[Federal Register Volume 72, Number 220 (Thursday, November 15, 2007)]
[Rules and Regulations]
[Pages 64286-64340]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 07-5551]



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Part II





Department of the Interior





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Fish and Wildlife Service



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50 CFR Part 17



Endangered and Threatened Wildlife and Plants; Designation of Critical 
Habitat for Five Endangered and Two Threatened Mussels in Four 
Northeast Gulf of Mexico Drainages; Final Rule

  Federal Register / Vol. 72, No. 220 / Thursday, November 15, 2007 / 
Rules and Regulations  

[[Page 64286]]


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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

RIN 1018-AU87


Endangered and Threatened Wildlife and Plants; Designation of 
Critical Habitat for Five Endangered and Two Threatened Mussels in Four 
Northeast Gulf of Mexico Drainages

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Final rule.

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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), are 
designating critical habitat for the endangered fat threeridge (Amblema 
neislerii), shinyrayed pocketbook (Lampsilis subangulata), Gulf 
moccasinshell (Medionidus penicillatus), Ochlockonee moccasinshell 
(Medionidus simpsonianus), and oval pigtoe (Pleurobema pyriforme), and 
the threatened Chipola slabshell (Elliptio chipolaensis) and purple 
bankclimber (Elliptoideus sloatianus) (collectively referred to as the 
seven mussels) under the Endangered Species Act of 1973, as amended 
(Act). The total length of streams designated is approximately 1,185.9 
river miles (river mi) (1,908.5 river kilometers (river km)). The 
critical habitat is located in Houston and Russell counties, Alabama; 
in Alachua, Bay, Bradford, Calhoun, Columbia, Franklin, Gadsden, Gulf, 
Jackson, Leon, Liberty, Union, Wakulla, and Washington counties, 
Florida; and in Baker, Calhoun, Coweta, Crawford, Crisp, Decatur, 
Dooly, Dougherty, Early, Fayette, Grady, Lee, Macon, Marion, 
Meriwether, Miller, Mitchell, Peach, Pike, Schley, Spalding, Sumter, 
Talbot, Taylor, Terrell, Thomas, Upson, Webster, and Worth counties, 
Georgia.

DATES: This rule becomes effective on December 17, 2007.

ADDRESSES: Comments and materials received, as well as supporting 
documentation used in the preparation of this final rule, will be 
available for public inspection, by appointment, during normal business 
hours, at the U.S. Fish and Wildlife Service, Panama City Ecological 
Services Office, 1601 Balboa Avenue, Panama City, FL 32405 (telephone 
850-769-0552). The final rule, economic analysis, and maps will also be 
available via the Internet at http://www.fws.gov/panamacity/.

FOR FURTHER INFORMATION CONTACT: Gail Carmody, Field Supervisor, Panama 
City Ecological Services Office, 1601 Balboa Avenue, Panama City, FL 
32405; telephone 850-769-0552; facsimile 850-763-2177. If you use a 
telecommunications device for the deaf (TDD), call the Federal 
Information Relay Service (FIRS) at 800-877-8339.

SUPPLEMENTARY INFORMATION:

Background

    It is our intent to discuss only those topics directly relevant to 
the designation of critical habitat in this final rule. For additional 
information on the seven mussels, refer to the final listing rule 
published in the Federal Register on March 16, 1998 (63 FR 12664), the 
final recovery plan that was approved September 19, 2003 (available 
from our Panama City, Florida Office or online at http://www.fws.gov/endangered/recovery/Index.html#plans), and the proposed critical 
habitat rule published in the Federal Register on June 6, 2006 (71 FR 
32746).
    The shinyrayed pocketbook was listed as federally endangered under 
the scientific name Lampsilis subangulata. The shinyrayed pocketbook 
and three other Lampsilis species are now assigned to the newly 
recognized genus Hamiota (Roe and Hartfield 2005, p. 1). The Service 
intends to implement the name change in a separate rulemaking. In 
November 2006, an Auburn University scientist working under contract 
for the Service identified eight mussels as shinyrayed pocketbooks that 
he found in a segment of Econfina Creek (M. Gangloff, personal 
communication November 3, 2006). This stream segment is within the area 
designated in this rule as critical habitat for the Gulf moccasinshell 
and oval pigtoe. If the identification is correct, this find represents 
the first record of the shinyrayed pocketbook in the Econfina Creek 
Basin, which was previously known only from the Apalachicola-
Chattahoochee-Flint (ACF) and Ochlockonee basins. The Service intends 
to conduct further surveys to confirm whether the species is in 
Econfina Creek and, if so, to estimate its range and abundance in the 
basin. In this rule, we do not designate Econfina Creek as critical 
habitat for the shinyrayed pocketbook.

Previous Federal Actions

    On March 15, 2004, the Center for Biological Diversity (Center) 
filed a lawsuit against the Department of the Interior and the Service 
(Civil Action No. 1:04 CV-0729-GET) challenging the failure to 
designate critical habitat for the seven mussels. In a settlement 
agreement dated August 31, 2004, the Service agreed to reevaluate the 
prudency of critical habitat for the seven mussels and, if prudent, 
submit a proposed designation of critical habitat to the Federal 
Register by May 30, 2006, and a final designation by May 30, 2007. On 
March 7, 2007, the court granted an extension and set the new final 
designation deadline for October 31, 2007.
    We published the proposed critical habitat rule for the seven 
mussels in the Federal Register on June 6, 2006 (71 FR 32746). We 
accepted public comments on the proposal for 60 days until August 7, 
2007. We completed a draft economic analysis (DEA) for the proposed 
designation on June 6, 2007, and published a notice of availability for 
this DEA in the Federal Register on June 21, 2007 (72 FR 34215). The 
public comment period for the DEA was open until August 6, 2007.
    For more information on previous Federal actions concerning the 
seven mussels, refer to the proposed critical habitat designation (71 
FR 32746, June 6, 2006) and our notice of availability of the draft 
economic analysis (72 FR 34215, June 21, 2007). This final rule 
complies with the settlement agreement.

Summary of Comments and Recommendations

    We requested written comments from the public on the proposed 
designation of critical habitat for the seven mussels in the proposed 
rule, and again in the subsequent notice of availability (72 FR 34215). 
On both occasions, we contacted appropriate Federal, State, and local 
agencies; scientific organizations; and other interested parties and 
invited them to comment on the proposed rule. Three public hearings 
were held during the second comment period on July 9, 2007, in 
Columbus, Georgia, July 10, 2007, in Albany, Georgia, and July 11, 
2007, in Tallahassee, Florida.
    During the first comment period that opened on June 6, 2006, and 
closed on August 7, 2006, we received comments from 30 entities that 
directly addressed the proposed critical habitat designation: one from 
a peer reviewer, 3 from Federal agencies, 16 from State and local 
governmental agencies, and 10 from organizations or individuals. We 
received 4 requests for a public hearing, all from entities in the 
LaGrange and Columbus, Georgia, area. During the second comment period 
that opened on June 21, 2007, and closed on August 6, 2007, including 
the three public hearings, we received comments from 25 entities that 
directly addressed the proposed critical habitat designation or the 
draft economic analysis: 4 from peer reviewers, 3 from Federal 
agencies, 7

[[Page 64287]]

from State and local governmental agencies, and 11 from organizations 
or individuals. Of the comments provided during both comment periods, 
six commenters supported the designation of critical habitat for the 
seven mussels and nine opposed the designation. Forty commenters 
provided suggestions or information, but did not indicate support or 
opposition to the critical habitat designation. We received comments 
that were grouped into 70 issues specifically relating to the proposed 
critical habitat designation for the seven mussels, and are addressed 
in the following summary and incorporated into the final rule as 
appropriate.

Peer Review

    In accordance with our policy published on July 1, 1994 (59 FR 
34270), we solicited expert opinions from seven knowledgeable 
individuals with scientific expertise that included familiarity with 
the species, the geographic region in which the species occurs, and 
conservation biology principles. We received responses from four of the 
peer reviewers. The peer reviewers generally concurred with our methods 
and conclusions, and provided additional information, clarifications, 
and suggestions to improve the final critical habitat rule. We address 
peer reviewer comments in the following summary and incorporate into 
the final rule as appropriate.
    We reviewed all comments received from the peer reviewers and the 
public for substantive issues and new information regarding critical 
habitat for the seven mussels, and address them in the following 
summary.

Peer Reviewer Comments

    (1) Comment: The Service stated in the proposed rule that ``Most of 
the tributary streams in the four basins that may support one or more 
of the seven species have never been surveyed.'' This seems to cast 
doubt on the adequacy of the data used to designate critical habitat. 
Most streams in this region that are large enough to support these 
species have been surveyed at least to some extent.
    Our Response: We acknowledge that a substantial fraction of the 
unsurveyed tributary streams in the region are probably not large 
enough to support populations of the seven mussels. However, the 
drainage area associated with the upstream-most location in most of the 
occupied watersheds is often quite small (e.g., less than about 5,000 
ha (20 mi\2\)), and we have no data for a majority of locations in the 
four basins that drain areas of this size. Regardless, we have 
considered all available survey data in our analysis for identifying 
critical habitat. We designated only where presence is confirmed by 
surveys.
    (2) Comment: The designation of critical habitat should consider 
whether re-establishing populations in streams where a species formerly 
occurred is necessary to fully recover the species.
    Our Response: The Act provides for designating areas that are 
unoccupied at the time of listing when such areas are essential for the 
conservation of a listed species. We listed the seven mussels based on 
a substantial decline in range and abundance and threats to their 
habitats. Our recovery plan (USFWS 2003:76-83) quantifies the amount of 
range expansion into formerly occupied areas that we believe is 
necessary to achieve recovery for the five species we listed as 
endangered. By delineating critical habitat units as the collective 
extent of occurrence of all seven listed species within a sub-basin, 
our proposed critical habitat included a stream length that met the 
recovery plan's geographic range recovery criteria for each of the five 
endangered species. We do not believe a substantial increase in extent 
of occurrence is either feasible or necessary for the recovery of the 
two threatened species, which have experienced a lesser decline in 
range than the five endangered species. The seven mussels historically 
occupied overlapping but also different portions of the eleven units, 
and it is not necessary for each species to occupy all suitable habitat 
within its designated critical habitat units to achieve recovery. We 
considered designating units for species that are entirely extirpated 
from those units but determined that doing so is not essential for 
their conservation.
    (3) Comment: Characterizing the stream substrates that are 
essential to the conservation of the seven mussels as composed of 
predominantly coarse materials is too simplistic and potentially 
misleading. Fine sediments (silts and clays) are a natural component of 
stream substrates in the coastal plain, including substrates used by 
the seven listed species. In this region, very coarse substrates are 
often associated with channel scouring and are devoid of mussels.
    Our Response: We agree that some amount (generally less than 50 
percent by dry weight) of fine sediment is a normal component of the 
substrate that is essential to the conservation of the seven mussels. 
Coarse sands without any silt or clay, for example, lack cohesiveness 
and do not appear to support many mussels, including the listed 
species. By emphasizing the adverse affects of excessive amounts of 
fine sediments, we may have implied that the seven mussels are 
altogether intolerant of fine sediments, which is not the case. 
Therefore, we have revised the substrate primary constituent element 
(PCE) and our discussion of substrate quality to acknowledge the 
appropriate role of fine sediments in substrate quality.
    (4) Comment: The proposed rule stated that the three other species 
reassigned from the genus Lampsilis to the newly recognized genus 
Hamiota are not federally listed, but two of these are: H. altilis and 
H. perovalis. The third, H. australis, is considered a candidate for 
protection under the Act.
    Our Response: The comment is correct. We erred in stating that the 
three other species are not federally listed, and we have revised the 
text of the final rule accordingly.
    (5) Comment: Because other portions of the Uchee Creek sub-basin 
besides those proposed for designation have supported the shinyrayed 
pocketbook and other listed species as recently as 1973, but have not 
been surveyed much or at all since then, the rule should designate all 
portions of this sub-basin below the Fall Line as critical habitat.
    Our Response: Riverine habitats are dynamic and subject to a 
variety of threats, which makes survey data about the presence of 
particular mussel species time-specific. It is not feasible to 
routinely survey the full range of the seven species, which 
collectively spans over 1,000 river miles. We chose post-1990 live 
occurrence records as a criterion for evidence that a site has 
supported recent occupancy because a great deal of our data comes from 
a range-wide status survey conducted in 1991 and 1992, shortly before 
the species were proposed for listing in 1994. Occurrence records from 
1973 do not meet the criterion we set for evidence of recent occupancy; 
therefore, we did not designate other portions of the Uchee Creek sub-
basin. Our method of identifying stream segments that meet the 
criterion of recent occupancy by one or more of the listed species and 
then delineating units as contiguous groups of these stream segments 
resulted in designating a total length of stream habitat meets our 
recovery plan's geographic range recovery criteria for each of the 
seven mussels (see response to Comment 2). Therefore, we 
believe that designating additional areas for which we do not have 
evidence of recent occupancy is not essential to their conservation. 
Listed species that may occur outside of designated critical habitat 
still receive protection under the

[[Page 64288]]

jeopardy standard of section 7 and the take prohibition of section 9 of 
the Act.
    (6) Comment: Because Sawhatchee and Kirkland creeks are separated 
by unsuitable habitat in an impounded section of the Chattahoochee 
River, these creeks should be designated as separate critical habitat 
units.
    Our Response: We have grouped Sawhatchee and Kirkland creeks in the 
same unit because they share two of three listed species in common and 
flow unimpeded by fish passage barriers into a common water body. Host 
fish, such as largemouth bass, could conceivably transport glochidia 
between these two streams.

Comments from States

    Section 4(i) of the Act states, ``the Secretary shall submit to the 
State agency a written justification for his failure to adopt 
regulations consistent with the agency's comments or petition.'' We 
address comments received from States regarding the proposal to 
designate critical habitat for the seven mussels below.
    (7) Comment: The designation is overly broad because it includes 
areas at high elevations within the lateral boundaries and areas 
between the upstream and downstream boundaries that do not support the 
mussels.
    Our Response: Our regulations allow the inclusive designation of 
occupied and unoccupied areas in proximity to each other that are each 
essential to the conservation of a species (50 CFR 424.12(d)). We agree 
that the adult seven mussels are seldom found at or near the ordinary 
high water marks in a stream, as this portion of the stream bed is 
inundated only during relatively high flows; however, we have 
determined that the entire stream channel between the ordinary high 
water marks is essential to their conservation as the larval life stage 
of these mussels while attached to a fish host or drifting in the 
current could ``occupy'' all habitats that the fish visits or the 
current takes them, including places at or near the ordinary high water 
marks during high water conditions. The location of suitable areas for 
mussel habitat is dependent on fluvial dynamics that occur mostly 
within the channel up to the ordinary high water marks. A stable stream 
bank that is laterally adjacent to but vertically above a mussel bed is 
essential to the viability of the mussel bed. Further, our regulations 
prescribe the use of reference points and lines as found on standard 
topographic maps for describing the boundaries of critical habitat (50 
CFR 424.12(c)). The ordinary high water marks as defined in the Corps' 
navigation regulations (33 CFR 329.11) roughly correspond to how river 
channels are represented on standard topographic maps. We agree also 
that the adult seven mussels are not found at all locations between the 
upstream and downstream boundaries given the unit descriptions. 
However, as with the lateral boundaries, we have determined that the 
entire stream channel between the upstream and downstream limits is 
essential to their conservation. Riverine habitats are dynamic, and 
locations that provide suitable conditions for mussels may shift over 
time between these upstream and downstream limits. Connectivity between 
the upstream and downstream limits provides for host fish movement, 
gametes transport, dispersal into newly suitable habitats, and food 
items transport. Therefore, we have kept these areas in the 
designation.
    (8) Comment: The designation is contrary to the Act because it 
includes areas that do not contain all of the physical and biological 
features that the Service determined are essential to the conservation 
of a listed species and may require special management (PCEs). For 
example, Unit 8 (Apalachicola River) includes the distributary Swift 
Slough, which has aggraded (filled with sediment) in recent years and 
no longer flows continuously.
    Our Response: Each of the 11 units designated as critical habitat 
contains all of the PCEs, and each stream segment listed in the unit 
descriptions contains one or more of the PCEs. Neither the Act nor our 
regulations require that all portions of a designated critical habitat 
unit contain all of the PCEs. Mobile animals typically satisfy various 
life history requirements by relying upon different habitat features in 
different portions of their range. While juveniles and adults of the 
seven mussels are relatively immobile animals, their glochidia (larvae) 
and host fish are not. Dispersal via fish hosts is how the species 
colonize new areas and is necessary to achieve recovery, although 
mussels are also sometimes moved into new areas by high-flow events. 
Mussels will best survive and reproduce in specific areas that 
consistently provide all of the PCEs, but do not necessarily persist 
permanently in any one area given the dynamic nature of the riverine 
environment. Interrupted flow due to the accumulation of sediment in 
the bed of Swift Slough has recently led to substantial mortality of 
listed mussels in this stream during periods of low-flow in the 
Apalachicola River. However, it does not follow that this or any 
particular area within a critical habitat unit that lacks all of the 
PCEs cannot be included in a critical habitat unit. Stream bed 
aggradation in Swift Slough signals the need for special management of 
the channel stability PCE in at least the Swift Slough portion of Unit 
8. While permanently flowing water, channel stability, etc., are 
features essential to the conservation of the seven mussels in each 
designated unit, we recognize that some portions of all 11 units have 
problems with at least one of the PCEs that may require special 
management or protections.
    (9) Comment: Florida Fish and Wildlife Conservation Commission 
personnel found shell material of the listed species in the Brushy 
Creek ``feeders'' (floodplain distributaries of the Apalachicola River 
that flow into Brushy Creek). The Service must determine whether the 
Brushy Creek feeders were likely occupied in 1998 (the time of 
listing), and if so, designate those streams if they otherwise qualify 
as critical habitat. Areas like the Brushy Creek feeders, currently 
unoccupied, should be designated anyway if they are essential for the 
conservation of the species. Areas like the Brushy Creek feeders are 
key to the recovery of mussels because they can act as nursery areas 
and provide for population expansion.
    Our Response: We relied upon post-1990 live occurrence records to 
provide evidence that areas were likely occupied at the time of 
listing, and we have no such evidence for the Brushy Creek feeders. 
Dead shells found recently in these distributaries, which receive flow 
directly from a part of the main channel of the Apalachicola River 
where listed species are known to occur, is not evidence that these 
streams support the listed species now or at the time of listing. It is 
more likely that the shells found in the Brushy Creek feeders were 
transported by currents from the main channel. We believe that areas 
for which we have no evidence of recent occupancy are not essential to 
the conservation of the listed mussels (see responses to comments 
2 and 5). We do not believe that the Brushy Creek 
feeders or other similar sites not included in this designation provide 
``nursery'' areas for mussels that are necessary for their recovery. 
The concept of a nursery area implies that mussels occupy one area as 
juveniles and another as adults. We have no evidence that such 
movements are occurring.

Public Comments

    (10) Comment: Line Creek in Unit 5 (Upper Flint River) does not 
provide suitable habitat for the listed mussels.

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    Our Response: Live listed species have been found in Line Creek 
downstream of its confluence with Whitewater Creek since 1990, and this 
segment contains PCEs. Consistent with our criteria for identifying 
critical habitat, we included this section of Line Creek in Unit 5.
    (11) Comment: Critical habitat designation will add costly delays 
to permitting a recreational reservoir on Tired Creek, which is 
upstream of designated habitat in Unit 9 (Upper Ochlockonee River).
    Our Response: The Service is designating critical habitat only 
where the mussels are currently present. Therefore, a Federal action 
that ``may affect'' critical habitat (and would trigger formal 
interagency consultation) would also result in a ``may affect'' 
determination for one or more mussel species (requiring formal 
consultation in and of itself). Our regulations prescribe specific 
timeframes in which to complete the formal consultation process with 
Federal agencies. These timeframes are the same whether or not critical 
habitat is designated and consulted upon during the required 
consultation process. Critical habitat designation does not create a 
separate consultation process. While the need to consult on adverse 
modification on critical habitat does not increase the statutorily 
allowed amount of time for consultation, it could increase the amount 
of effort that goes into the consultation process due to the different 
criteria for a jeopardy consultation versus an adverse modification 
consultation. Consideration of designated critical habitat in other 
environmental requirements (such as National Environmental Policy Act 
(42 U.S.C. 4321 et seq.)), similarly would not add to the length of 
time needed to comply with those requirements.
    (12) Comment: The proposed critical habitat for the seven mussels 
overlooks large areas of potential habitat and essentially disregards 
the Service's own recovery goals for these species. The Service should 
designate unoccupied areas containing PCEs within the historical range 
of the seven mussels.
    Our Response: Our June 6, 2006, proposed rule explained how we 
delineated the upstream and downstream limits of proposed critical 
habitat using the collective current distribution (post-1990 surveys) 
of all seven mussels and landscape features (e.g., tributary 
confluence, upstream extent of a reservoir) that indicated a 
significant change in aquatic habitat conditions (71 FR 32757-32758 
``Criteria Used To Identify Critical Habitat''). This approach resulted 
in 11 hydrologically and ecologically contiguous units, each of which 
is a collection of stream segments that flow unimpeded by fish passage 
barriers into a common reservoir or estuary. Moreover, as we noted in 
our response to peer-review comment 2, the total stream length 
delineated by these methods meets the geographic range recovery 
criteria in the recovery plan (Service 2003) for each of the five 
species listed as endangered.
    (13) Comment: Currently occupied habitat is insufficient for 
conservation of the seven mussels and, therefore, the critical habitat 
designation must include unoccupied habitat. Unsurveyed tributary 
creeks that likely support the seven mussels are excluded from the 
proposed critical habitat because the Service cannot confirm that 
mussels are present.
    Our Response: Our recovery plan for the seven mussels (Service 
2003) notes that re-introduction in presently unoccupied habitat is 
needed for the conservation of the five mussels listed as endangered, 
but not for the two threatened, species. The two threatened species, 
the Chipola slabshell and the purple bankclimber, each occupy well more 
than 50 percent of the historical range, which is the criterion we 
adopted for range expansion as a measure of recovery in the recovery 
plan. For the five endangered species, the stream length included in 
the designation meets the recovery plan's geographic range recovery 
criteria (see our responses to peer-review comment 2). 
Therefore, we believe the units designated provide a sufficient amount 
of habitat to support recovery, which precludes the need to designate 
unsurveyed tributaries that are not known to support the seven mussels. 
Nevertheless, we would recognize the contribution towards recovery of 
any populations found in previously unsurveyed streams in our periodic 
reviews of the conservation status of the seven species.
    (14) Comment: While permanently flowing water is essential to the 
seven mussels' survival, flowing water alone is insufficient for the 
conservation of these species. The final rule should adopt the Service-
Environmental Protection Agency (EPA) instream flow guidelines as the 
flow-related PCE.
    Our Response: We discussed in the June 6, 2006, proposed rule the 
role of natural variability in the flow regime to the structure, 
composition, and functioning of riverine biological communities. The 
Service-EPA flow guidelines are measures of flow variability that may 
serve as thresholds for ``may affect'' determinations for proposed 
Federal actions that would alter a flow regime (e.g., water 
withdrawals, dam operations). It was not practical or useful to compute 
the flow guidelines for the entire region that this designation spans, 
because the guidelines were designed as a tool for site- and project-
specific analysis. Further, the guidelines do not establish a general 
standard or ``bottom line'' for flow regime features that are essential 
to the conservation of listed species. Recognizing the many 
complexities involved in quantifying essential flow regime features for 
the seven mussels, we adopted a qualitative expression that applies 
throughout the range of the seven mussels and is clearly necessary for 
their recovery: ``permanently flowing water.''
    (15) Comment: Riparian buffers are essential to the conservation of 
the seven mussels and should be designated as primary constituent 
elements. If the final rule does not include intact riparian buffers as 
a primary constituent element, it should address riparian zones as a 
necessary element of related primary constituent elements.
    Our Response: Many factors operating outside the channel in the 
larger watershed affect streams and their inhabitants. Conditions in 
the riparian zone are among the most influential of these factors by 
virtue of immediate proximity to the stream channel, but the seven 
mussels do not occur in the riparian zone. A wide array of riparian 
buffer dimensions and vegetative characteristics are associated with 
the mussels. Activities within the riparian zone are among those that 
may adversely affect the PCEs, and likewise, some conservation actions 
to protect or enhance the PCEs may occur within the riparian zone. 
However, specific biological and physical features within the riparian 
zone are themselves not essential to the conservation of the seven 
mussels. We have used the ordinary high water marks of the channel as 
the lateral bounds for this designation (see also our response to 
comment 7), which encompasses all of the PCEs that we have 
defined for this designation.
    (16) Comment: One PCE recognizes fish hosts as necessary to 
``support the larval life stages of the seven mussels,'' but none 
address the habitat needs of the host fish species. The final critical 
habitat designation should be consistent with the rule for five 
Tennessee and Cumberland River mussels, which defined ``Fish hosts with 
adequate living, foraging, and spawning areas for them'' as a PCE, and 
also linked the ``flow regime'' and ``water quality'' PCEs

[[Page 64290]]

for the mussels with the needs of the host fish.
    Our Response: PCEs are essential physical and biological features 
that are found within critical habitat, the lateral boundaries of which 
we have delimited as the ordinary high water marks of the stream 
channel. The final critical habitat rule for five endangered mussels in 
the Tennessee and Cumberland River basins also used the same criteria 
(ordinary high water mark) to define the lateral boundaries of critical 
habitat. Therefore, while the wording of the PCEs might be different, 
the protection levels are the same since both use the ordinary high 
water mark to delineate the lateral boundaries of critical habitat.
    Several fish species that have been identified through laboratory 
tests as potential hosts for the seven mussels are known to spawn most 
successfully in floodplain habitats (e.g., largemouth bass), which 
occur outside the critical habitat boundaries. We agree that the 
habitat needs of host fish are important considerations in mussel 
conservation, but as with our response to Comment 15 regarding 
riparian buffers, we distinguish between PCEs and factors that may 
affect PCEs. The timely presence of appropriate host fish is the 
habitat feature that is essential for the survival and recovery of the 
mussels (i.e., the PCE itself), whereas the habitat requirements of the 
host fish are factors affecting that PCE.
    (17) Comment: The rule does not contain the summary of data on 
which the proposal is based, does not show the relationship of such 
data to the rule proposed, or provide citations to the mussel surveys 
relied upon, as required by the Service's regulations at 50 CFR 424.16.
    Our Response: Our summary of data supporting the PCEs is provided 
in the ``Primary Constituent Elements'' section. Our summary of data 
supporting the delineation of units is given in the ``Criteria Used To 
Identify Critical Habitat'' section. The mapping process involved an 
overlay of all available site-specific locality data for the seven 
mussels, which itself was not included in the published proposed rule 
and is not included in this final rule. The sources for all mussels 
survey data used in the mapping process are cited at the conclusion of 
each unit's description, where we list the species for which each unit 
is designated. A complete list of these and all references cited in 
this rulemaking is available upon request from the Panama City 
Ecological Services Office (see ADDRESSES).
    (18) Comment: The Service should not designate Swift Slough, which 
is part of Unit 8 (Apalachicola River), because it does not have the 
permanently flowing water PCE.
    Our Response: It is not necessary for all PCEs to be present in all 
portions of critical habitat at all times (see our response to Comment 
8). Habitat features change over time, and different portions 
of a unit will provide a different mix of the PCEs. At the time we 
initially drafted the proposed rule, we were not yet aware of sediment 
accumulation in Swift Slough that now results in its disconnection from 
the main channel of the Apalachicola River during low flows. Although 
mussels in Swift Slough have suffered considerable mortality since the 
summer of 2006, some animals persist from what was apparently a 
relatively large population. Swift Slough still meets the criteria we 
used to identify critical habitat; therefore, it is still included in 
the designation.
    (19) Comment: Water withdrawals are mentioned as causing changes in 
riverine habitats. This is a mis-statement of facts. If water is 
withdrawn and used and properly treated and returned to the basin of 
origin, it does not change the riverine habitat.
    Our Response: Most out-of-stream uses of water return less than 100 
percent of the water that is withdrawn, due to evaporation and other 
losses. In 2005, about half of the water withdrawn for municipal and 
industrial use in the Chattahoochee Basin upstream of West Point Dam 
was not returned to the river (Georgia Environmental Protection 
Division, unpublished data). Water withdrawals may affect aquatic 
habitat conditions and aquatic communities, depending on their timing 
and magnitude relative to stream flow. For example, fish assemblages 
were significantly less diverse downstream from relatively large water 
withdrawals and downstream from water supply reservoirs in the lower 
Piedmont region of Georgia (Freeman 2005).
    (20) Comment: The fact that the fecal coliform bacteria standard is 
violated in some reaches of the critical habitat has no effect on 
mussels. This standard is set to protect humans engaging in whole body 
contact with the water such as swimming.
    Our Response: We agree that fecal coliform bacteria standards are 
established to protect human health and violations of these standards 
do not necessarily indicate conditions that are harmful to mussels. 
However, it is possible that some of the bacteria and protozoans 
associated with wastewater discharges, which often includes fecal 
coliform bacteria, may adversely affect mussel reproduction (Goudreau 
et al. 1993:221). High fecal coliform levels may also derive from non-
point sources such as pastures and farms following rain events. Because 
the overland runoff that delivers fecal coliform bacteria from non-
point sources to streams may also carry pesticides, fertilizers, and 
other pollutants, elevated levels of other pollutants are often 
associated with high coliform counts.
    (21) Comment: The statements that ``Many pollutants in the ACF 
Basin originate from * * * and municipal waste water facilities'' in 
the proposed rule implies that waste water facilities are the source of 
pollutants that are harmful to the mussels. This is not correct if the 
waste water facilities are in compliance with National Pollutant 
Discharge Elimination System (NPDES) permits. All NPDES permits are 
required to ``not violate water quality standards,'' therefore the 
mussels would be protected. The fact that someone counted 137 municipal 
waste water facilities in the ACF basin is not relevant to the 
protection of the mussels assuming that these facilities all have NPDES 
permits and are in compliance. To arbitrarily assume that these 
facilities are not in compliance without factual data is wrong and is 
unscientific.
    Our Response: Municipal waste water treatment processes remove most 
but generally not 100 percent of all pollutants. Although treatment 
facilities and other point-source discharges may comply with NPDES 
permit conditions, the combined pollutant loading from all sources in a 
watershed may contribute to a total loading such that some reaches do 
not meet one or more water quality standards. When a stream is 
identified as impaired under the Clean Water Act (33 U.S.C. 1251 et 
seq.), the States initiate a process for developing total maximum daily 
load regulations under their delegated administration of the Clean 
Water Act. Our proposed rule indicated which critical habitat units 
contain stream segments on the impaired waters lists of the States. Our 
reference to the number of treatment facilities in the ACF Basin was 
part of describing the environmental setting of the critical habitat 
units. We did not assume or mean to imply that treatment facilities in 
the ACF were or were not in compliance with NPDES permits.
    (22) Comment: These two statements in the proposed rule contradict 
each other: (1) ``The ranges of several standard physical and chemical 
water quality parameters (such as temperature, DO, pH, conductivity) 
that define suitable habitat conditions for the seven mussels have not 
been specifically investigated;'' and (2) ``Various contaminants in 
point and non-point

[[Page 64291]]

source discharges can degrade water and substrate quality and adversely 
affect mussel populations.''
    Our Response: Our reference to ``several standard physical and 
chemical water quality parameters'' did not include contaminant 
concentrations. Parameters are those that aquatic biologists routinely 
measure with instruments in the field. Concentrations of contaminants 
that are known to adversely affect mussels, such as ammonia and heavy 
metals, are generally measured using water or sediment samples taken to 
a laboratory and not using instruments in the field. We have revised 
the rule language to avoid the apparent contradiction of these two 
statements.
    (23) Comment: There is no scientific basis given for implying that 
septic systems are responsible for mussel threats.
    Our Response: We include maintaining septic systems among the 
management considerations to deal with the threat of pollution to 
mussel habitats because inadequately maintained systems may contribute 
nutrients and other pollutants to ground water that can seep into 
surface water bodies. Nutrient loading can lead to algal blooms and low 
dissolved oxygen levels that adversely affect mussels, which we discuss 
under the water quality PCE.
    (24) Comment: The impacts associated with Whitewater Creek Park are 
minimal; therefore, the Service should exclude Macon County, Georgia, 
from the designation.
    Our Response: We do not include Whitewater Creek and Whitewater 
Creek Park in Macon County in designated critical habitat for the seven 
mussels. However, we do include a different Whitewater Creek in Fayette 
County, Georgia. We also include the main channel of the Flint River 
and Hogcrawl Creek in Macon County as parts of Unit 5 (Upper Flint 
River).
    (25) Comment: Critical habitat for the seven mussels is not 
determinable because the Service has insufficient data. Most of the 
mussel distributional records are from the early 1990s and further 
studies are needed to define suitable habitat conditions for the seven 
mussels.
    Our Response: Much of the survey data upon which we relied dates 
from the early 1990s, but this does not in and of itself render 
critical habitat undeterminable. The Act contemplates critical habitat 
designation ``at the time it [the species] is listed'' (Sect. 
3(5)(A)(i)); therefore, we must necessarily rely on distributional data 
from the time of listing as well as more recent data. It happens that 
most of our records are from the early 1990s because the most 
comprehensive survey effort in the range of the seven mussels 
immediately preceded the listing proposal, which was published on 
August 3, 1994 (59 FR 39524). Due to a moratorium on listing actions 
declared by Congress shortly thereafter, we did not publish a final 
rule until March 16, 1998 (63 FR 12664). We agree that further studies 
are needed to more quantitatively define the seven mussels habitat 
requirements; however, the best available information regarding those 
requirements is sufficient to define qualitative but workable and 
meaningful PCEs. Further, the PCEs adopted in this rule are generally 
consistent with those adopted in previous rules designating critical 
habitat for freshwater mussels.
    (26) Comment: Contrary to the Service's regulations at 50 CFR 
424.12(c), the Service has used an imprecise ephemeral boundary, the 
ordinary high water marks, to define the lateral extent of the proposed 
critical habitat area.
    Our Response: Although the ordinary high water marks of a stream 
may shift location over time, they do not disappear. The intent of the 
regulation cited is avoiding reliance in critical habitat descriptions 
on ephemeral features, i.e., features that last a relatively short 
time. We agree that the ordinary high water marks are not a precise or 
a fixed set of coordinates over time, but they are an appropriate 
descriptor for dynamic riverine habitat. A fixed set of coordinates 
that would fully encompass the areas we have determined are essential 
would either become quickly obsolete through natural or human-induced 
lateral channel migration, or would delineate an overly broad area by 
including a fair amount of terrestrial habitat.
    (27) Comment: The analysis of what activities may affect the 
proposed critical habitat designation set forth in the proposed rule is 
both misleading and incomplete. As a result some persons may conclude 
by default that any and all activities affecting portions of the 
critical habitat, however minimally, will require consultation under 
section 7 of the Act.
    Our Response: The section 7 consultation process applies only to 
Federal actions. Federal agencies are responsible for determining 
whether their actions may affect listed species or designated critical 
habitats. Action for which the action agency makes ``no effect'' 
determinations does not require further consultation with the Service. 
Service concurrence is required for other determinations, and the 
Service routinely assists Federal agencies in defining classes of 
actions that may comply with section 7 through informal consultation. 
The formal consultation process, which requires the Service to prepare 
a biological opinion, applies to those actions that Federal agencies 
determine may adversely affect the listed species or designated 
habitat. We do not expect the designation of critical habitat to 
appreciably increase either the number of actions per year to which the 
consultation process applies or for which formal consultation is 
required.
    (28) Comment: The proposed rule provides no guidance for 
determining which features of the flow regime are important to mussels 
and their host fishes. Therefore, it is impossible to determine whether 
the Service has actually made a determination that certain activities 
presumptively ``may affect'' critical habitat. The Service-United 
States Environmental Protection Agency instream flow guidelines 
referenced in the proposed rule do not provide a sufficient or 
appropriate basis for evaluating proposed activities, because the 
guidelines are not self-explanatory and are not obviously relevant to 
the seven mussels.
    Our Response: The measures of flow magnitude, duration, frequency, 
and seasonality that are included in the Service-USEPA instream flow 
guidelines (USFWS and USEPA 1999) may be used to determine whether 
Federal actions may affect listed species. This is the express purpose 
of the guidelines, which is relevant to the seven mussels. Application 
of the guidelines for this purpose is a site-specific and data-
intensive process that involves computing long-term flow statistics for 
a project area with and without a proposed Federal action. Actions that 
would alter the flow parameters included in the guidelines, e.g., 
increase the maximum number of days per year that flow is less than 25 
percent of average annual discharge, may adversely affect listed 
species and require formal consultation. The process for computing and 
applying the guidelines is explained in the guidelines document. 
However, to provide more information about the guidelines in this 
designation, we have added a listing of the flow regime features that 
are included in the guidelines to the flow regime PCE discussion.
    (29) Comment: The Service should follow the procedures prescribed 
by the National Environmental Policy Act (NEPA) as part of this 
rulemaking.
    Our Response: It is our position that, outside the jurisdiction of 
the Tenth Federal Judicial Circuit, we are not required to prepare 
environmental analyses as defined by NEPA in

[[Page 64292]]

connection with designating critical habitat under the Endangered 
Species Act of 1973, as amended (see Required Determinations--NEPA).
    (30) Comment: The Service fails to note that impoundments are very 
efficient in removing sediment, with large southeastern reservoirs 
trapping 80-90% of the incoming sediment.
    Our Response: In the ``Summary of Threats to Surviving 
Populations'' section, we note how impoundments block the natural 
downstream movement of sediment, which commonly leads to channel 
degradation in the tailwaters of dams built in alluvial rivers 
(Williams and Wolman 1984, p. 14; Lignon et al. 1995, p. 187). Rather 
than providing a net benefit to mussels by trapping excessive sediment 
loads, dams may largely remove native riverine mussels from tailwater 
areas through channel scouring processes as well as from stream 
segments inundated by reservoirs. For example, the fat threeridge was 
formerly abundant but is now rare in the upstream reaches of the 
Apalachicola River, most likely due to substantial channel incision 
resulting from the construction of Jim Woodruff Lock and Dam.
    (31) Comment: The Service fails to note that impoundments with 
large storage capacity may increase base flows downstream during 
periods of drought. Increased minimum flow may benefit downstream 
mussel habitat. The storage capacity of large reservoirs may also 
reduce the impact of flood flows that historically would result in 
scour and bank erosion.
    Our Response: The seven mussels evolved under natural flow regimes 
that include droughts and floods. Human consumptive uses of water may 
decrease stream flow below naturally occurring levels, and releases 
from reservoirs may offset the impact of this depletion, depending on 
how reservoirs are operated. However, reservoirs generally reduce the 
average annual discharge of a river by increasing evaporative losses 
via a greater water surface area. Increasing river flow with releases 
from reservoir storage necessarily requires decreasing river flow at 
other times to replenish storage, which may adversely affect mussels. 
However, we are aware of no evidence that the magnitude, frequency, 
duration, or timing of flood flows has been appreciably altered by dams 
in the stream reaches that are included in this critical habitat 
designation.
    (32) Comment: Relative to the application of the jeopardy and 
adverse modification standards, the Service provides no evidence that 
the operation of dams would alter flows in a manner that would destroy 
or adversely modify critical habitat.
    Our Response: Federal actions that would destroy or adversely 
modify critical habitat are those that alter the PCEs to an extent that 
the conservation value of the habitat is appreciably reduced. We 
included dam operations as an activity that could, but does not 
necessarily, significantly alter flow regimes. Determining whether dam 
operations may adversely affect critical habitat is a site- and 
project-specific analysis. The Service-USEPA instream flow guidelines 
(USFWS and USEPA 1999) are an appropriate tool for making such 
determinations (see comment 28). It is not necessary to 
establish that an action, such as dam operations, is certain to 
adversely modify critical habitat in order to name it in our 
designation among the actions that could do so.
    (33) Comment: The Service is required to list the specific PCEs for 
each individual mussel in each unit designated as critical habitat. The 
Service does not provide evidence, explanations, or citations detailing 
the requirements of each species relative to each of the PCEs.
    Our Response: The Act and our regulations do not prohibit multi-
species critical habitat designation rules, and the Service has 
previously issued several multi-species critical habitat rules in which 
a common set of PCEs applies to more than one species (for example, 
July 17, 2007, final rule for Peck's Cave amphipod, Comal Springs 
dryopid beetle, and Comal Springs riffle beetle, 72 FR 39248). We 
acknowledge that each of the seven mussels has a unique life history 
and niche in the riverine environment, but that these are similar 
enough to describe PCEs for the seven mussels as a group. Although the 
PCEs are the same for all seven mussels, the mix of units designated as 
critical habitat for each species is unique, reflecting differences in 
their spatial distribution.
    (34) Comment: The rule should address the threat of dam removal to 
the mussels and include dam removal as an action that could appreciably 
alter the channel stability and flow PCEs.
    Our Response: The Service is unaware of dam removal proposals 
within the areas we are designating as critical habitat. Dam removal 
could conceivably initiate channel instability; however, the most 
likely motivation for a dam removal project would be restoration of 
free-flowing conditions that were previously impaired by impoundment. 
This is the motivation for the proposed removal of the Eagle-Phenix Dam 
and the City Mills Dam, which would restore a total of approximately 
2.3 miles of the biologically significant Fall Line shoal habitat in 
the Chattahoochee River. Although this area has not been designated as 
critical habitat, it is within the historical range of some of the 
seven mussels. Eagle-Phenix and City Mills dams do not store an 
appreciable volume of water, and removing these dams would not affect 
downstream flow regimes.
    (35) Comment: The proposed rule cites no evidence to support the 
assertion that the seven mussels are not found in impoundments.
    Our Response: Brim Box and Williams (2000) surveyed 324 sites in 
the ACF, including several sites within several impoundments, including 
Lake Seminole, Lake Walter F. George, and West Point Lake. They found 
no live individuals of the listed species within any of the 
impoundments.

Economic Analysis--Policy Issues

    (36) Comment: Multiple commenters requested the economic analysis 
consider those impacts due solely to the designation of critical 
habitat for the seven mussels.
    Our Response: Appendix B of the Final Economic Analysis (FEA) 
estimates the potential incremental impacts of critical habitat 
designation for the seven mussels. It does so by attempting to isolate 
those direct and indirect impacts that are expected to be triggered 
specifically by the critical habitat designation. The incremental 
conservation efforts and associated impacts included in Appendix B 
would not be expected to occur absent the designation of critical 
habitat for the seven mussels. Total present value potential 
incremental impacts are estimated to be $501,000. All other impacts 
quantified in the FEA are considered baseline impacts and are not 
expected to be affected by the critical habitat designation.
    (37) Comment: Several commenters stated the Initial Regulatory 
Flexibility Analysis does not adequately estimate the potential impacts 
to small entities.
    Our Response: Appendix C in the FEA has been revised and now 
considers the extent to which the incremental impacts analysis 
described in Appendix B could be borne by small entities and the energy 
industry as opposed to fully co-extensive impacts quantified in 
Sections 3 though 6. The incremental impacts of the rulemaking are 
considered most relevant for the small business and energy impacts 
analyses as they are expected to stem from the critical habitat 
designation, and are therefore not expected to occur in the case that 
critical habitat is not

[[Page 64293]]

designated for the seven mussels. The analysis concludes that one 
hydropower operator and 10 deadhead logging companies may be affected 
by critical habitat designation as proposed.
    (38) Comment: One commenter states that the Draft Economic Analysis 
(DEA) explains that no estimates of minimum flow have been developed by 
the Service or any other entity. In order to assess ultimate hydropower 
impacts, these estimates must be made, and included in the economic 
analysis.
    Our Response: In the absence of information on minimum flow levels 
for the seven mussels the FEA relies on the best available information 
solicited from resource managers on the likely efforts that would be 
needed to protect the seven mussels to estimate the potential future 
impacts associated with conservation efforts in areas proposed for 
designation.
    (39) Comment: One commenter indicates that the impacts of 
implementing the U.S. Army Corps of Engineers (USACE) Modified Interim 
Operating Plan (Modified IOP) need to be distributed between gulf 
sturgeon and mussels, as it considers both.
    Our Response: The Modified IOP is intended to protect the mussels, 
their host fish, and gulf sturgeon. Specific information on which 
species generated which conservation efforts in the plan is not 
available. This analysis therefore quantifies the full impact of the 
plan as co-extensive with seven mussels conservation. Appendix B in the 
Final Economic Analysis (FEA) estimates the incremental impacts 
associated solely with the designation of critical habitat for the 
seven mussels; impacts associated with the Modified IOP are not 
considered to be incrementally due to critical habitat.
    (40) Comment: Several commenters state that potential benefits of 
critical habitat designation should be quantified.
    Our Response: The economic analysis conducted for this rule points 
out that there are some potential benefits of critical habitat 
designation. However, it is difficult to develop credible estimates of 
such values, as they are not readily observed through typical market 
transactions and can only be inferred through advanced, tailor-made 
studies that are time consuming and expensive to conduct. We currently 
lack both the budget and time needed to conduct such research before 
meeting our court-ordered final rule deadline. The economic analysis is 
done primarily to provide decisionmakers with information about 
potential exclusions from the rule. Given the impracticality of 
conducting this additional analysis we do not believe it is necessary 
to quantify the positive consequences of this rule in order to weigh 
the benefits of including versus excluding areas from the rule. The 
Congress has already determined that the benefits of species recovery 
are high. Therefore, we do not require quantification of how high in 
order to make a sound decision.

Economic Analysis--Economic Issues

    (41) Comment: One commenter states that the DEA did not desegregate 
impacts in Unit 8, Apalachicola River to focus on Swift Slough, River 
Styx, and Kennedy Slough.
    Our Response: The water management adopted per Reasonable and 
Prudent Measure (RPM) 3 of the Biological Opinion for USACE operations 
at Jim Woodruff Dam raised the minimum flow in the Apalachicola River 
to 6,500 cfs when composite storage (all reservoirs combined) is above 
zone 3, at which time it reverts to 5,000 cfs. At this time the Service 
does not anticipate maintaining higher minimum flows for Swift Slough, 
River Styx, and Kennedy Slough than already considered in the Modified 
IOP. Therefore, the FEA does not estimate any additional impacts 
associated with these tributaries.
    (42) Comment: One stakeholder commented that the Modified IOP is an 
interim plan and can change soon. Another commenter noted that the 
USACE 2007 Environmental Assessment quoted in Section 4 of the report 
has not been vetted through an official process, and that a May 16, 
2007, letter from USACE to the Service indicates that changes to 
Modified IOP operations are ongoing, and make USACE statements suspect 
as they are subject to change.
    Our Response: The USACE currently manages its operations in 
accordance with the 1989 Draft Water Control Plan for the Apalachicola-
Chattahoochee-Flint (ACF) reservoir system and makes minor adjustments 
as necessary to accommodate changes in current needs. Current 
management under the Draft Water Control Plan is set out in the 
Modified IOP. The Modified IOP reflects how the USACE is regulating the 
minimum releases and maximum fall rates at Jim Woodruff Dam. In 2007, 
the USACE completed an Environmental Assessment of the Modified IOP. 
Finalization of the Draft Water Control Plan depends on the result of 
ongoing litigation filed by the State of Alabama in 1990. Although it 
is expected that the Water Control Plan, and the Modified IOP will be 
updated subsequent to the resolution of the litigation process, 
information is not available to identify what changes to management may 
occur. The FEA therefore applies the best information available, i.e., 
the Modified IOP and Draft Water Control Plan, regarding water 
management and acknowledges the uncertainty regarding this activity in 
the future.
    (43) Comment: A few commenters stated that the input parameters 
that the USACE uses for its HEC-5 hydrological model differ from the 
parameters used by Georgia and Florida and that the results presented 
in the DEA could change if these different input parameters are 
included in the analysis.
    Our Response: To address the comment, the FEA includes additional 
results from Georgia Environmental and Protection Division's (EPD) 
analysis of the Modified IOP. Section 2 has been updated with a 
detailed discussion of how the USACE's assessment of the depletion of 
water storage in the major dams on the Chattahoochee River is 
consistently less than Georgia EPD's assessment. Several exhibits have 
been added that compare the two agencies' interpretations of the impact 
of the Modified IOP on reservoir storage capacity. The comparisons are 
made for both year 2000 and year 2030 water demand levels, and for 
normal and drought conditions. Section 3 of the FEA was revised to 
include these new estimates. Using this new information the present 
value of potential economic impacts to recreationists associated with 
conservation efforts for the seven mussels in Unit 8, Apalachicola 
River, increased to be between $27.7 million and $54.1 million 
(discounted at three percent).
    (44) Comment: A commenter stated that the Service's use of instream 
flow guidelines in Section 2 of the DEA was not mentioned in the 
September 2006 Biological Opinion on USACE's IOP for Jim Woodruff Dam.
    Our Response: Instream flow guidelines discussed in the DEA are as 
described by the Service in the June 6, 2006, proposed rule for the 
critical habitat designation of the seven mussels, not the 2006 
biological opinion. The EPA-USFWS guidelines are referenced in Section 
2 of the FEA.
    (45) Comment: One commenter stated that the assumption that 
municipal and industrial impacts may result due to USACE's water 
management operations of the ACF system is directly contradicted by 
USACE language, which indicates that lake levels will not fall below 
water intake structures because of operations under the Modified IOP.
    Our Response: The USACE analysis of the impacts of the Modified IOP 
impacts models year 2000 water demand; it does not assess the impact of 
the Modified IOP for year 2030 water demands.

[[Page 64294]]

However, Georgia EPD provides simulated lake levels for both year 2000 
and year 2030 water demand levels. Section 2 of the FEA, discusses how 
model simulations conducted by the Georgia EPD suggest that lake levels 
may go below water intake structures in the future, especially under 
year 2030 water demand levels. This can happen even without the 
modifications introduced by the Modified IOP. Thus, in the case that 
sustained drought conditions exist in the future, the Modified IOP can 
potentially further decrease lake levels.

Potential Economic Impacts Related to Changes in Water Use and 
Management

    (46) Comment: A few commenters have expressed reservations about 
attributing the impact of the Modified IOP on municipal and industrial 
water supply and recreation to the critical habitat of the three 
mussels found in the Apalachicola River complex because the Modified 
IOP predates the designation.
    Our Response: The impact of the Modified IOP on municipal and 
industrial water supply is not quantified in the DEA. For recreation 
related impacts, which are quantified in Section 3, the FEA quantifies 
the fully co-extensive impacts of any Federal, State, or local 
regulations or guidelines that may benefit the seven mussels in the 
proposed critical habitat area. Appendix B of the FEA acknowledges that 
implementing the Modified IOP is not an incremental impact attributable 
to the proposed rule.
    (47) Comment: Several commenters have indicated that water quality 
could become a concern at lower lake levels.
    Our Response: Section 2 of the FEA notes these concerns based on 
Georgia EPD's analysis of how declining lake levels during sustained 
periods of drought could expose the water intake structures of several 
local governments in Georgia. Additionally, Georgia EPD concludes that 
the Modified IOP leads to an increase in the number of days that the 
desired flow for wastewater assimilation below the Columbus gage will 
not be met. Section 5 discusses other potential water quality-related 
impacts. These potential water quality impacts are associated with 
Modified IOP implementation and are not expected to result from the 
critical habitat designation as proposed.
    (48) Comment: One commenter mentioned that there is no mechanism 
for the Flint River Drought Prevention Act (FRDPA) to restrict 
agricultural uses based solely on impacts to protected mussels.
    Our Response: The DEA does not make assumptions or recommendations 
regarding how changes in irrigated agricultural use will occur, or who 
will bear the cost of changes in water management and use. As discussed 
in Section 6 of the FEA, the Georgia Department of Natural Resources, 
Wildlife Resources Division plans to develop a Habitat Conservation 
Plan (HCP) to address agriculture related impacts to seven mussels 
conservation in the Lower Flint River Basin. The HCP is expected to 
reduce irrigation in the Lower Flint River Basin during severe drought. 
In addition, there were reverse auctions conducted associated with the 
Flint River Drought Protection Act (2000), during which irrigation 
rights were purchased from farmers, during the drought periods in 2001 
and 2002.
    (49) Comment: Several commenters indicate that information 
necessary to quantify municipal and industrial impacts is ``readily 
available and should have been collected and analyzed as part of the 
economic analysis.''
    Our Response: Section 3 of the FEA explains that it was unable to 
estimate the impacts of mussel conservation efforts on municipal and 
industrial water supply because of numerous uncertainties in the 
relationship between water management under the Modified IOP and water 
supply. To quantify these impacts, the following information is needed: 
(a) The relationship between lower lake levels due to the Modified IOP 
and the risk that municipal water use will be restricted in some way 
(i.e., the marginal increase in risk of droughts being declared); (b) 
the amount of water lost from each sector (e.g., industry) within 
Chattahoochee River Basin municipalities due to drought restrictions 
and quantification of the effect of timing restrictions on water 
availability; and (c) data to estimate the value of less transparent 
water uses (e.g., lawn watering). These data are currently not 
available.
    (50) Comment: One commenter indicated that the DEA underestimates 
the economic impacts associated with critical habitat designation at 
West Point Lake, citing preliminary results from an ongoing study. The 
FEA indicates that impacts associated with low water levels (i.e., 
water levels below top pool elevations) not specifically due to the 
Modified IOP may be as high as $90 million. The commenter states the 
following: (a) Recreation visits are underestimated, (b) the DEA did 
not consider estimates of rapid growth associated with the greater 
LaGrange, Georgia area, (c) property value changes in response to 
changes in lake level are not analyzed, and (d) the estimate of average 
boating expenditures within 30 miles ($68 per trip) is low.
    Our Response: The West Point Lake study described by this commenter 
was commissioned to investigate the economic impact of low water 
levels, which are only in part influenced by the mussel conservation 
efforts. In response to the specific points: (a, b) A new source of 
data on visitation to West Point Lake has been identified and 
incorporated into the FEA (increasing the present value estimate of 
potential future impacts to recreationists at West Point Lake to 
between $11.0 million and $16.5 million, discounted at three percent). 
(c) Estimating property value impacts would require a study that has: 
(i) Estimated how property values in the region (ideally, at West Point 
Lake) have changed in response to changing lake levels and (ii) is 
capable of characterizing the marginal change in property values of 
changes in lake levels. Such a study has not been identified. (d) 
Average boating expenditures are used in the regional impact analysis. 
The within 30-mile expenditure value of $68 per trip is the best 
estimate currently available. The $95 estimate includes nationwide 
travel expenditures to Lake Lanier and therefore cannot be used to 
estimate regional impacts.
    (51) Comment: Several commenters indicate that McMahon et al. 2004 
is inappropriate to use in the DEA to estimate potential impacts of 
lower lake levels on recreation. Specifically, (a) McMahon et al. use 
1995 boater visitation data that is outdated; and (b) omitting impacts 
on non-boaters would result in a significant underestimate of impacts.
    Our Response: An extensive literature review of the recreation 
literature (refer to Appendix F of the FEA) was conducted and did not 
identify any other studies that were transferable to the situation at 
Lake Lanier. McMahon et al. was selected for a few reasons: (a) The 
robustness of the method (Random Utility Model), (b) the geographic 
appropriateness of the analysis, and (c) the transferability of the 
results (elasticity measures). This study provided the best available 
information for this particular analysis. Additionally, data are not 
currently available on use levels to incorporate non-boater effects in 
the FEA. The commenter does not identify any potentially applicable 
studies or data.
    (52) Comment: Several commenters indicate that recreational damages 
are more sensitive to changes in shoreline than changes in lake surface 
area, and that it is therefore not appropriate to use lake levels as a 
proxy for changes in

[[Page 64295]]

recreation. Additionally, the commenters indicate that the shapes of 
the different lakes vary considerably, so that the draw down of West 
Point Lake exposes far more shoreline than Lake Lanier, creating 
greater economic impacts to recreational and property interests on the 
shore.
    Our Response: Information at this level of specificity is not 
currently available to relate water withdrawal to shoreline changes. 
Section 3 of the FEA acknowledges this limitation. However, some 
aspects of lake shape are implicitly incorporated into the modeled 
relationship between drawdown and surface levels; for example, a steep-
walled lake will have very little change in surface area as water 
levels fall, whereas a lake with relatively flat shorelines will 
experience the opposite effect, and thus have a greater level of 
estimated impacts to recreation.
    (53) Comment: One commenter indicated that the DEA models 
willingness to accept rather than willingness to pay for recreation. 
Because willingness to accept is generally higher than willingness to 
pay, the analysis overestimates impacts.
    Our Response: This comment misinterprets the DEA. The analysis 
models the compensating variation associated with these trips, which is 
a measure similar to consumer surplus. These values were developed in 
the context of random utility models, created from a travel cost 
framework. Travel expenditures are most reflective of willingness to 
pay rather than willingness to accept values.
    (54) Comment: Several commenters suggest that the DEA does not 
consider the lake elevations corresponding to water supply intakes and 
boat ramps in the DEA's estimation of recreational costs; therefore, 
costs are underestimated.
    Our Response: Declines in lake levels may affect some water intakes 
and boat ramps. As discussed in Section 3 of the FEA, impacts may vary 
as water levels reach boat ramps and docks, but sufficient information 
on the lake levels at which boat ramps and docks are stranded and 
recreationists responses to these changes is not available to estimate 
these potential impacts.
    (55) Comment: Several stakeholders express concerns that water may 
not be removed from low value uses first, and that the FEA should 
provide the institutional mechanisms that will drive this process. As 
an example, a stakeholder mentions that agricultural uses in other 
portions of the ACF basin will continue unabated, even during drought.
    Our Response: Because of the uncertainty regarding the uses most 
likely to be affected by changes in water allocation this discussion 
has been removed from the FEA.
    (56) Comment: One stakeholder expresses concerns that insufficient 
attention is paid to the adaptations that are available to minimize 
withdrawals for agriculture, and that the DEA therefore overestimates 
impacts.
    Our Response: The DEA may overstate agricultural impacts due to 
insufficient information on the adaptive ability of irrigators. As 
discussed in the caveats of Section 3 of the FEA, various adaptive 
management strategies may be available that could reduce estimated 
economic impacts on agriculture. Specific information on these 
strategies and their applicability is unavailable.
    (57) Comment: One commenter indicates that Exhibit 3-16 in the DEA 
treats expenditures foregone as an element of regional economic loss 
when, in fact, it is the producer surplus foregone that is the basis of 
the impact on the region.
    Our Response: The DEA uses a software program called IMPLAN to 
estimate the regional economic effects of reductions in economic 
activity in agriculture and recreation-related industries associated 
with seven mussels conservation efforts. As discussed in Section 3 of 
the FEA, the input to this program is expenditures rather than producer 
surplus, as the costs to some suppliers are revenues to others further 
up the supply chain. Depending on the characteristics of the region 
(i.e., imports versus exports), these costs may therefore also accrue 
as revenues to the region. Regional and sectoral multipliers in IMPLAN 
account for this effect.
    (58) Comment: One commenter indicates that the fixed cost of 
irrigation equipment should not be included an element of damage; it is 
a sunk cost and is not imposed by water use restrictions and cannot be 
avoided in the event of restrictions.
    Our Response: It is appropriate to include a portion of fixed costs 
in the agricultural impact estimates. Unlike variable costs, fixed 
costs are often unrecoverable. Under these circumstances, they are an 
element of damage: although fixed costs themselves are not imposed by 
water use restrictions, the inability to recover these sunk costs of 
purchasing irrigation equipment is caused by the imposition of these 
water use restrictions.
    (59) Comment: One commenter indicates that if voluntary auctions 
are held where irrigators are paid to temporarily dryland farm certain 
acres, then the local and regional economic impacts identified in the 
analysis may be partly or wholly offset.
    Our Response: As indicated in Section 3 of the FEA, the FEA makes 
no assumptions about how the reductions in agricultural water 
withdrawals will occur, nor who will bear these costs. In other words, 
the economic analysis only uses the voluntary auctions as evidence that 
institutional mechanisms exist to provide water for mussels' 
conservation.
    (60) Comment: Several commenters indicate that the DEA should 
assume a more frequent severe drought interval based on the more recent 
rainfall record.
    Our Response: The one in 20-year drought interval is based on 
information provided by the Georgia State Climatologist for pre-2000 
conditions. The frequency of droughts may have increased from this 
estimate, however, as no study has forecasted drought frequency for 
future years, the analysis uses the pre-2000 information. If updated 
frequencies were made available that indicated a shorter drought 
interval, forecasted impacts in the Lower Flint Basin would increase 
(i.e., if drought frequency increased from one in 20 years to one in 10 
years, impacts would increase roughly by a factor of two).
    (61) Comment: One commenter indicated that more appropriate data on 
agricultural acreages and crop yields during dry years are readily 
available and should be incorporated into the DEA.
    Our Response: New information on crop acreages and crop yields has 
been incorporated into the FEA, increasing the present value of 
agricultural impacts over 20 years from $2.16 million to $29.0 million 
(discounted at three percent).
    (62) Comment: One commenter suggests using gross revenues instead 
of net revenues for the irrigated versus dryland impacts to 
agriculture.
    Our Response: For individual farmers, the FEA assumes that 
conversion to dryland farming will reduce revenues, but will also 
reduce costs. Accordingly, the agricultural subsection of Section 3 in 
the FEA estimates impacts on a net revenue, rather than gross revenue 
basis. Later in Section 3, a regional economic impact subsection is 
presented, where impacts to the region are estimated based on lost 
gross revenues.
    (63) Comment: One commenter indicates that a consistent measurement 
standard should be employed to assess economic impacts, and that the 
study does not indicate the measurement standard that is being used. 
Specifically, it is not clear if the DEA is presenting marginal values 
or average values. The

[[Page 64296]]

commenter states that additionally the DEA appears to do an 
inconsistent job of forecasting future economic conditions. In some 
cases future demands are established, while in other cases they are 
ignored.
    Our Response: Section 1 of the FEA describes the framework for the 
analysis including measurement standards. As discussed in Section 1, 
forecasting is conducted where data are available. In many instances, 
forecasting was not possible (e.g., forecasting agricultural water 
demands) given data constraints.

Potential Economic Impacts to Hydropower, Water Supply, and Other 
Impoundment Projects

    (64) Comment: Several commenters state that potential impacts to 
hydropower are understated and should be quantified. Specific concerns 
relate to the lack of information on the difference in value between 
peaking and non-peaking power, and that any change in the capability to 
generate power may result in impacts.
    Our Response: Quantification and monetization of the potential 
impacts to hydropower are not possible absent information on the 
potential change in operations and associated timing of releases that 
may result from mussel conservation efforts. Specifically, without 
information regarding how operations under the Modified IOP for the 
listed mussels in the Apalachicola River would affect timing of 
hydropower generation, potential impacts to hydropower generation 
cannot be quantified. As discussed in Section 4 of the FEA, the value 
of power fluctuates on an hourly basis while the data available for 
this analysis describe power production on a monthly basis. If releases 
for hydropower cannot be made, replacement power must be purchased to 
meet demand. While all these potential impacts are described 
qualitatively, the USACE states in its public comment that the 
allowable hydropower schedule remains unchanged from the existing 
hydropower operations prior to the Modified IOP. Potential impacts to 
hydropower are therefore uncertain.
    (65) Comment: Two commenters state that the DEA inaccurately 
ascribes value to the hydropower generated at USACE projects from 
information provided by Southeastern Power Administration (SEPA).
    Our Response: Based on follow-up communication with SEPA, these 
dollar amounts have been removed from the FEA. They represent a 
composite of various expenses and cost obligations, and are not 
indicative of the relative importance of the projects. The relative 
value or revenues associated with individual projects cannot be 
disaggregated from the full system from which hydropower is marketed.
    (66) Comment: One commenter states that impacts associated with 
relicensing the Bartlett's Ferry and other non-Federal FERC-licensed 
projects on the Chattahoochee River should be included.
    Our Response: The Bartlett's Ferry Project is on the Chattahoochee 
River. Its current FERC license will expire in 2014. The projects for 
which mussel conservation efforts (surveys and monitoring) associated 
with FERC relicensing are quantified in Section 4 of the DEA are on the 
Flint River bordering critical habitat, where listed mussels are 
present. No information is available that suggests that projects 
undergoing FERC relicensing on the Chattahoochee River will be required 
to conduct similar efforts as the river channels with which they are 
associated are not proposed for critical habitat designation, do not 
have any known populations of any of the seven mussels, and do not have 
the capability to affect downstream flow in the manner that the USACE-
operated reservoirs do.
    (67) Comment: One commenter stated that the number and estimated 
impacts of future smaller water supply projects are incorrectly 
estimated and inadequately described.
    Our Response: The report relies on the best available information 
to estimate potential impacts associated with seven mussel conservation 
efforts. In this case, past and current permitting information from the 
U.S. Army Corps of Engineers, and the Georgia Department of 
Environmental Protection is combined with cost estimates for water 
projects in the same geographic area. This represents the best 
information available at this time. The commenter does not provide 
improved information.

Potential Water Quality-Related Impacts

    (68) Comment: One commenter requested that the DEA quantify impacts 
to water quality management.
    Our Response: As discussed in Section 5 of the FEA, agriculture, 
urban stormwater runoff, forestry, and industrial and municipal point 
sources may influence water quality in the proposed critical habitat 
rivers. The economic analysis determined that, overall, these 
activities are not among the major categories of activities that may be 
affected by conservation efforts for the seven mussels.
    (69) Comment: One commenter states that the DEA fails to consider 
the economic effects of lost commercial navigation.
    Our Response: The U.S. Army Corps of Engineers submitted in its 
public comment that ``the State of Florida has denied Section 401 water 
quality certification and Coastal Consistency Certification for the 
Apalachicola River portions of the federal ACF navigation project. The 
denial contained costly alternative provisions that are not currently 
funded by Congress, and it has been agreed to defer dredging unless and 
until additional direction from the U.S. Congress provides necessary 
authority and funding for the Florida requested changes to the dredged 
material management plan for the Apalachicola River. We have estimated 
the additional costs to the navigation project due to the Florida-
requested provisions, but these additional costs are unrelated to 
mussel conservation efforts.''
    Section 6 of the FEA acknowledges USACE's comment and that the 
federal navigation project is still authorized. Given the ongoing 
issues unrelated to mussels that have precluded navigation activities 
in the ACF basin, however, the FEA does not quantify impacts of 
potential changes to navigation. If Congress approves funding for the 
alternatives in Florida's permit conditions, and if Florida provides a 
permit to the USACE to continue navigation dredging activities, and if 
the presence of the seven mussels or their critical habitat then 
affects dredge material disposal or other navigation activities this 
report may have underestimated impacts to navigation.
    (70) Comment: One commenter requested that the DEA quantify impacts 
to sand and gravel mining.
    Our Response: As discussed in Section 6 of the FEA, sand and gravel 
extraction from riverbeds was once common in the ACF Basin, but ceased 
several years ago. Permitting authorities have indicated that future 
operations are unlikely.

Summary of Changes From Proposed Rule

    We have reconsidered our proposed critical habitat designation for 
the seven mussels relative to comments received during the two public 
review periods and three public hearings, the economic analysis, and 
new information that has become available since we published the 
proposed rule on June 6, 2006. Based on information received during the 
first comment period, we made three changes to the proposed critical 
habitat designation, which we published for public comment in the June 
21, 2007, notice of availability for the draft

[[Page 64297]]

economic analysis (72 FR 34215). We now adopt these changes in this 
final rule as follows:
    (1) We enlarge Unit 2 (Chipola River) and Unit 8 (Apalachicola 
River). In Unit 2, we extend the upstream boundary of Big Creek by 5.1 
km (3.2 mi), and add the downstream-most portion of Cowarts Creek (33.5 
km (20.8 mi)). In Unit 8, we add the downstream-most portions of three 
tributaries to the Apalachicola River: River Styx, Kennedy Slough, and 
Kennedy Creek.
    (2) We add the fat threeridge to the list of species associated 
with Unit 7 (Lower Flint River).
    (3) We correct an error by deleting Clayton County, Georgia, from 
the list counties in which the proposed critical habitat units occur.
    We make no further changes to the geographic description of 
critical habitat in this final rule. Otherwise, this final rule differs 
from the proposed rule by minor editorial changes, clarifying revisions 
to one of the PCEs, and clarifying revisions to the discussions that 
support the PCEs. Based on the comments and recommendations we 
received, we have changed the following:
    (1) We revise the substrate quality PCE to clarify the role of fine 
sediments. While excessive amounts of silts and clays accumulating in 
mussel habitat via channel instability and/or erosive land uses are 
harmful to the seven mussels, a moderate amount of silt and clay is 
normal and beneficial throughout most of the range of the seven 
mussels. The substrate quality PCE was proposed as ``A predominantly 
sand, gravel, and/or cobble stream substrate'', and is now stated as: 
``A predominantly sand, gravel, and/or cobble stream substrate with low 
to moderate amounts of silt and clay.''
    (2) To avoid implying that little is known about the tolerances of 
mussels relative to all physical and chemical water quality parameters, 
we revised the statement: ``The ranges of several standard physical and 
chemical water quality parameters (such as temperature, DO, pH, 
conductivity) that define suitable habitat conditions for the seven 
mussels have not been specifically investigated;'' to read instead 
``The temperature, dissolved oxygen (DO), pH, and conductivity ranges 
that define suitable habitat conditions for the seven mussels have not 
been specifically investigated.''
    (3) We revise the discussion of the flowing water PCE to provide 
more information about site-specific flow regime features that are 
relevant to the seven mussels. Specifically, we have added a listing of 
the flow regime features that are included in the Service-USEPA 
instream flow guidelines.
    (4) We correct our characterization of three congeners of the 
shinyrayed pocketbook that were reassigned from the genus Lampsilis to 
the genus Hamiota as species that are not protected under the Act. Two 
of three species are listed under the Act.

Critical Habitat

    Critical habitat is defined in section 3 of the Act as (i) the 
specific areas within the geographical area occupied by a 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) that may require special management 
considerations or protection; and (ii) specific areas outside the 
geographical area occupied by a 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 any endangered species or threatened species to the point at 
which the measures provided under the Act are no longer necessary.
    Critical habitat receives protection under section 7(a)(2) of the 
Act through the prohibition against destruction or adverse modification 
of critical habitat with regard to actions carried out, funded, or 
authorized by a Federal agency. Section 7 of the Act 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 the 
landowner.
    To be included in a critical habitat designation, the habitat 
within the geographical area occupied by the species at the time it was 
listed must contain features that are essential to the conservation of 
the species. Critical habitat designations identify, to the extent 
known using the best scientific data available, habitat areas that 
provide essential life cycle needs of the species (i.e., areas on which 
are found the primary constituent elements, as defined at 50 CFR 
424.12(b)).
    Occupied habitat that contains the features essential to the 
conservation of the species meets the definition of critical habitat 
only if those features may require special management considerations or 
protection.
    Under the Act, we can designate unoccupied areas as critical 
habitat only when we determine that the best available scientific data 
demonstrate that the designation of that area is essential to the 
conservation needs 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, the Service's Policy on Information Standards Under the 
Endangered Species Act, published in the Federal Register on July 1, 
1994 (59 FR 34271), and Section 515 of the Treasury and General 
Government Appropriations Act for Fiscal Year 2001 (Pub. L. 106-554; 
H.R. 5658) and the associated Information Quality Guidelines issued by 
the Service, provide criteria, establish procedures, and provide 
guidance to ensure that decisions are based on the best scientific data 
available. They require Service biologists to the extent consistent 
with the Act and with the use of the best scientific data available, to 
use primary and original sources of information as the basis for 
recommendations to designate critical habitat.
    When determining which areas are critical habitat, a 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. All 
information is used in accordance with the provisions of Section 515 of 
the Treasury and General Government Appropriations Act for Fiscal Year 
2001 (Pub. L. 106-554; H.R. 5658) and the associated Information 
Quality Guidelines issued by the Service.
    Habitat is often dynamic, and species may move from one area to 
another over time. Furthermore, we recognize that designation of 
critical habitat may not include all of the habitat areas that we may 
eventually determine, based on scientific data not now available to the 
Service, are necessary for the recovery of the species. For these 
reasons, critical habitat designations do not signal that habitat 
outside the designation is unimportant or may not be required for 
recovery of the species.
    Areas that support populations of the seven mussels, but are 
outside the critical habitat designation, will continue to be subject 
to conservation

[[Page 64298]]

actions implemented under section 7(a)(1) of the Act and 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 action. Section 7(a)(1) directs all 
other Federal agencies to utilize their authorities in furtherance of 
the purposes of the Act by carrying out programs for the conservation 
of listed species. 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, or 
other species conservation planning efforts, as any new information 
available to these planning efforts calls for a different outcome.

Primary Constituent Elements

    In accordance with section 3(5)(A)(i) of the Act and the 
regulations at 50 CFR 424.12, in determining which areas occupied at 
the time of listing to designate as critical habitat, we consider those 
physical and biological features that are essential to the conservation 
of the species, and within areas occupied by the species at the time of 
listing, that may require special management considerations or 
protection. The physical and biological features essential to the 
conservation of the species are the primary constituent elements (PCEs) 
laid out in an appropriate quantity and spatial arrangement for 
recovery. 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.
    The specific PCEs required for the seven mussels are derived from 
the biological needs of the seven mussels as described in the final 
listing rule (63 FR 12664, March 16, 1998), the proposed critical 
habitat rule (71 FR 32746, June 6, 2006), and information contained in 
this final rule.
    Space for individual and population growth and normal behavior, and 
sites for reproduction and development of offspring are provided for 
the seven mussels on and within the streambed of stable channels with a 
suitable substrate, which we have captured in the PCEs regarding 
channel stability, substrate quality, and flow regime. Because the 
seven mussels are dependent on fish to complete their larval life 
stage, the PCE regarding fish hosts is a further requirement for 
successful reproduction. Various nutritional and physiological 
requirements are captured in the PCEs regarding flow regime and water 
quality. These PCEs are explained in additional detail below.
    Based on our current knowledge of the life history, biology, and 
ecology of the seven mussels, and the habitat requirements for 
sustaining their essential life history functions, we have determined 
that the seven mussels require the PCEs described below.
    PCE 1. A geomorphically stable stream channel (a channel that 
maintains its lateral dimensions, longitudinal profile, and spatial 
pattern over time without a consistent aggrading or degrading bed 
elevation).
    Unstable channels do not favor mussels in part because adults and 
juveniles are relatively sedentary animals. They are unable to move 
quickly or across great distances from unsuitable to suitable 
microhabitats on and in the stream bed. Several researchers have 
reported direct adverse effects to mussels in aggrading (filling) and 
degrading (scouring) channels (Vannote and Minshall 1982, p. 4106; 
Kanehl and Lyons 1992, p. 7; Hartfield 1993, p. 133; Brim Box and Mossa 
1999, p. 99-117). In degrading channels, mussels lose the substrate 
sediment in which they anchor themselves against the current. Mussels 
have been extirpated from streams experiencing a ``headcut'' (stream 
bed degradation progressing in an upstream direction) and from 
degrading reaches immediately downstream of dams. In aggrading channels 
or in channels with actively eroding stream banks, excess sediment 
fouls the gills of mussels, which reduces feeding and respiratory 
efficiency, disrupts metabolic processes, reduces growth rates, and 
physically smothers mussels (Ellis 1936, p. 39; Stansbery and Stein 
1971, p. 2178; Marking and Bills 1979, p. 209-210; Kat 1982, p. 123; 
Vannote and Minshall 1982, p. 4105-4106; Aldridge et al. 1987, p. 18; 
Waters 1995, p. 173-176; Brim Box 1999, p. 65).
    In addition to the direct effects above, channel instability 
indirectly affects mussels and their fish hosts in several ways. 
Channels becoming wider and shallower via bank erosion develop more 
extreme daily and seasonal temperature regimes, which affects dissolved 
oxygen levels and many other temperature-regulated physical and 
biological processes. Mussels in wider and shallower channels are 
likely more susceptible to predation. Erosive channels lose the habitat 
complexity provided by mature bank-side vegetation, which reduces 
diversity and abundance of fish species. Fewer fish means lower 
probability of mussel recruitment. The many direct and indirect adverse 
effects of channel instability on mussels and their fish hosts strongly 
suggest that channel stability is a habitat feature essential to their 
conservation.
    PCE 2. A predominantly sand, gravel, and/or cobble stream substrate 
with low to moderate amounts of silt and clay.
    Adult unionid mussels are generally found in localized patches 
(beds) almost completely burrowed in the substrate with only the area 
around their siphons exposed (Balfour and Smock 1995, p. 255-268). The 
composition and abundance of adult mussels have been linked to bed 
sediment distributions (Neves and Widlak 1987, p. 5; Leff et al. 1990, 
p. 415). Substrate texture (particle size distribution) affects the 
ability of mussels to burrow in the substrate and anchor themselves 
against stream currents (Lewis and Riebel 1984, p.2025). Texture and 
other aspects of substrate composition, including bulk density (ratio 
of mass to volume), porosity (ratio of void space to volume), and 
sediment sorting may also influence mussel densities (Brim Box 1999, p. 
1-86; Brim Box and Mossa 1999, p. 99-117). Although several studies 
have reported adult habitat selection by substrate composition, most 
species are found in a relatively broad range of substrate types 
(Tevesz and McCall 1979, p. 114; Strayer 1981, p. 411; Hove and Neves 
1994, p. 36; Strayer and Ralley 1993, p. 255), with few exceptions 
(Stansbery 1966, p. 29-30). The seven mussels are found in a variety of 
substrates, ranging from pockets of sand on bedrock to sandy mud, but 
only rarely in substrates composed of predominantly fine materials 
(more than 50 percent silt or clay by dry weight) (Brim Box and 
Williams 2000, p. 1-143; Blalock-Herod 2000, p. 1-72). Although 
excessive amounts of fine sediments may adversely affect the seven 
mussels, some amount of silt and clay is a normal component of the 
substrate at most locations at which they are found. In stream beds 
composed mostly of sandy materials, moderate amounts of silt and

[[Page 64299]]

clay increase substrate cohesiveness and local stability.
    Interstitial spaces (pores) in coarse stream substrates may become 
clogged when fine sediment input to streams is excessive (Gordon et al. 
1992, p. 1-444). Reduced pore space and pore flow rates reduce habitat 
for juvenile mussels, which tend to burrow entirely beneath the 
substrate surface, and for some adult mussels as well (Brim Box and 
Mossa 1999, p. 99-117). At least some species of juvenile unionids feed 
primarily on particles associated with sediments and pore water during 
their early development (Yeager et al. 1994, p. 221). Fine sediments 
act as vectors in delivering contaminants such as nutrients, heavy 
metals, and pesticides to streams (Salomons et al. 1987, p. 13). Most 
toxicity data for freshwater mussels is from tests with water-only 
exposures, despite reports that contaminated sediments have contributed 
to mussel declines (Newton 2003, p. 2543; Wilson et al. 1995, p. 213-
218).
    Because the juveniles and adults of the seven mussels live in a 
variety of substrates ranging from pockets of sand on bedrock to sandy 
mud, but only rarely in substrates comprised of more than 50 percent by 
dry weight silt and clay materials, and because the introduction of 
fine-grained sediments and various pollutants is likely detrimental to 
one or more of their life stages, we have determined that substrate 
quality is a habitat feature essential to their conservation.
    PCE 3. Permanently flowing water.
    The species that are the subject of this rule are all riverine 
unionid mussels and are not found in natural or manmade ponds and 
lakes. One known exception is a single large (and presumably old) 
purple bankclimber found in Goat Rock Reservoir on the Chattahoochee 
River by malacologist C. Stringfellow (Columbus State University) in 
2000. Otherwise, none of the seven mussels tolerate impounded 
conditions or persist in intermittent streams (Brim Box and Williams 
2000, p. 1-141); therefore, continuously flowing water is a habitat 
feature associated with all potentially viable populations. Flowing 
water transports food items to the sedentary juvenile and adult life 
stages and provides oxygen for mussel respiration at depths that would 
be anoxic in a pond setting. At least three of the seven mussels are 
known to attract host fishes visually by apparently disguising their 
glochidia as potential prey items (O'Brien and Brim Box 1999, p. 135-
136; O'Brien and Williams 2002, p. 154), and some of these mechanisms 
appear to require flowing water to function effectively as lures. For 
example, flowing water is required to suspend the several-feet-long 
superconglutinate of the shinyrayed pocketbook in the water column so 
that the glochidia packet at the end of it, which resembles a small 
fish, is visible to fish (O'Brien and Brim Box 1999, p. 135, 138).
    Quantifying the amount of flowing water that is essential to the 
conservation of the seven mussels is complicated by the broad size 
range of streams they inhabit, from small tributaries near watershed 
headwaters to the Apalachicola River, which is the world's 82nd largest 
river by discharge (Leopold 1994, p. 101). These seven mussels are 
often found near the toe of stable stream banks associated with roots 
and other instream cover or structure. A flow sufficient to inundate 
the stream bed from bank toe to bank toe with adequately oxygenated 
water deep enough to deter terrestrial predators is several orders of 
magnitude greater at a site on the lower Apalachicola River compared to 
a site on a tributary stream in the upper Ochlockonee River.
    Quantifying the amount of flowing water that is essential to the 
conservation of the seven mussels is also complicated by their 
dependency on various species of fishes to serve as hosts for their 
glochidia. Mussel population viability is likely dependent on features 
of the flow regime that influence fish host population density as well 
as features that directly affect adult and juvenile mussel survival. 
For example, the largemouth bass, which is a lab-verified host for the 
fat threeridge and shinyrayed pocketbook (O'Brien and Brim Box 1999, p. 
136; O'Brien and Williams 2002, p. 150), is known to utilize seasonally 
inundated floodplain habitats for spawning and rearing (Kilgore and 
Baker 1996, p. 291-294), habitats which do not support adult or 
juvenile mussels because they are dry for several months of most years. 
Year class strength of largemouth bass has been positively correlated 
with flows in several river systems due to the additional habitat 
available in high-flow years (Raibley et al. 1997, p. 852-853), and 
fish host density is a factor in mussel recruitment (see ``Fish Hosts'' 
discussion below). Year class strength is abundance of a cohort (born 
in a particular year) relative to other cohorts. A strong year class is 
represented in much greater numbers than a weak year class, presumably 
because the strong year class experienced more favorable conditions for 
recruitment.
    Riverine ecologists have recognized that variable flow creates 
variable physical and chemical conditions that limit the distribution 
and abundance of riverine species (Power et al. 1995, p. 166; Resh et 
al. 1988, p. 443). Altering natural long-term patterns of flow changes 
the structure, composition, and function of riverine communities (Bain 
et al. 1988, p. 382-392; Hill et al. 1991, p. 198-210; Sparks 1995, p. 
172-173; Scheidegger and Bain 1995, p.134). Poff et al. (1997, p.770) 
and Richter et al. (1997b, p. 243) concluded that the accumulated 
research on the relationship between hydrologic variability and 
riverine ecological integrity overwhelmingly supported a ``natural flow 
paradigm,'' that is, the patterns of variability in a river's natural 
flow regime are critical in sustaining its ecological integrity. 
Richter et al. (1996, p. 1165, 1997b, p. 236) proposed a set of 
parameters collectively termed ``indicators of hydrologic alteration'' 
(IHA) for characterizing ecologically relevant features of a flow 
regime.
    The Service and USEPA adapted a subset of the IHA parameters as 
instream flow guidelines for protecting riverine ecosystems under a 
possible interstate water allocation formula between Alabama, Florida, 
and Georgia for the ACF Basin (USFWS and USEPA 1999, p. 1). Although 
the three States failed to agree upon an allocation formula and the ACF 
Compact authorizing their negotiations expired, the Service has applied 
the instream flow guidelines in consultations with Federal agencies on 
actions affecting the species addressed in this rule. The Service-USEPA 
guidelines are definitions of measures of flow magnitude, duration, 
frequency, and seasonality that may serve as thresholds for ``may 
affect'' determinations for proposed Federal actions that would alter a 
flow regime (for example, water withdrawals and dam operations). These 
measures include the following: monthly 1-day minima; annual low-flow 
duration; monthly average flow; annual 1-day maximum; annual high-flow 
duration. Thresholds for these measures are computed from long-term 
flow records appropriate to the proposed action, such as daily flow 
records from a stream gage in the action area. It is not practical or 
useful to compute the flow guidelines for the entire region that this 
designation spans, because the guidelines were designed as a tool for 
site- and project-specific analysis. Further, the guidelines do not 
establish a general standard or ``bottom line'' for flow regime 
features that are essential to the conservation of listed species. 
Recognizing the many complexities involved in quantifying essential 
flow regime features for the seven mussels,

[[Page 64300]]

we have adopted a qualitative expression that applies throughout the 
range of the seven mussels and is clearly necessary for their 
conservation: ``permanently flowing water.''
    PCE 4. Water quality (including temperature, turbidity, dissolved 
oxygen, and chemical constituents) that meets or exceeds the current 
aquatic life criteria established under the Clean Water Act (CWA) (33 
U.S.C. 1251-1387).
    The temperature, dissolved oxygen (DO), pH, and conductivity ranges 
that define suitable habitat conditions for the seven mussels have not 
been specifically investigated. As sedentary animals, mussels must 
tolerate the full range of these parameters to persist in a stream. 
Quantifying water quality tolerances for the seven mussels is further 
complicated by their dependency on fish hosts, which may exhibit 
different tolerances.
    Most mussels are considered sensitive to low DO levels and high 
temperatures (Fuller 1974, p. 245). Johnson (2001, p. 8-11) monitored 
water quality and mussel mortality during a drought year in the lower 
Flint River Basin. Low DO levels, which occurred during low flow 
periods, were associated with high weekly mussel mortality. Species-
specific mortality varied considerably. The shinyrayed pocketbook and 
Gulf moccasinshell were among the species with the highest mortality 
rates when exposed to DO concentrations less than 5 milligrams per 
liter (mg/L). The oval pigtoe demonstrated moderate, but significantly 
higher than average, mortality when DO was less than 5 mg/L.
    Juvenile mussels may spend their first few years buried in the 
sediments of the stream bed. Interstitial water (pore water) in 
sediments is generally less oxygenated than flowing water in the stream 
above (Sparks and Strayer 1998, p. 129). Sparks and Strayer (1998, p. 
132) observed marked differences in behavior between juvenile Eastern 
elliptio (Elliptio complanata), congener of the Chipola slabshell, that 
were exposed to DO levels of 2 mg/L and 4 mg/L, and most juveniles of 
this species that were exposed to 1.3 mg/L for a week died. In general, 
juveniles are sensitive to low DO levels. Interstitial DO levels in 
streams of the eastern United States are usually less than 4 mg/L in 
the summer and may fall below 1 mg/L (Sparks and Strayer 1998, p. 132).
    Water temperature affects the amount of oxygen that can be 
dissolved in water and the toxicity of various pollutants. The toxic 
effects of ammonia are more pronounced at higher temperatures and at 
higher pH (Mummert et al. 2003, p. 2545, 2550; Newton 2003, p. 2543). 
High temperatures or decreasing pH may increase the toxicity of metals 
to unionids (Havlik and Marking 1987, p. 14). Watters and O'Dee (2000, 
p. 136) suggested that the release of glochidia is regulated by water 
temperature. In Texas, exceptionally warm temperatures appeared to 
prompt early initiation of mussel reproductive activity, and cool 
temperatures appeared to delay activity (Howells 2000, p. 40). 
Temperature may affect immune system response in fish. Some fish 
species that reject infections by mussel glochidia at higher 
temperatures are infected at lower temperatures (Roberts and Barnhart 
1999, p. 484).
    Various contaminants in point- and non-point-source discharges can 
degrade water and substrate quality and adversely affect mussel 
populations (Horne and McIntosh 1979, p. 119-133; Neves and Zale 1982, 
p. 53; McCann and Neves 1992, p. 77-81; Havlik and Marking 1987, p. 1-
20). Naimo (1995, p. 341) suggested that chronic, low-level 
contamination of streams may explain the widespread decreases in mussel 
density and diversity. Mussels appear to be among the organisms most 
sensitive to heavy metals (Keller and Zam 1991, p. 539), several of 
which are lethal at relatively low levels (Havlik and Marking 1987, p. 
3). Cadmium appears to be the most toxic (Havlik and Marking 1987, p. 
3), although copper, mercury, chromium, and zinc may also impair 
physiological processes (Jacobson et al. 1993, p. 879; Naimo 1995, p. 
353-355; Keller and Zam 1991, p. 539-546; Keller and Lydy 1997, p. 3). 
Metals stored in mussel tissues indicate recent or current exposure 
(Havlik and Marking 1987, p. 12), while concentrations in shell 
material indicate past exposure (Imlay 1982, p. 7; Mutvei et al. 1994, 
p. 163-186). Highly acidic pollutants such as metals may contribute to 
mussel mortality by dissolving shells (Stansbery 1995, p. 2-3). Low 
levels of some metals may inhibit glochidial attachment (Huebner and 
Pynn[ouml]nen 1992, p. 2349). Mussel recruitment may be reduced in 
habitats with low but chronic heavy metal and other toxicant inputs 
(Yeager et al. 1994, p. 221; Naimo 1995, p. 341; Ahlstedt and 
Tuberville 1997, p. 72-77).
    Water pollutants associated with agricultural activity may 
adversely affect mussels. Arsenic trioxide, which is used in the 
poultry industry as a feed additive, is lethal to adult mussels at 
concentrations of 16.0 parts per million (ppm), and ammonia is lethal 
at concentrations of 5.0 ppm (Havlik and Marking 1987, p. 3, 13). 
Ammonia is associated with animal feedlots, nitrogenous fertilizers, 
and the effluents of older municipal wastewater treatment plants. 
Ammonia causes a shift in glucose metabolism (Chetty and Indira 1995, 
p. 84) and alters the utilization of lipids, phospholipids, and 
cholesterol (Chetty and Indira 1994, p. 693). Stream ecosystems are 
altered when nutrients are added at concentrations that cannot be 
assimilated (Stansbery 1995, p. 2-3). Excessive nutrients promote the 
growth of filamentous algae in streams, which may render substrates 
unsuitable for mussels of all life stages and degrade water quality by 
consuming oxygen during night-time respiration and during decay to 
levels that mussels cannot tolerate. Several studies have described 
adverse effects of pesticides on mussels (Fuller 1974, p. 215-257; 
Havlik and Marking 1987, p. 13; Moulton et al. 1996, p. 131). Commonly 
used pesticides were cited as the likely cause of a mussel die-off in a 
North Carolina stream (Fleming et al. 1995, p. 877-879).
    Gourdreau et al. (1993, p. 211-230) examined mussel populations 
relative to the discharges of two municipal wastewater treatment plants 
on the Clinch River in Tazewell County, Virginia. Mussels were absent 
or present in low numbers immediately downstream of these discharges, 
but occurred in greater diversity and abundance immediately upstream 
and farther downstream. The investigators hypothesized that, in 
addition to chemicals of known toxicity to glochidia, the bacteria and 
protozoans associated with wastewater discharges may also adversely 
affect mussel reproduction. Glochidia are vulnerable to attack by 
bacteria and protozoans before and after they are released from the 
adult female mussel (Fuller 1974, p. 219; Goudreau et al. 1993, p. 
221).
    Adults of some mussel species may tolerate short-term exposure to 
various contaminants by closing their valves (Keller 1993, p. 701). 
Juveniles and glochidia appear more sensitive than adults to heavy 
metals (McCann and Neves, 1992, p. 77-81) and to ammonia (Goudreau et 
al. 1993, p. 224). Ammonia is lethal to juveniles at concentrations as 
low as 0.7 ppm total ammonia nitrogen, normalized to pH 8, and lethal 
to glochidia at concentrations as low as 2.4 ppm (Augspurger et al. 
2003, p. 2569-2575). In streams, ammonia may occur at highest 
concentrations in substrate interstitial spaces where juvenile mussels 
live and feed (Whiteman et al. 1996, p. 794; Hickey and Martin 1999, p. 
38; Augspurger et al. 2003, p. 2569-2575).

[[Page 64301]]

    In general, we believe the numeric standards for pollutants and 
water quality parameters (for example, heavy metals and DO) that are 
adopted by the States under the CWA represent levels that are essential 
to the conservation of the seven mussels. However, some State standards 
may not adequately protect mussels, such as the standard for ammonia 
(Augspurger et al. 2003, p. 2571; Newton et al. 2003, p. 2559). USEPA 
and FWS and National Marine Fisheries Service (the Services) agreed to 
a national consultation on the CWA Section 304(a) aquatic life criteria 
as part of a Memorandum of Agreement regarding interagency coordination 
under the CWA and the Act (66 FR 11202, February 22, 2001). The 
criteria for some pollutants, such as ammonia, are presently under 
review. Although the State standards adopted consistent with the USEPA 
criteria generally represent levels that are safe for the seven 
mussels, these standards are sometimes violated in some streams within 
their current range. Rather than specify the ranges of dozens of water 
quality parameters for the seven mussels, it is more practical to deal 
with cases where the national criteria are not protective of these and 
other listed species under the national consultations with USEPA. For 
purposes of this rule, the evidence for the dependency of the seven 
mussels on good water quality supports identifying water quality 
generally as a habitat feature that is essential to their conservation.
    PCE 5. Fish hosts (such as largemouth bass, sailfin shiner, brown 
darter) that support the larval life stages of the seven mussels.
    Most unionid mussels, including the seven species, parasitize fish 
during the larval life stage, depending on fish hosts not only for the 
physiological transformation from larval to juvenile form (Isom and 
Hudson 1982, p. 147-151), but also for spatial dispersal (Neves 1993, 
p. 4). The distribution and diversity of unionids is strongly related 
to the distribution and diversity of fish species (Watters 1992, p. 
488; Haag and Warren 1998, p. 298). Bogan (1993, p. 600) identified the 
dependency of mussels on fish hosts, which are affected by exploitation 
and a variety of common habitat alterations, as one of several 
contributing causes in the extinction of several unionid species 
worldwide. Haag and Warren (1998, p. 303) identified host fish 
availability and density as significant factors influencing where 
certain mussel populations can persist.
    Although female mussels may produce 75,000 to 3.5 million glochidia 
(Surber 1912, p. 3-10; Coker et al. 1921, p. 144; Yeager and Neves 
1986, p. 333), contact of the glochidia with a suitable host fish is a 
low-probability event (Neves et al. 1997, p. 60). Contact is dependent 
on many factors, including the timely presence of the host fish, the 
feeding and respiratory behaviors of the fish (Dartnall and Walkey 
1979, p. 36; Neves et al. 1985, p. 17-18), and for some species, the 
behavior of the mussel when the fish is present (Davenport and Warmuth 
1965, p. R77; Kraemer 1970, p. 225-282). Contact between glochidia and 
host fish does not ensure successful larval development to the juvenile 
form, because some fish species have natural immunity to glochidial 
infestation and others acquire immunity following infestation (Watters 
and O'Dee 1996, p. 387). Glochidia that contact a host with natural 
immunity are rejected and die, usually within 11 days (Neves et al. 
1985, p. 15, 17; Yeager and Neves 1986, p. 338; Waller and Mitchell 
1989, p. 86). In the case of acquired immunity, glochidia experience 
decreased transformation rates with subsequent infections of an 
initially suitable host fish (Arey 1932, p. 372; Bauer and Vogel 1987, 
p. 393; Luo 1993, p. 26). The number of exposures associated with 
glochidial sloughing is variable (Watters and O'Dee 1996, p. 385, 387).
    As few as 1 to as many as 25 fish species are known to serve as 
suitable hosts for particular species of mussels (Fuller 1974, p. 238; 
Trdan and Hoeh 1982, p. 386; Gordon and Layzer 1989, p. 1-98; Hoggarth 
1992, p. 3). Some mussels are host-fish specialists that parasitize a 
few fish species (Zale and Neves 1982, p. 2540; Yeager and Saylor 1995, 
p. 4; Neves et al. 1985, p. 13, 17), and others are generalists that 
parasitize a great variety of host fishes (Trdan and Hoeh 1982, p. 
386). Generally, mussels that are known host-fish specialists tend to 
release glochidia in conglutinates (multiple glochidia in a packet 
versus a stream of single glochidia) or use various means of attracting 
a fish host before releasing multiple glochidia (Watters 1997, p. 45). 
Because fish that are not naturally immune to glochidial infection 
develop some immunity after infection, securing a host fish is to some 
degree a ``first come, first served'' situation. Some researchers have 
hypothesized that mussels may compete for fish hosts (Watters 1997, p. 
57; Trdan and Hoeh 1982, p. 384-385).
    Watters (1997, p. 45-62) developed individual-based models of 
mussel-fish interactions to simulate unionid reproductive strategies, 
showing specialists tended to have lower population sizes and were less 
sensitive to fluctuating host fish density than generalists, which 
attained much higher population sizes when host fish density was high 
and declined when host fish density declined.
    Haag and Warren (1998, p. 297-306) examined patterns of fish and 
mussel community composition in two north Alabama drainages. They found 
that densities of host-generalist mussels and of host-specialist 
mussels with elaborate host-attracting mechanisms were independent of 
host-fish densities, and were present throughout the two drainages. 
Densities of host-specialist mussels without elaborate host-attracting 
mechanisms were positively correlated with host-fish densities and were 
absent or rare near the drainages' headwaters.
    Host-fish specificity has been examined in laboratory tests for 
five of the seven mussels: The fat threeridge, Gulf moccasinshell, oval 
pigtoe, purple bankclimber (O'Brien and Williams 2002, p. 151), and 
shiny-rayed pocketbook (O'Brien and Brim Box 1999, 136). The fat 
threeridge lacks mantle modifications or other morphological 
specializations that would serve to attract host fishes and appears to 
be a host-fish generalist that may infect fishes of at least three 
different fish families. Glochidia transformed to juveniles under 
laboratory conditions on five of seven fish species tested: weed shiner 
(Notropis texanus), bluegill (Lepomis macrochirus), redear sunfish (L. 
microlophus), largemouth bass (Micropterus salmoides), and blackbanded 
darter (Percina nigrofasciata) (O'Brien and Williams 2002, p. 152).
    The elaborate superconglutinate of the shiny-rayed pocketbook 
suggests it is a host-fish specialist that targets sight-feeding 
piscivorous fishes, such as bass. O'Brien and Brim Box (1999, p. 136) 
confirmed that largemouth bass and spotted bass (Micropterus 
punctulatus) are likely primary hosts (all fishes infected produced 
juvenile mussels) among 11 species tested. Low transformation rates 
were associated with fish such as the eastern mosquitofish (Gambusia 
holbrooki) and bluegill.
    The Gulf moccasinshell is probably a host-fish specialist that 
primarily parasitizes darters. It visually lures host fish by 
undulating its dark mantle flaps against swollen white gills (O'Brien 
and Williams 2002, p. 154). O'Brien and Williams (2002, p. 152) lab-
tested eight fish species for suitability as hosts, finding that all 
black-banded darters and brown darters (Etheostoma edwini) exposed to 
infection transformed glochidia to juveniles. Other fishes, including 
the eastern mosquitofish, also

[[Page 64302]]

transformed glochidia, but at lower percentage rates.
    The extreme rarity of the Ochlockonee moccasinshell has precluded 
any opportunities to explore its life history. We assume its 
reproductive biology is similar to its congener, the Gulf 
moccasinshell, which uses darters as host fish.
    The oval pigtoe releases rigid white to pinkish conglutinates, 
which passively drift in the current and may resemble the food 
organisms of small-bodied fishes. O'Brien and Williams (2002, p. 152) 
tested 11 fish species as hosts, finding that glochidia transformed on 
the gills of fish such as the sailfin shiner (Pteronotropis 
hypselopterus) and eastern mosquitofish. They considered only the 
sailfin shiner as a primary host, as it was the only species upon which 
the transformation rate exceeded 50 percent.
    We are aware of no studies of the reproductive biology of the 
Chipola slabshell. It is likely that the species expels glochidia in a 
conglutinate, as do several other members of the genus Elliptio that 
occur in the ACF Basin (Brim Box and Williams 2000, p. 34-47). Keller 
and Ruessler (1997, p. 402-407) identified centrarchids (sunfishes) as 
host fishes of other southeastern Elliptio.
    O'Brien and Williams (2002, p. 153) observed in the laboratory that 
purple bankclimber conglutinates readily disintegrated when they 
contained mature glochidia, and these were easily suspended in the 
water by the aerators in their holding tanks. They speculated that the 
species may rely on stream currents to carry glochidia to host fish, 
which is typical of host-fish generalist species. Of the 14 fish 
species they tested as potential hosts, only a few species transformed 
glochidia, including the eastern mosquitofish and blackbanded darter. 
Only the mosquito fish was 100 percent effective (all fish tested 
transformed glochidia), but it is an unlikely primary host fish. The 
mosquito fish occupies backwater areas and stream margins with little 
or no current (Lee et al. 1980, p. 1-854), while the bankclimber is 
found mostly in the main channels of larger streams and rivers. The 
primary host fishes of the purple bankclimber are still unknown.
    Data that might suggest densities of the various primary host fish 
species named above that are sufficient to support normal mussel 
recruitment and dispersal rates are not available. Stochastic 
simulations of fish'mussel interactions indicate that mussel 
populations are extirpated if a threshold host fish density is not 
exceeded (Watters 1997, p. 60). Further studies of fish and mussel 
population dynamics are necessary to quantify species-specific 
thresholds; however, we recognize that the presence of host fish is a 
biological habitat feature essential to the conservation of the seven 
mussels.
    This designation is designed for the conservation of PCEs necessary 
to support the life history functions of the species and the areas 
containing these PCEs. We propose units for designation based on 
sufficient PCEs being present to support at least one of the species' 
life history functions. Some units contain all of these PCEs and 
support multiple life processes, while some units contain only a 
portion of these PCEs, those necessary to support the species' 
particular use of that habitat.

Special Management Considerations or Protections

    When designating critical habitat, we assess whether the occupied 
areas contain the features essential to the conservation of the species 
that may require special management considerations or protections. 
Activities in or adjacent to each of the critical habitat units 
described in this rule may affect one or more of the PCEs that are 
found in the unit. These activities include, but are not limited to, 
those listed in the Adverse Modification Standard section as activities 
that may affect critical habitat. We find that the features essential 
to each of the seven mussel species contained within the areas of this 
designation may require special management considerations or 
protections due to known or probable threats from these activities. We 
summarize here the nature of the threats and the resulting conservation 
needs for both the mussels and their host fish across the range of the 
seven mussels.
    Sedimentation is an almost ubiquitous threat in the range of the 
seven mussels. A wide variety of activities, such as livestock grazing, 
road and bridge construction, clear-cut logging, and off-road vehicle 
use, that are common in all 11 units may increase erosion rates, either 
in the banks of the stream channel itself or elsewhere in the 
watershed, and cause the accumulation of fine sediments on the stream 
bed. Management considerations to deal with this threat include 
protecting streams from sedimentation through application of 
agricultural and forestry best management practices, avoiding soil- and 
vegetation-disturbing activity in the riparian zone, restoring unstable 
stream channels and other erosive areas, and other practices that 
prevent or reduce erosion.
    Urbanization, road and bridge construction, and other large-scale 
alterations of land cover that substantially alter the runoff 
characteristics of the watershed may threaten channel stability in 
units near the major urban areas of Dothan, Alabama (unit 2); Panama 
City and Tallahassee, Florida (units 1 and 10); Albany, Atlanta, and 
Columbus, Georgia (units 3, 5, 6, and 7); and other cities. Management 
considerations to deal with the threat of channel instability include 
avoiding soil- and vegetation-disturbing activity in the riparian zone, 
limiting impervious surface area, and other urban storm water runoff 
control methods. Sand and gravel mining (unit 3), dredging and 
channelization (unit 8), and dam construction (unit 5) may also affect 
channel stability.
    The construction and operation of dams, water withdrawals, and 
water diversions may alter features of the flow regime important to the 
mussels and their host fishes. This threat is present to some degree in 
all 11 units, but is greatest in units 5, 6, 7, 8, and 10, which are 
downstream of the major mainstem dams or are areas of relatively high 
municipal, industrial, or agricultural water use. Measures to deal with 
this threat include water conservation and operational strategies that 
manage water storage capacity and water demands in combination to 
minimize departures from the natural flow regime.
    Water pollution, especially from non-point (dispersed release) 
sources, is another almost ubiquitous threat in all 11 units. Water 
quality is reported as impaired or potentially impaired in some 
portions of all four river basins within the current range of the seven 
mussels, according to the water quality agencies of the three States in 
their periodic assessments under Section 305(b) of the Clean Water Act 
(CWA) (see ``Summary of Threats to Surviving Populations'' in the 
proposed rule published in the Federal Register on June 6, 2006 (71 FR 
32746)). Streams that receive a high proportion of their flow from the 
discharge of springs are vulnerable to nutrient enrichment from 
fertilizers and to other pollutants applied in the recharge areas of 
those springs (units 1, 2, and 7), which may extend far from the 
streams themselves. Management considerations to deal with the threat 
of pollution include applying agricultural and forestry best management 
practices, preserving native vegetation in riparian zones, maintaining 
septic systems, and taking other measures to minimize pollutant-laden 
runoff to streams.

[[Page 64303]]

Criteria Used To Identify Critical Habitat

    As required by section 4(b)(1) of the Act, we used the best 
scientific and commercial data available in determining areas that 
contain the features that are essential to the conservation of the 
seven mussels. We reviewed the available information pertaining to 
their historical and current distributions, life histories, host 
fishes, habitats, and threats to mussels in general, and threats to the 
seven mussels in particular. This information includes our own site-
specific species and habitat data; unpublished survey reports; notes 
and communications with other qualified biologists or experts; peer-
reviewed scientific publications; the final listing rule for the seven 
mussels; and our final recovery plan for the seven mussels.
    Our principal sources of information for identifying the specific 
areas within the occupied range of the seven mussels on which are found 
those features essential to their conservation were: the collective 
database of locality records for the seven mussels, which is tabulated 
in our 2003 final recovery plan and has been supplemented with surveys 
completed since then, and the peer-reviewed scientific literature on 
mussels' life history and habitat requirements. Our 1998 final listing 
rule relied extensively upon data obtained in a rangewide status survey 
of the seven mussels commissioned by the Service and conducted in 1991 
and 1992 (cited as Butler (1993, p. 1-30) in the final listing). Most 
of these data were taken in the ACF basin and have since been published 
by Brim Box and Williams (2000, p. 3). Although mussel surveys have 
been conducted since publication of the final listing rule at various 
locations in the four river basins that encompass their known range, 
the 1991-1992 status survey still provides a majority of the most 
recent distributional records for these seven mussels. For purposes of 
this final rule, the Service considers the most recent post-1990 survey 
data at a particular location as representing a species' current 
presence or absence at that location, and we consider pre-1990 survey 
data as representing historical distribution. We must extend the 
definition of current distribution back to 1990 because mussels are 
sedentary, long-lived animals, some species attaining maximum life 
spans of 100 to 200 years (Neves and Moyer 1988, p. 185; Bauer 1992, p. 
425; Mutvei et al. 1994, p. 163-186). It was rare in the 1991-1992 
survey, and is still rare, to find juveniles of the seven mussels.
    We relied on a variety of information sources for identifying 
occupied areas in which the features essential to the conservation of 
the seven mussels may require special management considerations or 
protection, including land and water management plans of State and 
regional government agencies, surveys of stream channel condition, 
water quality assessments, and distributional information for host 
fishes. We used the sources cited in our final recovery plan's summary 
of known threats to the seven mussels to identify which essential 
features may be most vulnerable in certain portions of the occupied 
range.
    We began our analysis by examining the full extent of each species' 
historical and current range. As discussed under ``Summary of Threats 
to Surviving Populations'' in the proposed rule published in the 
Federal Register on June 6, 2006, (71 FR 32746) , the declining range 
and abundance of the seven mussels is due mostly to changes in their 
riverine habitats resulting from dams, dredging, mining, 
channelization, pollution, sedimentation, and water withdrawals. The 
Econfina, ACF, Ochlockonee, and Suwannee drainages contain about 54,000 
km (33,500 mi) of perennial streams (USGS 1:100,000 National 
Hydrography Data). From mussel survey records, the historical range of 
the seven mussels collectively spanned about 3,300-km (2,050-mi), or 6 
percent, of the river and stream channels in these drainages, but no 
one species accounts for more than about 2,300 km (1,445 mi) of that 
total (USFWS 2003, p. 78-80). We estimate that the five species listed 
as endangered are each extirpated from over half of their historical 
range, and the two threatened species are extirpated from about one-
third of theirs, but none are extirpated entirely from the four major 
drainages in which they each occurred historically. All seven mussels 
were more widespread and more abundant within each of the four 
drainages historically.
    The largest single portion of the historical range lost to the 
seven mussels is the mainstem of the Chattahoochee River. The 
Chattahoochee comprised over 700 km (435 mi), or almost one-quarter, of 
the 3,300-km (2,050-mi) collective historical range, and supported the 
shinyrayed pocketbook, Gulf moccasinshell, oval pigtoe, and purple 
bankclimber. It is now impounded by several major dams for much of its 
length and no longer supports the listed mussels. With the exception of 
a single live animal found in Goat Rock Reservoir in 2000, the purple 
bankclimber appears extirpated from the entire Chattahoochee Basin, but 
at least one of the other three species persist in three of its 
tributaries: Uchee Creek, Sawhatchee Creek, and Kirkland Creek. 
Elsewhere in the four major drainages, the pattern of extirpation is 
more variable, with one or more of the seven species persisting in 
portions of a drainage where others have disappeared. The collective 
range of the seven species now spans about 1,900 km (1,180 mi) of river 
and stream channels. Within this collective range, the species 
presently occur in as little as 55 km (34 mi) (the Ochlockonee 
moccasinshell) to as much as 785 km (488 mi) (the shinyrayed 
pocketbook) (USFWS 2003, p. 78-80).
    To identify the specific areas that were occupied at the time of 
listing by each of the seven mussels and that contain one or more of 
the PCEs, we used post-1990 mussel survey results. Because mussels are 
sedentary and long-lived animals, occupancy is strong evidence that 
some or all of the PCEs are present, except where it is apparent that 
one or a few adult individuals remain at a location with little or no 
possibility of reproducing due to substantial habitat alteration (such 
as the single purple bankclimber found in Goat Rock Reservoir). It is 
not feasible to survey all potential habitat for the seven species; 
therefore, to delineate a species' occupied range in the larger stream 
network, it is necessary to extrapolate from the available survey data. 
Most of the tributary streams in the four basins that may support one 
or more of the seven species have never been surveyed, and we are not 
designating any unsurveyed streams as critical habitat. We used USGS 
1:100,000 digital stream maps to delineate the probable upstream and 
downstream limits to the seven species' distribution in streams 
surveyed since 1990, according to the criteria listed below. These 
limits form the boundaries of critical habitat units as explained 
below.
    (a) The lateral boundaries of a unit are the ordinary high-water 
marks on each bank of currently occupied streams. We recognize the 
dynamic nature of riverine systems and that floodplains and riparian 
areas are integral parts of those systems. Processes that occur and 
habitat characteristics that are found outside the stream banks are 
important in maintaining channel morphology, providing energy and 
nutrients, and protecting the instream environment from pollutants and 
excessive sediments. Similarly, floodplain and backwater habitats may 
be important in the life cycle of fish that serve as hosts for mussel 
larvae. Although factors affecting the PCEs may occur outside

[[Page 64304]]

the channel, the PCEs themselves occur within the channel.
    (b) The upstream boundary of a unit in an occupied stream is the 
first perennial tributary confluence or first permanent barrier to fish 
passage (such as a dam) upstream of the upstream-most current 
occurrence record. Many of the mussel survey sites are located near 
watershed headwaters. In these areas, the confluence of a tributary 
typically marks a significant change in the size of the stream and is a 
logical and recognizable upstream boundary for habitat conditions that 
are similar to the upstream-most occurrence record. Likewise, a dam or 
other barrier to fish passage marks the upstream extent to which 
mussels at the upstream-most occurrence may disperse via their fish 
hosts. Therefore, a unit encapsulates habitat containing essential 
features used by host fish and the seven mussels for successful natural 
reproductive process. Habitat above these boundaries does not contain 
features essential to the conservation of the species.
    (c) The downstream boundary of a unit in an occupied stream is the 
mouth of the stream, the upstream extent of tidal influence, or the 
upstream extent of an impoundment, whichever comes first, downstream of 
the downstream-most occurrence record. Many survey sites are located 
near the mouths of streams, the upstream extent of impoundments, or the 
upstream extent of tidal influence. Survey locations are typically at 
road crossings, because that is where surveyors can most easily gain 
access to the stream. These road crossings do not typically represent a 
meaningful ecological boundary for longitudinal stream habitat 
conditions. Mussels are dispersed via host fish, and because these host 
fish traverse freely in the area between the upstream-most occurrence 
and any existing downstream restriction to fish passage, larvae drop 
off their host fish at random points along the stream flow segments 
traversed by fish. Further, the sperm of all seven species and the 
conglutinates (glochidia packets) of some of the seven may be carried 
downstream by currents and are viable for several hours to several days 
unless they reach unsuitable habitat conditions, such as intolerable 
salinity or still water, in which either would sink to the bottom and 
be smothered in the sediments. Therefore, we are designating stream 
segments that have mussel point locations from the upstream limit as 
defined in (b) above to the downstream location where the PCEs are no 
longer present.
    The application of these criteria resulted in the identification of 
11 units occupied by one or more of the seven mussels and that contain 
one or more of the PCEs as indicated by the presence and persistence of 
one or more of the listed mussels (see ``Critical Habitat 
Designation''). Based on fish distributional records (Lee et al. 1980, 
p. 1-854) and our experience sampling fish in these drainages, these 
areas also support shiners, darters, and other fishes that have been 
identified as hosts or potential hosts for one or more of the seven 
mussels.
    When determining critical habitat boundaries, we made every effort 
to avoid including within the boundaries of the map contained within 
this final rule developed areas such as buildings, paved areas, and 
other structures that lack PCEs for the seven mussels. The scale of the 
maps prepared under the parameters for publication within the Code of 
Federal Regulations may not reflect the exclusion of such developed 
areas. Any such structures and the land under them inadvertently left 
inside critical habitat boundaries shown on the maps of this final rule 
have been excluded by text in the rule and are not designated as 
critical habitat. Therefore, Federal actions limited to these areas 
would not trigger section 7 consultation, unless they affect the 
species or PCEs in adjacent critical habitat.
    We are designating 11 critical habitat units in areas that were 
occupied at the time of listing and contain sufficient PCEs to support 
life history functions essential for the conservation of the species, 
which may require special management considerations or protection. Each 
unit is a collection of stream segments that flow unimpeded by fish 
passage barriers into a common reservoir or estuary. One or more of the 
seven listed species persist at locations that are distributed across 
the full breadth of each unit, including one or more locations in each 
stream segment listed in the unit descriptions that follow. Each of the 
11 units designated as critical habitat contain all of the PCEs, and 
each stream segment listed in the unit descriptions contains one or 
more of the PCEs. Most segments contain all PCEs and support multiple 
life processes. Some segments may contain only a portion of the PCEs 
necessary to support long-term use of that habitat, due to the dynamic 
nature of the riverine environment.
    A brief discussion of each area designated as critical habitat is 
provided in the unit descriptions below. Additional detailed 
documentation concerning the essential nature of these areas is 
contained in our supporting record for this rulemaking.

Critical Habitat Designation

    We are designating 11 groups of river and stream segments (units) 
as critical habitat for the fat threeridge, shinyrayed pocketbook, Gulf 
moccasinshell, Ochlockonee moccasinshell, oval pigtoe, Chipola 
slabshell, and purple bankclimber. The river and stream segments 
comprising each unit are contiguous to allow for the movement of fish 
hosts dispersing the larval life stages of the seven mussels within the 
unit. Barriers to the movement of fish hosts (dams and salt water) 
separate the units from each other. Each unit is designated only for 
those species that currently occupy it.
    The critical habitat units described below constitute our best 
assessment currently of areas that meet the definition of critical 
habitat for the species. The 11 units, and the States in which they 
occur, are: (1) Econfina Creek (FL), (2) Chipola River (AL, FL), (3) 
Uchee Creek (AL), (4) Sawhatchee Creek and Kirkland Creek (GA), (5) 
Upper Flint River (GA), (6) Middle Flint River (GA), (7) Lower Flint 
River (GA), (8) Apalachicola River (FL), (9) Upper Ochlockonee River 
(FL, GA), (10) Lower Ochlockonee River (FL), and (11) Santa Fe River 
and New River (FL). Collectively, the total length of the river and 
stream segments of all of the areas (units) designated is approximately 
1,908.5 km (1,185.9 mi). Table 1 shows the approximate length of rivers 
and streams designated as occupied critical habitat for each of the 
seven mussels in the 11 units.

[[Page 64305]]



    Table 1.--Length of Critical Habitat Units Designated for the Fat
   Threeridge, Shinyrayed Pocketbook, Gulf Moccasinshell, Ochlockonee
      Moccasinshell, and Oval Pigtoe, Chipola Slabshell, and Purple
                               Bankclimber
------------------------------------------------------------------------
                                                      Length
   Species, critical habitat unit, and   -------------------------------
                state(s)                    Kilometers         Miles
------------------------------------------------------------------------
             Fat threeridge
2. Chipola River, AL, FL................          228.7           142.1
7. Lower Flint River, GA................          396.7           246.5
8. Apalachicola River, FL...............          161.2           100.2
                                         -------------------------------
    Total...............................          786.6           488.8
 
          Shinyrayed pocketbook
2. Chipola River, AL, FL................          228.7           142.1
3. Uchee Creek, AL......................           34.2            21.2
4. Sawhatchee Creek and Kirkland Creek,            37.8            23.5
 GA.....................................
5. Upper Flint River, GA................          380.4           236.4
6. Middle Flint River, GA...............          302.3           187.8
7. Lower Flint River, GA................          396.7           246.5
9. Upper Ochlockonee River, FL, GA......          177.3           110.2
                                         -------------------------------
    Total...............................         1557.4           967.7
 
           Gulf moccasinshell
1. Econfina Creek, FL...................           31.4            19.5
2. Chipola River, AL, FL................          228.7           142.1
4. Sawhatchee Creek and Kirkland Creek,            37.8            23.5
 GA.....................................
5. Upper Flint River, GA................          380.4           236.4
6. Middle Flint River, GA...............          302.3           187.8
7. Lower Flint River, GA................          396.7           246.5
                                         -------------------------------
    Total...............................         1377.3           855.8
 
        Ochlockonee moccasinshell
9. Upper Ochlockonee River, FL, GA......          177.3           110.2
                                         -------------------------------
    Total...............................          177.3           110.2
 
               Oval pigtoe
1. Econfina Creek, FL...................           31.4            19.5
2. Chipola River, AL, FL................          228.7           142.1
4. Sawhatchee Creek and Kirkland Creek,            37.8            23.5
 GA.....................................
5. Upper Flint River, GA................          380.4           236.4
6. Middle Flint River, GA...............          302.3           187.8
7. Lower Flint River, GA................          396.7           246.5
9. Upper Ochlockonee River, FL, GA......          177.3           110.2
11. Santa Fe and New Rivers, FL.........           83.1            51.6
                                         -------------------------------
    Total...............................         1637.7          1017.6
 
            Chipola slabshell
2. Chipola River, AL, FL................          228.7           142.1
                                         -------------------------------
    Total...............................          228.7           142.1
           Purple bankclimber
5. Upper Flint River, GA................          380.4           236.4
6. Middle Flint River, GA...............          302.3           187.8
7. Lower Flint River, GA................          396.7           246.5
8. Apalachicola River, FL...............          161.2           100.2
9. Upper Ochlockonee River, FL, GA......          177.3           110.2
10. Lower Ochlockonee River, FL.........           75.4            46.9
                                         -------------------------------
    Total...............................         1493.3           928
                                         -------------------------------
        Total Designated for All 11             1,908.50        1,185.90
         Units (All Species)............
------------------------------------------------------------------------

    States were granted ownership of lands beneath navigable waters up 
to the ordinary high water mark upon achieving statehood (Pollard v. 
Hagan, 44 U.S. (3 How.) 212 (1845)). Prior sovereigns or the States may 
have made grants to private parties that included lands below the 
ordinary high water mark of some navigable waters that are included in 
this rule. We believe that most, if not all, lands beneath the 
navigable waters included in this rule are owned by the States of 
Alabama, Florida, and Georgia. The lands beneath most nonnavigable 
waters and most riparian lands along the navigable and nonnavigable 
waters included in this rule are in private ownership. Table 2 lists 
the parcels of publicly owned lands within or adjacent to each 
designated critical habitat unit. Units not listed do not contain 
publicly owned lands.

[[Page 64306]]



Table 2.--Public Lands Within or Adjacent to Designated Critical Habitat
                                  Units
------------------------------------------------------------------------
    Critical habitat unit                     Public lands
------------------------------------------------------------------------
1. Econfina Creek............  Econfina Creek WtrMA.
2. Chipola River.............  Upper Chipola River WtrMA, South Marianna
                                Trail and Canoe Launch, Apalachicola
                                River WtrMA, Apalachicola River WEA,
                                Chipola River GW, Florida Caverns SP,
                                Judges Cave WEA, Marianna GW.
5. Upper Flint...............  Joe Kurz WMA, Sprewell Bluff SP and WMA,
                                Big Lazer WMA, Montezuma NA, Flint River
                                WMA.
7. Lower Flint...............  Flint River GW, Radium Springs Tract,
                                Chickasawhatchee WMA, Elmodel WMA, Lake
                                Seminole WMA.
8. Apalachicola River........  Angus Gholson Jr. Nature Park of
                                Chattahoochee, Apalachicola River WtrMA,
                                Apalachicola River WEA, Fort Gadsden HS,
                                Torreya SP, Apalachicola NF.
9. Upper Ochlockonee.........  Joe Budd WMA, Lake Talquin SF.
10. Lower Ochlockonee........  Lake Talquin SP, Lake Talquin SF, Tate's
                                Hell SF, Apalachicola NF.
11. Santa Fe River and New     Santa Fe River Ranch, O'Leno SP, River
 River.                         Rise Preserve SP, Graham CA, Palatka-
                                Lake Butler ST.
------------------------------------------------------------------------
Abbreviations: CA=Conservation Area, GW=Greenway, HS=Historic Site,
  NA=Natural Area, NF=National Forest, SF=State Forest, SP=State Park,
  ST=State Trail, WEA=Wildlife and Environmental Area, WMA=Wildlife
  Management Area, WtrMA=Water Management Area.

    Brief descriptions of each unit follow, listing the rivers and 
streams included, the upstream and downstream extent of the unit in 
those rivers and streams, and which of the seven mussels were present 
at the time of listing. Each critical habitat unit includes the 
channels of the rivers and streams listed between the ordinary high 
water mark on each bank, which is defined in 33 CFR 329.11 as ``the 
line on the shore established by the fluctuations of water and 
indicated by physical characteristics such as a clear, natural line 
impressed on the bank; shelving; changes in the character of soil; 
destruction of terrestrial vegetation; the presence of litter and 
debris; or other appropriate means that consider the characteristics of 
the surrounding areas.'' In the unit descriptions, distances between 
landmarks marking the upstream or downstream extent of a particular 
stream in the unit are given in kilometers (km) and equivalent miles 
(mi), as measured tracing the course of the stream, not straight-line 
distance.
Unit 1: Econfina Creek, Florida
    Unit 1 includes the main stem of Econfina Creek and one of its 
tributaries in Bay and Washington counties, Florida, encompassing a 
total stream length of 31.4 km (19.5 mi). The main stem of Econfina 
Creek as designated extends from its confluence with Deer Point Lake at 
the powerline crossing located 3.8 km (2.3 miles) downstream of Bay 
County Highway 388, Bay County, Florida, upstream 28.6 km (17.8 mi) to 
Tenmile Creek in Washington County, Florida. Unit 1 also includes the 
tributary stream Moccasin Creek from its confluence with Econfina Creek 
upstream 2.8 km (1.7 mi) to Ellis Branch in Bay County. Unit 1 is 
designated for the Gulf moccasinshell and oval pigtoe (Blalock-Herod 
unpub. data 2002-03; Brim Box unpub. data 1996; Williams unpub. data 
1993). PCEs in Unit 1 are vulnerable to impacts from sedimentation, 
urbanization, and pollution, as described under ``Special Management 
Considerations or Protections.''
Unit 2: Chipola River, Alabama and Florida
    Unit 2 includes the main stem of the Chipola River (including the 
reach known as Dead Lake) and six of its tributaries, encompassing a 
total stream length of 190.0 km (118.1 mi) in Houston County, Alabama; 
and in Calhoun, Gulf, and Jackson counties, Florida. The main stem of 
the Chipola River as designated extends from its confluence with the 
Apalachicola River in Gulf County, Florida, upstream 144.9 km (90.0 mi) 
to the confluence of Marshall and Cowarts creeks in Jackson County, 
Florida. A short segment of the Chipola River that flows underground 
within the boundaries of Florida Caverns State Park in Jackson County, 
Florida, is not included in Unit 2. The downstream extent of each 
tributary within the unit is its mouth (its confluence with the water 
body named), and the upstream extent is the landmark listed. The 
tributaries of the Chipola River included in Unit 2 are: Dry Creek, 
from the Chipola River upstream 7.6 km (4.7 mi) to Ditch Branch in 
Jackson County, Florida; Rocky Creek, from the Chipola River upstream 
7.1 km (4.4 mi) to Little Rocky Creek in Jackson County, Florida; 
Waddells Mill Creek, from the Chipola River upstream 3.7 km (2.3 mi) to 
Russ Mill Creek in Jackson County, Florida; Baker Creek, from Waddells 
Mill Creek upstream 5.3 km (3.3 mi) to the confluence with Tanner 
Springs in Jackson County, Florida; Marshall Creek, from the Chipola 
River upstream 13.7 km (8.5 mi) to the Alabama-Florida State line in 
Jackson County, Florida (this creek is known as Big Creek in Alabama); 
Big Creek, from the Alabama-Florida State line upstream 13.0 river km 
(8.1 river mi) to Limestone Creek, in Houston County, Alabama; and 
Cowarts Creek from the Chipola River in Jackson County, Florida, 
upstream 33.5 river km (20.8 river mi) to the Edgar Smith Road bridge, 
in Houston County, Alabama.
    This unit is designated for the fat threeridge (Brim Box and 
Williams 2000, p. 92-93; Miller 1998, p. 54), shinyrayed pocketbook 
(Williams unpub. data 2002; Brim Box and Williams 2000, p. 109-110; 
Smith unpub. data 2001; Blalock-Herod unpub. data 2000, 2003; Butler 
unpub. data 1993, 1994, 1999, 2000); Gulf moccasinshell (Butler unpub. 
data 1999, 2002; Brim Box and Williams 2000, p. 113-114; D.N. Shelton 
pers. comm. 1998); oval pigtoe (Butler unpub. data 1993, 1999, 2002; 
Brim Box and Williams 2000, p. 116-117; Williams unpub. data 2000); and 
Chipola slabshell (Butler unpub. data 1993, 2000; Brim Box and Williams 
2000, p. 95-96). PCEs in Unit 2 are vulnerable to impacts from 
sedimentation, urbanization, and pollution, as described under 
``Special Management Considerations or Protections.''
Unit 3: Uchee Creek, Alabama
    Unit 3 encompasses 34.2 km (21.2 mi) of the main stem of Uchee 
Creek from its confluence with the Chattahoochee River upstream to 
Island Creek in Russell County, Alabama. This unit is designated for 
the shinyrayed pocketbook (Brim Box and Williams 2000, p. 109-110; 
Gangloff unpublished data 2005). PCEs in Unit 3 are vulnerable to 
impacts from sedimentation, urbanization, and pollution, as described 
under ``Special Management Considerations or Protections.''
Unit 4: Sawhatchee Creek and Kirkland Creek, Georgia
    Unit 4 includes the main stems of Sawhatchee Creek and Kirkland 
Creek and one tributary of Sawhatchee Creek, encompassing a total 
stream length of 37.8 km (23.5 mi) in Early County, GA.

[[Page 64307]]

The main stem of Sawhatchee Creek as designated extends from its 
confluence with the Chattahoochee River upstream 28.6 km (17.8 mi) to 
the powerline crossing located 1.4 km (0.87 mi) upstream of County Road 
15, Early County, GA. The main stem of Kirkland Creek extends from its 
confluence with the Chattahoochee River upstream 6.1 km (3.8 mi) to Dry 
Creek, Early County, GA. The tributary, Sheffield Mill Creek, is 
included from its confluence with Sawhatchee Creek upstream 3.1 km (1.9 
mi) to the powerline crossing located 2.3 km (1.4 mi) upstream of 
Sowhatchee Road, Early County, GA. Unit 4 is designated for the 
shinyrayed pocketbook, Gulf moccasinshell, and oval pigtoe (Brim Box 
and Williams 2000, p. 109-110, 113-114, 116-117; Abbott pers. comm. 
2005; Stringfellow pers. comm. 2003). PCEs in Unit 4 are vulnerable to 
impacts from sedimentation and pollution, as described under ``Special 
Management Considerations or Protections.''
Unit 5: Upper Flint River, Georgia
    Unit 5 includes the main stem of the Flint River and eight of its 
tributaries upstream of Lake Blackshear, plus two tributaries that flow 
into Lake Blackshear, encompassing a total stream length of 380.4 km 
(236.4 mi) in Coweta, Crawford, Crisp, Dooly, Fayette, Macon, 
Meriwether, Peach, Pike, Spalding, Sumter, Talbot, Taylor, Upson, and 
Worth counties, Georgia. The main stem of the Flint River in designated 
Unit 5 extends from the State Highway 27 bridge (Vienna Road) in Dooly 
and Sumter counties, Georgia (the river is the county boundary), 
upstream 247.4 km (153.7 mi) to Horton Creek in Fayette and Spalding 
counties, Georgia (the river is the county boundary). The downstream 
extent of each tributary within the unit is its mouth (its confluence 
with the water body named), and the upstream extent is the landmark 
listed. The nine tributary streams in Unit 5 are: Swift Creek, from 
Lake Blackshear upstream 11.3 km (7 mi) to Rattlesnake Branch in Crisp 
and Worth counties, Georgia (the creek is the county boundary); 
Limestone Creek, from Lake Blackshear in Crisp County, Georgia, 
upstream 8.8 km (5.5 mi) to County Road 89 in Dooly County, Georgia; 
Turkey Creek, from the Flint River upstream 21.7 km (13.5 mi) to Rogers 
Branch in Dooly County, Georgia; Pennahatchee Creek, from Turkey Creek 
upstream 4.8 km (3 mi) to Little Pennahatchee Creek in Dooly County, 
Georgia; Little Pennahatchee Creek, from Pennahatchee Creek upstream 
5.8 km (3.6 mi) to Rock Hill Creek in Dooly County, Georgia; Hogcrawl 
Creek, from the Flint River upstream 21.6 km (13.4 mi) to Little Creek 
in Dooly and Macon counties, Georgia (the creek is the county 
boundary); Red Oak Creek, from the Flint River upstream 21.7 km (13.5 
mi) to Brittens Creek in Meriwether County, Georgia; Line Creek, from 
the Flint River upstream 15.8 km (9.8 mi) to Whitewater Creek in Coweta 
and Fayette counties, Georgia (the creek is the county boundary); and 
Whitewater Creek, from Line Creek upstream 21.5 km (13.4 mi) to Ginger 
Cake Creek in Fayette County, Georgia.
    Unit 5 is designated for the shinyrayed pocketbook (Dinkins pers. 
comm. 1999, 2003; P.D. Johnson pers. comm. 2003; Brim Box and Williams 
2000, p. 109-110; Roe 2000; L. Andrews pers. comm. 2000; Blalock-Herod 
unpub. data 1997; Butler and Brim Box 1995, p. 3); Gulf moccasinshell 
(Edwards Pittman Environmental 2004; McCafferty pers. comm. 2003; 
Dinkins pers. comm. 2002; Brim Box and Williams 2000, p. 113-114; 
Andrews pers. comm. 2000; Blalock-Herod unpub. data 1997; Butler and 
Brim Box 1995, p. 3); oval pigtoe (Edwards Pittman Environmental 2004; 
McCafferty pers. comm. 2003; Dinkins pers. comm. 2002, 2003; 
Stringfellow pers. comm. 2000, 2003; Abbott pers. comm. 2001; Brim Box 
and Williams 2000, p. 116-117; Andrews pers. comm. 2000; Blalock-Herod 
unpub. data 1997); and purple bankclimber (Winterringer CCR pers. comm. 
2003; Dinkins pers. comm. 2003; P.D. Johnson pers. comm. 2003; Albanese 
pers. comm. 2003 regarding unpub. data from De Genachete and CCR; Brim 
Box and Williams 2000, p. 105-106; E. Van De Genachete pers. comm. 
1999). PCEs in Unit 5 are vulnerable to impacts from sedimentation, 
urbanization, hydrologic alteration, and pollution, as described under 
``Special Management Considerations or Protections.''
    Unit 5 is divided into two maps in the Regulation Promulgation 
section of this rule, one for the southern part and one for the 
northern part of the unit. The ``match line'' for joining these two 
maps is where the county boundary between Crawford and Upson counties, 
Georgia, meets the Flint River.
Unit 6: Middle Flint River, Georgia
    Unit 6 includes the main stem of the Flint River between Lake Worth 
(impounded by the Flint River Dam near Albany) and the Warwick Dam 
(which impounds Lake Blackshear), and nine tributaries, encompassing a 
total stream length of 302.3 km (187.8 mi) in Dougherty, Lee, Marion, 
Schley, Sumter, Terrell, Webster, and Worth counties, Georgia. The main 
stem of the Flint River in Unit 6 extends from Piney Woods Creek in 
Dougherty County, Georgia (the approximate upstream extent of Lake 
Worth), upstream 39.9 km (24.8 mi) to the Warwick Dam in Lee and Worth 
counties, Georgia. The downstream extent of each tributary within the 
unit is its mouth (its confluence with the water body named), and the 
upstream extent is the landmark listed. The nine tributaries of the 
Middle Flint River in Unit 6 are: Kinchafoonee Creek, from the Lee-
Dougherty county line (the approximate upstream extent of Lake Worth) 
upstream 107.6 km (66.8 mi) to Dry Creek in Webster County, Georgia; 
Lanahassee Creek, from Kinchafoonee Creek upstream 9.3 km (5.8 mi) to 
West Fork Lanahassee Creek in Webster County, Georgia; Muckalee Creek, 
from the Lee-Dougherty county line (the approximate upstream extent of 
Lake Worth) upstream 104.5 km (64.9 mi) to County Road 114 in Marion 
County, Georgia; Little Muckalee Creek, from Muckalee Creek in Sumter 
County, Georgia, upstream 7.2 km (4.5 mi) to Galey Creek in Schley 
County, Georgia; Mill Creek, from the Flint River upstream 3.2 km (2 
mi) to Mercer Millpond Creek in Worth County, Georgia; Mercer Millpond 
Creek, from Mill Creek upstream 0.45 km (0.28 mi) to Mercer Millpond in 
Worth County, Georgia; Abrams Creek, from the Flint River upstream 15.9 
km (9.9 mi) to County Road 123 in Worth County, Georgia; Jones Creek, 
from the Flint River upstream 3.8 km (2.4 mi) to County Road 123 in 
Worth County, Georgia; and Chokee Creek, from the Flint River upstream 
10.5 km (6.5 mi) to Dry Branch Creek in Lee County, Georgia.
    Unit 6 is designated for the shinyrayed pocketbook (Crow CCR pers. 
comm. 2004; Edwards Pittman Environmental 2004; Albanese pers. comm. 
2003 regarding unpub. data from CCR; DeGarmo unpub. data 2002; 
McCafferty pers. comm. 2000, 2001; Golladay unpub. data 2001, 2002; P. 
Johnson unpub. data 1999; Blalock-Herod unpub. data 1997; Dinkins pers. 
comm. 1995; Brim Box and Williams 2000, p. 109-110), Gulf moccasinshell 
(Wisnewski unpub. data 2005; DeGarmo unpub. data 2002; Albanese pers. 
comm. 2003 regarding unpub. data from D. Shelton; P. Johnson unpub. 
data 1999; Brim Box and Williams 2000, p. 113-114; Weston 1995), oval 
pigtoe (Wisnewski unpub. data 2005; Crow CCR pers. comm. 2004; Albanese 
pers. comm. 2003 regarding unpub. data from CCR; DeGarmo unpub. data 
2002;

[[Page 64308]]

Stringfellow unpub. data 2002; Golladay unpub. data 2001, 2002; Brim 
Box and Williams 2000, p. 116-117; P. Johnson unpub. data 1999; 
Blalock-Herod unpub. data 1997; Weston 1995), and purple bankclimber 
(Tarbell 2004; Brim Box and Williams 2000, p. 105-106). PCEs in Unit 6 
are vulnerable to impacts from sedimentation, urbanization, hydrologic 
alteration, and pollution, as described under ``Special Management 
Considerations or Protections.''
    Unit 6 is divided into two maps in the Regulation Promulgation 
section of this rule, one for the western part and one for the eastern 
part of the unit. The ``match line'' for joining these two maps is Lake 
Worth in Dougherty County, Georgia.
Unit 7: Lower Flint River, Georgia
    Unit 7 includes the main stem of the Flint River between Lake 
Seminole (impounded by the Jim Woodruff Lock and Dam) and the Flint 
River Dam (which impounds Lake Worth), and nine tributaries, 
encompassing a total stream length of 396.7 km (246.5 mi) in Baker, 
Calhoun, Decatur, Dougherty, Early, Miller, Mitchell, and Terrell 
counties, GA. The main stem of the Flint River in Unit 7 extends from 
its confluence with Big Slough in Decatur County, GA (the approximate 
upstream extent of Lake Seminole) upstream 116.4 km (72.3 mi) to the 
Flint River Dam in Dougherty County, GA. The downstream extent of each 
tributary within the unit is its mouth (its confluence with the water 
body named), and the upstream extent is the landmark listed. The nine 
tributaries of the Lower Flint River in Unit 7 are: Spring Creek, from 
Smith Landing in Decatur County, Georgia (the approximate upstream 
extent of Lake Seminole), upstream 74.2 km (46.1 mi) to County Road 35 
in Early County, Georgia; Aycocks Creek, from Spring Creek upstream 
15.9 km (9.9 mi) to Cypress Creek in Miller County, Georgia; Dry Creek, 
from Spring Creek upstream 9.9 km (6.1 mi) to Wamble Creek in Early 
County, Georgia; Ichawaynochaway Creek, from the Flint River in Baker 
County, Georgia, upstream 68.6 km (42.6 mi) to Merrett Creek in Calhoun 
County, Georgia; Mill Creek, from Ichawaynochaway Creek upstream 7.4 km 
(4.6 mi) to County Road 163 in Baker County, Georgia; Pachitla Creek, 
from Ichawaynochaway Creek upstream 18.9 km (11.8 mi) to Little 
Pachitla Creek in Calhoun County, Georgia; Little Pachitla Creek, from 
Pachitla Creek upstream 5.8 km (3.6 mi) to Bear Branch in Calhoun 
County, Georgia; Chickasawhatchee Creek, from Ichawaynochaway Creek in 
Baker County, GA, upstream 64.5 km (40.1 mi) to U.S. Highway 82 in 
Terrell County, Georgia; and Cooleewahee Creek, from the Flint River 
upstream 15.1 km (9.4 mi) to Piney Woods Branch in Baker County, 
Georgia.
    Unit 7 is designated for the shinyrayed pocketbook (Gangloff 2005; 
McCafferty pers. comm. 2004; Stringfellow unpub. data 2003; Dinkins 
pers. comm. 2001, 2003; Golladay unpub. data 2001, 2002; P. Johnson 
unpub. data 1999; Albanese pers. comm. 2003 regarding unpub. data from 
CCR; Andrews pers. comm. 2000; Blalock-Herod unpub. data 1997; Brim Box 
and Williams 2000, p. 109-110; Butler unpub. data 1993), Gulf 
moccasinshell (Abbott pers. comm. 2005; Golladay unpub. data 2001, 
2002; P. Johnson unpub. data 1999; Brim Box and Williams 2000, p. 113-
114; Butler unpub. data 1998; Blalock-Herod unpub. data 1997), oval 
pigtoe (Dinkins pers. comm. 2001; Golladay unpub. data 2001, 2002; 
Andrews pers. comm. 2000; Brim Box and Williams 2000, p. 116-117; P. 
Johnson unpub. data 1999; Butler unpub. data 1998; Blalock-Herod unpub. 
data 1997), and purple bankclimber (S. Carlson unpub. data 2002; Brim 
Box and Williams 2000, p. 105-106). PCEs in Unit 7 are vulnerable to 
impacts from sedimentation, urbanization, hydrologic alteration, and 
pollution, as described under ``Special Management Considerations or 
Protections.''
    Unit 7 is divided into two maps in the Regulation Promulgation 
section of this rule, one for the western part and one for the eastern 
part of the unit. The western part (Map 10) depicts the Spring Creek 
system and the eastern part (Map 11) depicts the lower Flint River 
system.
Unit 8: Apalachicola River, Florida
    Unit 8 includes the main stem of the Apalachicola River; two 
distributaries (channels flowing out of the main stem), and three 
tributaries, encompassing a total stream length of 155.4 km (96.6 mi) 
in Calhoun, Franklin, Gadsden, Gulf, Jackson, and Liberty counties, 
Florida. The main channel of the Apalachicola River in Unit 8 extends 
from the downstream end of Bloody Bluff Island (river mile 15.3 on U.S. 
Army Corps of Engineers Navigation Charts) in Franklin County, Florida, 
upstream to the Jim Woodruff Lock and Dam in Gadsden and Jackson 
counties, Florida (the river is the county boundary). The upstream 
extent of each distributary within the unit is its point of departure 
from the main channel of the Apalachicola River, and its downstream 
extent is the landmark listed. The two distributaries of the 
Apalachicola River in Unit 6 are: Chipola Cutoff, from the Apalachicola 
River in Gulf County, Florida, downstream 4.5 km (2.8 mi) to its 
confluence with the Chipola River in Gulf County, Florida; and Swift 
Slough, from the Apalachicola River in Liberty County, Florida, 
downstream 3.6 km (2.2 mi) to its confluence with the River Styx in 
Liberty County, Florida. The downstream extent of each tributary within 
the unit is its confluence (mouth) with the main channel of the 
Apalachicola River, and its upstream extent is the landmark listed. The 
three tributaries of the Apalachicola River within the unit are: River 
Styx from the mouth of Swift Slough in Liberty County, Florida, 
downstream 3.8 km (2.4 mi) to its mouth; Kennedy Slough from -85.07 
longitude, 30.01 latitude in Liberty County, Florida, downstream 0.9 km 
(0.5 mi) to its confluence with Kennedy Creek; and Kennedy Creek from 
Brushy Creek Feeder (-85.06 longitude, 30.01 latitude) in Liberty 
County, Florida, downstream 1.1 km (0.7 mi) to its mouth.
    Unit 8 is designated for the fat threeridge (Brim Box and Williams 
2000, p. 92-93; Williams unpub. data 2000; Miller 1998, p. 54, 2000; 
Richardson and Yokley 1996, p. 137; Flakes 2001) and purple bankclimber 
(Brim Box and Williams 2000, p. 105-106; Miller 1998, p. 55, 2000; 
Richardson and Yokley 1996, p. 137; Butler unpub. data 1993; Flakes 
2001). PCEs in Unit 8 are vulnerable to impacts from sedimentation, 
hydrologic alteration, and pollution, as described under ``Special 
Management Considerations or Protections.''
Unit 9: Upper Ochlockonee River, Florida, Georgia
    Unit 9 includes the main stem of the Ochlockonee River upstream of 
Lake Talquin (impounded by the Jackson Bluff Dam) and three 
tributaries, encompassing a total stream length of 177.3 km (110.2 mi) 
in Gadsden and Leon counties, Florida, and Grady and Thomas counties, 
Georgia. The main stem of the Ochlockonee River in Unit 9 extends from 
its confluence with Gulley Branch (the approximate upstream extent of 
Lake Talquin) in Gadsden and Leon counties, Florida (the river is the 
county boundary), upstream to Bee Line Road/County Road 306 in Thomas 
County, Georgia. The downstream extent of each tributary within the 
unit is its mouth (its confluence with the water body named), and the 
upstream extent is the landmark listed. The three tributary streams in 
Unit 9 are: Barnetts Creek, from the Ochlockonee River upstream 20 km 
(12.4 mi) to Grady County Road 170/

[[Page 64309]]

Thomas County Road 74 in Grady and Thomas counties, Georgia (the creek 
is the county boundary); West Barnetts Creek, from Barnetts Creek 
upstream 10 km (6.2 mi) to GA Highway 111 in Grady County, Georgia; and 
Little Ochlockonee River, from the Ochlockonee River upstream 13.3 km 
(8.3 mi) to Roup Road/County Road 33 in Thomas County, Georgia.
    Unit 9 is designated for the shinyrayed pocketbook (Blalock-Herod 
2003, p. 1; McCafferty pers. comm. 2003; Williams unpub. data 1993), 
Ochlockonee moccasinshell (Brim Box and Williams 2000, p. 60; Williams 
and Butler 1994, p. 64), oval pigtoe (Edwards Pittman Environmental 
2004; Blalock-Herod unpub. data 2003; Blalock-Herod 2003, p. 1; 
Williams unpub. data 1993), and purple bankclimber (Blalock-Herod 
unpub. data 2003; Blalock-Herod 2002, p. 1; Smith FDOT unpub. data 
2001; Williams unpub. data 1993). PCEs in Unit 9 are vulnerable to 
impacts from sedimentation and pollution, as described under ``Special 
Management Considerations or Protections.''
Unit 10: Lower Ochlockonee River, Florida
    Unit 10 encompasses 75.4 km (46.9 mi) of the main stem of the 
Ochlockonee River from its confluence with Syfrett Creek in Wakulla 
County, Florida, upstream to the Jackson Bluff Dam (which impounds Lake 
Talquin) in Leon and Liberty counties, Florida. Unit 10 is designated 
for the purple bankclimber (Blalock-Herod unpub. data 2003; Williams 
unpub. data 1993). PCEs in Unit 10 are vulnerable to impacts from 
sedimentation, urbanization, hydrologic alteration, and pollution, as 
described under ``Special Management Considerations or Protections.''
Unit 11: Santa Fe River and New River, Florida
    Unit 11 includes the main stem of the Santa Fe River and its 
tributary the New River, encompassing a total stream length of 83.1 km 
(51.6 mi) in Alachua, Bradford, Columbia, and Union counties, Florida. 
The main stem of the Santa Fe River as designated extends from where 
the river goes underground in O'Leno State Park in Alachua and Columbia 
counties, Florida (the river is the county boundary) upstream 60.2 km 
(37.4 mi) to the powerline crossing located 1.9 km (1.2 mi) downstream 
of U.S. Highway 301 in Alachua and Bradford counties, Florida (the 
river is the county boundary). The New River in Unit 11 extends from 
its confluence with the Santa Fe River at the junction of Alachua, 
Bradford, and Union counties, Florida, upstream 22.9 km (14.2 mi) to 
McKinney Branch in Bradford and Union counties, Florida (the river is 
the county boundary). Unit 11 is designated for the oval pigtoe 
(Blalock-Herod and Williams 2001, p. 5; Blalock-Herod 2000, p. 1-72; 
Williams unpub. data 1993, 1996-98). PCEs in Unit 11 are vulnerable to 
impacts from sedimentation and pollution, as described under ``Special 
Management Considerations or Protections.''

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 5th and 9th Circuit Court of Appeals have invalidated our 
definition of ``destruction or adverse modification'' (50 CFR 402.02) 
(see Gifford Pinchot Task Force v. U.S. Fish and Wildlife Service, 378 
F. 3d 1059 (9th Cir 2004) and Sierra Club v. U.S. Fish and Wildlife 
Service et al., 245 F.3d 434, 442F (5th Cir 2001)), and we do not rely 
on this regulatory definition when analyzing whether an action is 
likely to destroy or adversely modify critical habitat. Under the 
statutory provisions of the Act, we determine destruction or adverse 
modification on the basis of whether, with implementation of the 
proposed Federal action, the affected critical habitat would remain 
functional (or retain the current ability for the PCEs to be 
functionally established) 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. ``Reasonable and prudent alternatives'' are defined 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.
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 would retain its current ability 
for the PCEs to be functionally established. 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 seven mussels. Generally, the conservation 
role of the seven mussels critical habitat units is to support viable 
core area populations.
    Section 4(b)(8) of the Act requires us to briefly evaluate and 
describe in any proposed or final regulation that

[[Page 64310]]

designates critical habitat those activities involving a Federal action 
that may destroy or adversely modify such habitat, or that may be 
affected by such designation.
    Activities that, when carried out, funded, or authorized by a 
Federal agency, may affect critical habitat and, therefore, should 
result in consultation for the seven mussels include, but are not 
limited to:
    (1) Actions that would induce channel instability or significantly 
alter channel morphology. Such activities could include, but are not 
limited to, channelization, impoundment, road and bridge construction, 
mining, dredging, destruction of riparian vegetation, and changes in 
land cover, such as urbanization and clear-cut logging, that 
substantially alter the runoff characteristics of the watershed. These 
activities may alter sediment and water discharge in the channel, which 
results in smothering the stream bed with, or eroding it to, materials 
that are unsuitable substrates for the normal behavior, growth, and 
survival of the adult and juvenile life stages. These activities may 
initiate or accelerate bank erosion, which results in wider and 
shallower channels, more extreme temperatures, and chemical properties 
that are unsuitable for the normal behavior, growth, and survival of 
one or more life stages.
    (2) Actions that would significantly decrease the proportion of 
coarse sediments (sand, gravel, cobble) in the stream bed. Such 
activities could include, but are not limited to, sedimentation from 
livestock grazing, road and bridge construction, mining, dredging, 
timber harvest, off-road vehicle use, and other activities that 
increase erosion rates in the channel or the watershed and deposition 
of fine sediments. These activities could reduce or eliminate the 
coarse substrates that provide for the normal behavior, growth, and 
survival of all life stages, and could increase the exposure of the 
juvenile and adult life stages to harmful contaminants that adhere to 
fine sediments.
    (3) Actions that would significantly alter the flow regime. Such 
activities could include, but are not limited to, the construction and 
operation of dams, water withdrawals, water diversions, and changes in 
land cover that substantially alter the runoff characteristics of the 
watershed, such as urbanization and clear-cut logging. These activities 
could alter the spatial distribution, timing, and duration of depths 
and velocities in the channel that provide for the normal behavior, 
growth, and survival of one or more mussel life stages.
    (4) Actions that would significantly alter physical and chemical 
water conditions. Such activities could include, but are not limited 
to, the release of chemicals, nutrients, biological pollutants, or 
heated effluents into the surface water or connected groundwater at a 
point source or by dispersed release (non-point source). These 
activities could alter water conditions that provide for the normal 
behavior, growth, and survival of one or more mussel life stages. These 
activities could promote the excessive growth of filamentous algae and 
other organisms that preclude the normal behavior, growth, and survival 
of one or more mussel life stages.
    (5) Actions that would significantly reduce the density of host 
fishes. Such activities could include, but are not limited to, 
channelization, impoundment, mining, and dredging. These activities 
could alter the composition of the fish community such that the rate of 
host fish infection and completion of the larval life stage is too low 
to sustain a stable or increasing mussel population and normal rates of 
dispersal and genetic exchange with other areas.
    We consider all of the units designated as critical habitat to 
contain features essential to the conservation of the seven mussels. 
All of the units are within the geographic range of the seven species, 
were occupied at the time of listing (based on surveys completed 1990 
to 1998), and are likely occupied currently (based on additional 
surveys between 1998 and the present, and on the longevity and relative 
immobility of mussels).
Application of Section 4(b)(2) of the Act
    Section 4(b)(2) of the Act states that critical habitat shall be 
designated, and revised, 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 Secretary is afforded broad discretion, and the 
Congressional record is clear that, in making a determination under the 
section, the Secretary has discretion as to which factors and how much 
weight will be given to any factor. .

Economic Impacts

    Economic analyses typically measure impacts against a baseline, 
which is normally described as the way the world would look absent the 
proposed action. This is often referred to as the ``incremental'' 
approach. In 2001, the U.S. Tenth Circuit Court of Appeals found that 
the incremental approach provided ``meaningless'' results and 
instructed the Service to conduct a full analysis of all of the 
economic impacts of proposed critical habitat, regardless of whether 
those impacts are attributable coextensively to other causes (New 
Mexico Cattle Growers Assn v. U.S.F.W.S., 248 F.3d 1277 (10th Cir. 
2001)). However, since that decision, courts in several other cases 
have held or implied that an incremental analysis is proper (see Cape 
Hatteras Access Preservation Alliance v. Department of Interior, 344 F. 
Supp. 2d 108 (D.D.C.); CBD v. BLM, 422 F. Supp/.2d 1115 (N.D. Cal. 
2006).
    Accordingly, we have reevaluated the baseline used for critical 
habitat economic analyses. The economic analysis should use a 
traditional regulatory analysis approach and examine the economic 
impact of the regulatory change being considered. However, because 
there is interest by the courts and the public in seeing the total 
costs of regulation, the analyses should quantify the existing 
regulatory baseline. When quantifying the baseline, the analyses should 
look back to the time of listing.
    When estimating the incremental impacts of the critical habitat 
designation, the Service must consider that most courts have agreed 
with the New Mexico Cattle Growers court when it determined that the 
Service cannot simply equate adverse modification standard and the 
jeopardy standard and conclude that there are no economic costs. The 
New Mexico Cattle Growers court said ``Congress clearly intended that 
economic factors were to be considered.'' Therefore, when conducting 
this analysis, it is important to attempt to distinguish between the 
regulation that would exist prior to the designation of critical 
habitat, under the jeopardy standard, and under Sections 9 and 10 of 
the Act, and the additional regulation that would exist with 
designation of critical habitat.
    Following the publication of the proposed critical habitat 
designation, we conducted an economic analysis to estimate the 
potential economic effect of the designation. This draft analysis was

[[Page 64311]]

based on the coextensive approach only and estimated the potential 
future impacts associated with conservation efforts for the seven 
mussels in areas proposed for critical habitat designation. The draft 
analysis was made available for public review on June 21, 2007 (72 FR 
34215). We accepted comments on the draft analysis until August 6, 
2007. The final economic analysis added the incremental approach, which 
can be found in Appendix B of the report.
    The primary purpose of the economic analysis is to estimate the 
potential economic impacts associated with the designation of critical 
habitat for the seven mussels. This information is intended to assist 
the Secretary in making decisions about whether the benefits of 
excluding particular areas from the designation outweigh the benefits 
of including those areas in the designation. This economic analysis 
considers the economic efficiency effects that may result from the 
designation, including habitat protections that may be coextensive with 
the listing of the species and the incremental impacts of the critical 
habitat designation itself. It also addresses distribution of impacts, 
including an assessment of the potential effects on small entities and 
the energy industry. This information can be used by the Secretary to 
assess whether the effects of the designation might unduly burden a 
particular group or economic sector. We based our decision on whether 
to exclude any areas due to economic reasons on the incremental impacts 
in the final economic analysis.
    The final economic analysis evaluated the potential future effects 
associated with the listing of the seven mussels, as well as any 
potential effect of the designation of critical habitat above and 
beyond those regulatory and economic impacts associated with the 
listing. To quantify the proportion of total potential economic impacts 
attributable to the critical habitat designation, the analysis 
evaluated a ``without critical habitat'' baseline and compared it to a 
``with critical habitat'' scenario. The ``without critical habitat'' 
baseline represented the current and expected economic activity under 
all modifications prior to the critical habitat designation, including 
protections afforded the species under Federal and State laws. The 
difference between the two scenarios measured the net change in 
economic activity attributable to the designation of critical habitat.
    The economic analysis estimates total potential future impacts 
associated with conservation efforts for the seven mussels in areas 
designated to be $83.1 million to $135.0 million over the next 20 years 
(undiscounted). The present value of these impacts is $62.3 million to 
$101.0 million, using a discount rate of three percent, or $45.0 
million to $71.7 million, using a discount rate of seven percent. The 
annualized value of these impacts is $4.13 million to $6.70 million, 
using a discount rate of three percent, or $4.13 million to $6.60 
million, using a discount rate of seven percent. All of these impacts 
are baseline impacts and are not expected to be affected by critical 
habitat designation.
    The economic analysis further refines these numbers by estimating 
the incremental impacts of the critical habitat designation. The 
incremental impacts are forecast to be $501,000 (discounted at three 
percent) over 20 years. These incremental impacts are of additional 
administrative effort in considering adverse modification in section 7 
consultation.
    Because our economic analysis did not identify any disproportionate 
costs resulting from the designation, we did not consider excluding any 
areas from this designation of critical habitat based on economic 
impacts.
    A copy of the final economic analysis with supporting documents may 
be obtained by contacting U.S. Fish and Wildlife Service, Branch of 
Endangered Species (see FOR FURTHER INFORMATION CONTACT) or by 
downloading from the Internet at http://www.fws.gov/panamacity/.

Other Relevant Impacts

    Under section 4(b)(2) of the Act, we must consider, in addition to 
economic impacts, all other relevant impacts resulting from critical 
habitat designation. We consider a number of factors in this part of a 
section 4(b)(2) analysis. We consider whether there are lands owned or 
managed by the Department of Defense (DOD) where a national security 
impact might exist. We also consider whether the landowners have 
developed any conservation plans for the area, or whether there are 
conservation partnerships that would be encouraged by designation, 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 designation.
    In this instance, we have determined that the lands within the 
designation of critical habitat for the seven mussels are not owned or 
managed by the Department of Defense, there are currently no habitat 
conservation plans for the seven mussels, and the designation does not 
include any Tribal lands or trust resources. We did not identify any 
social impacts that might occur based on designation. Since no ``other 
relevant factors'' apply to this designation, we are not considering 
exclusions from this final designation based on the non-economic 
impacts.
    Based on the above analysis (i.e., of the economic and other 
relevant impacts), the Service is not excluding any areas from critical 
habitat designation under section 4(b)(2) of the Act.

Required Determinations

Regulatory Planning and Review

    In accordance with Executive Order 12866, this document is a 
significant rule because it may raise legal and policy issues. Based on 
our economic analysis, the estimate of total potential future costs 
associated with conservation efforts for the seven mussels in areas 
designated is $83.1 million to 135.0 million over the next 20 years 
(undiscounted). The present value of these impacts is $62.3 million to 
101.0 million, using a discounted rate of three percent, or $45.0 
million to 71.7 million, using a discount rate of seven percent. The 
annualized value of these impacts is $4.13 million to $6.70 million, 
using a discount rate of three percent, or $4.13 million to 6.60 
million, using a discount rate of seven percent. Therefore, we do not 
believe that the designation of critical habitat for the seven mussels 
would result in an annual effect on the economy of $100 million or more 
or affect the economy in a material way. Due to the timeline for 
publication in the Federal Register, the Office of Management and 
Budget (OMB) has not formally reviewed the rule or accompanying 
economic analysis.
    Further, Executive Order 12866 directs Federal Agencies 
promulgating regulations to evaluate regulatory alternatives (Office of 
Management and Budget, Circular A-4, September 17, 2003). Pursuant to 
Circular A-4, once it has been determined that the Federal regulatory 
action is appropriate, the agency will need to consider alternative 
regulatory approaches. Because the determination of critical habitat is 
a statutory requirement under the ACT, we must then evaluate 
alternative regulatory approaches, where feasible, when promulgating a 
designation of critical habitat.
    In developing our designations of critical habitat, we consider 
economic impacts, impacts to national security, and other relevant 
impacts pursuant to section 4(b)(2) of the Act. Based on the

[[Page 64312]]

discretion allowable under this provision, we may exclude any 
particular area from the designation of critical habitat providing that 
the benefits of such exclusion outweigh the benefits of specifying the 
area as critical habitat and that such exclusion would not result in 
the extinction of the species. As such, we believe that the evaluation 
of the inclusion or exclusion of particular areas, or combination 
thereof, in a designation constitutes our regulatory alternative 
analysis.

Regulatory Flexibility Act (5 U.S.C. 601 et seq.)

    Under the Regulatory Flexibility Act (5 U.S.C. 601 et seq., as 
amended by the Small Business Regulatory Enforcement Fairness Act 
(SBREFA) of 1996), whenever an agency is required to 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 effect 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 an agency 
certifies the rule will not have a significant economic impact on a 
substantial number of small entities. The SBREFA amended the RFA to 
require Federal agencies to provide a statement of factual basis for 
certifying that the rule will not have a significant economic impact on 
a substantial number of small entities.
    Small entities include small organizations, such as independent 
nonprofit organizations; small governmental jurisdictions, including 
school boards and city and town governments that serve fewer than 
50,000 residents; as well as small businesses. Small businesses include 
manufacturing and mining concerns with fewer than 500 employees, 
wholesale trade entities with fewer than 100 employees, retail and 
service businesses with less than $5 million in annual sales, general 
and heavy construction businesses with less than $27.5 million in 
annual business, special trade contractors doing less than $11.5 
million in annual business, and agricultural businesses with annual 
sales less than $750,000. To determine if potential economic impacts to 
these small entities are significant, we consider the types of 
activities that might trigger regulatory impacts under this rule, as 
well as the types of project modifications that may result. In general, 
the term ``significant economic impact'' is meant to apply to a typical 
small business firm's business operations.
    To determine if the rule could significantly affect a substantial 
number of small entities, we consider the number of small entities 
affected within particular types of economic activities (such as 
housing development, grazing, oil and gas production, timber 
harvesting). We apply the ``substantial number'' test individually to 
each industry to determine if certification is appropriate. However, 
the SBREFA does not explicitly define ``substantial number'' or 
``significant economic impact.'' Consequently, to assess whether a 
``substantial number'' of small entities is affected by this 
designation, this analysis considers the relative number of small 
entities likely to be impacted in an area. In some circumstances, 
especially with critical habitat designations of limited extent, we may 
aggregate across all industries and consider whether the total number 
of small entities affected is substantial. In estimating the number of 
small entities potentially affected, we also consider whether their 
activities have any Federal involvement.
    Designation of critical habitat only affects activities conducted, 
funded, or permitted by Federal agencies. Some kinds of activities are 
unlikely to have any Federal involvement and so will not be affected by 
critical habitat designation. In areas where the species is present, 
Federal agencies already are required to consult with us under section 
7 of the Act on activities they fund, permit, or implement that may 
affect the seven mussels. Federal agencies also must consult with us if 
their activities may affect critical habitat. Designation of critical 
habitat, therefore, could result in an additional economic impact on 
small entities due to the requirement to reinitiate consultation for 
ongoing Federal activities.
    We conducted a Final Regulatory Impact Assessment for this rule, 
and our FRIA concludes that, of the land use activities considered in 
sections 3 to 6 of this analysis, incremental impacts of critical 
habitat designation to the following activities may be borne by small 
entities:
     Water management; and
     Deadhead logging.
    Water management effects may occur to one hydropower operation, and 
result in costs of approximately $1000 for the additional burden of 
consultation that considers critical habitat. Deadhead logging impacts 
may affect 10 businesses, for an estimated impact of $3800 per 
business. We do not consider these effects to be substantial.
    In summary, we have considered whether this would result in a 
significant economic effect on a substantial number of small entities. 
We have determined, for the above reasons and based on currently 
available information, that it will not affect a substantial number of 
small entities.

Small Business Regulatory Enforcement Fairness Act (5 U.S.C. 801 et 
seq.)

    Under SBREFA, this rule is not a major rule. Our detailed 
assessment of the economic effects of this designation is described in 
the economic analysis. Based on the effects identified in the economic 
analysis, we believe that this rule will not have an annual effect on 
the economy of $100 million or more, will not cause a major increase in 
costs or prices for consumers, and will not have significant adverse 
effects on competition, employment, investment, productivity, 
innovation, or the ability of U.S.-based enterprises to compete with 
foreign-based enterprises. Refer to the final economic analysis for a 
discussion of the effects of this determination.

Executive Order 13211

    On May 18, 2001, the President issued Executive Order 13211 
(Actions Concerning Regulations That Significantly Affect Energy 
Supply, Distribution, or Use) on regulations that significantly affect 
energy supply, distribution, and use. Executive Order 13211 requires 
agencies to prepare Statements of Energy Effects when undertaking 
certain actions. This final rule to designate critical habitat for the 
seven mussels is not expected to significantly affect energy supplies, 
distribution, or use. Therefore, this action is not a significant 
energy action, and no Statement of Energy Effects is required.

Unfunded Mandates Reform Act (2 U.S.C. 1501 et seq.)

    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

[[Page 64313]]

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; AFDC 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 who receive Federal 
funding, assistance, permits or 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 because it will not produce a Federal mandate 
of $100 million or greater in any year; that is, it is not a 
``significant regulatory action'' under the Unfunded Mandates Reform 
Act. The designation of critical habitat imposes no obligations on 
State or local governments. As such, a Small Government Agency Plan is 
not required.

Takings

    In accordance with Executive Order 12630 (``Government Actions and 
Interference with Constitutionally Protected Private Property 
Rights''), we have analyzed the potential takings implications of 
designating 1,908.5 river km (1,185.9 river mi) in portions of Alabama, 
Florida, and Georgia as critical habitat for the seven mussels in a 
takings implications assessment. The takings implications assessment 
concludes that this final designation of critical habitat does not pose 
significant takings implications for lands within or affected by the 
designation.

Federalism

    In accordance with Executive Order 13132 (Federalism), the rule 
does not have significant Federalism effects. A Federalism assessment 
is not required. In keeping with the Department of the Interior and 
Department of Commerce policy, we requested information from, and 
coordinated development of, this final critical habitat designation 
with appropriate State resource agencies in Alabama, Florida, and 
Georgia. The designation of critical habitat in areas currently 
occupied by the seven mussels may impose additional regulatory 
restrictions to those currently in place and, therefore, may have some 
incremental impact on State and local governments and their activities. 
The designation also may have some benefit to these governments in that 
the areas that contain the features essential to the conservation of 
the species are more clearly defined, and the PCEs of the habitat 
necessary to the conservation of the species are specifically 
identified. While making this definition and identification does not 
alter where and what federally sponsored activities may occur, it may 
assist these local governments in long-range planning (rather than 
waiting for case-by-case section 7 consultations to occur).

Civil Justice Reform

    In accordance with Executive Order 12988 (Civil Justice Reform), 
the Office of the Solicitor has determined that the rule does not 
unduly burden the judicial system and meets the requirements of 
sections 3(a) and 3(b)(2) of the Order. We are designating critical 
habitat in accordance with the provisions of the Endangered Species 
Act. This final rule uses standard property descriptions and identifies 
the PCEs within the designated areas to assist the public in 
understanding the habitat needs of the seven mussels.

Paperwork Reduction Act of 1995 (44 U.S.C. 3501 et seq.)

    This rule does not contain any new collections of information that 
require approval by OMB under the Paperwork Reduction Act. 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) (42 U.S.C. 4321 et. seq.)

    It is our position that, outside the Jurisdiction of the Tenth 
Federal Circuit, we do not need to prepare environmental analyses as 
defined by NEPA in connection with designating critical habitat under 
the Endangered Species Act of 1973, as amended. We published a notice 
outlining our reasons for this determination in the Federal Register on 
October 25, 1983 (48 FR 49244). This assertion was upheld in the courts 
of the Ninth Circuit (Douglas County v. Babbitt, 48 F.3d 1495 (9th Cir. 
Ore. 1995), cert. denied 516 U.S. 1042 (1996)).

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), Executive Order 13175, and the Department 
of 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 that were occupied by the seven mussels at the time of 
listing containing the features essential for their conservation, and 
no Tribal lands that are unoccupied by the seven mussels but are 
essential for their conservation. Therefore, critical habitat for the 
seven mussels has not been designated on tribal lands.

[[Page 64314]]

References Cited

    A complete list of all references cited in this rulemaking is 
available upon request from the Field Supervisor, Panama City 
Ecological Services Office (see ADDRESSES).

Author(s)

    The primary author of this package is staff of the Panama City 
Ecological Services Office.

List of Subjects in 50 CFR Part 17

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

Regulation Promulgation

0
Accordingly, we amend part 17, subchapter B of chapter I, title 50 of 
the Code of Federal Regulations, as set forth below:

PART 17--[AMENDED]

0
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.

0
2. In Sec.  17.11(h), revise the entries for ``Bankclimber, purple 
(mussel),'' ``Moccasinshell, Gulf,'' ``Moccasinshell, Ochlockonee,'' 
``Pigtoe, oval,'' ``Pocketbook, shinyrayed,'' ``Slabshell, Chipola,'' 
and ``Threeridge, fat (mussel),'' under ``CLAMS'' to read as follows:


Sec.  17.11  Endangered and threatened wildlife.

* * * * *
    (h) * * *

--------------------------------------------------------------------------------------------------------------------------------------------------------
                         Species                                                  Vertebrate population
----------------------------------------------------------    Historic  range      where endangered  or      Status         When     Critical   Special
            Common name                Scientific name                                  threatened                         listed    habitat     rules
--------------------------------------------------------------------------------------------------------------------------------------------------------
 
                                                                      * * * * * * *
               Clams
 
                                                                      * * * * * * *
Bankclimber, purple (mussel)......  Elliptoideus           U.S.A. (AL, FL, GA)..  NA...................  T                     633   17.95(f)         NA
                                     sloatianus.
 
                                                                      * * * * * * *
Moccasinshell, Gulf...............  Medionidus             U.S.A. (AL, FL, GA)..  NA...................  E                     633   17.95(f)         NA
                                     penicillatus.
 
                                                                      * * * * * * *
Moccasinshell, Ochlockonee........  Medionidus             U.S.A. (FL, GA)......  NA...................  E                     633   17.95(f)         NA
                                     simpsonianus.
 
                                                                      * * * * * * *
Pigtoe, oval......................  Pleurobema pyriforme.  U.S.A. (AL, FL, GA)..  NA...................  E                     633   17.95(f)         NA
 
                                                                      * * * * * * *
Pocketbook, shinyrayed............  Lampsilis subangulata  U.S.A. (AL, FL, GA)..  NA...................  E                     633   17.95(f)         NA
 
                                                                      * * * * * * *
Slabshell, Chipola................  Elliptio chipolaensis  U.S.A. (AL, FL)......  NA...................  T                     633   17.95(f)         NA
 
                                                                      * * * * * * *
Threeridge, fat (mussel)..........  Amblema neislerii....  U.S.A. (FL, GA)......  NA...................  E                     633   17.95(f)         NA
 
                                                                      * * * * * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------


0
3. In Sec.  17.95, at the end of paragraph (f), add an entry for seven 
mussel species (in four northeast Gulf of Mexico drainages) to read as 
follows:


Sec.  17.95  Critical habitat--fish and wildlife.

* * * * *
    (f) Clams and snails.
* * * * *
    Seven mussel species (in four northeast Gulf of Mexico drainages): 
Purple bankclimber (Elliptoideus sloatianus), Gulf moccasinshell 
(Medionidus penicillatus), Ochlockonee moccasinshell (Medionidus 
simpsonianus), oval pigtoe (Pleurobema pyriforme), shinyrayed 
pocketbook (Lampsilis subangulata), Chipola slabshell (Elliptio 
chipolaensis), and fat threeridge (Amblema neislerii).
    (1) Critical habitat units are depicted on the maps below for the 
following counties:
    (i) Alabama: Houston and Russell;
    (ii) Florida: Alachua, Bay, Bradford, Calhoun, Columbia, Franklin, 
Gadsden, Gulf, Jackson, Leon, Liberty, Union, Wakulla, and Washington; 
and
    (iii) Georgia: Baker, Calhoun, Coweta, Crawford, Crisp, Decatur, 
Dooly, Dougherty, Early, Fayette, Grady, Lee, Macon, Marion, 
Meriwether, Miller, Mitchell, Peach, Pike, Schley, Spalding, Sumter, 
Talbot, Taylor, Terrell, Thomas, Upson, Webster, and Worth.
    (2) The primary constituent elements of critical habitat for the 
purple bankclimber (Elliptoideus sloatianus), Gulf moccasinshell 
(Medionidus penicillatus), Ochlockonee moccasinshell (Medionidus 
simpsonianus), oval pigtoe (Pleurobema pyriforme), shinyrayed 
pocketbook (Lampsilis subangulata), Chipola slabshell (Elliptio 
chipolaensis), and fat threeridge (Amblema neislerii) are:
    (i) A geomorphically stable stream channel (a channel that 
maintains its lateral dimensions, longitudinal profile, and spatial 
pattern over time without a consistent aggrading or degrading bed 
elevation);
    (ii) A predominantly sand, gravel, and/or cobble stream substrate 
with low to moderate amounts of silt and clay;
    (iii) Permanently flowing water;

[[Page 64315]]

    (iv) Water quality (including temperature, turbidity, dissolved 
oxygen, and chemical constituents) that meets or exceeds the current 
aquatic life criteria established under the Clean Water Act (33 U.S.C. 
1251-1387); and
    (v) Fish hosts (such as largemouth bass, sailfin shiner, brown 
darter) that support the larval life stages of the seven mussels.
    (3) Critical habitat does not include manmade structures (such as 
buildings, aqueducts, airports, 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 and not containing one or more of the 
primary constituent elements.
    (4) Critical habitat unit maps. Data layers defining map units were 
created with USGS National Hydrography Dataset (NHD) GIS data. The 
1:100,000 river reach (route) files were used to calculate river 
kilometers and miles. The following data sources were referenced to 
identify upstream and downstream extents of critical habitat units: 
USGS 7.5' quadrangles; Georgia Department of Transportation county 
highway maps; U.S. Census Bureau 1:100,000 TIGER line road data; 1993 
Georgia digital orthographic quarter quads (DOQQs); 2004 Florida DOQQs; 
and DeLorme Atlas and Gazetteers for Alabama, Florida, and Georgia. The 
projection used in mapping all units was Universal Transverse Mercator 
(UTM), NAD 83, Zone 16 North.
    (5) Note: Index map of critical habitat units in the States of 
Alabama, Florida, and Georgia for the seven mussels follows:
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[[Page 64317]]


    (6) Table of listed species and critical habitat units. A table 
showing the listed species, their respective critical habitat units, 
and the States that contain those habitat units follows. Detailed 
critical habitat unit descriptions and maps appear below in paragraphs 
(7) through (17).

------------------------------------------------------------------------
                                  Critical habitat
            Species                    units               States
------------------------------------------------------------------------
Purple bankclimber               Units 5, 6, 7, 8,  AL, FL, GA
 (Elliptoideus sloatianus).       9, 10.
Gulf moccasinshell (Medionidus   Units 1, 2, 4, 5,  AL, FL, GA
 penicillatus).                   6, 7.
Ochlockonee moccasinshell        Unit 9...........  FL, GA
 (Medionidus simpsonianus).
Oval pigtoe (Pleurobema          Units 1, 2, 4, 5,  AL, FL, GA
 pyriforme).                      6, 7, 9, 11.
Shinyrayed pocketbook            Units 2, 3, 4, 5,  AL, FL, GA
 (Lampsilis subangulata).         6, 7, 9.
Chipola slabshell (Elliptio      Unit 2...........  AL, FL
 chipolaensis).
Fat threeridge (mussel)          Units 2, 7, 8....  AL, FL, GA
 (Amblema neislerii).
------------------------------------------------------------------------

    (7) Unit 1. Econfina and Moccasin creeks, Bay and Washington 
Counties, Florida. This is a critical habitat unit for the Gulf 
moccasinshell and oval pigtoe.
    (i) General Description: Unit 1 includes the main stem of Econfina 
Creek and one of its tributaries, Moccasin Creek, encompassing a total 
stream length of 31.4 kilometers (km) (19.5 miles (mi)). The main stem 
of Econfina Creek extends from its confluence with Deer Point Lake at 
the powerline crossing located 3.8 km (2.3 mi) downstream of Bay County 
Highway 388 (-85.56 longitude, 30.36 latitude), Bay County, Florida, 
upstream 28.6 km (17.8 mi) to Tenmile Creek (-85.50 longitude, 30.51 
latitude), Washington County, Florida; and Moccasin Creek from its 
confluence with Econfina Creek upstream 2.8 km (1.7 mi) to Ellis Branch 
(-85.53 longitude, 30.41 latitude), Bay County, Florida.
    (ii) Note: Unit 1 map follows:
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[[Page 64319]]

    (8) Unit 2. Chipola River and Dry, Rocky, Waddells Mill, Baker, 
Marshall, Big, and Cowarts Creeks in Houston County, Alabama, and in 
Calhoun, Gulf, and Jackson counties, Florida. This is a critical 
habitat unit for the fat threeridge, shinyrayed pocketbook, Gulf 
moccasinshell, oval pigtoe, and Chipola slabshell.
    (i) General Description: Unit 2 includes the main stem of the 
Chipola River and seven of its tributaries, encompassing a total stream 
length of 228.7 km (142.1 mi). The main stem of the Chipola River 
extends from its confluence with the Apalachicola River (-85.09 
longitude, 30.01 latitude) in Gulf County, Florida, upstream 144.9 
river km (90.0 river mi), including the reach known as Dead Lake, to 
the confluence of Marshall and Cowarts creeks (-85.27 longitude, 30.91 
latitude) in Jackson County, Florida; Dry Creek from the Chipola River 
upstream 7.6 river km (4.7 river mi) to Ditch Branch (-85.24 longitude, 
30.69 latitude), Jackson County, Florida; Rocky Creek from the Chipola 
River upstream 7.1 river km (4.4 river mi) to Little Rocky Creek (-
85.13 longitude, 30.68 latitude), Jackson County, Florida; Waddells 
Mill Creek from the Chipola River upstream 3.7 river km (2.3 river mi) 
to Russ Mill Creek (-85.29 longitude, 30.87 latitude), Jackson County, 
Florida; Baker Creek from Waddells Mill Creek upstream 5.3 river km 
(3.3 river mi) to Tanner Springs (-85.32 longitude, 30.83 latitude), 
Jackson County, Florida; Marshall Creek from the Chipola River upstream 
13.7 river km (8.5 river mi) to the Alabama-Florida State line (-85.33 
longitude, 31.00 latitude), Jackson County, Florida; Cowarts Creek from 
the Chipola River in Jackson County, Florida, upstream 33.5 river km 
(20.8 river mi) to the Edgar Smith Road bridge (-85.29 longitude, 31.13 
latitude), Houston County, Alabama; and Big Creek from the Alabama-
Florida State line upstream 13.0 river km (8.1 river mi) to Limestone 
Creek (-85.42 longitude, 31.08 latitude), Houston County, Alabama. The 
short segment of the Chipola River that flows underground within the 
boundaries of Florida Caverns State Park is not included within this 
unit.
    (ii) Note: Unit 2 map follows:
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[[Page 64321]]


    (9) Unit 3. Uchee Creek, Russell County, Alabama. This is a 
critical habitat unit for the shinyrayed pocketbook.
    (i) General Description: Unit 3 includes the main stem of Uchee 
Creek from its confluence with the Chattahoochee River upstream 34.2 km 
(21.2 mi) to Island Creek (-85.18 longitude, 32.38 latitude), Russell 
County, Alabama, encompassing a total stream length of 34.2 km (21.2 
mi).
    (ii) Note: Unit 3 map follows:
    [GRAPHIC] [TIFF OMITTED] TR15NO07.003
    

[[Page 64322]]


    (10) Unit 4. Sawhatchee, Sheffield Mill, and Kirkland creeks, Early 
County, Georgia. This is a critical habitat unit for the shinyrayed 
pocketbook, Gulf moccasinshell, and oval pigtoe.
    (i) General Description: Unit 4 includes the main stems of 
Sawhatchee and Kirkland creeks, and one tributary, encompassing a total 
stream length of 37.8 km (23.5 mi). Unit 4 includes Sawhatchee Creek 
from its confluence with the Chattahoochee River upstream 28.6 km (17.8 
mi) to the powerline crossing located 1.4 km (0.87 mi) upstream of 
Early County Road 15 (-84.99 longitude, 31.32 latitude); Sheffield Mill 
Creek, the tributary, from its confluence with Sawhatchee Creek 
upstream 3.1 km (1.9 mi) to the powerline crossing located 2.3 km (1.4 
mi) upstream of Sowhatchee Road (-85.01 longitude, 31.23 latitude); 
Kirkland Creek from its confluence with the Chattahoochee River 
upstream 6.1 km (3.8 mi) to Dry Creek (-85.00 longitude, 31.13 
latitude).
    (ii) Note: Unit 4 map follows:
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[[Page 64324]]

    (11) Unit 5. Upper Flint River and Swift, Limestone, Turkey, 
Pennahatchee, Little Pennahatchee, Hogcrawl, Red Oak, Line, and 
Whitewater creeks in Coweta, Crawford, Crisp, Dooly, Fayette, Macon, 
Meriwether, Peach, Pike, Spalding, Sumter, Talbot, Taylor, Upson, and 
Worth counties, Georgia. This is a critical habitat unit for the 
shinyrayed pocketbook, Gulf moccasinshell, oval pigtoe, and purple 
bankclimber.
    (i) General Description: Unit 5 encompasses a total stream length 
of 380.4 km (236.4 mi) and includes the Flint River from the State 
Highway 27 bridge (Vienna Road) (-83.98 longitude, 32.06 latitude) in 
Dooly and Sumter counties, Georgia (the river is the county boundary), 
upstream 247.4 km (153.7 mi) through Macon, Peach, Taylor, Crawford, 
Talbot, Upson, Pike, Meriwether, and Coweta counties, to Horton Creek 
(-84.42 longitude, 33.29 latitude) in Fayette and Spalding counties, 
Georgia (the river is the county boundary); Swift Creek from Lake 
Blackshear upstream 11.3 km (7 mi) to Rattlesnake Branch (-83.84 
longitude, 31.82 latitude), Crisp and Worth counties, Georgia (the 
creek is the county boundary); Limestone Creek from Lake Blackshear, 
Crisp County, Georgia, upstream 8.8 km (5.5 mi) to County Road 89 (-
83.88 longitude, 32.04 latitude), Dooly County, Georgia; Turkey Creek 
from the Flint River upstream 21.7 km (13.5 mi) to Rogers Branch (-
83.89 longitude, 32.20 latitude), in Dooly County, Georgia; 
Pennahatchee Creek from Turkey Creek upstream 4.8 km (3 mi) to Little 
Pennahatchee Creek (-83.89 longitude, 32.10 latitude), Dooly County, 
Georgia; Little Pennahatchee Creek from Pennahatchee Creek upstream 5.8 
km (3.6 mi) to Rock Hill Creek (-83.85 longitude, 32.13 latitude), 
Dooly County, Georgia; Hogcrawl Creek from the Flint River upstream 
21.6 km (13.4 mi) to Little Creek (-83.90 longitude, 32.28 latitude), 
Dooly and Macon counties, Georgia (the creek is the county boundary); 
Red Oak Creek from the Flint River upstream 21.7 km (13.5 mi) to 
Brittens Creek (-84.68 longitude, 33.11 latitude), Meriwether County, 
Georgia; Line Creek from the Flint River upstream 15.8 km (9.8 mi) to 
Whitewater Creek (-84.51 longitude, 33.28 latitude), Coweta and Fayette 
counties, Georgia (the creek is the county boundary); and Whitewater 
Creek from Line Creek upstream 21.5 km (13.4 mi) to Ginger Cake Creek 
(-84.49 longitude, 33.42 latitude), Fayette County, Georgia.
    (ii) Note: Two maps of unit 5--northern part of unit 5 and--
southern part of unit 5 follow:
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[[Page 64326]]


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[[Page 64327]]

    (12) Unit 6. Middle Flint River and Kinchafoonee, Lanahassee, 
Muckalee, Little Muckalee, Mill, Mercer Mill Pond, Abrams, Jones, and 
Chokee creeks in Dougherty, Lee, Marion, Schley, Sumter, Terrell, 
Webster, and Worth counties, Georgia. This is a critical habitat unit 
for the shinyrayed pocketbook, Gulf moccasinshell, oval pigtoe, and 
purple bankclimber.
    (i) General Description: Unit 6 encompasses a total stream length 
of 302.3 km (187.8 mi) and includes the Flint River from Piney Woods 
Creek (-84.06 longitude, 31.61 latitude) in Dougherty County, Georgia 
(the upstream extent of Lake Worth), upstream 39.9 km (24.8 mi) to the 
Warwick Dam (-83.94 longitude, 31.85 latitude), Lee and Worth counties, 
Georgia; Kinchafoonee Creek from its confluence with Lake Worth at the 
Lee--Dougherty county line (-84.17 longitude, 31.62 latitude), upstream 
107.6 km (66.8 mi) through Terrell and Sumter Counties, Georgia, to Dry 
Creek (-84.58 longitude, 32.17 latitude), Webster County, Georgia; 
Lanahassee Creek from Kinchafoonee Creek upstream 9.3 km (5.8 mi) to 
West Fork Lanahassee Creek (-84.50 longitude, 32.11 latitude), Webster 
County, Georgia; Muckalee Creek, from its confluence with Lake Worth at 
the Lee--Dougherty county line (-84.14 longitude, 31.62 latitude), 
upstream 104.5 km (64.9 mi) to County Road 114 (-84.44 longitude, 32.23 
latitude), Marion County, Georgia; Little Muckalee Creek, from Muckalee 
Creek in Sumter County, Georgia, upstream 7.2 km (4.5 mi) to Galey 
Creek (-84.29 longitude, 32.17 latitude), Schley County, Georgia; Mill 
Creek from the Flint River upstream 3.2 km (2 mi) to Mercer Millpond 
Creek (-83.99 longitude, 31.67 latitude), Worth County, Georgia; Mercer 
Millpond Creek from Mill Creek upstream 0.45 km (0.28 mi) to Mercer 
Mill Pond (-83.99 longitude, 31.68 latitude), Worth County, Georgia; 
Abrams Creek from the Flint River upstream 15.9 km (9.9 mi) to County 
Road 123 (-83.93 longitude, 31.68 latitude), Worth County, Georgia; 
Jones Creek from the Flint River upstream 3.8 km (2.4 mi) to County 
Road 123 (-83.96 longitude, 31.76 latitude), Worth County, Georgia; and 
Chokee Creek, from the Flint River upstream 10.5 km (6.5 mi) to Dry 
Branch Creek (-84.02 longitude, 31.89 latitude), Lee County, Georgia.
    (ii) Note: Two maps of unit 6--western part of unit 6 and--eastern 
part of unit 6 follow:
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[[Page 64330]]

    (13) Unit 7. Lower Flint River and Spring, Aycocks, Dry, 
Ichawaynochaway, Mill, Pachitla, Little Pachitla, Chickasawhatchee, and 
Cooleewahee creeks in Baker, Calhoun, Decatur, Dougherty, Early, 
Miller, Mitchell, and Terrell counties, Georgia. This is a critical 
habitat unit for the fat threeridge, shinyrayed pocketbook, Gulf 
moccasinshell, oval pigtoe, and purple bankclimber.
    (i) General Description: Unit 7 encompasses a total stream length 
of 396.7 km (246.5 mi) and includes the Flint River from its confluence 
with Big Slough (-84.56 longitude, 30.93 latitude), Decatur County, 
Georgia, upstream 116.4 km (72.3 mi) through Baker and Mitchell 
Counties, Georgia, to the Flint River Dam (which impounds Lake Worth) 
(-84.14 longitude, 31.60 latitude), Dougherty County, Georgia; Spring 
Creek, from its confluence with Lake Seminole at Smith Landing (-84.75 
longitude, 30.89 latitude), Decatur County, Georgia, upstream 74.2 km 
(46.1 mi) to County Road 35 (-84.78 longitude, 31.34 latitude), Early 
County, Georgia; Aycocks Creek from Spring Creek upstream 15.9 km (9.9 
mi) to Cypress Creek (-84.79 longitude, 31.15 latitude), Miller County, 
Georgia; Dry Creek from Spring Creek upstream 9.9 km (6.1 mi) to Wamble 
Creek (-84.84 longitude, 31.31 latitude), Early County, Georgia; 
Ichawaynochaway Creek from the Flint River, Baker County, Georgia, 
upstream 68.6 km (42.6 mi) to Merrett Creek (-84.58 longitude, 31.54 
latitude), Calhoun County, Georgia; Mill Creek from Ichawaynochaway 
Creek upstream 7.4 km (4.6 mi) to County Road 163 (-84.63 longitude, 
31.40 latitude), Baker County, Georgia; Pachitla Creek, from 
Ichawaynochaway Creek upstream 18.9 km (11.8 mi) to Little Pachitla 
Creek (-84.68 longitude, 31.56 latitude), Calhoun County, Georgia; 
Little Pachitla Creek from Pachitla Creek upstream 5.8 km (3.6 mi) to 
Bear Branch (-84.72 longitude, 31.58 latitude), Calhoun County, 
Georgia; Chickasawhatchee Creek from Ichawaynochaway Creek, Baker 
County, Georgia, upstream 64.5 km (40.1 mi) to U.S. Highway 82 (-84.38 
longitude, 31.74 latitude), Terrell County, Georgia; and Cooleewahee 
Creek from the Flint River upstream 15.1 km (9.4 mi) to Piney Woods 
Branch (-84.31 longitude, 31.42 latitude), Baker County, Georgia.
    (ii) Note: Two maps of unit 7--western part of unit 7 and--eastern 
part of unit 7 follow:
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[[Page 64333]]

    (14) Unit 8. Apalachicola River, Chipola Cutoff, Swift Slough, 
River Styx, Kennedy Slough, and Kennedy Creek in Calhoun, Franklin, 
Gadsden, Gulf, Jackson, and Liberty Counties, Florida. This is a 
critical habitat unit for the fat threeridge and purple bankclimber.
    (i) General Description: Unit 8 includes the main stem of the 
Apalachicola River, two of its distributaries, Chipola Cutoff and Swift 
Slough, and three of its tributaries, River Styx, Kennedy Slough, and 
Kennedy Creek, encompassing a total length of 161.2 river km (100.2 
river mi). The main stem of the Apalachicola River extends from the 
downstream end of Bloody Bluff Island (river mile 15.3 on U.S. Army 
Corps of Engineers Navigation Charts) (-85.01 longitude, 29.88 
latitude), Franklin County, Florida, through Calhoun and Liberty 
Counties, Florida, upstream to the Jim Woodruff Lock and Dam (which 
impounds Lake Seminole) (-84.86 longitude, 30.71 latitude), Gadsden and 
Jackson Counties, Florida; Chipola Cutoff from the Apalachicola River 
in Gulf County, Florida, downstream 4.5 river km (2.8 river mi) to its 
confluence with the Chipola River; Swift Slough from the Apalachicola 
River in Liberty County, Florida, downstream 3.6 river km (2.2 river 
mi) to its confluence with the River Styx (-85.12 longitude, 30.10 
latitude); River Styx from the mouth of Swift Slough (-85.12 longitude, 
30.10 latitude) in Liberty County, Florida, downstream 3.8 river km 
(2.4 river mi) to its confluence with the Apalachicola River; Kennedy 
Slough from -85.07 longitude, 30.01 latitude in Liberty County, 
Florida, downstream 0.9 river km (0.5 river mi) to its confluence with 
Kennedy Creek; and Kennedy Creek from Brushy Creek Feeder (-85.06 
longitude, 30.01 latitude) in Liberty County, Florida, downstream 1.1 
river km (0.7 river mi) to its confluence with the Apalachicola River.
    (ii) Note: Unit 8 map follows:
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    (15) Unit 9. Upper Ochlockonee River and Barnetts and West Barnetts 
creeks, and the Little Ochlockonee River in Gadsden and Leon counties, 
Florida, and in Grady and Thomas counties, Georgia. This is a critical 
habitat unit for the shinyrayed pocketbook, Ochlockonee moccasinshell, 
oval pigtoe, and purple bankclimber.
    (i) General Description: Unit 9 includes the main stem of the 
Ochlockonee River upstream of Lake Talquin and three tributaries 
encompassing a total stream length of 177.3 km (110.2 mi). The main 
stem of the Ochlockonee River extends from its confluence with Gulley 
Branch (the approximate upstream extent of Lake Talquin) (-84.44 
longitude, 30.46 latitude), Gadsden and Leon counties, Florida, 
upstream 134.0 km (83.3 mi) to Bee Line Road/County Road 306 (-83.94 
longitude, 31.03 latitude), Thomas County, Georgia; Barnetts Creek from 
the Ochlockonee River upstream 20 km (12.4 mi) to Grady County Road 
170/Thomas County Road 74 (-84.12 longitude, 30.98 latitude), Grady and 
Thomas counties, Georgia; West Barnetts Creek from Barnetts Creek 
upstream 10 km (6.2 mi) to Georgia Highway 111 (-84.17 longitude, 30.98 
latitude), Grady County, Georgia; and the Little Ochlockonee River from 
the Ochlockonee River upstream 13.3 km (8.3 mi) to Roup Road/County 
Road 33 (-84.02 longitude, 31.02 latitude), Thomas County, Georgia.
    (ii) Note: Unit 9 map follows:
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    (16) Unit 10. Lower Ochlockonee River in Leon, Liberty, and Wakulla 
counties, Florida. This is a critical habitat unit for the purple 
bankclimber.
    (i) General Description: Unit 10 encompasses a total stream length 
of 75.4 km (46.9 mi) and includes the main stem of the Ochlockonee 
River from its confluence with Syfrett Creek (-84.56 longitude, 30.02 
latitude), Wakulla County, Florida, upstream 75.4 km (46.9 mi) to the 
Jackson Bluff Dam (which impounds Lake Talquin) (-84.65 longitude, 
30.39 latitude), Leon and Liberty counties, Florida.
    (ii) Note: Unit 10 map follows:

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    (17) Unit 11. Santa Fe River and New River in Alachua, Bradford, 
Columbia, and Union counties, Florida. This is a critical habitat unit 
for the oval pigtoe.
    (i) General Description: Unit 11 includes the main stem of the 
Santa Fe River and its tributary the New River encompassing a total 
stream length of 83.1 km (51.6 mi). The main channel of the Santa Fe 
River extends from where the river goes underground in O'Leno State 
Park (-82.57 longitude, 29.91 latitude), Alachua and Columbia counties, 
Florida, upstream 60.2 km (37.4 mi) to the powerline crossing located 
1.9 km (1.2 mi) downstream from the U.S. Highway 301 bridge (-82.18 
longitude, 29.84 latitude) in Alachua and Bradford counties, Florida; 
and the New River from its confluence with the Santa Fe River at the 
junction of Alachua, Bradford, and Union counties, Florida, upstream 
22.9 km (14.2 mi) to McKinney Branch (-82.27 longitude, 30.01 latitude) 
in Bradford and Union counties, Florida.
    (ii) Note: Unit 11 map follows:

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* * * * *

    Dated: October 31, 2007.
David M. Verhey,
Acting Assistant Secretary for Fish and Wildlife and Parks.
[FR Doc. 07-5551 Filed 11-14-07; 8:45 am]
BILLING CODE 4310-55-C