[Federal Register Volume 75, Number 119 (Tuesday, June 22, 2010)]
[Proposed Rules]
[Pages 35375-35397]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2010-15067]


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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

[Docket No. FWS-R2-ES-2009-0014]
[92210-1117-0000-B4]
RIN 1018-AW50


Endangered and Threatened Wildlife and Plants; Designation of 
Critical Habitat for Roswell Springsnail, Koster's Springsnail, Noel's 
Amphipod, and Pecos Assiminea

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Proposed rule.

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SUMMARY: We, the U.S. Fish and Wildlife Service, propose to revise 
designated critical habitat for the Pecos assiminea (Assiminea pecos), 
and to newly designate critical habitat for the Roswell springsnail 
(Pyrgulopsis roswellensis), Koster's springsnail (Juturnia kosteri), 
and Noel's amphipod (Gammarus desperatus), under the Endangered Species 
Act of 1973, as amended. In total, we are proposing to designate as 
critical habitat approximately 515 acres (208.4 hectares) for the four 
species. The proposed critical habitat is located in Chaves County, New 
Mexico, and Pecos and Reeves Counties, Texas. We also announce the 
availability of the draft economic analysis and draft environmental 
assessment for this action.

DATES: We request that comments be received or postmarked on or before 
August 23, 2010. Please note that submissions via the Federal 
eRulemaking Portal (see ADDRESSES section, below) must be made by 11:59 
pm Eastern Standard Time on this date. We must receive requests for 
public hearings, in writing, at the address shown in the FOR FURTHER 
INFORMATION CONTACT section by August 6, 2010.

ADDRESSES: You may submit comments by one of the following methods:
     Federal eRulemaking Portal: http://www.regulations.gov. 
Search for docket number FWS-R2-ES-2009-0014 and then follow the 
instructions for submitting comments.
     U.S. mail or hand-delivery: Public Comments Processing, 
Attn: Docket No. FWS-R2-ES-2009-0014; Division of Policy and Directives 
Management; U.S. Fish and Wildlife Service; 4401 N. Fairfax Drive, 
Suite 222; Arlington, VA 22203.
    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: Wally ``J'' Murphy, Field Supervisor, 
U.S. Fish and Wildlife Service, New Mexico Ecological Services Field 
Office, 2105 Osuna Rd NE, Albuquerque, NM 87113; telephone 505-761-
4781; facsimile 505-246-2542. 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

    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 other interested parties concerning 
the proposed revisions to critical habitat for the Pecos assiminea 
(Assiminea pecos), and the proposed critical habitat for the Roswell 
springsnail (Pyrgulopsis roswellensis), Koster's springsnail (Juturnia 
kosteri), and Noel's amphipod (Gammarus desperatus), as well as the 
draft economic analysis and draft environmental assessment of the 
proposed designation. We will consider information and recommendations 
from all interested parties. We particularly seek comments concerning:
    (1) 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 is not prudent.
    (2) Specific information on:
     The amount and distribution of habitat for the Roswell 
springsnail,

[[Page 35376]]

Koster's springsnail, Noel's amphipod, and Pecos assiminea (four 
invertebrates);
     What areas occupied at the time of listing and that 
contain features essential to the conservation of the species we should 
include in the designation and why;
     Special management considerations or protections that the 
features essential to the conservation of the Roswell springsnail, 
Koster's springsnail, Noel's amphipod, and Pecos assiminea that have 
been 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.
    (3) Land use management and current or planned activities in the 
subject areas and their possible impacts on proposed critical habitat.
    (4) Any probable economic, national security, or other relevant 
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.
    (5) Information on whether the draft economic analysis identifies 
all local costs attributable to the proposed critical habitat 
designation and information on any costs that have been inadvertently 
overlooked.
    (6) Whether the draft economic analysis correctly assesses the 
effect on regional costs associated with any land use controls that may 
derive from the designation of critical habitat.
    (7) Whether the draft economic analysis or draft environmental 
assessment makes appropriate assumptions regarding current practices 
and likely regulatory changes imposed as a result of the designation of 
critical habitat.
    (8) Whether the draft economic analysis and draft environmental 
assessment appropriately identify all costs and benefits that could 
result from the designation.
    (9) Economic data on the incremental effects that would result from 
designating any particular area as critical habitat.
    (10) 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.
    To ensure that any final action resulting from this proposed rule 
will be as accurate and as effective as possible, we request that you 
send relevant information for our consideration. The comments that will 
be most useful and likely to influence our decisions are those that you 
support by quantitative information or studies and those that include 
citations to, and analyses of, the applicable laws and regulations. 
Please make your comments as specific as possible and explain the bases 
for them. In addition, please include sufficient information with your 
comments to allow us to authenticate any scientific or commercial data 
you include.
    You must submit your comments and materials concerning this 
proposed rule, the associated draft economic analysis, and the 
associated draft environmental assessment by one of the methods listed 
above in the ADDRESSES section. We will not accept comments sent by e-
mail or fax or to an address not listed in ADDRESSES.
    If you submit a comment via http://www.regulations.gov, your entire 
comment--including any personal identifying information, such as your 
address, telephone number, or e-mail address--will be posted on the Web 
site. Please note that comments submitted to this Web site are not 
immediately viewable. When you submit a comment, the system receives it 
immediately. However, the comment will not be publicly viewable until 
we post it, which might not occur until several days after submission.
    If you mail or hand-carry a hardcopy comment directly to us that 
includes personal information, 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. To ensure that the 
electronic docket for this rulemaking is complete and all comments we 
receive are publicly available, we will post all hardcopy comments on 
http://www.regulations.gov.
    In addition, comments and materials we receive, as well as 
supporting documentation used in preparing this proposed rule, will be 
available for public inspection in two ways:
    (1) You can view them on http://www.regulations.gov. Search for 
docket number FWS-R2-ES-2009-0014.
    (2) You can make an appointment, during normal business hours, to 
view the comments and materials in person at he U.S. Fish and Wildlife 
Service, New Mexico Ecological Services Field Office (see FOR FURTHER 
INFORMATION CONTACT).
    You may obtain copies of the original proposed rule, the draft 
economic analysis, and the draft environmental assessment online at 
http://www.regulations.gov, by mail from the New Mexico Ecological 
Services Field Office (see FOR FURTHER INFORMATION CONTACT), or by 
visiting our website at http://www.fws.gov/southwest/es/NewMexico/.

Public Availability of Comments

    As stated above in more detail, before including your address, 
phone number, e-mail address, or other personal identifying information 
in your comment, you should be aware that your entire comment--
including your personal identifying information--may be made publicly 
available at any time. While you can ask us in your comment to withhold 
your personal identifying information from public review, we cannot 
guarantee that we will be able to do so.

Background

    It is our intent to discuss only those topics relevant to the 
designation of critical habitat in this proposed rule. For more 
information on the Roswell springsnail (Pyrgulopsis roswellensis), 
Koster's springsnail (Juturnia kosteri), Noel's amphipod (Gammarus 
desperatus), and Pecos assiminea (Assiminea pecos), refer to the final 
listing rule published in the Federal Register on August 9, 2005 (70 FR 
46304), and to the document announcing the reopening of the comment 
period on the proposed designation of lands of the Bitter Lake National 
Wildlife Refuge as critical habitat for these species that published on 
March 12, 2009 (74 FR 10701).
    All four invertebrate species are associated with aquifer-fed 
spring systems in desert grasslands of the Pecos River Basin in 
southeast New Mexico and southwest Texas. This basin has abundant 
``karst'' topography (landscape created by groundwater dissolving 
sedimentary rock), such as sinkholes, caverns, springs, and underground 
springs, which have created unique settings harboring diverse 
assemblages of plants and animals. The isolated limestone and gypsum 
springs, seeps, and wetlands located in and around Roswell, New Mexico, 
and Pecos and Reeves Counties, Texas, provide the last known habitats 
in the world for several endemic (native) species of fish, plants, 
mollusks, and crustaceans, including the Roswell springsnail and 
Koster's springsnail of the freshwater snail family Hydrobiidae, Pecos 
assiminea of the snail family Assimineidae, and Noel's amphipod (a 
crustacean of the family Gammaridae) (New Mexico Department of Game and 
Fish (NMDGF) 2005, pp. 9-12) .
    The Roswell springsnail and Koster's springsnail are aquatic 
species,

[[Page 35377]]

distributed in geographically separate populations in isolated 
limestone and gypsum springs, seeps, and wetlands. As with other snails 
in the family Hydrobiidae, the Roswell springsnail and Koster's 
springsnail are completely aquatic but can survive in seepage areas, as 
long as flows are perennial and within the species' physiological 
tolerance limits (NMDGF 2005, p. 9). The Roswell springsnail and 
Koster's springsnail are currently known only from the Middle Tract of 
Bitter Lake National Wildlife Refuge (Refuge) and a nearby complex of 
springs owned by the city of Roswell, Chaves County, New Mexico. The 
core population of Roswell springsnail is in the Sago Springs Complex 
and Bitter Creek on the Refuge. The Sago Springs Complex is 
approximately 1,000 feet (ft) (304 meters (m)) long, half of which 
flows underground with aboveground flow in the upper reaches restricted 
to sinkholes. Bitter Creek is six times longer than the Sago Springs 
Complex and has a total length of 1.1 miles (mi) (1.8 kilometers (km)). 
Roswell springsnail formerly occurred on private land at North Spring 
east of Roswell but has since been extirpated (NMDGF 2005, p. 12).
    Koster's springsnail is most abundant in the deep organic 
substrates (material on the bottom of the stream) of Bitter Creek and 
its headwaters (Lang 1999, p. B36; NMDGF 2005, p. 13) on the Refuge; it 
also occurs at the Sago Springs Complex, but in lower numbers, as well 
as in Lake St. Francis, in the southwestern corner of Impoundment 15, 
in Hunter Marsh, in the spring-ditches of Impoundments 6 and 7, and in 
several springs adjacent to the Refuge owned by the city of Roswell 
(NMDGF 2005, p. 13; Sanchez 2009, p. 1; B. Lang, NMDGF, pers. comm. 
2010) The species has not been found in recent times along the western 
boundary of the spring run originating from the saline waters of Bitter 
Lake, bordering Impoundment 3 on the Refuge (NMDGF 2005, p. 12), and it 
was recently extirpated from North Spring (NMDGF 2005, p. 11). Fossil 
records indicate that at least one or more of these snail species was 
historically found at Berrendo Spring, North Spring, and South Spring 
River,, and along the Pecos River (NMDGF 1999, pp. A1, A3, A8, A11). 
This evidence suggests an apparent historical decline in the numbers, 
range, and distribution of these species.
    The Pecos assiminea is a minute marsh snail that seldom occurs 
immersed in water but prefers a humid microhabitat created by wet mud 
or beneath vegetation mats, typically within about 1 inch (in) (2 to 3 
centimeters (cm)) of running water. Pecos assiminea is presently known 
from two sites at the Refuge, from a large population at Diamond Y 
Spring and its associated drainage in Pecos County, Texas, and at East 
Sandia Spring, in Reeves County, Texas. On the Refuge, Pecos assiminea 
occurs sporadically in Bitter Creek, in a dense population around the 
perimeter of a sinkhole within the Sago Springs Complex, on the western 
perimeter of Impoundment 7, and in the extreme southwest corner of 
Impoundment 15 (NMDGF 2005, p. 10). Critical habitat is currently 
designated for the Pecos assiminea at the Texas sites.
    Noel's amphipod is a small, freshwater shrimp in the family 
Gammaridae that inhabits shallow, cool, well-oxygenated waters of 
streams, ponds, ditches, sloughs, and springs (Holsinger 1976, p. 28; 
Pennak 1989, p. 478). Noel's amphipod is currently known from the 
following five sites at the Refuge: Sago Springs Complex, Bitter Creek 
and its headwater springs, Unit 6 spring-ditch, Unit 7 spring-ditch, 
and Hunter Marsh (NMDGF 2005, p. 9; Sanchez 2009, p. 1). It is also 
found in several springs just outside the Refuge boundary on property 
owned by the City of Roswell (G. Warrick, pers. comm., 2005). The 
species was extirpated from Lander Springbrook between 1951 and 1960, 
and the North Spring population was lost between 1978 and 1988 (NMDGF 
2005, p. 9). The extirpations were attributed to regional groundwater 
depletions and habitat alterations (spring channelization), 
respectively (Cole 1985, p. 94).

Previous Federal Actions

    On August 9, 2005, we listed Roswell springsnail (Pyrgulopsis 
roswellensis), Koster's springsnail (Juturnia kosteri), Noel's amphipod 
(Gammarus desperatus), and Pecos assiminea (Assiminea pecos) as 
endangered under the Act (70 FR 46304). In that rule, we also 
designated critical habitat for Pecos assiminea at Diamond Y Springs 
Complex in Pecos County, Texas, and at East Sandia Springs in Reeves 
County, Texas. We excluded Bitter Lake National Wildlife Refuge from 
the critical habitat designation because special management for the 
four invertebrates was already occurring on the Refuge.
    On March 12, 2009, in response to a complaint filed by Forest 
Guardians (now WildEarth Guardians) challenging the exclusion of the 
Refuge from the final critical habitat designation for the four 
species, we published a document announcing the reopening of the 
comment period on the proposed designation of lands of the Bitter Lake 
National Wildlife Refuge as critical habitat for the four invertebrates 
(74 FR 10701).

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 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, 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 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 by non-Federal landowners. 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

[[Page 35378]]

destruction or adverse modification finding, the Federal action 
agency's and the applicant's obligation 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 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 
physical and biological features 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 we are determining which areas should be designated as 
critical habitat, our primary source of information is generally the 
information 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 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 these planning efforts 
calls for a different outcome.

Primary Constituent Elements

    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 that 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 consider the physical or biological features essential to the 
conservation of the species to be the primary constituent elements 
(PCEs) laid out in the appropriate quantity and spatial arrangement for 
the conservation of the species. We derived the specific PCEs from the 
biological needs of the Roswell springsnail, Koster's springsnail, 
Noel's amphipod, and Pecos assiminea. We determined the PCEs for the 
four invertebrates from data and studies on their general habitat and 
life history requirements including, but not limited to: Noel 1954, pp. 
120-135; Cole 1981, pp. 27-32; Taylor 1987, pp. 1-46; Pennak 1978, pp. 
451-463; Pennak 1989, pp. 474-488; NMDGF 1999, p. A1-B46; and NMDGF 
2005, pp. 1-80. A description of the essential environment as it 
relates to the specific PCEs required of the four invertebrates is 
described below.

Space for Individual and Population Growth and for Normal Behavior

Roswell springsnail, Koster's springsnail, Noel's amphipod
    The aquatic environment provides foraging and sheltering habitat 
for Roswell springsnail, Koster's springsnail, and Noel's amphipod, as 
well as habitat structure necessary for reproduction and survival of 
offspring. These invertebrates are completely aquatic and require 
perennial, flowing water for all of their life stages. The springsnails 
can survive in seepage areas, as long as flows are perennial and within 
the species' physiological tolerance limit; pool-like habitat is less 
suitable for these species, which prefer flowing water. They inhabit 
springs and spring-fed wetland systems with variable water temperatures 
(10-20 degrees Celsius (\o\C) (50-68 degrees Fahrenheit (\o\F)). In 
general, the springsnails inhabit slow to moderate water velocities 
over compact substrate ranging from deep organic silts to gypsum sands 
and gravel (NMDGF 2005, pp. 13, 16). Habitat of Koster's springsnail 
consists of soft substrates of springs and seeps (Taylor 1987, p. 43). 
Roswell springsnail, on the other hand, was found to be most abundant 
on hard, gypsum substrate (NMDGF 2005, p. 16), which may make the 
species more susceptible to sedimentation. Noel's amphipod is found 
beneath stones and in aquatic vegetation (Cole 1988, p. 5; Smith 2001, 
pp. 572-574). The addition of stones, which increased current velocity, 
appeared to improve habitat for Noel's amphipod along Unit 6 spring-
ditch on the Refuge (Lang 2002, p. 2).

[[Page 35379]]

    The two springsnails and Noel's amphipod are sensitive to water 
contamination. Amphipods generally do not tolerate habitat desiccation 
(drying), standing water, sedimentation, or other adverse environmental 
conditions; they are very sensitive to habitat degradation (NMDGF 2000, 
p. B3; Smith 2001, p. 575; NMDGF 2005, p. 15). Further, Taylor (1985, 
p. 15) concluded that an unidentified groundwater pollutant was 
responsible for reduction in abundance of springsnail species in the 
headspring and outflow of Diamond Y Spring, in Pecos County, Texas.
Pecos assiminea
    The Pecos assiminea requires saturated, moist soil at stream or 
spring-run margins and is found in wet mud or beneath mats of 
vegetation, usually within 1 in (2 to 3 cm) of flowing water. Spring 
complexes that contain flowing water create saturated soils that 
provide the specific habitat needed for population growth, sheltering, 
and normal behavior of the species. Although this snail seldom occurs 
immersed in water, the species cannot withstand permanent drying of 
springs or spring complexes. Consequently, wetland plant species are 
required to provide leaf litter (dead leaf material), shade, and 
appropriate microhabitat. Plant species such as American three-square 
(Scirpus americanus), spike rush (Eleocharis spp.), inland saltgrass 
(Distichlis spicata), and rushes (Juncus spp.) provide the appropriate 
cover and shelter required by Pecos assiminea (NMDGF 2005, p. 13).

Food

    Invertebrates in small spring ecosystems depend on food from two 
sources: that which grows in or on the substrate (aquatic and attached 
plants and algae) and that which falls or is blown into the system 
(primarily leaves). Leaves from nonnative plants that fall into the 
water are often less suitable food sources for invertebrates because of 
either their resins or their physical structure (Bailey et al. 2001, p. 
445). Water is also the medium necessary to provide the algae, detritus 
(dead or partially decayed plant materials or animals), bacteria, and 
submergent vegetation on which all four species depend as a food 
resource.
Roswell springsnail and Koster's springsnail
    The springsnails feed on algae, bacteria, and decaying organic 
material (NMDGF 2005, p. 14). They will also incidentally ingest small 
invertebrates while grazing on algae and detritus. Submergent 
vegetation contributes the necessary nutrients, detritus, and bacteria 
on which these species forage. Resource abundance and productivity 
appears to be an important factor in regulating population size (NMDGF 
2005, p. 16).
Noel's amphipod
    Amphipods are omnivorous, feeding on algae, submergent vegetation, 
and decaying organic matter (Holsinger 1976, p. 28; Pennak 1989, p. 
476). Noel's amphipod is often found in beds of submerged aquatic 
plants, indicating that they probably feed on a surface film of algae, 
diatoms, bacteria, and fungi (Smith 2001, p. 575; NMDGF 2005, p. 14). 
Young amphipods depend on microbial foods, such as algae and bacteria, 
associated with aquatic plants (Covich and Thorp 1991, p. 677). 
Cannibalism may occur at high densities when food becomes limiting 
(Smith 2001, p. 575; NMDGF 2005, p. 15).
Pecos assiminea
    The Pecos assiminea has a file-like radula (a ribbon of teeth) 
situated behind the mouth that it uses to graze or scrape food from the 
foraging surface. Saturated soils and wetland vegetation adjacent to 
spring complexes contribute to the necessary components to support the 
algae, detritus, and bacteria on which this species forages.

Summary of Primary Constituent Elements

Roswell springsnail and Koster's springsnail
    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 the primary constituent element 
essential to the conservation of Roswell springsnail and Koster's 
springsnail is springs and spring-fed wetland systems that:
    (1) Have permanent, flowing, unpolluted water;
    (2) Have slow to moderate water velocities;
    (3) Have substrates ranging from deep organic silts to limestone 
cobble and gypsum;
    (4) Have stable water levels with natural diurnal (daily) and 
seasonal variations;
    (5) Consist of fresh to moderately saline water;
    (6) Vary in temperature between 10-20 \o\C (50-68 \o\F) with 
natural seasonal and diurnal variations slightly above and below that 
range; and
    (7) Provide abundant food, consisting of:
    (a) Algae, bacteria, and decaying organic material; and
    (b) Submergent vegetation that contributes the necessary nutrients, 
detritus, and bacteria on which these species forage.
Noel's amphipod
    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 the primary constituent element 
essential to the conservation of Noel's amphipod is springs and spring-
fed wetland systems that:
    (1) Have permanent, flowing, unpolluted water;
    (2) Have slow to moderate water velocities;
    (3) Have substrates including limestone cobble and aquatic 
vegetation;
    (4) Have stable water levels with natural diurnal (daily) and 
seasonal variations;
    (5) Consist of fresh to moderately saline water;
    (6) Have minimal sedimentation;
    (7) Vary in temperature between 10-20 \o\C (50-68 \o\F) with 
natural seasonal and diurnal variations slightly above and below that 
range; and
    (8) Provide abundant food, consisting of:
    (a) Submergent vegetation and decaying organic matter;
    (b) A surface film of algae, diatoms, bacteria, and fungi; and
    (c) Microbial foods, such as algae and bacteria, associated with 
aquatic plants algae, bacteria, and decaying organic material.
Pecos assiminea
    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 the primary constituent element 
essential to the conservation of Pecos assiminea is moist or saturated 
soil at stream or spring run margins:
    (1) With native vegetation growing in or adapted to aquatic or very 
wet environment, such as salt grass or sedges;
    (2) That consists of wet mud or occurs beneath mats of vegetation;
    (3) That is within 1 inch (2 to 3 centimeters) of flowing water;
    (4) That has native wetland plant species that provide leaf litter, 
shade, cover, and appropriate microhabitat;
    (5) That contains wetland vegetation adjacent to spring complexes 
that

[[Page 35380]]

supports the algae, detritus, and bacteria needed for foraging;
    (6) That has adjacent spring complexes with:
    (a) Permanent, flowing, unpolluted, fresh to moderately saline 
water; and
    (b) Stable water levels with natural diurnal and seasonal 
variations.

Special Management Considerations or Protection

    When designating critical habitat, we assess whether the specific 
areas within the geographical area occupied by the species at the time 
of listing contain features that are essential to the conservation of 
the species and that may require special management considerations or 
protection. As stated in the final listing rule (70 FR 46304, August 9, 
2005), threats to the four invertebrates include reducing or 
eliminating water in suitable or occupied habitat through drought or 
pumping; introducing pollutants to levels unsuitable for the species 
from urban areas, agriculture, release of chemicals, and oil and gas 
operations; fires that reduce or eliminate available habitat; and 
introducing nonnative species into the invertebrates' inhabited spring 
systems such that suitable habitat is reduced or eliminated. Each of 
these threats is discussed below.
Water Quantity
    These four species depend on water for survival. Therefore, the 
loss or alteration of spring habitat continues to be the main threat to 
the four invertebrates. The scattered distribution of springs makes 
them aquatic islands of unique habitat in an arid-land matrix (Myers 
and Resh 1999, p. 815). Members of the snail family Hydrobiidae 
(including Roswell and Koster's springsnails) are susceptible to 
extirpation or extinction because they often occur in isolated desert 
springs (Hershler 1989, p. 294; Hershler and Pratt 1990, p. 291; 
Hershler 1994, p. 1; Lydeard et al. 2004, p. 326). There is evidence 
these habitats have been historically reduced or eliminated by aquifer 
depletion (Jones and Balleau 1996, p. 4). The lowering of water tables 
through aquifer withdrawals for irrigation and municipal use has 
degraded desert spring habitats. At least two historic sites for the 
invertebrates (South Spring, Lander Spring) are currently dry due to 
aquifer depletion (Cole 1981, p. 27; Jones and Balleau 1996, p. 5), and 
Berrendo Spring, historical habitat for the Roswell springsnail, is 
currently at 12 percent of the original 1880s flow. However, during the 
mid-1970s, the areas proposed in this document as critical habitat 
continued to flow, even though groundwater pumping was at its highest 
rate and the area was experiencing extreme drought (McCord et al. 2007, 
p. 15). This suggests these springs and seeps may be somewhat resilient 
to reduced water levels, although climate change may test that 
resiliency. Models suggest climate change may cause the southwestern 
United States to experience the greatest temperature increase of any 
area in the lower 48 States (IPCC 2007, p. 15). There is also high 
confidence that many semi-arid areas like the western United States 
will suffer a decrease in water resources due to climate change (IPCC 
2007, p. 16), as a result of less annual mean precipitation and reduced 
length of snow season and snow depth (Christensen et al. 2007, p. 850). 
These predictions underscore the importance of maintaining aquifer 
levels to ensure survival of the four invertebrates.
    The primary threat to Pecos assiminea in Texas is the potential 
failure of spring flow due to excessive groundwater pumping or drought 
or both, which would result in total habitat loss for the species. 
Diamond Y Spring is the last major spring still flowing in Pecos 
County, Texas (Veni 1991, p. 2). Pumping of the regional aquifer system 
for agricultural production of crops has resulted in the drying of most 
other springs in this region (Brune 1981, p. 356). Other springs that 
have already failed include Comanche Springs, which was once a large 
spring in Fort Stockton, Texas, about 8 mi (12.9 km) from Diamond Y 
Spring. Comanche Springs flowed at more than 142 cubic feet per second 
(cfs) (4.0 cubic meters per second (cms)) (Scudday 1977, p. 515; Brune 
1981, p. 358) and undoubtedly provided habitat for rare species of fish 
and invertebrates, including springsnails. The spring ceased flowing by 
1962 (Brune 1981, p. 358) except for brief periods (Small and Ozuna 
1993, p. 26). Leon Springs, located upstream of Diamond Y Spring in the 
Leon Creek watershed, was measured at 18 cfs (0.5 cms) in the 1930s and 
was also known to contain rare fish, but ceased flowing in the 1950s 
following significant irrigation pumping (Brune 1981, p. 359). There 
have been no continuous records of spring flow discharge at Diamond Y 
Spring by which to determine trends in spring flow.
    East Sandia Spring discharges at an elevation of 3,205 ft (977 m) 
from alluvial sand and gravel (Schuster 1997, pp. 92-93). Brune (1981, 
pp. 385-386) noted that flows from East Sandia Springs were declining. 
East Sandia Spring may be very susceptible to over-pumping in the area 
of the local aquifer that supports the spring. Measured discharges in 
1995 and 1996 ranged from 0.45 to 4.07 cfs (0.013 to 0.11 cms) 
(Schuster 1997, p. 94). The small outflow channel from East Sandia 
Spring has not been significantly modified, and water flows into an 
irrigation system approximately 328 to 656 ft (100 to 200 m) after 
surfacing.
Water Contamination
    Water contamination, particularly from oil and gas operations, is a 
significant threat for these four invertebrates. In order to assess the 
potential for contamination, a study was completed in September 1999 to 
delineate the area that serves as sources of water for the springs on 
the Refuge (Balleau et al. 1999, pp. 1-42). This study reported that 
the sources of water that will reach the Refuge's springs include a 
broad area beginning west of Roswell near Eightmile Draw, extending to 
the northeast to Salt Creek, and southeast to the Refuge. This area 
represents possible pathways that contaminants may enter the 
groundwater that feeds the springs on the Refuge. This broad area sits 
within a portion of the Roswell Basin and contains a mosaic of Federal, 
State, and private lands with multiple land uses including expanding 
urban development.
    There are 378 natural gas and oil wells in the 12-township area 
encompassing the source-water capture zone for the Middle Tract of the 
Refuge (the only tract on which these species are found) that are 
potential sources of contamination (Go-Tech 2010). Of these, 17 oil and 
gas leases are currently within the habitat protection zone designated 
by the Bureau of Land Management (BLM) to reduce risk from drilling 
operations to the four invertebrates. This habitat protection zone 
encompasses 12,585 ac (5,093 ha) of the Federal mineral estate within 
the water resource area for the Refuge (U.S. Fish and Wildlife Service 
(Service) 2005a, pp. 3-8). Twenty natural gas wells currently exist on 
these leases. The BLM has estimated a maximum potential development of 
66 additional wells within the habitat protection zone, according to 
well spacing requirements established by the New Mexico Oil 
Conservation Division (Service 2005a, p. 4-6). From 2002 to 2004, there 
were 200 notices of ``intentions to drill'' (59 on State, 33 on 
private, and 108 on Federal lands) filed for oil or natural gas in 
Chaves County (Go-Tech 2005).
    There are numerous examples in which oil and gas operations have 
met regulatory standards within karst lands

[[Page 35381]]

in New Mexico and other States, but these measures failed to protect 
groundwater resources and prevent aquifer drawdown (McCord et al. 2007, 
p. 8). To clean the aquifer would be extremely difficult should it 
become contaminated by oil, chemicals, or organics, such as nitrates. 
In most cases, contamination of an underground aquifer by agricultural, 
industrial, or domestic sources is treated only at the source. When a 
contamination site is discovered, the source of the contamination is 
treated, and rarely do remediation efforts pump water from the aquifer 
and treat it before sending it back. This is largely because these 
techniques are very costly and difficult to apply (S. McGrath, pers. 
comm. 2001). Because these invertebrate species are sensitive to 
contaminants, efforts to clean up pollution after the aquifer has been 
contaminated may not be sufficient to protect these species and the 
aquatic habitat on which they depend.
    Currently there are two active gas wells on the Middle Tract of the 
Refuge that are upstream (within the underground watershed) of occupied 
habitat for the four invertebrates. In 2006, Yates Petroleum applied 
for two additional gas wells, one of which would have been just 
upstream of occupied habitat for the four invertebrates. The 
applications have since been withdrawn, although the potential for oil 
and gas development remains.
    The Diamond Y Springs Complex is within an active oil and gas 
extraction field. At this time there are still many active wells and 
pipelines located within a hundred meters of the surface waters at the 
springs. In addition, a natural gas refinery is located within 0.5 mi 
(0.8 km) upstream of Diamond Y Spring. There are also old brine pits, 
which can contribute salt and other mineral pollutants to the 
groundwater, associated with previous drilling within feet of surface 
waters. In addition, oil and gas pipelines cross the spring outflow 
channels and marshes where the species occurs, creating a constant 
potential for contamination from pollutants from leaks or spills. These 
activities pose a threat to the habitat of the Pecos assiminea by 
creating the potential for pollutants to enter underground aquifers 
that contribute to spring flow or by point sources from spills and 
leaks of petroleum products on the surface.
    As an example of the likelihood of a spill occurring, in 1992 
approximately 10,600 barrels of crude oil were released from a 6-in 
(15.2 cm) pipeline that traverses Leon Creek above its confluence with 
Diamond Y Draw. The oil was from a ruptured pipeline at a point several 
hundred feet away from the Leon Creek channel. The site itself is about 
1 mi (1.6 km) overland from Diamond Y Spring. The distance that surface 
runoff of oil residues must travel is about 2 mi (3.2 km) down Leon 
Creek to reach Diamond Y Draw. The pipeline was operated at the time of 
the spill by the Texas-New Mexico Pipeline Company, but ownership has 
since been transferred to several other companies. The Texas Railroad 
Commission has been responsible for overseeing cleanup of the spill 
site. Remediation of the site initially involved aboveground land 
farming of contaminated soil and rock strata to allow microbial 
degradation. In recent years, remediation efforts have focused on 
vacuuming oil residues from the surface of groundwater exposed by 
trenches dug at the spill site. No impacts on the rare fauna of Diamond 
Y Springs Complex have been observed, but no specific monitoring of the 
effects of the spill was undertaken (Service 2005a, pp. 4-12).
Fire
    Fire suppression efforts on the Refuge are largely restricted to 
established roads due to the safety hazards of transporting equipment 
over karst terrain. This severely limits the ability to quickly 
suppress fires that threaten fragile aquatic habitats on the Refuge. On 
March 5, 2000, the Sandhill wildfire burned 1,000 ac (405 ha) of the 
western portion of the Refuge, including portions of Bitter Creek. The 
fire burned through Dragonfly Spring, a spring in the headwaters of 
Bitter Creek, which is occupied habitat for Noel's amphipod and 
Koster's springsnail. The fire eliminated vegetation shading the 
spring, and generated a substantial amount of ash in the spring system 
(Lang 2002, p. 3; NMDGF 2005, p. 15). This resulted in the formation of 
dense algal mats, increased water temperature fluctuations, increased 
maximum water temperatures, and decreased dissolved oxygen levels (Lang 
2002, pp. 5-6). The pre-fire dominant vegetation of submerged aquatic 
plants and mixed native grasses within the burned area has also been 
replaced by the invasive common reed (Phragmites australis) (NMDGF 
2005, p. 15; 2008, p. 8). Following the fire at Dragonfly Spring, a 
dramatic reduction in Noel's amphipod was observed, and Koster's 
springsnail presently occurs at lower densities than were observed 
prior to the fire (Lang 2002, p. 7; NMDGF 2006a, p. 9). Strategically 
timed prescribed burns throughout the range of the species would 
significantly reduce fuel loads, limiting the risk of detrimental 
wildfires.
    Removal of vegetative cover by burning in habitats occupied by 
Pecos assiminea may be an important factor in decline or loss of 
populations (Taylor 1987, p. 5, NMDGF 2005, p. 16). It is likely that 
Pecos assiminea may survive fire or other vegetation reduction if 
sufficient litter and ground cover remain to sustain appropriate soil 
moisture and humidity at a microhabitat scale (NMDGF 2005, p. 16; 
Service 2004, pp. 4-5). Complete combustion of vegetation and litter, 
high soil temperatures during fire, or extensive vegetation removal 
resulting in soil and litter drying may create unsuitable habitat 
conditions and loss of populations (NMDGF 2005, p. 16). Pecos assiminea 
was discovered at Dragonfly Spring following the burning of habitat 
there during the Sandhill Fire (NMDGF 2005, p. 16). Season of burning, 
intensity of the fire, and frequency of fire likely determine the 
magnitude of the fire's effects on Pecos assiminea population 
persistence and abundance (NMDGF 2005, p. 16), as the species has been 
found to persist in areas following fires (Lang 2002, p. B8). Pecos 
assiminea is relatively vulnerable to fires because the assiminea 
resides at or near the surface of the water.
Introduced Species
    Introduced species are one of the most serious threats to native 
aquatic species (Williams et al. 1989, p. 18; Lodge et al. 2000, p. 7). 
Because the distribution of the four invertebrates is so limited, and 
their habitat so restricted, introduction of certain nonnative species 
into their habitat could be devastating. Several invasive terrestrial 
plant species that may affect the invertebrates are present on the 
Refuge, including saltcedar (Tamarix ramossisima), common reed, and 
Russian thistle (Salsola spp.). Control and removal of nonnative 
vegetation has been identified as a factor responsible for localized 
extirpations of populations of Pecos assiminea in Mexico and New Mexico 
(Taylor 1987, p. 5). Saltcedar, found on the Refuge and at Diamond Y 
Spring Complex and East Sandia Spring, threatens spring habitats 
primarily through the amount of water it consumes and from the chemical 
composition of the leaves that drop to the ground and into the springs. 
Saltcedar leaves that fall to the ground and into the water add salt to 
the system, as their leaves contain salt glands (DiTomaso 1998, p. 
333). Additionally, dense stands of common reed choke the stream 
channel, slowing water velocity and creating more pool-like habitat; 
this habitat is less suitable for Roswell and Koster's springsnails,

[[Page 35382]]

which prefer flowing water. Finally, Russian thistle (tumbleweed) can 
create problems in spring systems by being blown into the channel, 
slowing flow and overloading the system with organic material (Service 
2005b, p. 2).
    Nonnative mollusks have affected the distribution and abundance of 
native mollusks in the United States. Of particular concern for three 
of the invertebrates (Noel's amphipod, Roswell springsnail, and 
Koster's springsnail) is the red-rim melania (Melanoides tuberculata), 
a snail that can reach tremendous population sizes and has been found 
in isolated springs in the west. The red-rim melania has caused the 
decline and local extirpation of native snail species, and it is 
considered a threat to endemic aquatic snails that occupy springs and 
streams in the Bonneville Basin of Utah (Rader et al. 2003, p. 655). It 
is easily transported on fishing boats and gear or aquatic plants, and 
because it reproduces asexually (individuals can develop from 
unfertilized eggs), a single individual is capable of founding a new 
population. It has become established in isolated desert spring 
ecosystems such as Ash Meadows, Nevada, and Cuatro Cienegas, Mexico, 
and within the last 15 years, the red-rim melania has become 
established in Diamond Y Springs Complex (Echelle 2001, p. 18). It has 
become the most abundant snail in the upper watercourse of the Diamond 
Y Springs Complex (Echelle 2001, p. 14). In many locations, this exotic 
snail is so numerous that it essentially is the substrate in the small 
stream channel. The effect the species is having on native snails is 
not known; however, because it is aquatic it probably has less effect 
on Pecos assiminea than on the other endemic aquatic snails present in 
the spring.

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 Roswell springsnail, Koster's 
springsnail, Noel's amphipod, and Pecos assiminea, as well as in 
determining if areas outside of the geographical area occupied at the 
time of listing are essential for the conservation of the four 
invertebrates. We relied on information from knowledgeable biologists 
and recommendations contained in State wildlife resource reports (Cole 
1985; Jones and Balleau 1996, pp. 1-16; Boghici 1997, pp. 1-120; 
Balleau et al. 1999, pp. 1-42; NMDGF 1999, pp. A1-B46; NMDGF 2006b, pp. 
1-16; NMDGF 2007, pp. 1-20; and NMDGF 2008, pp. 1-28) and the State 
recovery plan (NMDGF 2005, pp. 1-80) in making this determination. We 
also reviewed the available literature pertaining to habitat 
requirements, historic localities, and current localities for these 
species. This includes data submitted during section 7 consultations 
and regional geographic information system (GIS) coverages.
    In proposing designation of revised critical habitat for the Pecos 
assiminea, and critical habitat for Roswell springsnail, Koster's 
springsnail, and Noel's amphipod,, we selected areas based on the best 
scientific data available that possess those PCEs essential to the 
conservation of the species that may require special management 
considerations or protection. We identified critical habitat units that 
have the highest likelihood to contain populations of the four 
invertebrates based on the presence of the defined PCEs and the kind, 
amount, and quality of habitat associated with those occurrences. The 
units contain the appropriate quantity and distribution of PCEs to 
support the life cycle stages we have determined are essential to the 
conservation of the species.
    The four invertebrates currently exist throughout their ranges in a 
spatial arrangement that would provide for their long-term 
conservation. For this reason, we are not currently proposing any areas 
outside the geographical area presently occupied by the species, 
because the occupied areas are sufficient for the conservation of the 
species.
    When determining revised critical habitat boundaries within this 
proposed rule, we made every effort to avoid including structures such 
as culverts and roads, because areas with such structures lack PCEs for 
Roswell springsnail, Koster's springsnail, Noel's amphipod, and Pecos 
assiminea. The scale of the maps we prepared under the parameters for 
publication within the Code of Federal Regulations may not reflect the 
exclusion of such areas. Any such structures inadvertently left inside 
critical habitat boundaries shown on the maps of this proposed rule 
have been excluded by text in the proposed rule and are not proposed 
for designation as critical habitat. Therefore, if the critical habitat 
were finalized as proposed, a Federal action involving these areas 
would not trigger section 7 consultation with respect to critical 
habitat and the requirement of no adverse modification unless the 
specific action would affect the PCEs in the adjacent critical habitat.
Essential Areas
    For areas not occupied by the species at the time of listing, the 
Service must demonstrate that these areas are essential to the 
conservation of the species in order to include them in a critical 
habitat designation. The four invertebrates are not migratory, nor is 
there frequent gene exchange between populations or critical habitat 
units. Further, the proposed critical habitat units in New Mexico and 
west Texas are sufficiently distant (40 to 100 mi (64 to 161 km)) from 
one another to rule out Pecos assiminea gene exchange. Therefore, due 
to the lack of frequent gene exchange, we have determined that each of 
these populations is essential to the conservation of the species 
because they provide for the maintenance of the genetic diversity of 
the four invertebrates. The areas we have determined meet the 
definition of critical habitat for the four invertebrates include 
populations containing all of the known remaining genetic diversity 
within each species.
    Locations from within the historical range of the four 
invertebrates, including North Spring, Berrendo Spring, South Spring 
River, and Lander Springbrook, are no longer suitable habitat for the 
four invertebrates, and the species have been extirpated from these 
sites. South Spring and Lander Spring are both dry due to aquifer 
depletion (Cole 1981, p. 27; Jones and Balleau 1996, p. 5), and reaches 
of Berrendo Creek (the springbrook from Berrendo Spring) remain dry and 
unable to support the invertebrates (NMDGF 2005, p. 18). North Spring, 
located on the grounds of the Roswell Country Club, was enclosed by a 
brick wall, native vegetation was removed from the margins of the 
springhead and springbrook, and the banks were sodded (Cole, 1988, p. 
2; NMDGF 2005, p. 18). The brick wall at North Spring has since been 
removed and the spring outflow has been widened, allowing a nearby pond 
to back into the spring, introducing carp to the system (B. Lang, 
NMDGF, pers. comm., 2010). Springsnails have not been found at North 
Spring since 1995, and suitable habitat is not present there. Because 
these formerly occupied sites have been so severely impacted in the 
past, it is not likely that they could be rehabilitated in the future 
and once again contain suitable habitat for the four invertebrates; 
therefore, they are unlikely to contribute to the recovery of the 
species and not considered essential to the conservation of the 
species.

[[Page 35383]]

Occupancy
    We consider an area to be currently occupied if Roswell 
springsnail, Koster's springsnail, Pecos assiminea, or Noel's amphipod 
were found to be present by species experts within the last 5 years and 
no major habitat modification has occurred which would preclude their 
presence. Five years is an appropriate time period because surveys may 
not occur in all areas in all years. The species would be likely to 
persist in an area over multiple years unless major habitat 
modification occurred. We are proposing to designate as critical 
habitat all sites on or near the Refuge currently occupied by at least 
one of the four invertebrates.
    In summary, this proposed critical habitat designation includes 
populations of the four invertebrates and habitats that possess the 
physical and biological features essential to the conservation of the 
species. We believe the populations included in this designation, if 
secured, would provide for the conservation of the Roswell springsnail, 
Koster's springsnail, Pecos assiminea, and Noel's amphipod by:
    (1) Maintaining the physical and biological features essential to 
the conservation of the species in areas where populations of the four 
invertebrates are known to occur, and
    (2) Maintaining the current distribution, thus preserving genetic 
variation throughout the ranges of the four invertebrates and 
minimizing the potential effects of local extinction.

Summary of Changes from Previously Proposed and Designated Critical 
Habitat

    The areas identified in this proposed rule constitute a proposed 
revision of the areas we designated as critical habitat for the Pecos 
assiminea on August 9, 2005 (70 FR 46304). The significant differences 
between the 2005 rule and this proposal include the following:
    (1) Currently, two units in Texas (Diamond Y Spring complex and 
East Sandia Springs) totaling 396.5 ac (160.5 ha) are designated as 
critical habitat for the Pecos assiminea (70 FR 46304, August 9, 2005). 
We did not designate any areas as critical habitat for the Roswell 
springsnail, Koster's springsnail, and Noel's amphipod in 2005, nor did 
we designate any lands of the Bitter Lake National Wildlife Refuge 
(Refuge) as critical habitat for these species. This proposed rule, 
which is based partly on new occupancy information since we originally 
proposed critical habitat, includes two units on the Refuge totaling 
67.8 ac (27.4 ha). If adopted, this proposed rule would result in an 
increase of 70.6 ac (28.6 ha) from currently designated critical 
habitat for the Pecos assiminea and would include new critical habitat 
for the Roswell springsnail, Koster's springsnail, and Noel's amphipod.
    (2) As stated above, our 2005 critical habitat designation (70 FR 
46304; August 9, 2005) did not include any Refuge lands. In that rule, 
we determined that Refuge lands did not meet the definition of critical 
habitat in section 3(5)(A) of the Act because the special management 
for the four invertebrates was already occurring on the Refuge. In 
order to more fully consider special management of threats that may be 
occurring outside the Refuge boundaries, we are now proposing certain 
Refuge lands for critical habitat designation.
    (3) In our February 12, 2002, proposal to designate critical 
habitat for the four invertebrates (67 FR 6459) we proposed 1,127 ac 
(456 ha) of critical habitat on the Refuge. This proposed designation 
of critical habitat includes only 67.8 ac (27.4 ha) on the Refuge; 
updated GIS techniques have allowed us to more closely map the 
wetlands, springs, and seeps on the Refuge in which the four 
invertebrates occur.
    (4) This proposed designation of critical habitat includes 2.8 ac 
(1.1 ha) in one unit in the city of Roswell, New Mexico, adjacent to 
the Refuge that are not currently designated as critical habitat. We 
did not include this site in the August 9, 2005, designation (70 FR 
46304) because occupancy by Noel's amphipod and Koster's springsnail 
was first documented following publication of the proposed rule to 
designate critical habitat (67 FR 6459; February 12, 2002).
    (5) This proposed designation of critical habitat includes the two 
units in Texas (Diamond Y Spring complex and East Sandia Springs) 
currently designated for Pecos assiminea, but we have used updated GIS 
information to offer more refined boundaries within those two units. 
While the critical habitat boundary at Diamond Y Spring complex did not 
change, the acreage calculation increased from 380 ac (153.8 ha) in the 
2005 final rule (70 FR 46304, August 9, 2005) to 441.5 ac (178.7 ha) in 
this proposed rule. At East Sandia Spring, updated GIS techniques have 
allowed us to more closely map the wetlands, springs, and seeps in this 
area, resulting in fewer acres proposed for critical habitat; we 
designated 16.5 ac (6.7 ha) in 2005 (70 FR 46304, August 9, 2005), and 
we are proposing 3.0 ac (1.2 ha) for designation in this rule.
    (6) This proposed designation of critical habitat includes more 
detailed PCEs than we proposed for Roswell and Koster's springnails and 
Noel's amphipod in our 2002 proposal (67 FR 6459, February 12, 2002) or 
we adopted for Pecos assiminea in our 2005 designation (70 FR 46304, 
August 9, 2005); this detail adds clarity to the designation.
    (7) We are proposing as critical habitat all occupied sites for the 
four invertebrates, as all of these sites are essential to the 
conservation of the species.

Proposed Critical Habitat Designation

    We are proposing four units as critical habitat for the Roswell 
springsnail, Koster's springsnail, Noel's amphipod, and Pecos assiminea 
in New Mexico and Texas. The critical habitat areas we describe below 
constitute our current best assessment of areas that meet the 
definition of critical habitat for the four invertebrates. Roswell 
springsnail, Koster's springsnail, and Noel's amphipod occur in two of 
the four units; the two units we propose as critical habitat for these 
invertebrates, and their approximate areas, are displayed in Table 1. 
Pecos assiminea occurs in all four units; the four units we propose as 
revised critical habitat for this species, and their approximate areas, 
are displayed in Table 2. All locations were occupied at the time of 
listing and are currently occupied by the invertebrates.

    TABLE 1. Proposed critical habitat units for Roswell springsnail,
  Koster's springsnail, and Noel's amphipod [Area estimates reflect all
             land within critical habitat unit boundaries.]
------------------------------------------------------------------------
                                   Land Ownership by    Size of Unit in
      Critical Habitat Unit              Type          Acres (Hectares)
------------------------------------------------------------------------
1. Sago/Bitter Creek Complex      Service             31.9 (12.9)
=================================
2. Impoundment Complex            Service             35.9 (14.5)
                                  City of Roswell...  2.8 (1.1)
=================================

[[Page 35384]]

 
Total                                                 70.6 (28.6)
------------------------------------------------------------------------
Note: Area sizes may not sum due to rounding.


  TABLE 2. Proposed revised critical habitat units for Pecos assiminea.
      [Area estimates reflect all land within critical habitat unit
                              boundaries.]
------------------------------------------------------------------------
                                   Land Ownership by    Size of Unit in
      Critical Habitat Unit              Type          Acres (Hectares)
------------------------------------------------------------------------
1. Sago/Bitter Creek Complex      Service             31.9 (12.9)
=================================
2. Impoundment Complex            Service             35.9 (14.5)
                                  City of Roswell...  2.8 (1.1)
=================================
3. Diamond Y Springs Complex      The Nature          441.4 (178.6)
                                   Conservancy
=================================
4. East Sandia Spring             The Nature          3.0 (1.2)
                                   Conservancy
=================================
Total                                                 515.0 (208.4)
------------------------------------------------------------------------
Note: Area sizes may not sum due to rounding.

    We present brief descriptions of the units and reasons why the 
proposed critical habitat units meet the definition of critical habitat 
for the Roswell springsnail, Koster's springsnail, Noel's amphipod, and 
Pecos assiminea below.

Unit 1: Sago/Bitter Creek Complex

    Unit 1 consists of 31.9 ac (12.9 ha) of habitat that was occupied 
by all four invertebrates at the time of listing and that remains 
occupied at the present time. We propose to designate this unit as 
critical habitat for all four species; it contains all of the features 
essential to the conservation of these species. Unit 1 is located on 
the northern portion of the Middle Tract of Bitter Lake National 
Wildlife Refuge, Chaves County, New Mexico. The adjacent gypsum 
sinkholes comprise the core population center for all four species. The 
proposed designation includes all springs, seeps, sinkholes, and 
outflows surrounding Bitter Creek and the Sago Springs complex. Habitat 
in this unit is threatened by subsurface drilling or similar activities 
that contaminate surface drainage or aquifer water; wildfire; nonnative 
fish, crayfish, snails, and vegetation; and unauthorized activities, 
including dumping of pollutants or fill material into occupied sites. 
Therefore, the PCEs in this unit may require special management 
considerations or protection to minimize impacts resulting from these 
threats. The entire unit is owned by the Service.

Unit 2: Impoundment Complex

    Unit 2 consists of 38.7 ac (15.7 ha) of habitat that was occupied 
by the four invertebrates at the time of listing and that remains 
occupied at the present time. We propose to designate this unit as 
critical habitat for all four species; it contains all of the features 
essential to the conservation of these species. Unit 2 is located on 
the southern portion of the Middle Tract of Bitter Lake National 
Wildlife Refuge and on property owned by the city of Roswell, Chaves 
County, New Mexico. This unit includes portions of impoundments 3, 6, 
7, 15, and Hunter Marsh. This unit comprises a secondary population 
center for all four invertebrates. The proposed designation includes 
all springs, seeps, sinkholes, and outflows surrounding the Refuge 
impoundments. Habitat in this unit is threatened by subsurface drilling 
or similar activities that contaminate surface drainage or aquifer 
water; wildfire; nonnative fish, crayfish, snails, and vegetation; and 
unauthorized activities, including dumping of pollutants or fill 
material into occupied sites. Therefore, the PCEs in this unit may 
require special management considerations or protection to minimize 
impacts resulting from these threats. Land ownership in this unit 
includes the Service and the City of Roswell, New Mexico.

Unit 3: Diamond Y Springs Complex, Pecos County, Texas

    This unit comprises a major population of Pecos assiminea and 
contains all of the features essential to the conservation of that 
species. We propose to designate this unit as critical habitat only for 
Pecos assiminea; the unit was occupied by that species at the time of 
listing. The proposed designation includes the Diamond Y Spring and 
approximately 4.2 mi (6.8 km) of its outflow, ending at approximately 
0.5 mi (0.8 km) downstream of the State Highway 18 bridge crossing. 
Also included in this proposed unit is approximately 0.5 mi (0.8 km) of 
Leon Creek upstream of the confluence with Diamond Y Draw. All 
surrounding riparian vegetation and mesic (wet) soil environments 
within the spring, outflow, and portion of Leon Creek are also proposed 
for designation, as these areas are considered habitat for the Pecos 
assiminea. This proposed designation is approximately 441 ac (178.6 ha) 
of aquatic and neighboring mesic habitat. Habitat in this unit is 
threatened by increased groundwater pumping; subsurface drilling or 
similar activities that contaminate surface drainage or aquifer water; 
wildfire; and nonnative fish, crayfish, snails, and vegetation. This 
complex occurs entirely on private lands. Private land in the immediate 
vicinity of the Diamond Y Springs Complex is managed as a nature 
preserve by The Nature Conservancy (TNC).

Unit 4: East Sandia Spring, Reeves County, Texas

    East Sandia Spring is at the base of the Davis Mountains just east 
of Balmorhea, Texas, and is part of the San Solomon-Balmorhea Spring 
Complex, the largest remaining desert spring system in Texas where the 
Pecos assiminea is found. We propose to designate this unit as critical 
habitat only for Pecos assiminea; the unit was occupied by that species 
at the time of listing. The proposed designation

[[Page 35385]]

includes the springhead itself, surrounding seeps, and all submergent 
vegetation and moist soil habitat found at the margins of these areas, 
comprising the PCEs for the Pecos assiminea. This proposed designation 
is approximately 3.0 ac (1.2 ha) of aquatic and neighboring upland 
habitat. Habitat in this unit is threatened by increased groundwater 
pumping; wildfire; and nonnative fish, crayfish, snails, and 
vegetation. The spring is included in a 240-ac (97-ha) preserve owned 
and managed by TNC (Karges 2003, p. 145).

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 (9\th\ Cir. 2004) and Sierra Club v. U.S. Fish and Wildlife 
Service et al., 245 F.3d 434, 442 (5\th\ 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 PCEs 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:
     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 the Roswell springsnail, 
Koster's springsnail, Noel's amphipod, and Pecos assiminea 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 ``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 PCEs 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 PCEs to an extent that appreciably reduces the conservation 
value of critical habitat for the Roswell springsnail, Koster's 
springsnail, Noel's amphipod, and Pecos assiminea. As discussed above, 
the role of critical habitat is to support the life history needs of 
the species and provide for the conservation 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 section 7 consultation for the Roswell springsnail, Koster's 
springsnail, Noel's amphipod, and Pecos assiminea include, but are not 
limited to:
    (1) Actions that would contaminate or cause significant degradation 
of habitat occupied by these species, including surface drainage water 
or aquifer water quality. Such activities could include, but are not 
limited to, the use of chemical insecticides or herbicides that results 
in killing or injuring these species; subsurface drilling or similar 
activities within the 12,585-ac (5,093-ha) Federal mineral estate and 
9,945-ac (4,025-ha) habitat protection zone in New Mexico (e.g., Bureau 
of Land Management 2002, p. 1; Balleau et al. 1999, p. 3) that 
contaminate or cause significant degradation of water quality in 
surface or aquifer waters supporting the habitat occupied by these 
species; septic tank placement and use where the groundwater is 
connected to sinkhole or other aquatic habitats occupied by these 
species; and unauthorized discharges or dumping of

[[Page 35386]]

toxic chemicals or other pollutants into the areas supporting the four 
invertebrates. These activities could alter water conditions to levels 
that are beyond the tolerances of the invertebrates and result in 
degradation of their occupied habitat to an extent that individuals are 
killed or injured or essential behaviors such as breeding, feeding, and 
sheltering are impaired.
    (2) Actions that would destroy or alter habitat for the four 
invertebrates. Such activities could include, but are not limited to, 
discharging fill material into occupied sites, draining, ditching, 
tilling, channelizing, drilling, pumping, or other activities that 
interrupt surface or groundwater flow into or out of the spring 
complexes and occupied habitats of these species. These activities 
could result in significant impairment of essential life-sustaining 
requirements such as breeding, feeding, and sheltering.
    (3) Actions that would introduce nonnative species into occupied 
habitats for the four invertebrates. Potential nonnative species 
include, but are not limited to, mosquitofish, crayfish, nonnative 
snails, or vegetation into habitat currently occupied by any of the 
four invertebrates. These species compete for scarce resources and may 
prey on the four species.

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 areas we are 
proposing to designate as critical habitat for the four invertebrates; 
therefore we are not exempting any areas from 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 designation, we must 
identify the benefits of including the area in the designation, 
identify the benefits of excluding the area from the 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 the area 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 whether the 
benefits of exclusion outweigh those of inclusion. If we determine that 
they do, we then determine whether exclusion would result in 
extinction. 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 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.
    A draft analysis of the economic effects of the proposed critical 
habitat designation was prepared and with this proposed rule is made 
available for public review. The economic analysis considers the 
economic impacts of conservation measures taken prior to and subsequent 
to the final listing and designation of critical habitat for the four 
invertebrates. Baseline impacts are typically defined as all management 
efforts that have occurred since the time of listing. We listed the 
four invertebrates in August 2005 (70 FR 46304). Incremental costs are 
those that are attributable to critical habitat designation alone. 
Total baseline costs associated with this proposed critical habitat 
designation are estimated to be $1,080,000 to $1,490,000 over the next 
30 years, and incremental costs are estimated to be $5,900 to $62,500.
    Copies of the draft economic analysis are available for downloading 
from the Internet at http://www.regulations.gov,

[[Page 35387]]

or by contacting the New Mexico Ecological Services Field Office (see 
FOR FURTHER INFORMATION CONTACT). During the development of a final 
designation, we will consider economic impacts, public comments, and 
other new information, and we may exclude areas from the revised 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 
have determined that the lands within the proposed designation of 
critical habitat for the Roswell springsnail, Koster's springsnail, 
Noel's amphipod, and Pecos assiminea are not owned or managed by the 
DOD. We are aware that there are DOD lands are in the vicinity of the 
Refuge, but our proposed designation does not include these lands, and 
we anticipate no impact to national security. Therefore, there are no 
areas proposed for exclusion 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 on national 
security. We consider a number of factors, including whether the 
landowners have developed any habitat conservation plans (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.
    In preparing this proposal, we have determined that there are 
currently no HCPs for the Roswell springsnail, Koster's springsnail, 
Noel's amphipod, and Pecos assiminea, and the proposed designation does 
not include any tribal lands or trust resources. We anticipate no 
impact to tribal lands, partnerships, or HCPs from this proposed 
critical habitat designation. There are no areas proposed for exclusion 
from this proposed designation based on other relevant impacts.
    We have determined that areas managed by the Refuge meet the 
definition of critical habitat for the four invertebrates. The Refuge 
has developed and completed a Comprehensive Conservation Plan (CCP) 
that provides the framework for protection and management of all trust 
resources, including federally listed species and sensitive natural 
habitats. These lands are protected areas for wildlife and are 
currently managed for the conservation of wildlife, including 
endangered and threatened species, and specifically the four 
invertebrates. Below we provide a description of the management being 
provided by the Refuge for the conservation of the four invertebrates 
within areas proposed for designation as critical habitat.
    The Refuge was established on October 8, 1937, by Executive Order 
7724 ``as a refuge and breeding ground for migratory birds and other 
wildlife.'' The Refuge Recreation Act (16 U.S.C. 460k-460k-4) 
identifies the refuge as being suitable for incidental fish and 
wildlife-oriented recreational development, the protection of natural 
resources, and the conservation of endangered species or threatened 
species. While the Refuge was originally established to save wetlands 
vital to the perpetuation of migratory birds, the isolated gypsum 
springs, seeps, and associated wetlands protected by the Refuge have 
been recognized as providing the last known habitats in the world for 
several unique species. Management emphasis of the Refuge is placed on 
the protection and enhancement of habitat for endangered species and 
Federal candidate species, maintenance and improvement of wintering 
crane and waterfowl habitat, and monitoring and maintenance of natural 
ecosystem values.
    The Refuge sits at a juncture between the Roswell Artesian 
Groundwater Basin and the Pecos River. These two systems and their 
interactions account for the diversity of water resources on the 
Refuge, including sinkholes, springs, wetlands, oxbow lakes, and 
riverine habitats. The Refuge has a federally reserved water right that 
essentially protects groundwater levels of the Roswell Basin in the 
Refuge vicinity. The Refuge has undergone adjudication of its federally 
reserved water rights by the State of New Mexico (order signed May 
1997).
    The National Wildlife Refuge System Improvement Act of 1997 (Refuge 
Improvement Act; Pub. L. 105-57, 111 Stat. 1252-1260) establishes a 
conservation mission for refuges, gives policy direction to the 
Secretary of the Interior and refuge managers, and contains other 
provisions such as the requirement to integrate scientific principals 
into the management of the refuges. According to section 7 of the 
Refuge Improvement Act, all lands of the Refuge System are to be 
managed in accordance with an approved CCP that will guide management 
decisions and set forth strategies for achieving refuge purposes. In 
general, the purpose of the CCP is to provide long-range guidance for 
the management of National Wildlife Refuges. The Refuge Improvement Act 
requires all refuges to have a CCP and provides the following 
legislative mandates to guide the development of the CCP: (1) Wildlife 
has first priority in the management of refuges; (2) wildlife-dependent 
recreation, including hunting, fishing, wildlife observation, wildlife 
photography, environmental education and environmental interpretation, 
are the priority public uses of the Refuge System and shall be allowed 
when compatible with the refuge purpose; and (3) other uses have lower 
priority in the Refuge System and are only allowed if not in conflict 
with any of the priority uses and determined appropriate and compatible 
with the refuge purpose. The CCP must also be revised if the Secretary 
determines that conditions that affect the refuge or planning unit have 
changed significantly. In other words, a CCP must be followed once it 
is approved and regularly updated in response to environmental changes 
or new scientific information.
    The Refuge has a Final CCP that was approved in September 1998. The 
CCP serves as a management tool to be used by the Refuge staff and its 
partners in the preservation and restoration of the ecosystem's natural 
resources. The plan is intended to guide management decisions over the 
next 5 to 10 years and sets forth strategies for achieving Refuge goals 
and objectives within that timeframe. Key goals of the CCP related to 
the four invertebrates include the following: (1) To restore, enhance 
and protect the natural diversity on the Refuge, including endangered 
and threatened species by (a) appropriate management of habitat and 
wildlife resources on refuge lands and (b) strengthening existing and 
establishing new cooperative efforts with public and private 
stakeholders and partners, and (2) To restore and maintain selected 
portions of a hydrological system that more closely mimics the natural 
processes along the reach of the Pecos River adjacent to the Refuge by 
(a) restoration of the river channel as well as restoration of 
endangered, threatened , and special concern species; and (b) control 
of exotic species and management of trust responsibilities for 
maintenance of plant and animal

[[Page 35388]]

communities and to satisfy traditional recreational demands. Specific 
objectives related to these goals include: (1) The restoration of 
populations of aquatic species designated as endangered, threatened, or 
of special concern to a sustainable level (aquatic species in these 
categories include the four invertebrates), and (2) the monitoring of 
wildlife populations, including endemic snails.
    A final determination on whether we should exclude the Refuge from 
critical habitat for the four invertebrates 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.

Editorial Changes

    When we listed Roswell springsnail, Koster's springsnail, Noel's 
amphipod, and Pecos assiminea as endangered species on August 9, 2005 
(70 FR 46304), we neglected to insert the appropriate date code in the 
``When listed'' column of the List of Endangered and Threatened 
Wildlife at 50 CFR 17.11(h). Further, information we had intended to 
display in the ``Critical habitat'' column was misplaced under the 
``When listed'' column, and information intended for the ``Special 
rules'' column was misplaced under the ``Critical habitat'' column. We 
are proposing to correct these errors in this rule. This change is 
purely editorial; it would not affect the substance of the listing 
rule.

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 have invited 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

    The Act provides for one or more public hearings on this proposal, 
if requested. Requests must be received within 45 days after the date 
of publication of this proposed rule in the Federal Register. Such 
requests must be sent to the address shown in the FOR FURTHER 
INFORMATION CONTACT section. We will schedule public hearings on this 
proposal, if any are requested, and announce the dates, times, and 
places of those hearings, as well as how to obtain reasonable 
accommodations, in the Federal Register and local newspapers at least 
15 days before the 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 and has not reviewed this proposed rule 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.
    In the draft economic analysis of the proposed revised critical 
habitat designation, we evaluated the potential economic effects on 
small business entities resulting from conservation actions related to 
the listing of the Roswell springsnail, Koster's springsnail, Noel's 
amphipod, and Pecos assiminea (baseline costs), and the additional 
potential economic effects resulting from the proposed designation of 
their critical habitat (incremental costs). This analysis estimated 
prospective economic impacts due to the implementation of conservation 
efforts for the four invertebrates in five categories: (a) 
Modifications to oil and gas activities; (b) habitat management; (c) 
conservation of agricultural groundwater withdrawals; (d) control of 
residential septic systems; and (e) controls on confined animal feeding 
operations. We determined from our analysis that there will be minimal 
additional economic impacts to small entities resulting from the 
proposed designation of critical habitat, because almost all of the 
product modification and conservation costs identified in the economic 
analysis represent baseline costs that would be realized in the absence 
of critical habitat. There are several factors that eliminate the 
potential for incremental costs among small entities, including:
     Conservation measures implemented by New Mexico's oil and 
gas firms comply with BLM's Bitter Lake Habitat Restoration Zone 
requirements. Likewise, modifications pursued by oil and gas developers 
on private land near The Nature Conservancy units are already 
implemented for the benefit of various listed species in the immediate 
area.
     All of the proposed critical habitat is occupied. 
Therefore, ongoing project modifications and conservation measures are 
already required to satisfy the jeopardy standard.
     Most of the proposed critical habitat is already held in 
conservation. The small portion of proposed critical habitat owned by 
the City of Roswell has already been designated as critical habitat for 
the Pecos sunflower and is unsuitable for development.
     Habitat management costs are attributable to existing 
conservation agreements and are therefore classified as baseline costs.
     Most consultations under section 7 of the Act would be 
pursued in the absence of critical habitat. To the extent that 
incremental costs are introduced, they are borne by public agencies 
rather than private entities.
    The draft economic analysis estimates the annual incremental costs 
associated with the designation of critical habitat for the 
invertebrates to be very modest, at approximately $6,000. All of these 
costs would derive from the added effort associated with considering 
adverse

[[Page 35389]]

modification in the context of section 7 consultations.
    We will consider the information in our final economic analysis, 
and in any public comments we receive, in determining whether this 
designation would result in a significant economic effect on a 
substantial number of small entities, and announce our determination in 
our final rule. Based on the above reasoning and currently available 
information, it appears that this rule may not result in a significant 
economic impact on a substantial number of small entities. If we 
determine that is the case, then we will certify that the designation 
of critical habitat for the four invertebrates will not have a 
significant economic impact on a substantial number of small entities, 
and a regulatory flexibility analysis will not be required.

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 do not believe that this rule will significantly or uniquely 
affect small governments. The public lands we are proposing to 
designate as critical habitat are owned by the City of Roswell and the 
Service. Small governments, such as the City of Roswell, will be 
affected only to the extent that any programs having Federal funds, 
permits, or other authorized activities must ensure that their actions 
will not adversely affect the critical habitat. As discussed above, the 
areas owned by the City of Roswell which are being proposed for 
designation as critical habitat for the four invertebrates have already 
been designated as critical habitat for the Pecos sunflower and are 
unsuitable for development. Therefore, a Small Government Agency Plan 
is not required. However, we will further evaluate this issue as we 
complete our final economic analysis, and review and revise this 
assessment as appropriate.

Takings

    In accordance with E.O. 12630 (Government Actions and Interference 
with Constitutionally Protected Private Property Rights), we have 
analyzed the potential takings implications of designating critical 
habitat for the Roswell springsnail, Koster's springsnail, Noel's 
amphipod, and Pecos assiminea in a takings implications assessment. 
Critical habitat designation does not affect landowner actions that do 
not require Federal funding or permits, nor does it preclude 
development of habitat conservation programs or issuance of incidental 
take permits to permit actions that do require Federal funding or 
permits to go forward. The takings implications assessment concludes 
that this designation of critical habitat for the four invertebrates 
does not pose significant takings implications for lands within or 
affected by the designation.

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 New Mexico and Texas. 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 to 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 propose designating critical habitat in 
accordance with the provisions of the Act. This proposed rule uses 
standard property descriptions

[[Page 35390]]

and identifies the physical and biological features within the 
designated areas to assist the public in understanding the habitat 
needs of the Roswell springsnail, Koster's springsnail, Noel's 
amphipod, and Pecos assiminea.

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 Roswell springsnail, 
Koster's springsnail, Noel's amphipod, and Pecos assiminea, 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 assessment 
for this proposal when it is finished. This draft environmental 
assessment is available for review with the publication of this 
proposal. You may obtain a copy of the draft environmental assessment 
online at http://www.regulations.gov, by mail from the New Mexico 
Ecological Services Field Office (see FOR FURTHER INFORMATION CONTACT), 
or by visiting our website at http://www.fws.gov/southwest/es/NewMexico/.

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.
    We have determined that there are no tribal lands occupied at the 
time of listing that contain the features essential for the 
conservation, and no tribal lands that are essential for the 
conservation, of the Roswell springsnail, Koster's springsnail, Pecos 
assiminea, and Noel's amphipod. Therefore, we have not proposed 
designation of critical habitat for the four invertebrates on tribal 
lands.

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 it to significantly affect energy supplies, 
distribution, or use due to the small amount of habitat we are 
proposing for designation and the fact that the habitat is primarily on 
a National Wildlife Refuge. Therefore, we have made a preliminary 
determination that 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 complete our final economic analysis, and 
review and revise this assessment as appropriate.

References Cited

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

Authors

    The primary authors of this package are the staff members of the 
New Mexico Ecological Services Field 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.Amend Sec.  17.11(h) by revising the entries for:
    a. ``Pecos assiminea'', ``Springsnail, Koster's'', and 
``Springsnail, Roswell'' under SNAILS; and
    b. ``Amphipod, Noel's'' under CRUSTACEANS, in the List of 
Endangered and Threatened Wildlife to read as follows:


Sec.  17.11  Endangered and threatened wildlife.

* * * * *
    (h) * * *

[[Page 35391]]



--------------------------------------------------------------------------------------------------------------------------------------------------------
                    Species                                           Vertebrate
------------------------------------------------                   population where                                         Critical
                                                  Historic range     endangered or        Status         When listed        habitat       Special rules
         Common name            Scientific name                       threatened
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                      * * * * * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                         SNAILS
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                      * * * * * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------
Pecos assiminea                Assiminea pecos   U.S.A. (NM, TX)   NA                E                 770              17.95(f)         NA
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                      * * * * * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------
Springsnail, Koster's          Juturnia          U.S.A. (NM)       NA                E                 770              17.95(f)         NA
                                kosteria
--------------------------------------------------------------------------------------------------------------------------------------------------------
Springsnail, Roswell           Pyrgulopsis       U.S.A. (NM)       NA                E                 770              17.95(f)         NA
                                roswellensis
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                      * * * * * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                       CRUSTACEANS
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                      * * * * * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------
Amphipod, Noel's               Gammarus          U.S.A. (NM)       NA                E                 770              17.95(h)         NA
                                desperatus
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                      * * * * * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------

    2. Amend Sec.  17.95 by:
    a. In paragraph (f), revising the entry for ``Pecos Assiminea 
(Assiminea pecos)'' and adding an entry for ``Koster's springsnail 
(Juturnia kosteri) and Roswell springsnail (Pyrgulopsis roswellensis)'' 
in the same alphabetical order that those species appear in the table 
at 50 CFR 17.11(h), to read as follows; and
    b. In paragraph (h), adding an entry for ``Noel's amphipod 
(Gammarus desperatus)'' in the same alphabetical order that the species 
appears in the table at 50 CFR 17.11 (h), to read as follows.


Sec.  17.95  Critical habitat--fish and wildlife.

* * * * *
    (f) Clams and Snails.
* * * * *
Pecos assiminea (Assiminea pecos)
    (1) Critical habitat units are depicted for Chaves County, New 
Mexico, and Pecos and Reeves Counties, Texas, on the maps below.
    (2) The primary constituent element of critical habitat for the 
Pecos assiminea is moist or saturated soil at stream or spring run 
margins:
    (i) With native vegetation growing in or adapted to aquatic or very 
wet environment, such as salt grass or sedges;
    (ii) That consists of wet mud or occurs beneath mats of vegetation;
    (iii) That is within 1 inch (2 to 3 centimeters) of flowing water;
    (iv) That has native wetland plant species that provide leaf 
litter, shade, cover, and appropriate microhabitat;
    (v) That contains wetland vegetation adjacent to spring complexes 
that supports the algae, detritus, and bacteria needed for foraging;
    (vi) That has adjacent spring complexes with:
    (A) Permanent, flowing, unpolluted, fresh to moderately saline 
water; and
    (B) Stable water levels with natural diurnal and seasonal 
variations.
    (3) Critical habitat does not include manmade structures (such as 
buildings, aqueducts, runways, roads, and other paved areas) and the 
land on which they are located existing within the legal boundaries on 
the effective date of this rule.
    (4) Critical habitat map units. Data layers defining map units were 
created on a base of USGS 1:24,000 maps, and critical habitat units 
were then mapped using Universal Transverse Mercator (UTM) coordinates.
    (5) Unit 1: Sago/Bitter Creek Complex, Chaves County, New Mexico.
    (i) [Reserved for textual description of unit.]
    (ii) Map of Units 1 and 2 (Map 1) for Pecos assiminea follows:
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[[Page 35392]]

[GRAPHIC] [TIFF OMITTED] TP22JN10.006

    (6) Unit 2: Impoundment Complex, Chaves County, New Mexico.
    (i) [Reserved for textual description of unit.]
    (ii) Map of Unit 2 for Pecos assiminea is provided at paragraph 
(5)(ii) of this entry.
    (7) Unit 3: Diamond Y Springs Complex, Pecos County, Texas.
    (i) [Reserved for textual description of unit.]
    (ii) Map of Units 3 and 4 (Map 2) for Pecos assiminea follows:

[[Page 35393]]

[GRAPHIC] [TIFF OMITTED] TP22JN10.007

    (8) Unit 4: East Sandia Spring, Reeves County, Texas.
    (i) [Reserved for textual description of unit.]
    (ii) Map of Unit 4 for Pecos assiminea is provided at paragraph 
(7)(ii) of this entry.
* * * * *
Koster's springsnail (Juturnia kosteri) and Roswell springsnail 
(Pyrgulopsis roswellensis)
    (1) Critical habitat units are depicted for Chaves County, New 
Mexico, on the map below.

[[Page 35394]]

    (2) The primary constituent element of critical habitat for the 
Koster's springsnail and Roswell springsnail is springs and spring-fed 
wetland systems that:
    (i) Have permanent, flowing, unpolluted water;
    (ii) Have slow to moderate water velocities;
    (iii) Have substrates ranging from deep organic silts to limestone 
cobble and gypsum;
    (iv) Have stable water levels with natural diurnal (daily) and 
seasonal variations;
    (v) Consist of fresh to moderately saline water;
    (vi) Vary in temperature between 10-20 \o\C (50-68 \o\F) with 
natural seasonal and diurnal variations slightly above and below that 
range; and
    (vii) Provide abundant food, consisting of:
    (A) Algae, bacteria, and decaying organic material; and
    (B) Submergent vegetation that contributes the necessary nutrients, 
detritus, and bacteria on which these species forage.
    (3) Critical habitat does not include manmade structures (such as 
buildings, aqueducts, runways, roads, and other paved areas) and the 
land on which they are located existing within the legal boundaries on 
the effective date of this rule.
    (4) Critical habitat map units. Data layers defining map units were 
created on a base of USGS 1:24,000 maps, and critical habitat units 
were then mapped using Universal Transverse Mercator (UTM) coordinates.
    (5) Unit 1: Sago/Bitter Creek Complex, Chaves County, New Mexico.
    (i) [Reserved for textual description of unit.]
    (ii) Map of Units 1 and 2 for Koster's springsnail and Roswell 
springsnail follows:

[[Page 35395]]

[GRAPHIC] [TIFF OMITTED] TP22JN10.008

    (6) Unit 2: Impoundment Complex, Chaves County, New Mexico.
    (i) [Reserved for textual description of unit.]
    (ii) Map of Unit 2 for Koster's springsnail and Roswell springsnail 
is provided at paragraph (5)(ii) of this entry.
* * * * *
    (h) Crustaceans.
* * * * *
Noel's amphipod (Gammarus desperatus)
    (1) Critical habitat units are depicted for Chaves County, New 
Mexico, on the map below.
    (2) The primary constituent element of critical habitat for Noel's 
amphipod is

[[Page 35396]]

springs and spring-fed wetland systems that:
    (i) Have permanent, flowing, unpolluted water;
    (ii) Have slow to moderate water velocities;
    (iii) Have substrates including limestone cobble and aquatic 
vegetation;
    (iv) Have stable water levels with natural diurnal (daily) and 
seasonal variations;
    (v) Consist of fresh to moderately saline water;
    (vi) Have minimal sedimentation;
    (vii) Vary in temperature between 10-20 \o\C (50-68 \o\F) with 
natural seasonal and diurnal variations slightly above and below that 
range; and
    (viii) Provide abundant food, consisting of:
    (A) Submergent vegetation and decaying organic matter;
    (B) A surface film of algae, diatoms, bacteria, and fungi; and
    (C) Microbial foods, such as algae and bacteria, associated with 
aquatic plants algae, bacteria, and decaying organic material.
    (3) Critical habitat does not include manmade structures (such as 
buildings, aqueducts, runways, roads, and other paved areas) and the 
land on which they are located existing within the legal boundaries on 
the effective date of this rule.
    (4) Critical habitat map units. Data layers defining map units were 
created on a base of USGS 1:24,000 maps, and critical habitat units 
were then mapped using Universal Transverse Mercator (UTM) coordinates.
    (5) Unit 1: Sago/Bitter Creek Complex, Chaves County, New Mexico.
    (i) [Reserved for textual description of unit.]
    (ii) Map of Units 1 and 2 for Noel's amphipod follows:

[[Page 35397]]

[GRAPHIC] [TIFF OMITTED] TP22JN10.009

    (6) Unit 2: Impoundment Complex, Chaves County, New Mexico.
    (i) [Reserved for textual description of unit.]
    (ii) Map of Unit 2 for Noel's amphipod is provided at paragraph 
(5)(ii) of this entry.
* * * * *

    Dated: June 2, 2010
Eileen Sobeck,
Acting Assistant Secretary for Fish and Wildlife and Parks.
[FR Doc. 2010-15067 Filed 6-21-10; 8:45 am]
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