suitability, the Blue River can expand the geographic distribution 
of spikedace, and is therefore essential to its survival and recovery.
    Landownership surrounding the Blue River is primarily Federal lands 
on the Apache-Sitgreaves National Forests, with small parcels of 
private lands. The essential features in this stream may require 
special management considerations or protection due to livestock 
grazing and impacts to uplands, riparian vegetation, and the stream 
(Service 2008); moderate drought (University of Nebraska-Lincoln 2010, 
p.1); water diversions and associated habitat alteration and water 
decreases in the active channel; and road construction and maintenance.
    We are including within this proposal 12.4 km (7.7 mi) of Campbell 
Blue Creek extending from the confluence of Dry Blue and Campbell Blue 
Creeks upstream to the confluence with Coleman Canyon. Above Coleman 
Canyon, the creek changes and becomes steeper and rockier, making it 
unsuitable for spikedace and loach minnow. As with the Blue River, 
Campbell Blue Creek is not known to have been occupied by spikedace. 
Campbell Blue is currently occupied by loach minnow (Carter 2005, pp. 
1-8). Campbell Blue Creek contains suitable habitat for all life stages 
of spikedace and loach minnow (PBF 1); has an appropriate food base 
(PBF 2); consists of perennial flows with no or low levels of 
pollutants (PBFs 3 and 4); has no nonnative aquatic species, or levels 
of nonnative aquatic species that are sufficiently low to allow 
persistence of spikedace and loach minnow (PBF 5); and has an 
appropriate hydrologic regime to maintain suitable habitat 
characteristics (PBF 6). Because it supports more than one PBF and 
serves as an extension of available habitat on the Blue River, Campbell 
Blue Creek is essential to the conservation of spikedace and loach 
minnow.
    We are including within this proposal 5.1 km (3.1 mi) of Little 
Blue Creek. This includes the lower, perennial portions of Little Blue 
Creek extending from the confluence with the Blue River upstream to the 
confluence with a canyon. Above the canyon, flows are not perennial. 
There are no spikedace records from Little Blue Creek; however, it was 
known to be occupied at listing by loach minnow. Little Blue Creek 
contains suitable habitat for all life stages of spikedace and loach 
minnow (PBF 1); has an appropriate food base (PBF 2); consists of 
perennial flows with no or low levels of pollutants (PBFs 3 and 4); and 
has an appropriate hydrologic regime to maintain suitable habitat 
characteristics (PBF 6). Because it supports more than one PBF and 
serves as an extension of available habitat on the Blue River, this 
area is essential to the conservation of spikedace and loach minnow.
    We are including within this proposal 1.2 km (0.8 mi) of Pace Creek 
from the confluence with Dry Blue Creek upstream to a barrier falls. 
Habitat above the barrier is considered unsuitable. There are no known 
records of spikedace from Pace Creek; however, it is currently occupied 
by loach minnow (ASU 2002; NMDGF 2008), and is presumed to have been 
occupied by loach minnow at listing. Its occupancy by loach minnow, a 
species which often co-occurs with spikedace, is also indicative of its 
suitability. Pace Creek contains suitable habitat for all life stages 
of spikedace and loach minnow (PBF 1); has an appropriate food base 
(PBF 2); consists of perennial flows with no or low levels of 
pollutants (PBFs 3 and 4); and has an appropriate hydrologic regime to 
maintain suitable habitat characteristics (PBF 6). Because it supports 
more than one PBF and serves as an extension of available habitat on 
the Blue River, and is currently occupied by loach minnow, this area is 
essential to the conservation of spikedace and loach minnow.
    We are including within this proposal 1.8 km (1.1 mi) of Frieborn 
Creek from the confluence with Dry Blue Creek upstream to an unnamed 
tributary. There are no known records for spikedace in Frieborn Creek; 
however, it is currently occupied by loach minnow. Its occupancy by 
loach minnow, a co-occurring species for spikedace, indicates its 
suitability. Frieborn Creek contains suitable habitat for all life 
stages of spikedace and loach minnow (PBF 1); has an appropriate food 
base (PBF 2); consists of perennial flows with no or low levels of 
pollutants (PBFs 3 and 4); and has an appropriate hydrologic regime to 
maintain suitable habitat characteristics (PBF 6). Because it supports 
more than one PBF and serves as an extension of available habitat on 
the Blue River, this area is essential to the conservation of spikedace 
and loach minnow.
    We are including within this proposal 4.7 km (3.0 mi) of Dry Blue 
Creek from the confluence with Campbell Blue Creek upstream to the 
confluence with Pace Creek. Dry Blue Creek is not known to be occupied 
by spikedace; however, it currently supports loach minnow, a co-
occurring species for spikedace (ASU 2002; NMDGF 2008). Loach minnow 
are presumed to have been present at listing. In addition, Dry Blue 
Creek contains suitable habitat for all life stages of spikedace and 
loach minnow (PBF 1); has an appropriate

[[Page 66517]]

food base (PBF 2); consists of perennial flows with no or low levels of 
pollutants (PBFs 3 and 4); and has an appropriate hydrologic regime to 
maintain suitable habitat characteristics (PBF 6). Because it supports 
more than one PBF and serves as an extension of available habitat on 
the Blue River, this area is essential to the conservation of spikedace 
and loach minnow.
    The essential features in this subbasin may require special 
management considerations or protection due to residual impacts of past 
livestock grazing and impacts to uplands, riparian vegetation, and the 
stream; moderate drought (University of Nebraska-Lincoln 2010, p. 1); 
and competition with and predation by nonnative aquatic species.

Unit 8. Gila River Subbasin

    Spikedace and loach minnow. The upper Gila River subbasin includes 
portions of the mainstem Gila River and four tributaries including West 
Fork Gila River, Middle Fork Gila River, East Fork Gila River, and 
Mangas Creek in Hidalgo, Grant, and Catron Counties, New Mexico. The 
Gila River subbasin also includes the Gila River in Greenlee, Graham, 
Maricopa, and Pinal Counties in Arizona. All streams included within 
this unit were known to be occupied by both species at listing.
    We are including within the proposal 165.1 km (102.6 mi) of the 
Gila River from the confluence with Moore Canyon (near the Arizona-New 
Mexico border) upstream to the confluence of the East and West Forks. 
Below Moore Canyon, the river is substantially altered by agriculture, 
diversion, and urban development. In addition, no spikedace or loach 
minnow records are known from Moore Canyon downstream in Pinal County, 
Arizona. The portions of the Gila River included within the proposed 
designation support the largest remaining populations of spikedace and 
loach minnow (NMDGF 2008; Propst et al. 2009, pp. 14-17). The Gila 
River contains suitable habitat for all life stages of spikedace and 
loach minnow (PBF 1); has an appropriate food base (PBF 2); consists of 
perennial streams with no or low levels of pollutants (PBFs 3 and 4); 
and has an appropriate hydrologic regime to maintain suitable habitat 
characteristics (PBF 6). The mainstem Gila River in New Mexico is 
considered essential to the survival and recovery of the species 
because it supports the largest remaining population of spikedace and 
loach minnow, and contains several of the PBFs for both species.
    Spikedace and loach minnow on the Gila River mainstem occur 
primarily on Federal lands managed by the BLM and the Gila National 
Forest, interspersed with private and State lands. The essential 
features in this stream may require special management considerations 
or protection due to residual impacts of past livestock grazing and 
impacts to uplands, riparian vegetation, and the stream; competition 
with and predation by nonnative aquatic species; road construction and 
maintenance; water diversions; and recreation.
    Portions of streams on the Gila River mainstem within this unit are 
owned and managed by Freeport McMoRan. This area may be considered for 
exclusion from the final critical habitat designation under section 
4(b)(2) of the Act (see ``Application of Section 4(b)(2) of the Act'' 
section below for additional information).
    We are including within the proposal 13.0 km (8.1 mi) of the West 
Fork Gila River from the confluence with the East Fork Gila River 
upstream to the confluence with EE Canyon. Flows throughout this reach 
are perennial. Above EE Canyon, the river becomes unsuitable for 
spikedace and loach minnow due to gradient and channel morphology. The 
West Fork Gila River is currently occupied by both species (NMDGF 2008; 
Propst et al. 2009, pp. 7-9). The West Fork Gila River contains 
suitable habitat for all life stages of spikedace and loach minnow (PBF 
1); has an appropriate food base (PBF 2); consists of perennial streams 
with no or low levels of pollutants (PBFs 3 and 4); and has an 
appropriate hydrologic regime to maintain suitable habitat 
characteristics (PBF 6). This area is considered essential to the 
survival and recovery of spikedace and loach minnow due to its 
historical and current occupancy and multiple PBFs. In addition, the 
West Fork Gila River is connected to habitat occupied by both species 
on the Gila River.
    The West Fork Gila River occurs primarily on a mix of Federal lands 
on the Gila National Forest, the National Park Service, and private 
lands. The essential features in this stream may require special 
management considerations or protection due to competition with and 
predation by nonnative aquatic species, road construction and 
maintenance, and watershed impacts associated with past wildfires.
    We are including within the proposal 42.1 km (26.2 mi) of the East 
Fork Gila River from the confluence with the West Fork Gila River 
upstream to the confluence of Beaver and Taylor Creeks. The East Fork 
Gila River is currently occupied by spikedace and loach minnow (NMDGF 
2008; Propst et al. 2009 pp. 12-13). The East Fork Gila River contains 
suitable habitat for all life stages of spikedace and loach minnow (PBF 
1); has an appropriate food base (PBF 2); consists of perennial flows 
with no or low pollutant levels (PBFs 3 and 4); and has an appropriate 
hydrologic regime to maintain suitable habitat characteristics (PBF 6). 
The East Fork Gila River is essential to the survival and recovery of 
both species because of its historical and current occupancy and 
several PBFs. In addition, the East Fork Gila River is connected to 
habitat occupied by spikedace and loach minnow on the Gila River.
    The East Fork Gila River occurs primarily on Federal lands on the 
Gila National Forest, with small parcels of private lands interspersed. 
The essential features in this stream may require special management 
considerations or protection due to residual impacts of past livestock 
grazing and impacts to uplands, riparian vegetation, and the stream; 
competition with and predation by nonnative aquatic species; and 
watershed impacts associated with past wildfires.
    We are including within the proposal 9.1 km (5.7 mi) of Mangas 
Creek from the confluence with the Gila River upstream to the 
confluence with Willow Creek. Mangas Creek was not specifically known 
to be occupied at listing by spikedace or loach minnow, but is within 
the historical ranges of the species. Mangas Creek is currently 
occupied by spikedace and loach minnow (NMDGF 2008). Mangas Creek 
contains suitable habitat for all life stages of spikedace and loach 
minnow (PBF 1); has an appropriate food base (PBF 2); consists of 
perennial flows with no or low levels of pollutants (PBFs 3 and 4); and 
has an appropriate hydrologic regime to maintain suitable habitat 
characteristics (PBF 6). This area is considered essential to the 
conservation of these species because it is currently occupied, has 
several PBFs, and is connected to portions of the Gila River occupied 
by spikedace and loach minnow.
    Mangas Creek occurs primarily on private lands, occasionally 
crossing the Gila National Forest or State land parcels. The essential 
features in this stream may require special management considerations 
or protection due to dispersed livestock grazing, and potential 
competition with and predation by nonnative aquatic species.
    Portions of the Gila River mainstem and the majority of Mangas 
Creek proposed for inclusion as critical habitat within this unit are 
owned and managed by Freeport McMoRan. These areas may

[[Page 66518]]

be considered for exclusion from the final critical habitat designation 
under section 4(b)(2) of the Act (see ``Application of Section 4(b)(2) 
of the Act'' section below for additional information).
    Spikedace only. The Agua Fria River is located on the extreme 
western edge of the species' range, on the lower portions of the Gila 
River in Yavapai and Maricopa Counties, Arizona. The Agua Fria River 
supports stretches of perennial flows interspersed with sections of 
intermittent flows before entering the Lake Pleasant reservoir created 
by Pleasant Dam. Suitable habitat areas on the Agua Fria River are 
therefore minimal, with perennial stretches mixed with predominantly 
intermittent stretches, and isolated from any mainstem system by a 
large reservoir. The Gila River at the confluence with the Agua Fria 
River is not perennial, so that the Agua Fria River does not act as an 
extension of suitable habitat in the adjacent mainstem river. Due to 
these factors, we cannot conclude that the Agua Fria River is essential 
to the conservation of spikedace at this time.
    We are including within the proposal 12.5 km (7.7 mi) of the Middle 
Fork Gila River extending from the confluence with West Fork Gila River 
upstream to the confluence with Big Bear Canyon. This area is currently 
occupied by spikedace and is connected to currently occupied habitat on 
the West Fork of the Gila River (NMDGF 2008; Propst et al. 2009, pp. 9-
11). The Gila River contains suitable habitat for all life stages of 
spikedace (PBF 1); has an appropriate food base (PBF 2); consists of 
perennial streams with no or low pollutant issues (PBFs 3 and 4); and 
has an appropriate hydrologic regime to maintain suitable habitat 
characteristics (PBF 6). This area is considered essential to the 
survival and recovery of the species because of its historical and 
current occupancy and multiple PBFs. In addition, the Middle Fork Gila 
River is connected to habitat occupied by spikedace on the West Fork 
Gila River.
    The Middle Fork Gila River occurs primarily on Federal lands 
managed by the Gila National Forest, with small parcels of private 
lands interspersed with Federal lands. The essential features in this 
stream may require special management considerations or protection due 
to residual impacts of past livestock grazing and impacts to uplands, 
riparian vegetation, and the stream; competition with and predation by 
nonnative aquatic species; and watershed impacts associated with past 
wildfires.
    Loach minnow only. In addition to the areas described above for 
this unit, we are including within the proposed designation 19.1 km 
(11.9 mi) of the Middle Fork Gila River extending from the confluence 
with West Fork Gila River upstream to the confluence with Brothers West 
Canyon. The 12.5 km (7.7 mi) designated on the Middle Fork Gila River 
for spikedace is completely within this 19.1 km (11.9 mi) designated 
for loach minnow. This area is currently occupied by loach minnow 
(NMDGF 2008; Propst et al. 2009, pp. 9-11). The Middle Fork Gila River 
contains suitable habitat for all life stages of loach minnow (PBF 1); 
has an appropriate food base (PBF 2); consists of perennial flows with 
no or low levels of pollutants (PBFs 3 and 4); and has an appropriate 
hydrologic regime to maintain suitable habitat characteristics (PBF 6). 
This area is considered essential to the survival and recovery of loach 
minnow due to its historical and current occupancy, its multiple PBFs, 
and its connection to the West Fork of the Gila River, which is 
currently occupied by loach minnow. See the description above, 
describing the proposed designation along the West and Middle Forks of 
the Gila River for spikedace for details on land ownership and special 
management needs.
    Loach minnow were found in Bear Creek in 2005 (Schiffmiller 2005, 
pp. 1-4; NMDGF 2008); however, we are not including Bear Creek within 
this proposed designation. Bear Creek contains limited reaches of 
perennial flows in the upstream portions. However, most of the stream 
is intermittent. It is believed that loach minnow detected in 2005 came 
from the Gila River during a period when the upstream, perennial 
section was temporarily connected to the Gila River. However, we do not 
believe this area supports suitable conditions for loach minnow; 
therefore we do not believe this area is occupied on a regular or 
frequent basis. While we have documentation of the species from Bear 
Creek in 2005, there is no evidence of persistence of the species here, 
and the unsuitable habitat conditions indicate that this area is not 
essential to the survival and recovery of loach minnow.

 Table 6--Stream Segments Considered in This Critical Habitat Proposal,
        and the Ruleset Criteria Under Which They Are Identified
------------------------------------------------------------------------
                                Occupied by spikedace and     Ruleset
            Stream              loach minnow at the time    criteria met
                                       of listing                *
------------------------------------------------------------------------
Verde River..................  Yes.......................  1a.
Granite Creek................  No........................  2a, 2c.
Oak Creek....................  No........................  2a.
Beaver and Wet Beaver Creek..  No........................  2a.
Fossil Creek.................  No........................  2a.
West Clear Creek (spikedace    Yes.......................  1a.
 only).
Salt River (spikedace only)..  Yes.......................  1b.
Agua Fria River (spikedace     Yes.......................  1b.
 only).
Tonto Creek (spikedace only).  Yes.......................  1a.
Greenback Creek (spikedace     No........................  2a, 2b.
 only).
Rye Creek (spikedace only)...  No........................  2a, 2b.
Spring Creek (spikedace only)  No........................  2a, 2b.
Rock Creek (spikedace only)..  No........................  2a, 2b.
White River (loach minnow      Yes.......................  1a.
 only).
North Fork White River (loach  Yes.......................  1b.
 minnow only).
East Fork White River (loach   Yes.......................  1a.
 minnow only).
East Fork Black River (loach   Yes.......................  1a.
 minnow only).
North Fork East Fork Black     Yes.......................  1a.
 River (loach minnow only).
Boneyard Creek (loach minnow   Yes.......................  1a.
 only).
Coyote Creek (loach minnow     Yes.......................  1a.
 only).

[[Page 66519]]

 
San Pedro River..............  Yes.......................  1a.
Aravaipa Creek...............  Yes.......................  1a.
Deer Creek...................  Yes (loach minnow)........  1a
                               No (spikedace)............  2a, 2c.
Turkey Creek.................  Yes (loach minnow)........  1a
                               No (spikedace)............  2a, 2c.
Hot Springs Canyon...........  No........................  2a.
Redfield Canyon..............  No........................  2a.
Bass Canyon..................  No........................  2a.
Bonita Creek.................  No........................  2b.
Eagle Creek..................  Yes.......................  1a.
San Francisco River..........  Yes.......................  1a.
Tularosa River (loach minnow   Yes.......................  1a.
 only).
Negrito Creek (loach minnow    Yes.......................  1a.
 only).
Whitewater Creek (loach        Yes.......................  1a.
 minnow only).
Blue River...................  No--spikedace.............  2b
                               Yes--loach minnow.........  1a.
Campbell Blue Creek..........  No--spikedace.............  2b
                               Yes--loach minnow.........  1a.
Little Blue Creek............  No--spikedace.............  2b
                               Yes--loach minnow.........  1a.
Pace Creek...................  No--spikedace.............  2b
                               Yes--loach minnow.........  1a.
Dry Blue Creek...............  No--spikedace.............  2b
                               Yes--loach minnow.........  1a.
Frieborn Creek...............  No--spikedace.............  2b
                               Yes--loach minnow.........  1a.
Gila River...................  Yes.......................  1a.
West Fork Gila River.........  Yes.......................  1a.
Middle Fork Gila River.......  Yes.......................  1a.
East Fork Gila River.........  Yes.......................  1a.
Mangas Creek.................  Yes.......................  1a.
------------------------------------------------------------------------
(*1a) Occupied at listing, and contains one or more of the PBFs.
(1b) Occupied at listing, and no longer supports PBFs or has been
  permanently altered so that recovery is unlikely.
(2a) Not known to be occupied at listing, within the historical range of
  the species, has one or more PBFs and serves as an extension of
  habitat in the unit.
(2b) Not known to be occupied at listing, within the historical range of
  the species, has one or more PBFs, and expands the geographic
  distribution across the range of the species.
(2c) Not known to be occupied at listing, within the historical range of
  the species, has one or more PBFs, and is connected to other occupied
  areas.

Effects of Critical Habitat Designation

Section 7 Consultation

    Section 7(a)(2) of the Act requires Federal agencies, including the 
Service, to ensure that actions they fund, authorize, or carry out are 
not likely to destroy or adversely modify critical habitat. Decisions 
by the Fifth and Ninth Circuits Court of Appeals have invalidated our 
definition of ``destruction or adverse modification'' (50 CFR 402.02) 
(see Gifford Pinchot Task Force v. U.S. Fish and Wildlife Service, 378 
F. 3d 1059 (9th Cir. 2004) and Sierra Club v. U.S. Fish and Wildlife 
Service et al., 245 F.3d 434, 442 (5th Cir. 2001)), and we do not rely 
on this regulatory definition when analyzing whether an action is 
likely to destroy or adversely modify critical habitat. Under the 
statutory provisions of the Act, we determine destruction or adverse 
modification on the basis of whether, with implementation of the 
proposed Federal action, the affected critical habitat would remain 
functional (or retain those PBFs that relate to the ability of the area 
to periodically support the species) to serve its intended conservation 
role for the species.
    If a species is listed or critical habitat is designated, section 
7(a)(2) of the Act requires Federal agencies to ensure that activities 
they authorize, fund, or carry out are not likely to jeopardize the 
continued existence of the species or to destroy or adversely modify 
its critical habitat. If a Federal action may affect a listed species 
or its critical habitat, the responsible Federal agency (action agency) 
must enter into consultation with us. As a result of this consultation, 
we document compliance with the requirements of section 7(a)(2) through 
our issuance of:
    (1) A concurrence letter for Federal actions that may affect, but 
are not likely to adversely affect, listed species or critical habitat; 
or
    (2) A biological opinion for Federal actions that may affect, and 
are likely to adversely affect, listed species or critical habitat.
    When we issue a biological opinion concluding that a project is 
likely to jeopardize the continued existence of a listed species or 
destroy or adversely modify critical habitat, we also provide 
reasonable and prudent alternatives to the project, if any are 
identifiable. We define ``Reasonable and prudent alternatives'' at 50 
CFR 402.02 as alternative actions identified during consultation that:

[[Page 66520]]

     Can be implemented in a manner consistent with the 
intended purpose of the action,
     Can be implemented consistent with the scope of the 
Federal agency's legal authority and jurisdiction,
     Are economically and technologically feasible, and
     Would, in the Director's opinion, avoid jeopardizing the 
continued existence of the listed species or destroying or adversely 
modifying critical habitat.
    Reasonable and prudent alternatives can vary from slight project 
modifications to extensive redesign or relocation of the project. Costs 
associated with implementing a reasonable and prudent alternative are 
similarly variable.
    Regulations at 50 CFR 402.16 require Federal agencies to reinitiate 
consultation on previously reviewed actions in instances where we have 
listed a new species or subsequently designated critical habitat that 
may be affected and the Federal agency has retained discretionary 
involvement or control over the action (or the agency's discretionary 
involvement or control is authorized by law). Consequently, Federal 
agencies may sometimes need to request reinitiation of consultation 
with us on actions for which formal consultation has been completed, if 
those actions with discretionary involvement or control may affect 
subsequently listed species or designated critical habitat.
    Federal activities that may affect spikedace and loach minnow or 
their designated critical habitat require section 7 consultation under 
the Act. Activities on State, Tribal, local, or private lands requiring 
a Federal permit (such as a permit from the U.S. Army Corps of 
Engineers under section 404 of the Clean Water Act (33 U.S.C. 1251 et 
seq.) or a permit from us under section 10 of the Act) or involving 
some other Federal action (such as funding from the Federal Highway 
Administration, Federal Aviation Administration, or the Federal 
Emergency Management Agency) are subject to the section 7 consultation 
process. Federal actions not affecting listed species or critical 
habitat, and actions on State, Tribal, local or private lands that are 
not federally funded, authorized, or permitted, do not require section 
7 consultations.

Application of the Jeopardy and Adverse Modification Standard

Application of the Jeopardy Standard

    Prior to and following listing and designation of critical habitat, 
the Service applies an analytical framework for jeopardy analyses that 
relies heavily on the importance of core area populations to the 
survival and recovery of the species. The section 7(a)(2) analysis is 
focused not only on these populations but also on the habitat 
conditions necessary to support them.
    The jeopardy analysis usually expresses the survival and recovery 
needs of the species in a qualitative fashion without making 
distinctions between what is necessary for survival and what is 
necessary for recovery. Generally, if a proposed Federal action is 
incompatible with the viability of the affected core area 
population(s), inclusive of associated habitat conditions, a jeopardy 
finding is considered to be warranted, because of the relationship of 
each core area population to the survival and recovery of the species 
as a whole.

Application of the ``Adverse Modification'' Standard

    The key factor related to the adverse modification determination is 
whether, with implementation of the proposed Federal action, the 
affected critical habitat would continue to serve its intended 
conservation role for the species, or retain those PBFs that relate to 
the ability of the area to periodically support the species. Activities 
that may destroy or adversely modify critical habitat are those that 
alter the PBFs to an extent that appreciably reduces the conservation 
value of critical habitat for spikedace and loach minnow. As discussed 
above, the role of critical habitat is to support the life-history 
needs of the species and provide for the conservation (including 
recovery) of the species.
    Section 4(b)(8) of the Act requires us to briefly evaluate and 
describe, in any proposed or final regulation that designates critical 
habitat, activities involving a Federal action that may destroy or 
adversely modify such habitat, or that may be affected by such 
designation.
    Activities that, when carried out, funded, or authorized by a 
Federal agency, may affect critical habitat and therefore should result 
in consultation for spikedace and loach minnow include, but are not 
limited to:
    (1) Actions that would diminish flows within the active stream 
channel. Such activities could include, but are not limited to: Water 
diversions, channelization, construction of any barriers or impediments 
within the active river channel, removal of flows in excess of those 
allotted under a given water right, construction of permanent or 
temporary diversion structures, and groundwater pumping within aquifers 
associated with the river. These actions could affect water depth, 
velocity, and flow pattern, all of which are essential to the different 
life stages of spikedace or loach minnow.
    (2) Actions that significantly alter the water chemistry of the 
active channel. Such activities could include, but are not limited to: 
release of chemicals, biological pollutants, or other substances into 
the surface water or connected groundwater at a point source or by 
dispersed release (non-point source); and storage of chemicals or 
pollutants that can be transmitted, via surface water, groundwater, or 
air into critical habitat. These actions can affect water chemistry, 
and in turn the prey base of spikedace and loach minnow.
    (3) Actions that would significantly increase sediment deposition 
within a stream channel. Such activities could include, but are not 
limited to: Excessive sedimentation from livestock overgrazing, road 
construction, commercial or urban development, channel alteration, 
timber harvest, ORV use, recreational use, or other watershed and 
floodplain disturbances. These activities could adversely affect 
reproduction of the species by preventing hatching of eggs, or by 
eliminating suitable habitat for egg placement by loach minnow. In 
addition, excessive levels of sedimentation can make it difficult for 
these species to locate prey.
    (4) Actions that result in the introduction, spread, or 
augmentation of nonnative aquatic species in occupied stream segments, 
or in stream segments that are hydrologically connected to occupied 
stream segments, even if those segments are occasionally intermittent, 
or introduction of other species that compete with or prey on spikedace 
or loach minnow. Possible actions could include, but are not limited 
to: Introduction of parasites or disease, stocking of nonnative fishes, 
stocking of sport fish, stocking of nonnative amphibians, or other 
related actions. These activities can affect the growth, reproduction, 
and survival of spikedace and loach minnow.
    (5) Actions that would significantly alter channel morphology. Such 
activities could include, but are not limited to: Channelization, 
impoundment, road and bridge construction, mining, dredging, and 
destruction of riparian vegetation. These activities may lead to 
changes in water flows and levels that would degrade or eliminate the 
spikedace or loach minnow, their habitats, or both. These actions can 
also lead to increased sedimentation and degradation in water

[[Page 66521]]

quality to levels that are beyond the tolerances of spikedace and loach 
minnow.

Exemptions

Application of Section 4(a)(3) of the Act

    The Sikes Act Improvement Act of 1997 (Sikes Act) (16 U.S.C. 670a) 
required each military installation that includes land and water 
suitable for the conservation and management of natural resources to 
complete an integrated natural resources management plan (INRMP) by 
November 17, 2001. An INRMP integrates implementation of the military 
mission of the installation with stewardship of the natural resources 
found on the base. Each INRMP includes:
     An assessment of the ecological needs on the installation, 
including the need to provide for the conservation of listed species;
     A statement of goals and priorities;
     A detailed description of management actions to be 
implemented to provide for these ecological needs; and
     A monitoring and adaptive management plan.
    Among other things, each INRMP must, to the extent appropriate and 
applicable, provide for fish and wildlife management; fish and wildlife 
habitat enhancement or modification; wetland protection, enhancement, 
and restoration where necessary to support fish and wildlife; and 
enforcement of applicable natural resource laws.
    The National Defense Authorization Act for Fiscal Year 2004 (Pub. 
L. 108-136) amended the Act to limit areas eligible for designation as 
critical habitat. Specifically, section 4(a)(3)(B)(i) of the Act (16 
U.S.C. 1533(a)(3)(B)(i)) now provides: ``The Secretary shall not 
designate as critical habitat any lands or other geographical areas 
owned or controlled by the Department of Defense, or designated for its 
use, that are subject to an integrated natural resources management 
plan prepared under section 101 of the Sikes Act (16 U.S.C. 670a), if 
the Secretary determines in writing that such plan provides a benefit 
to the species for which critical habitat is proposed for 
designation.''
    There are no Department of Defense lands within the proposed 
designation.

Exclusions

Application of Section 4(b)(2) of the Act

    Section 4(b)(2) of the Act states that the Secretary must designate 
and revise critical habitat on the basis of the best available 
scientific data after taking into consideration the economic impact, 
national security impact, and any other relevant impact of specifying 
any particular area as critical habitat. The Secretary may exclude an 
area from critical habitat if he determines that the benefits of such 
exclusion outweigh the benefits of specifying such area as part of the 
critical habitat, unless he determines, based on the best scientific 
data available, that the failure to designate such area as critical 
habitat will result in the extinction of the species. In making that 
determination, the legislative history is clear that the Secretary has 
broad discretion regarding which factor(s) to use and how much weight 
to give to any factor.
    Under section 4(b)(2) of the Act, we may exclude an area from 
designated critical habitat based on economic impacts, impacts on 
national security, or any other relevant impacts. In considering 
whether to exclude a particular area from the proposed designation, we 
must identify the benefits of including the area in the proposed 
designation, identify the benefits of excluding the area from the 
proposed designation, and determine whether the benefits of exclusion 
outweigh the benefits of inclusion. If, based on this analysis, we make 
this determination, then we can exclude areas only if such exclusion 
would not result in the extinction of the species.
    When considering the benefits of inclusion for an area, we consider 
the additional regulatory benefits that area would receive from the 
protection from adverse modification or destruction as a result of 
actions with a Federal nexus, the educational benefits of mapping 
essential habitat for recovery of the listed species, and any benefits 
that may result from a designation due to State or Federal laws that 
may apply to critical habitat.
    When considering the benefits of exclusion, we consider, among 
other things, whether exclusion of a specific area is likely to result 
in conservation; the continuation, strengthening, or encouragement of 
partnerships; implementation of a management plan that provides equal 
to or more conservation that a critical habitat designation would 
provide; or some combination of these.
    After evaluating the benefits of inclusion and the benefits of 
exclusion, we carefully weigh the two sides to determine if the 
benefits of exclusion outweigh those of inclusion. If we determine that 
they do, we then determine whether exclusion would result in extinction 
of the species. If exclusion of an area from critical habitat will 
result in extinction, we will not exclude it from the designation.
Exclusions Based on Economic Impacts
    Under section 4(b)(2) of the Act, we are required to consider the 
economic impacts of specifying any particular area as critical habitat. 
In order to consider economic impacts, we are preparing an analysis of 
the economic impacts of the proposed critical habitat designation and 
related factors. An economic analysis was completed for the 2007 
designation of spikedace and loach minnow critical habitat (72 FR 
13355, March 21, 2007). This analysis concluded, in part, that there 
would be potential impacts on several economic activities, including 
water diversion repair, livestock grazing, recreation, species 
management, residential and commercial development, and transportation, 
as well as administrative costs associated with species conservation 
activities. A new economic analysis will be completed on this currently 
proposed designation.
    We will announce the availability of the draft economic analysis as 
soon as it is completed, at which time we will seek public review and 
comment. At that time, copies of the draft economic analysis will be 
available for downloading from the Internet at http://www.regulations.gov, or by contacting the Arizona Ecological Services 
Office directly (see FOR FURTHER INFORMATION CONTACT section). During 
the development of a final designation, we will consider economic 
impacts, public comments, and other new information, and areas may be 
excluded from the final critical habitat designation under section 
4(b)(2) of the Act and our implementing regulations at 50 CFR 424.19.
Exclusions Based on National Security Impacts
    Under section 4(b)(2) of the Act, we consider whether there are 
lands owned or managed by the Department of Defense (DOD) where a 
national security impact might exist. In preparing this proposal, we 
determined that the lands within the proposed designation of critical 
habitat for spikedace and loach minnow are not owned or managed by the 
DOD, and therefore we anticipate no impacts to national security. We 
are not considering any areas for exclusion from the final critical 
habitat designation based on impacts on national security.
Exclusions Based on Other Relevant Impacts
    Under section 4(b)(2) of the Act, we consider any other relevant 
impacts, in addition to economic impacts and impacts to national 
security. We consider a number of factors including

[[Page 66522]]

whether the landowners have developed any HCPs or other management 
plans for the area, or whether there are conservation partnerships that 
would be encouraged by designation of, or exclusion from, critical 
habitat. In addition, we look at any Tribal issues, and consider the 
government-to-government relationship of the United States with Tribal 
entities. We also consider any social impacts that might occur because 
of the designation.
    When we evaluate the existence of a conservation plan when 
considering the benefits of exclusion, we consider a variety of 
factors, including but not limited to, whether the plan is finalized; 
how it provides for the conservation of the essential physical and 
biological features; whether there is a reasonable expectation that the 
conservation management strategies and actions contained in a 
management plan will be implemented into the future; whether the 
conservation strategies in the plan are likely to be effective; and 
whether the plan contains a monitoring program or adaptive management 
to ensure that the conservation measures are effective and can be 
adapted in the future in response to new information.
    During the preparation of the 2007 critical habitat designation (72 
FR 13355, March 21, 2007), we received management plans from the White 
Mountain Apache Tribe, San Carlos Apache Tribe, and Freeport McMoRan 
(formerly Phelps Dodge). Additionally, a Tribal Resolution was prepared 
by the Yavapai Apache Nation. Areas covered by these plans and the 
resolution were excluded from the previous final critical habitat 
designation. On October 3, 2008, a formal opinion was issued by the 
Solicitor of the Department of the Interior, ``The Secretary's 
Authority to Exclude Areas from a Critical Habitat Designation under 
Section 4(b)(2) of the Endangered Species Act'' (U.S. Department of the 
Interior 2008). The opinion clearly lays out that areas which are under 
consideration for exclusion from critical habitat under section 4(b)(2) 
of the Act should be included in the proposed rule and excluded from 
the final rule. Thus, the areas that we excluded from the 2007 
designation may not be automatically excluded from this new proposal, 
but must be reconsidered for exclusion during the new final designation 
process. We will consider these materials and any other relevant 
information pertaining to these entities during the development of the 
final rule to determine if any of these areas should be excluded from 
the final critical habitat designation under section 4(b)(2) of the 
Act.
    Finally, portions of the Verde River are included in the area 
covered by the Salt River Project's HCP. We will consider the HCP and 
any other relevant information during the development of the final rule 
to determine if this area should be excluded from the final critical 
habitat designation under section 4(b)(2) of the Act.
    A final determination on whether we should exclude any of these 
areas from critical habitat for the spikedace and loach minnow will be 
made when we publish the final rule designating critical habitat. We 
will take into account public comments and carefully weigh the benefits 
of exclusion versus inclusion of these areas. We may also consider 
areas not identified above for exclusion from the final critical 
habitat designation based on information we may receive during the 
preparation of the final rule (e.g., management plans for additional 
areas).

Peer Review

    In accordance with our joint policy published in the Federal 
Register on July 1, 1994 (59 FR 34270), we will seek the expert 
opinions of at least three appropriate and independent specialists 
regarding this proposed rule. The purpose of peer review is to ensure 
that our critical habitat designation is based on scientifically sound 
data, assumptions, and analyses. We will invite these peer reviewers to 
comment during this public comment period on our specific assumptions 
and conclusions in this proposed designation of critical habitat.
    We will consider all comments and information we receive during 
this comment period on this proposed rule during our preparation of a 
final determination. Accordingly, the final decision may differ from 
this proposal.

Public Hearings

    Section 4(b)(5)(E) of the Act requires us to hold at least one 
public hearing on this proposal, if properly requested. Requests for 
public hearings must be made in writing within 45 days of the 
publication of this proposal in the Federal Register (see DATES). We 
will schedule public hearings on this proposal, if any are requested, 
and announce the dates, times, and places of those hearings in the 
Federal Register and local newspapers at least 15 days prior to the 
first hearing.

Required Determinations

Regulatory Planning and Review--Executive Order 12866

    The Office of Management and Budget (OMB) has determined that this 
rule is not significant under Executive Order 12866 (E.O. 12866). OMB 
bases its determination upon the following four criteria:
    (a) Whether the rule will have an annual effect of $100 million or 
more on the economy or adversely affect an economic sector, 
productivity, jobs, the environment, or other units of the government.
    (b) Whether the rule will create inconsistencies with other Federal 
agencies' actions.
    (c) Whether the rule will materially affect entitlements, grants, 
user fees, loan programs, or the rights and obligations of their 
recipients.
    (d) Whether the rule raises novel legal or policy issues.

Regulatory Flexibility Act

    Under the Regulatory Flexibility Act (RFA; 5 U.S.C. 601 et seq., as 
amended by the Small Business Regulatory Enforcement Fairness Act 
(SBREFA) of 1996), whenever an agency must publish a notice of 
rulemaking for any proposed or final rule, it must prepare and make 
available for public comment a regulatory flexibility analysis that 
describes the effects of the rule on small entities (small businesses, 
small organizations, and small government jurisdictions). However, no 
regulatory flexibility analysis is required if the head of the agency 
certifies the rule will not have a significant economic impact on a 
substantial number of small entities. The SBREFA amended RFA to require 
Federal agencies to provide a certification statement of the factual 
basis for certifying that the rule will not have a significant economic 
impact on a substantial number of small entities.
    At this time, we lack the available economic information necessary 
to provide an adequate factual basis for the required RFA finding. 
Therefore, we defer the RFA finding until completion of the draft 
economic analysis prepared under section 4(b)(2) of the Act and E.O. 
12866. This draft economic analysis and any public comment on these 
issues will provide the required factual basis for the RFA finding. 
Therefore, upon completion of the draft economic analysis, we will 
announce availability of the draft economic analysis of the proposed 
designation in the Federal Register and reopen the public comment 
period for the proposed designation. We will include with this 
announcement, as appropriate, an initial regulatory flexibility 
analysis or a certification that the rule will not have a significant 
economic impact on a substantial number of small entities accompanied 
by the factual basis for that determination.

[[Page 66523]]

Unfunded Mandates Reform Act

    In accordance with the Unfunded Mandates Reform Act (2 U.S.C. 1501 
et seq.), we make the following findings:
    (a) This rule will not produce a Federal mandate. In general, a 
Federal mandate is a provision in legislation, statute, or regulation 
that would impose an enforceable duty upon State, local, or Tribal 
governments, or the private sector, and includes both ``Federal 
intergovernmental mandates'' and ``Federal private sector mandates.'' 
These terms are defined in 2 U.S.C. 658(5)-(7). ``Federal 
intergovernmental mandate'' includes a regulation that ``would impose 
an enforceable duty upon State, local, or tribal governments'' with two 
exceptions. It excludes ``a condition of Federal assistance.'' It also 
excludes ``a duty arising from participation in a voluntary Federal 
program,'' unless the regulation ``relates to a then-existing Federal 
program under which $500,000,000 or more is provided annually to State, 
local, and tribal governments under entitlement authority,'' if the 
provision would ``increase the stringency of conditions of assistance'' 
or ``place caps upon, or otherwise decrease, the Federal Government's 
responsibility to provide funding,'' and the State, local, or Tribal 
governments ``lack authority'' to adjust accordingly. At the time of 
enactment, these entitlement programs were: Medicaid; Aid to Families 
with Dependent Children work programs; Child Nutrition; Food Stamps; 
Social Services Block Grants; Vocational Rehabilitation State Grants; 
Foster Care, Adoption Assistance, and Independent Living; Family 
Support Welfare Services; and Child Support Enforcement. ``Federal 
private sector mandate'' includes a regulation that ``would impose an 
enforceable duty upon the private sector, except (i) a condition of 
Federal assistance or (ii) a duty arising from participation in a 
voluntary Federal program.''
    The designation of critical habitat does not impose a legally 
binding duty on non-Federal Government entities or private parties. 
Under the Act, the only regulatory effect is that Federal agencies must 
ensure that their actions do not destroy or adversely modify critical 
habitat under section 7. While non-Federal entities that receive 
Federal funding, assistance, or permits, or that otherwise require 
approval or authorization from a Federal agency for an action, may be 
indirectly impacted by the designation of critical habitat, the legally 
binding duty to avoid destruction or adverse modification of critical 
habitat rests squarely on the Federal agency. Furthermore, to the 
extent that non-Federal entities are indirectly impacted because they 
receive Federal assistance or participate in a voluntary Federal aid 
program, the Unfunded Mandates Reform Act would not apply, nor would 
critical habitat shift the costs of the large entitlement programs 
listed above onto State governments.
    (b) We lack the available economic information to determine if a 
Small Government Agency Plan is required. Therefore, we defer this 
finding until completion of the draft economic analysis prepared under 
section 4(b)(2) of the Act.

Takings

    In accordance with E.O. 12630 (Government Actions and Interference 
with Constitutionally Protected Private Property Rights), we will 
analyze the potential takings implications of designating critical 
habitat for the spikedace and the loach minnow in a takings 
implications assessment. Following completion of the proposed rule, a 
draft Economic Analysis will be completed for the proposed designation. 
The draft Economic Analysis will provide the foundation for us to use 
in preparing a takings implications assessment.

Federalism

    In accordance with E.O. 13132 (Federalism), this proposed rule does 
not have significant Federalism effects. A Federalism assessment is not 
required. In keeping with Department of the Interior and Department of 
Commerce policy, we requested information from, and coordinated 
development of, this proposed critical habitat designation with 
appropriate State resource agencies in Arizona and New Mexico, and 
Tribal governments. The designation may have some benefit to these 
governments because the areas that contain the features essential to 
the conservation of the species are more clearly defined, and the 
physical and biological features of the habitat necessary for the 
conservation of the species are specifically identified. This 
information does not alter where and what federally sponsored 
activities may occur. However, it may assist local governments in long-
range planning (rather than having them wait for case-by-case section 7 
consultations to occur).
    Where State and local governments require approval or authorization 
from a Federal agency for actions that may affect critical habitat, 
consultation under section 7(a)(2) would be required. While non-Federal 
entities that receive Federal funding, assistance, or permits, or that 
otherwise require approval or authorization from a Federal agency for 
an action, may be indirectly impacted by the designation of critical 
habitat, the legally binding duty to avoid destruction or adverse 
modification of critical habitat rests squarely on the Federal agency.

Civil Justice Reform

    In accordance with E.O. 12988 (Civil Justice Reform), the Office of 
the Solicitor has determined that the rule does not unduly burden the 
judicial system and that it meets the requirements of sections 3(a) and 
3(b)(2) of the Order. We have proposed designating critical habitat in 
accordance with the provisions of the Act. This proposed rule uses 
standard property descriptions and identifies the physical and 
biological features within the designated areas to assist the public in 
understanding the habitat needs of the spikedace and the loach minnow.

Paperwork Reduction Act of 1995

    This rule does not contain any new collections of information that 
require approval by OMB under the Paperwork Reduction Act of 1995 (44 
U.S.C. 3501 et seq.). This rule will not impose recordkeeping or 
reporting requirements on State or local governments, individuals, 
businesses, or organizations. An agency may not conduct or sponsor, and 
a person is not required to respond to, a collection of information 
unless it displays a currently valid OMB control number.

National Environmental Policy Act (NEPA)

    It is our position that, outside the jurisdiction of the U.S. Court 
of Appeals for the Tenth Circuit, we do not need to prepare 
environmental analyses as defined by NEPA (42 U.S.C. 4321 et seq.) in 
connection with designating critical habitat under the Act. We 
published a notice outlining our reasons for this determination in the 
Federal Register on October 25, 1983 (48 FR 49244). This position was 
upheld by the U.S. Court of Appeals for the Ninth Circuit (Douglas 
County v. Babbitt, 48 F.3d 1495 (9th Cir. 1995), cert. denied 516 U.S. 
1042 (1996)). However, when the range of the species includes States 
within the Tenth Circuit, such as that of the spikedace and the loach 
minnow, under the Tenth Circuit ruling in Catron County Board of 
Commissioners v. U.S. Fish and Wildlife Service, 75 F.3d 1429 (10th 
Cir. 1996), we will undertake a NEPA analysis for critical habitat 
designation and notify the public of the availability of the draft 
environmental

[[Page 66524]]

assessment for this proposal when it is finished.

Clarity of the Rule

    We are required by Executive Orders 12866 and 12988 and by the 
Presidential Memorandum of June 1, 1998, to write all rules in plain 
language. This means that each rule we publish must:
    (a) Be logically organized;
    (b) Use the active voice to address readers directly;
    (c) Use clear language rather than jargon;
    (d) Be divided into short sections and sentences; and
    (e) Use lists and tables wherever possible.
    If you feel that we have not met these requirements, send us 
comments by one of the methods listed in the ADDRESSES section. To 
better help us revise the rule, your comments should be as specific as 
possible. For example, you should tell us the numbers of the sections 
or paragraphs that are unclearly written, which sections or sentences 
are too long, the sections where you feel lists or tables would be 
useful, etc.

Government-to-Government Relationship With Tribes

    In accordance with the President's memorandum of April 29, 1994, 
Government-to-Government Relations with Native American Tribal 
Governments (59 FR 22951), E.O. 13175, and the Department of the 
Interior's manual at 512 DM 2, we readily acknowledge our 
responsibility to communicate meaningfully with recognized Federal 
Tribes on a government-to-government basis. In accordance with 
Secretarial Order 3206 of June 5, 1997 ``American Indian Tribal Rights, 
Federal-Tribal Trust Responsibilities, and the Endangered Species 
Act'', we readily acknowledge our responsibilities to work directly 
with Tribes in developing programs for healthy ecosystems, to 
acknowledge that tribal lands are not subject to the same controls as 
Federal public lands, to remain sensitive to Indian culture, and to 
make information available to Tribes.
    For this proposal, we are including stream portions of the White 
River and East Fork White River on lands belonging to the White 
Mountain Apache Tribe; portions of Eagle Creek on lands belonging to 
the San Carlos Apache Tribe; and portions of the Verde River on lands 
belonging to the Yavapai-Apache Nation. We are including these areas 
because we have found them to be essential to the survival and recovery 
of the species.
    During the process of developing the 2007 designation of critical 
habitat for spikedace and loach minnow, the Yavapai Apache Nation 
submitted a Tribal Resolution, while the White Mountain Apache and San 
Carlos Apache tribes submitted management plans. Based on these plans, 
we excluded critical habitat on their lands from the previous final 
designation. We have notified the Tribes that a new critical habitat 
proposal is underway, and provided them with information on the 
timeline. We anticipate working with all three entities to address 
river systems on their lands prior to publication of a final rule. 
Additionally, these areas may again be considered for exclusion from 
the final critical habitat designation under section 4(b)(2) of the Act 
(see ``Application of Section 4(b)(2) of the Act'' section above for 
additional information).

Energy Supply, Distribution, or Use

    On May 18, 2001, the President issued an Executive Order (E.O. 
13211; Actions Concerning Regulations That Significantly Affect Energy 
Supply, Distribution, or Use) on regulations that significantly affect 
energy supply, distribution, and use. E.O. 13211 requires agencies to 
prepare Statements of Energy Effects when undertaking certain actions. 
We do not expect this action to significantly affect energy supplies, 
distribution, or use. One project, the SunZia Southwest Transmission 
Project, is currently in the study phase. This project involves the 
construction of up to two 500 kV transmission lines with key 
interconnections to the existing extra-high voltage grid in Arizona and 
New Mexico. The specific route of the transmission lines has not yet 
been determined, and may or may not cross critical habitat proposed in 
this rule (AGFD 2010, p. 1). Alternative alignments, which would not 
cross proposed critical habitat areas, are under consideration (Service 
2010, p. 5). Therefore, this action is not a significant energy action, 
and no Statement of Energy Effects is required. However, we will 
further evaluate this issue as we conduct our economic analysis, and 
review and revise this assessment as warranted.

References Cited

    A complete list of references cited is available on the Internet at 
http://www.regulations.gov and upon request from the Arizona Ecological 
Services Office (see FOR FURTHER INFORMATION CONTACT).

Authors

    The primary authors of this package are the staff members of the 
Arizona Ecological Services Office.

List of Subjects in 50 CFR Part 17

    Endangered and threatened species, Exports, Imports, Reporting and 
recordkeeping requirements, Transportation.

Proposed Regulation Promulgation

    Accordingly, we propose to amend part 17, subchapter B of chapter 
I, title 50 of the Code of Federal Regulations, as set forth below:

PART 17--ENDANGERED AND THREATENED WILDLIFE AND PLANTS

    1. The authority citation for part 17 continues to read as follows:

    Authority:  16 U.S.C. 1361-1407; 16 U.S.C. 1531-1544; 16 U.S.C. 
4201-4245; Pub. L. 99-625, 100 Stat. 3500; unless otherwise noted.

    2. In Sec.  17.11(h), revise the entries for ``Spikedace'' and 
``Minnow, loach'' under ``FISHES'' in the List of Endangered and 
Threatened Wildlife to read as follows:


Sec.  17.11  Endangered and threatened wildlife.

* * * * *
    (h) * * *

--------------------------------------------------------------------------------------------------------------------------------------------------------
                        Species                                                    Vertebrate
--------------------------------------------------------                        population where                       When       Critical     Special
                                                           Historic  range       endangered or         Status         listed      habitat       rules
           Common name                Scientific name                              threatened
--------------------------------------------------------------------------------------------------------------------------------------------------------
 
                                                                      * * * * * * *
              Fishes
 
                                                                      * * * * * * *
Minnow, loach....................  Tiaroga cobitis.....  U.S.A. (AZ, NM),     Entire.............  E               ...........     17.95(e)           NA
                                                          Mexico.
 

[[Page 66525]]

 
                                                                      * * * * * * *
Spikedace........................  Meda fulgida........  U.S.A. (AZ, NM),     Entire.............  E               ...........     17.95(e)           NA
                                                          Mexico.
 
                                                                      * * * * * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------

Sec.  17.44  [Amended]

    3. In Sec.  17.44, remove and reserve paragraphs (p) and (q).
    4. In Sec.  17.95, amend paragraph (e) by revising the entries for 
``Spikedace (Meda fulgida),''and ``Loach Minnow (Tiaroga cobitis)'' to 
read as follows:


Sec.  17.95  Critical habitat--fish and wildlife.

* * * * *
    (e) Fishes.
* * * * *
Loach Minnow (Tiaroga cobitis)
    (1) Critical habitat units are depicted for Apache, Cochise, Gila, 
Graham, Greenlee, Navajo, Pinal, and Yavapai Counties, Arizona, and for 
Catron, Grant, and Hidalgo Counties, New Mexico, on the maps below.
    (2) The physical and biological features of critical habitat for 
the loach minnow are:
    (i) Habitat to support all egg, larval, juvenile, and adult loach 
minnow. This habitat includes perennial flows with a stream depth of 
generally less than 1 m (3.3 ft), and with slow to swift flow 
velocities between 0 and 80 cm per second (0.0 and 31.5 in. per 
second). Appropriate microhabitat types include pools, runs, riffles, 
and rapids over sand, gravel, cobble, and rubble substrates with low or 
moderate amounts of fine sediment and substrate embeddedness. 
Appropriate habitats have a low gradient of less than 2.5 percent, and 
are at elevations below 2,500 m (8,202 ft). Water temperatures should 
be in the general range of 8.0 to 25.0 [deg]C (46.4 to 77 [deg]F);
    (ii) An abundant aquatic insect food base consisting of mayflies, 
true flies, black flies, caddisflies, stoneflies, and dragonflies.
    (iii) Streams with no or no more than low levels of pollutants.
    (iv) Perennial flows, or interrupted stream courses that are 
periodically dewatered but that serve as connective corridors between 
occupied or seasonally occupied habitat and through which the species 
may move when the habitat is wetted.
    (v) No nonnative aquatic species, or levels of nonnative aquatic 
species that are sufficiently low to allow persistence of loach minnow.
    (vi) Streams with a natural, unregulated flow regime that allows 
for periodic flooding or, if flows are modified or regulated, a flow 
regime that allows for adequate river functions, such as flows capable 
of transporting sediments.
    (3) We have determined that all designated areas contain at least 
one PBF for loach minnow. There are no developed areas within the 
designation except for manmade barriers constructed on streams, low 
water road crossings of streams, and areas beneath bridges, all of 
which do not remove the suitability of these areas for this species. 
Where a manmade structure is within the proposed critical habitat 
designation, the structure would be considered to be proposed critical 
habitat if it continues to contain one or more of the PBFs. If the 
structure does not contain one or more of the PBFs, the structure is 
excluded by text in this proposed rule. For excluded structures, a 
Federal action involving these lands (if and when designated) would not 
trigger section 7 consultation with respect to critical habitat and the 
prohibition of destruction or adverse modification, unless the specific 
action may affect adjacent critical habitat.
    (4) Each stream segment includes a lateral component that consists 
of 300 feet (91.4 meters) on either side of the stream channel measured 
from the stream edge at bank full discharge. This lateral component of 
critical habitat contains and contributes to the physical and 
biological features essential to the loach minnow and is intended as a 
surrogate for the 100-year floodplain.
    (5) Critical habitat map units. Data layers defining map units were 
created on a base of USGS 7.5' quadrangles along with shapefiles 
generated by the Arizona Land Resource Information Service for land 
ownership, streams, counties, and the Public Land Survey System. 
Information on species locations was derived from databases developed 
by the Arizona Game and Fish Department, the New Mexico Department of 
Game and Fish, and Arizona State University.
    (6) Note: Index map for loach minnow critical habitat units 
follows.
BILLING CODE 4310-55-P

[[Page 66526]]

[GRAPHIC] [TIFF OMITTED] TP28OC10.000

    (7) Unit 1: Verde River Subbasin, Yavapai County, Arizona.
    (i) Verde River for approximately 119.7 km (74.4 mi), extending 
from the confluence with Beaver and Wet Beaver Creek in Township 14 
North, Range 5 East, southeast quarter of section 30 upstream to 
Sullivan Dam in Township 17 North, Range 2 West, northwest quarter of 
section 15.
    (ii) Granite Creek for approximately 3.2 km (2.0 mi), extending 
from the confluence with the Verde River in Township 17 North, Range 2 
West, northeast quarter of section 14 upstream to a spring in Township 
17 North, Range 2 West, southwest quarter of the southwest quarter of 
section 13.
    (iii) Oak Creek for approximately 54.3 km (33.7 mi), extending from 
the confluence with the Verde River in Township 15 North, Range 4 East, 
southeast quarter of section 20 upstream to the confluence with an 
unnamed

[[Page 66527]]

tributary from the south in Township 17 North, Range 5 East, southeast 
quarter of the northeast quarter of section 24.
    (iv) Beaver Creek and Wet Beaver Creek for approximately 33.5 km 
(20.8 mi), extending from the confluence with the Verde River in 
Township 14 North, Range 5 East, southeast quarter of section 30 
upstream to the confluence with Casner Canyon in Township 15 North, 
Range 6 East, northwest quarter of section 23.
    (v) Fossil Creek for approximately 7.5 km (4.7 mi) extending from 
the confluence with the Verde River in Township 11 North, Range 5 East, 
northeast quarter of section 25 upstream to the confluence with an 
unnamed tributary from the northwest in Township 11.5 North, Range 7 
East, center of section 29.
    (vi) Note: Map of Unit 1, Verde River Subbasin (Map 2), follows.
    [GRAPHIC] [TIFF OMITTED] TP28OC10.001
    

[[Page 66528]]


    (8) Unit 2: Salt River Subbasin, Apache, Gila, and Navajo Counties, 
Arizona.
    (i) White River for approximately 29.0 km (18.0 mi) from the 
confluence with the Black River at Township 4.5 North, Range 20 East, 
northeast quarter of section 35 upstream to the confluence with the 
North and East Forks of the White River at Township 5 North, Range 22 
East, northwest quarter of section 35.
    (ii) East Fork White River for approximately 17.2 km (10.7 mi) from 
the confluence with North Fork White River at Township 5 North, Range 
22 East, northeast quarter of section 35 upstream to the confluence 
with Bones Canyon at Township 5 North, Range 24 East, southwest quarter 
of section 18.
    (iii) East Fork Black River for approximately 19.1 km (11.9 mi) 
from the confluence with the West Fork Black River at Township 4 North, 
Range 28 East, southeast quarter of section 11 upstream to the 
confluence with an unnamed tributary approximately 0.82 km (0.51 mi) 
downstream of the Boneyard Creek confluence at Township 5 North, Range 
29 East, northwest quarter of Section 5.
    (iv) North Fork East Fork Black River for approximately 7.1 km (4.4 
mi) of the North Fork East Fork Black River extending from the 
confluence with East Fork Black River at Township 5 North, Range 29 
East, northwest quarter of section 5 upstream to the confluence with an 
unnamed tributary at Township 6 North, Range 29 East, center of Section 
30.
    (v) Boneyard Creek for approximately 2.3 km (1.4 mi) extending from 
the confluence with the East Fork Black River at Township 5 North, 
Range 29 East, SW quarter of section 5 upstream to the confluence with 
an unnamed tributary at Township 6 North, Range 29 East, southeast 
quarter of section 32.
    (vi) Coyote Creek for approximately 3.4 km (2.1 mi) from the 
confluence with East Fork Black River at Township 5 North, Range 29 
East, northeast quarter of section 8 upstream to an unnamed confluence 
at Township 5 North, Range 29 East, northwest quarter of section 10.
    (vii) Note: Map of Unit 2, Salt River Subbasin (Map 3), follows.

[[Page 66529]]

[GRAPHIC] [TIFF OMITTED] TP28OC10.002

    (9) Unit 3: San Pedro Subbasin, Cochise, Pinal, and Graham 
Counties, Arizona.
    (i) San Pedro River for approximately 60.0 km (37.2 mi) extending 
from the International Boundary with Mexico in Township 24 South, Range 
22 East, section 19 downstream to the confluence with the Babocomari 
River in the San Juan de las Boquillas y Nogales land grant.
    (ii) Aravaipa Creek for approximately 44.9 km (27.9 mi) extending 
from the confluence with the San Pedro River in Township 7 South, Range 
16 East, center of section 9 upstream to the confluence with Stowe 
Gulch in Township 6 South, Range 19 East, southeast quarter of the 
northeast quarter of section 35.
    (iii) Deer Creek--3.7 km (2.3 mi) of the creek extending from the 
confluence with Aravaipa Creek at Township 6 South, Range 18 East, 
section 14

[[Page 66530]]

upstream to the boundary of the Aravaipa Wilderness at Township 6 
South, range 19 East, section 18.
    (iv) Turkey Creek--4.3 km (2.7 mi) of the creek extending from the 
confluence with Aravaipa Creek at Township 6 South, Range 19 East, 
section 19 upstream to the confluence with Oak Grove Canyon at Township 
6 South, Range 19 east, section 32.
    (v) Hot Springs Canyon for approximately 19.0 km (11.8 mi) 
extending from the confluence with the San Pedro River in Township 13 
South, Range 19 East, center of section 23 upstream to the confluence 
with Bass Canyon in Township 12 South, Range 20 East, northeast quarter 
of section 36.
    (vi) Redfield Canyon for approximately 22.5 km (14.0 mi) extending 
from the confluence with the San Pedro River in Township 11 South, 
Range 18 East, southwest quarter of section 34 upstream to the 
confluence with Sycamore Canyon in Township 11 South, Range 20 East, 
northwest quarter of section 28.
    (vii) Bass Canyon for approximately 5.5 km (3.4 mi) from the 
confluence with Hot Springs Canyon in Township 12 South, Range 20 East, 
northeast quarter of section 36 upstream to the confluence with Pine 
Canyon in Township 12 South, Range 21 East, center of section 20.
    (viii) Note: Map of Unit 3, San Pedro River Subbasin (Map 4), 
follows.

[[Page 66531]]

[GRAPHIC] [TIFF OMITTED] TP28OC10.003

    (10) Unit 4: Bonita Creek Subbasin, Graham County, Arizona.
    (i) Bonita Creek for approximately 23.8 km (14.8 mi) from the 
confluence with the Gila River in Township 6 South, Range 28 East, 
southeast quarter of section 21 upstream to the confluence with 
Martinez Wash in Township 4 South, Range 27 East, southeast quarter of 
section 27.
    (ii) Note: Map of Unit 4, Bonita Creek Subbasin (Map 5), follows.

[[Page 66532]]

[GRAPHIC] [TIFF OMITTED] TP28OC10.004

    (11) Unit 5: Eagle Creek Subbasin, Graham and Greenlee Counties, 
Arizona.
    (i) Eagle Creek for approximately 75.5 km (46.9 mi) from the 
Freeport McMoRan diversion dam at Township 4 South, Range 28 East, 
southwest quarter of the northwest quarter of section 23 upstream to 
the confluence of East Eagle Creek in Township 2 North, Range 28 East, 
southwest quarter of section 20.
    (ii) Note: Map of Unit 5, Eagle Creek Subbasin (Map 6), follows.

[[Page 66533]]

[GRAPHIC] [TIFF OMITTED] TP28OC10.005

    (12) Unit 6: San Francisco River Subbasin, Greenlee County, 
Arizona, and Catron County, New Mexico.
    (i) San Francisco River for approximately 181.0 km (112.3 mi) of 
the San Francisco River extending from the confluence with the Gila 
River in Township 5 South, Range 29 East, southeast quarter of section 
21 upstream to the confluence with the Tularosa River in Township 7 
South, Range 19 West, southwest quarter of Section 23.
    (ii) Tularosa River for approximately 30.0 km (18.6 mi) from the 
confluence with the San Francisco River at Township 7 South, Range 19 
West, southwest quarter of section 23 upstream to the town of Cruzville 
at Township 6 South, Range 18 West, southern boundary of section 1.
    (iii) Negrito Creek for approximately 6.8 km (4.2 mi) extending 
from the confluence with the Tularosa River at Township 7 South, Range 
18 West,

[[Page 66534]]

southwest quarter of the northwest quarter of section 19 upstream to 
the confluence with Cerco Canyon at Township 7 South, Range 18 West, 
west boundary of section 22.
    (iv) Whitewater Creek for approximately 1.9 km (1.2 mi) from the 
confluence with the San Francisco River at Township 11 South, Range 20 
West, Section 27 upstream to the confluence with Little Whitewater 
Creek at Township 11 South, Range 20 West, southeast quarter of section 
23.
    (v) Note: Map of Unit 6, San Francisco Subbasin (Map 7), follows.
    [GRAPHIC] [TIFF OMITTED] TP28OC10.006
    

[[Page 66535]]


    (13) Unit 7: Blue River Subbasin, Greenlee County, Arizona, and 
Catron County, New Mexico.
    (i) Blue River for approximately 81.4 km (50.6 mi) from the 
confluence with the San Francisco River at Township 2 South, Range 31 
East, southeast quarter of section 31 upstream to the confluence of 
Campbell Blue and Dry Blue creeks at Township 7 South, Range 21 West, 
southeast quarter of section 6.
    (ii) Campbell Blue Creek for approximately 12.4 km (7.7 mi) from 
the confluence of Dry Blue and Campbell Blue Creeks at Township 7 
South, Range 21 West, southeast quarter of section 6 to the confluence 
with Coleman Canyon in Township 4.5 North, Range 31 East, southwest 
quarter of the northeast quarter of section 32.
    (iii) Little Blue Creek for approximately 5.1 km (3.1 mi) from the 
confluence with the Blue River at Township 1 South, Range 31 East, 
center of section 5 upstream to the mouth of a canyon at Township 1 
North, Range 31 East, northeast quarter of section 29.
    (iv) Pace Creek for approximately 1.2 km (0.8 mi) from the 
confluence with Dry Blue Creek at Township 6 South, Range 21 West, 
southwest quarter of section 28 upstream to a barrier falls at Township 
6 South, Range 21 West, northeast quarter of section 29.
    (v) Frieborn Creek for approximately 1.8 km (1.1 mi) from the 
confluence with Dry Blue Creek at Township 7 South, Range 21 West, 
southwest quarter of the northwest quarter of section 5 upstream to an 
unnamed tributary flowing from the south in Township 7 South, Range 21 
West, northeast quarter of the southwest quarter of section 8.
    (vi) Dry Blue Creek for approximately 4.7 km (3.0 mi) from the 
confluence with Campbell Blue Creek at Township 7 South, Range 21 West, 
southeast quarter of Section 6 upstream to the confluence with Pace 
Creek in Township 6 South, Range 21 West, southwest quarter of section 
28.
    (vii) Note: Map of Unit 7, Blue River Subbasin (Map 8), follows.

[[Page 66536]]

[GRAPHIC] [TIFF OMITTED] TP28OC10.007

    (14) Unit 8: Gila River Subbasin, Catron, Grant, and Hidalgo 
Counties, New Mexico.
    (i) Gila River for approximately 165.1 km (102.6 mi) from the 
confluence with Moore Canyon at Township 18 South, Range 21 West, 
southeast quarter of the southwest quarter of section 32 upstream to 
the confluence of the East and West Forks of the Gila River at Township 
13 South, Range 13 West, center of section 8.
    (ii) West Fork Gila River for approximately 13.0 km (8.1mi) from 
the confluence with the East Fork Gila River at Township 13 South, 
Range 13 West, center of Section 8 upstream to the confluence with EE 
Canyon at Township 12 South, Range 14 West, east boundary of Section 
21.
    (iii) Middle Fork Gila River for approximately 19.1 km (11.9 mi) of 
the Middle Fork Gila River extending from the confluence with West Fork 
Gila

[[Page 66537]]

River at Township 12 South, Range 14 West, southwest quarter of section 
25 upstream to the confluence of Brothers West Canyon in Township 11 
South, Range 14 West, northeast quarter of section 33.
    (iv) East Fork Gila River for approximately 42.1 km (26.2 mi) 
extending from the confluence with West Fork Gila River at Township 13 
South, Range 13 West, center of section 8 upstream to the confluence of 
Beaver and Taylor Creeks in Township 11 South, Range 12 West, northeast 
quarter of section 17.
    (v) Mangas Creek for approximately 9.1 km (5.7 mi) extending from 
the confluence with the Gila River at Township 17 South, Range 16 West, 
southwest quarter of Section 5 upstream to the confluence with 
Blacksmith Canyon at Township 17 South, Range 17 West, northwest 
quarter of section 3.
    (vi) Note: Map of Unit 8, Gila River Subbasin (Map 9), follows.

[[Page 66538]]

[GRAPHIC] [TIFF OMITTED] TP28OC10.008

* * * * *
Spikedace (Meda fulgida)
    (1) Critical habitat units are depicted for Cochise, Gila, Graham, 
Greenlee, Pinal, and Yavapai Counties, Arizona, and for Catron, Grant, 
and Hidalgo Counties, New Mexico, on the maps below.
    (2) The physical and biological features of critical habitat for 
the spikedace are:
    (i) Habitat to support all egg, larval, juvenile, and adult 
spikedace. This habitat includes streams with perennial flows with a 
stream depth generally less than 1 m (3.3 ft), and with slow to swift 
flow velocities between 5 and 80 cm per second (1.9 and 31.5 in. per 
second). Appropriate stream microhabitat types include glides, runs, 
riffles, the margins of pools, and eddies, and backwater components 
over sand, gravel, and

[[Page 66539]]

cobble substrates with low or moderate amounts of fine sediment and 
substrate embeddedness. Appropriate habitat will have a low gradient of 
less than approximately 1.0 percent, at elevations below 2,100 m (6,890 
ft). Water temperatures should be in the general range of 8.0 to 28.0 
[deg]C (46.4 to 82.4 [deg]F).
    (ii) An abundant aquatic insect food base consisting of mayflies, 
true flies, black flies, caddisflies, stoneflies, and dragonflies.
    (iii) Streams with no or no more than low levels of pollutants.
    (iv) Perennial flows, or interrupted stream courses that are 
periodically dewatered but that serve as connective corridors between 
occupied or seasonally occupied habitat and through which the species 
may move when the habitat is wetted.
    (v) No nonnative aquatic species, or levels of nonnative aquatic 
species that are sufficiently low as to allow persistence of spikedace.
    (vi) Streams with a natural, unregulated flow regime that allow for 
periodic flooding or, if flows are modified or regulated, a flow regime 
that allows for adequate river functions, such as flows capable of 
transporting sediments.
    (3) We have determined that all designated areas contain at least 
one PBF for spikedace. There are no developed areas within the 
designation except for manmade barriers constructed on streams, low 
water road crossings of streams, and areas beneath bridges, all of 
which do not remove the suitability of these areas for this species. 
Where a manmade structure is within the proposed critical habitat 
designation, the structure would be considered to be proposed critical 
habitat if it continues to contain one or more of the PBFs. If the 
structure does not contain one or more of the PBFs, the structure is 
excluded by text in this proposed rule. For excluded structures, a 
Federal action involving these lands (if and when designated) would not 
trigger section 7 consultation with respect to critical habitat and the 
prohibition of destruction or adverse modification, unless the specific 
action may affect adjacent critical habitat.
    (4) Each stream segment includes a lateral component that consists 
of 300 feet (91.4 meters) on either side of the stream channel measured 
from the stream edge at bank full discharge. This lateral component of 
critical habitat contains and contributes to the physical and 
biological features essential to the spikedace and is intended as a 
surrogate for the 100-year floodplain.
    (5) Critical habitat map units. Data layers defining map units were 
created on a base of USGS 7.5' quadrangles along with shapefiles 
generated by the Arizona Land Resource Information Service for land 
ownership, streams, counties, and the Public Land Survey System. 
Information on species locations was derived from databases developed 
by the Arizona Game and Fish Department, the New Mexico Department of 
Game and Fish, and Arizona State University.
    (6) Note: Index map for spikedace critical habitat units follows.

[[Page 66540]]

[GRAPHIC] [TIFF OMITTED] TP28OC10.009

    (7) Unit 1: Verde River Subbasin, Yavapai County, Arizona.
    (i) Verde River for approximately 171.8 km (106.7 mi), extending 
from the confluence with Fossil Creek in Township 11 North, Range 6 
East, northeast quarter of section 25 upstream to Sullivan Dam in 
Township 17 North, Range 2 West, northwest quarter of section 15.
    (ii) Granite Creek for approximately 3.2 km (2.0 mi), extending 
from the confluence with the Verde River in Township 17 North, Range 2 
West, northeast quarter section 14 upstream to a spring in Township 17 
North, Range 2 West, southwest quarter of the southwest quarter of 
section 13.
    (iii) Oak Creek for approximately 54.3 km (33.7 mi), extending from 
the confluence with the Verde River in Township 15 North, Range 4 East, 
southeast quarter section 20 upstream to the confluence with an unnamed

[[Page 66541]]

tributary from the south in Township 17 North, Range 5 East, southeast 
quarter of the northeast quarter of section 24.
    (iv) Beaver Creek/Wet Beaver Creek for approximately 33.5 km (20.8 
mi), extending from the confluence with the Verde River in Township 14 
North, Range 5 East, southeast quarter of section 30 upstream to the 
confluence with Casner Canyon in Township 15 North, Range 6 East, 
northwest quarter of section 23.
    (v) West Clear Creek for approximately 10.9 km (6.8. mi), extending 
from the confluence with the Verde River in Township 13 North, Range 5 
East, center section 21, upstream to the confluence with Black Mountain 
Canyon in Township 13 North, Range 6 East, southeast quarter of section 
17.
    (vi) Fossil Creek for approximately 7.5 km (4.7 mi) extending from 
the confluence with the Verde River in Township 11 North, Range 5 East, 
northeast quarter of section 25 upstream to the confluence with an 
unnamed tributary from the northwest in Township 11.5 North, Range 7 
East, center of section 29.
    (vii) Note: Map of Unit 1, Verde River Subbasin (Map 2), follows.

[[Page 66542]]

[GRAPHIC] [TIFF OMITTED] TP28OC10.010

    (8) Unit 2: Salt River Subbasin, Gila County, Arizona.
    (i) Tonto Creek for approximately 47.8 km (29.7 mi) extending from 
the confluence with Greenback Creek in Township 5 North, Range 11 East, 
northwest quarter of section 8 upstream to the confluence with Houston 
Creek in Township 9 North, Range 11 East, northeast quarter of section 
18.
    (ii) Greenback Creek for approximately 15.1 km (9.4 mi) from the 
confluence with Tonto Creek in Township 5 North, Range 11 East, 
northwest quarter of section 8 upstream to Lime Springs in Township 6 
North, Range 12 East, southwest quarter of section 20.
    (iii) Rye Creek for approximately 2.8 km (1.8 mi) extending from 
the confluence with Tonto Creek in Township 8 North, Range 10 East, 
northeast quarter of section 24 upstream to the confluence with Brady 
Canyon in

[[Page 66543]]

Township 8 North, Range 10 East, northwest quarter of section 14.
    (iv) Spring Creek for approximately 27.2 km (16.9 mi) extending 
from the confluence with the Tonto River at Township 10 North, Range 11 
East, southeast quarter of section 36 upstream to the confluence with 
Sevenmile Canyon at Township 8 North, Range 13 East, northern boundary 
of section 20.
    (v) Rock Creek for approximately 5.8 km (3.6 mi) extending from the 
confluence with Spring Creek at Township 8 North, Range 12 East, 
southeast quarter of section 1 upstream to the confluence with Buzzard 
Roost Canyon at Township 8 North, 12 East, center of section 24.
    (vi) Note: Map of Unit 2, Salt River Subbasin (Map 3), follows.
    [GRAPHIC] [TIFF OMITTED] TP28OC10.011
    

[[Page 66544]]


    (9) Unit 3: San Pedro River Subbasin, Cochise, Graham, Pima and 
Pinal Counties, Arizona.
    (i) San Pedro River for approximately 60.0 km (37.2 mi) extending 
from the International Boundary with Mexico in Township 24 South, Range 
22 East, Section 19 downstream to the confluence with the Babocomari 
River in the San Juan de las Boquillas y Nogales land grant.
    (ii) Aravaipa Creek for approximately 44.9 km (27.9 mi) extending 
from the confluence with the San Pedro River in Township 7 South, Range 
16 East, center of section 9 upstream to the confluence with Stowe 
Gulch in Township 6 South, Range 19 East, southeast quarter of the 
northeast quarter of section 35.
    (iii) Deer Creek--3.7 km (2.3 mi) of the creek extending from the 
confluence with Aravaipa Creek at Township 6 South, Range 18 East, 
section 14 upstream to the boundary of the Aravaipa Wilderness at 
Township 6 South, Range 19 East, section 18.
    (iv) Turkey Creek--4.3 km (2.7 mi) of the creek extending from the 
confluence with Aravaipa Creek at Township 6 South, Range 19 East, 
section 19 upstream to the confluence with Oak Grove Canyon at Township 
6 South, Range 19 east, section 32.
    (v) Hot Springs Canyon for approximately 19.0 km (11.8 mi) 
extending from the confluence with the San Pedro River in Township 13 
South, Range 19 East, center of section 23 upstream to the confluence 
with Bass Canyon in Township 12 South, Range 20 East, northeast quarter 
of section 36.
    (vi) Redfield Canyon for approximately 22.5 km (14.0 mi) extending 
from the confluence with the San Pedro River in Township 11 South, 
Range 18 East, southwest quarter of section 34 upstream to the 
confluence with Sycamore Canyon in Township 11 South, Range 20 East, 
northwest quarter of section 28.
    (vii) Bass Canyon for approximately 5.5 km (3.4 mi) from the 
confluence with Hot Springs Canyon in Township 12 South, Range 20 East, 
northeast quarter of section 36 upstream to the confluence with Pine 
Canyon in Township 12 South, Range 21 East, center of section 20.
    (viii) Note: Map of Unit 3, San Pedro River Subbasin (Map 4), 
follows.

[[Page 66545]]

[GRAPHIC] [TIFF OMITTED] TP28OC10.012

    (10) Unit 4: Bonita Creek Subbasin, Graham County, Arizona.
    (i) Bonita Creek for approximately 23.8 km (14.8 mi) from the 
confluence with the Gila River in Township 6 South, Range 28 East, 
southeast quarter of section 21 upstream to the confluence with 
Martinez Wash in Township 4 South, Range 27 East, southeast quarter of 
Section 27.
    (ii) Note: Map of Unit 4, Bonita Creek Subbasin (Map 5), follows.

[[Page 66546]]

[GRAPHIC] [TIFF OMITTED] TP28OC10.013

    (11) Unit 5: Eagle Creek Subbasin, Graham and Greenlee Counties, 
Arizona.
    (i) Eagle Creek for approximately 75 km (46.9 mi) from the Freeport 
McMoRan diversion dam at Township 4 South, Range 28 East, southwest 
quarter of section 23 upstream to the confluence of East Eagle Creek in 
Township 2 North, Range 28 East, southwest quarter of section 20.
    (ii) Note: Map of Unit 5, Eagle Creek Subbasin (Map 6), follows.

[[Page 66547]]

[GRAPHIC] [TIFF OMITTED] TP28OC10.014

    (12) Unit 6: San Francisco River Subbasin, Greenlee County, 
Arizona, and Catron County, New Mexico.
    (i) San Francisco River for approximately 181.0 km (112.3 mi) of 
the San Francisco River extending from the confluence with the Gila 
River in Township 5 South, Range 29 East, southeast quarter of section 
21 upstream to the confluence with the Tularosa River in Township 7 
South, Range 19 West, southwest quarter of section 23.
    (ii) Note: Map of Unit 6, San Francisco River Subbasin (Map 7), 
follows.

[[Page 66548]]

[GRAPHIC] [TIFF OMITTED] TP28OC10.015

    (13) Unit 7: Blue River Subbasin, Greenlee County, Arizona, and 
Catron County, New Mexico.
    (i) Blue River for approximately 81.4 km (50.6 mi) from the 
confluence with the San Francisco River at Township 2S., Range 31 East, 
southeast quarter of section 31 upstream to the confluence of Campbell 
Blue and Dry Blue Creeks at Township 7 South, Range 21 West, southeast 
quarter of section 6.
    (ii) Campbell Blue Creek for approximately 12.4 km (7.7 mi) from 
the confluence of Dry Blue and Campbell Blue Creeks at Township 7 
South, Range 21 West, southeast quarter of section 6 to the confluence 
with Coleman Canyon in Township 4.5 North, Range 31 East, southwest 
quarter of the northeast quarter of section 32.
    (iii) Little Blue Creek for approximately 5.1 km (3.1 mi) from the 
confluence with the Blue River at Township 1 South, Range 31 East,

[[Page 66549]]

center Section 5 upstream to the mouth of a canyon at Township 1 North, 
Range 31 East, northeast quarter of section 29.
    (iv) Pace Creek for approximately 1.2 km (0.8 mi) from the 
confluence with Dry Blue Creek at Township 6 South, Range 21 West, 
southwest quarter of Section 28 upstream to a barrier falls at Township 
6 South, Range 21 West, northeast quarter of section 29.
    (v) Frieborn Creek for approximately 1.8 km (1.1 mi) from the 
confluence with Dry Blue Creek at Township 7 South, Range 21 West, 
southwest quarter of the northwest quarter of section 5 upstream to an 
unnamed tributary flowing from the south in Township 7 South, Range 21 
West, northeast quarter of southwest quarter of section 8.
    (vi) Dry Blue Creek for approximately 4.7 km (3.0 mi) from the 
confluence with Campbell Blue Creek at Township 7 South, Range 21 West, 
southeast quarter of Section 6 upstream to the confluence with Pace 
Creek in Township 6 South, Range 21 West, southwest quarter of section 
28.
    (vii) Note: Map of Unit 7, Blue River Subbasin (Map 8), follows.

[[Page 66550]]

[GRAPHIC] [TIFF OMITTED] TP28OC10.016

    (14) Unit 8: Gila River Subbasin, Catron, Grant, and Hidalgo 
Counties, New Mexico.
    (i) Gila River for approximately 165.1 km (102.6 mi) from the 
confluence with Moore Canyon at Township 18 South, Range 21 West, 
southeast quarter of the southwest quarter of Section 32 upstream to 
the confluence of the East and West Forks of the Gila River at Township 
13 South, Range 13 West, center of Section 8.
    (ii) West Fork Gila River for approximately 13.0 km (8.1 mi) from 
the confluence with the East Fork Gila River at Township 13 South, 
Range 13 West, center of section 8 upstream to the confluence with EE 
Canyon at Township 12 South, Range 14 West, east boundary of Section 
21.
    (iii) Middle Fork Gila River for approximately 12.5 km (7.7 mi) of 
the Middle Fork Gila River extending from the confluence with West Fork 
Gila

[[Page 66551]]

River at Township 12 South, Range 14 West, southwest quarter of section 
25 upstream to the confluence of Big Bear Canyon in Township 12 South, 
Range 14 West, southwest quarter of section 2.
    (iv) East Fork Gila River for approximately 42.1 km (26.2 mi) 
extending from the confluence with West Fork Gila River at Township 13 
South, Range 13 West, center of Section 8 upstream to the confluence of 
Beaver and Taylor Creeks in Township 11 South, Range 12 West, northeast 
quarter of section 17.
    (v) Mangas Creek for approximately 9.1 km (5.7 mi) extending from 
the confluence with the Gila River at Township 17 South, Range 16 West, 
southwest quarter of section 5 upstream to the confluence with 
Blacksmith Canyon at Township 17 South, Range 17 West, northwest 
quarter of section 3.
    (vi) Note: Map of Unit 8, Gila River Subbasin (Map 9), follows.
    [GRAPHIC] [TIFF OMITTED] TP28OC10.017
    

[[Page 66552]]



Authority

    The authority for this section is section 4 of the Endangered 
Species Act of 1973, as amended (16 U.S.C. 1531 et seq.).

    Dated: October 13, 2010.
Thomas L. Strickland,
Assistant Secretary for Fish and Wildlife and Parks.
[FR Doc. 2010-26477 Filed 10-27-10; 8:45 am]
BILLING CODE 4310-55-C