[Federal Register Volume 74, Number 123 (Monday, June 29, 2009)]
[Proposed Rules]
[Pages 31114-31151]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E9-15236]



[[Page 31113]]

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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; Proposed Endangered 
Status for the Georgia Pigtoe Mussel, Interrupted Rocksnail, and Rough 
Hornsnail with Critical Habitat; Proposed Rule

Federal Register / Vol. 74, No. 123 / Monday, June 29, 2009 / 
Proposed Rules

[[Page 31114]]


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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

[FWS-R4-ES-2008-0104; MO 9221050083]
RIN 1018-AU88


Endangered and Threatened Wildlife and Plants; Proposed 
Endangered Status for the Georgia Pigtoe Mussel, Interrupted Rocksnail, 
and Rough Hornsnail with Critical Habitat

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Proposed rule.

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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), propose to 
list the Georgia pigtoe mussel (Pleurobema hanleyianum), interrupted 
rocksnail (Leptoxis foremani), and rough hornsnail (Pleurocera 
foremani), as endangered species under the Endangered Species Act of 
1973, as amended (Act). The Georgia pigtoe, interrupted rocksnail, and 
rough hornsnail are endemic to the Coosa River drainage within the 
Mobile River Basin of Alabama, Tennessee, and Georgia. These three 
species have disappeared from large portions of their natural ranges 
due to extensive construction of dams that eliminated or reduced water 
currents and caused changes in habitat and water quality. The surviving 
populations are small, localized, and highly vulnerable to water 
quality and habitat deterioration.
    We are also proposing to designate critical habitat concurrently 
for the Georgia pigtoe, interrupted rocksnail, and rough hornsnail 
under the Act. In total, approximately 258 kilometers (km) (160 miles 
(mi)) of stream and river channels fall within the boundaries of the 
proposed critical habitat designation for the three species: 153 km (95 
mi) for the Georgia pigtoe, 101 km (63 mi) for the interrupted 
rocksnail, and 27.4 km (17 mi) for the rough hornsnail. The proposed 
critical habitat is located in Cherokee, Clay, Coosa, Elmore, and 
Shelby Counties, Alabama; Gordon, Floyd, Murray, and Whitfield 
Counties, Georgia; and Bradley and Polk Counties, Tennessee.
    These proposals, if made final, would implement Federal protection 
provided by the Act.

DATES: We will accept comments received on or before August 28, 2009. 
We must receive requests for public hearings, in writing, at the 
address shown in the FOR FURTHER INFORMATION CONTACT section by August 
13, 2009.

ADDRESSES: You may submit comments by one of the following methods:
    <bullet<ls-thn-eq> Federal eRulemaking Portal: http://www.regulations.gov. Follow the instructions for submitting comments.
    <bullet> U.S. mail or hand-delivery: Public Comments Processing, 
Attn: RIN 1018-AU88; Division of Policy and Directives Management; U.S. 
Fish and Wildlife Service; 4401 N. Fairfax Drive, Suite 222; Arlington, 
VA 22203.
    We will not accept e-mail or faxes. We will post all comments on 
http://www.regulations.gov. This generally means that we will post any 
personal information you provide us (see the Public Comments section 
below for more information).

FOR FURTHER INFORMATION CONTACT: Cary Norquist, Acting Field 
Supervisor, Mississippi Fish and Wildlife Office at 6578 Dogwood View 
Parkway, Suite A, Jackson, MS 39213 (telephone 601-321-1122; facsimile 
601-965-4340). If you use a telecommunications device for the deaf 
(TDD), you may call the Federal Information Relay Service (FIRS) at 
800-877-8339.

SUPPLEMENTARY INFORMATION:

Public Comments

    We intend that any final action resulting from this proposal will 
be as accurate and as effective as possible. Therefore, we are seeking 
comments or suggestions from the public, other concerned governmental 
agencies, the scientific community, industry, or any other interested 
party concerning this proposed rule. We particularly seek comments 
concerning:
    (1) Any biological, commercial trade, or other relevant data 
concerning any threat (or lack thereof) to the Georgia pigtoe mussel, 
interrupted rocksnail, and rough hornsnail;
    (2) Any additional information concerning the ranges, 
distributions, and population sizes of the species;
    (3) Land use designations and current or planned activities in the 
subject area and their possible impacts on these species or proposed 
critical habitats;
    (4) The reasons why any area should or should not be designated as 
critical habitat as provided by section 4 of the Act (16 U.S.C. 1531 et 
seq.), including whether the benefit of designation would outweigh 
threats to the species caused by designation such that the designation 
of critical habitat is prudent;
    (5) Specific information on the amount and distribution of habitat 
for the Georgia pigtoe, interrupted rocksnail, and rough hornsnail, 
including areas occupied at the time of listing and containing the 
features essential to the conservation of the species, and areas not 
occupied at the time of listing that are essential to the conservation 
of the species and why;
    (6) Any foreseeable economic, national security, or other potential 
impacts resulting from the proposed designation and, in particular, any 
impacts on small entities, and information about the benefits of 
including or excluding any areas that exhibit those impacts; and
    (7) Whether our approach to designating critical habitat could be 
improved or modified in any way to provide for greater public 
participation and understanding, or to assist us in accommodating 
public concerns and comments.
    You may submit your comments and materials concerning this proposed 
rule by one of the methods listed in the ADDRESSES section. We will not 
accept comments you send by e-mail or fax or to an address not listed 
in the ADDRESSES section.
    We will post your entire comment--including your personal 
identifying information--on http://www.regulations.gov. If you provide 
personal identifying information in addition to the required items 
specified in the previous paragraph, such as your street address, phone 
number, or e-mail address, you may request at the top of your document 
that we withhold this information from public review. However, we 
cannot guarantee that we will be able to do so.
    Comments and materials we receive, as well as supporting 
documentation we used in preparing this proposed rule, will be 
available for public inspection on http://www.regulations.gov, or by 
appointment, during normal business hours, at the U.S. Fish and 
Wildlife Service, Mississippi Fish and Wildlife Office (see FOR FURTHER 
INFORMATION CONTACT).

Background

Georgia Pigtoe Mussel
    The Georgia pigtoe (Pleurobema hanleyianum) is a freshwater mussel 
in the family Unionidae. It was described in 1852 by I. Lea as Unio 
hanleyianum from the Coosawattee River in Georgia. It was placed in the 
genus Pleurobema by Simpson in 1900. The uniqueness of the Georgia 
pigtoe has been verified both morphologically (Williams et al. 2008, p. 
533) and genetically (Campbell et al. 2008, pp. 719-721).
    The shell of the Georgia pigtoe reaches about 50 to 65 millimeters 
(mm) (2 to 2.5 inches (in)) in length. It is oval to elliptical and 
somewhat inflated. The posterior ridge is low and evenly

[[Page 31115]]

rounded when evident. The anterior end is rounded, while the posterior 
margin is bluntly pointed below. Dorsal and ventral margins are curved, 
and the beaks rise slightly above the hinge line. The periostracum 
(membrane on the surface of the shell) is yellowish-tan to reddish-
brown and may have concentric green rings. The beak cavity is shallow, 
and the shell interior is white to dull bluish-white (Parmalee and 
Bogan 1998, p. 185; Williams et al. 2008, p. 533).
    Little is known about the habitat requirements or life history of 
the Georgia pigtoe; however, it is found in shallow runs and riffles 
with strong to moderate current and coarse sand-gravel-cobble bottoms. 
Unionid mussels, such as the Georgia pigtoe, filter-feed on algae, 
detritus, and bacteria from the water column. The larvae of most 
unionid mussels are parasitic, requiring a period of encystment on a 
fish host before they can develop into juvenile mussels. The fish host 
and glochidia (parasitic larvae) of Georgia pigtoe are currently 
unknown.
    The Georgia pigtoe was historically found in large creeks and 
rivers of the Coosa River drainage of Alabama, Georgia, and Tennessee 
(Johnson and Evans 2000, p. 106; Williams et al., 2008, p. 534). There 
are historical reports or museum records of the Georgia pigtoe from 
Tennessee (Conasauga River in Polk and Bradley Counties), Georgia 
(Conasauga River in Murray and Whitfield Counties, Chatooga River in 
Chatooga County; Coosa River in Floyd County, Etowah River in Floyd 
County), and Alabama (Coosa River in Cherokee County, Terrapin Creek in 
Cherokee County, Little Canoe and Shoal Creeks in St. Clair County, 
Morgan Creek in Shelby County, and Hatchet Creek in Coosa County) 
(Florida Museum of Natural History Malacology Database (FLMNH) 2006; 
Gangloff 2003, p. 45). Based on these historical records, the range of 
the Georgia pigtoe included more than 480 km (300 mi) of river and 
stream channels. Additional historical Coosa River tributary records 
credited to Hurd (1974, p. 64) (for example, Big Wills, Little Wills, 
Big Canoe, Oothcalooga, Holly Creeks) have been found to be 
misidentifications of other species (M. Gangloff in litt. 2006).
    In 1990, the Service initiated a status survey and review of the 
molluscan fauna of the Mobile River Basin (Hartfield 1991, p. 1). This 
led to extensive mollusk surveys and collections throughout the Coosa 
River drainage (Bogan and Pierson 1993a, pp. 1-27; P. Hartfield in 
litt. 1990-2001). At all localities surveyed in the Coosa River 
drainage, the freshwater mussel fauna had declined from historical 
levels, and at all but a few localized areas, the fauna proved to be 
completely eliminated or severely reduced due to a variety of impacts, 
including point and non-point source pollution, and channel 
modifications such as impoundment. Following a review of these efforts 
and observations, the Service reported 14 species of mussels in the 
genus Pleurobema, including the Georgia pigtoe, as presumed extinct, 
based on their absence from collection records, technical reports, or 
museum collections for a period of 20 years or more (Hartfield 1994, p. 
1).
    The Service and others continued to conduct surveys in the Coosa 
River drainage for mollusks (P. Hartfield in litt. 1990-2001; Williams 
and Hughes 1998, pp. 2-6; Johnson and Evans 2000, p. 106; Herod et al. 
2001, pp i-ii; Gangloff 2003, pp. 11-12; McGregor and Garner 2004, pp. 
1-18; Johnson et al. 2005, p. 1). Several freshly dead and live 
individuals of the Georgia pigtoe were collected during these mussel 
surveys in the Upper Conasauga River, Murray and Whitfield Counties, 
Georgia (Williams and Hughes 1998, p. 10; Johnson and Evans 2000, p. 
106). Gangloff (2003, pp. 11-12, 45) conducted mussel surveys of Coosa 
River tributaries in Alabama, including all known historical collection 
sites for the Georgia pigtoe, without relocating the species. McGregor 
and Garner (2004, p. 8) surveyed the Coosa River dam tailraces for 
mollusks without encountering the Georgia pigtoe.
    The Georgia pigtoe is currently known from a few isolated shoals in 
the Upper Conasauga River in Murray and Whitfield Counties, Georgia, 
and in Polk County, Tennessee (Johnson and Evans 2000, p. 106; Evans 
2001, pp. 33-34). All recent collection sites occur within a 43-km (27-
mi) reach of the river. Within this reach, the Georgia pigtoe is very 
rare (Johnson and Evans 2000, p. 106), and no population estimates are 
available.
Interrupted Rocksnail
    The interrupted rocksnail (Leptoxis foremani) is a small-to-medium-
sized freshwater snail that historically occurred in the Coosa River 
drainage of Alabama and Georgia. The shell grows to approximately 22 mm 
(1 in) in length and may be plicate (folds in the surface) with obscure 
striations (fine longitudinal ridges), subglobose (not quite 
spherical), thick, dark, brown to olive in color, and occasionally 
spotted. The spire (apex) of the shell is very low, and the aperture 
(opening) is large and subrotund (not quite round).
    The interrupted rocksnail, a member of the aquatic snail family 
Pleuroceridae, was described from the Coosa River, Alabama, by Lea in 
1843. Goodrich (1922, p. 13) placed the species in the ``Anculosa 
(=Leptoxis) picta (Conrad 1834) group,'' which also included the 
Georgia rocksnail (Leptoxis downei (Lea 1868)). L. foremani was 
considered to inhabit the Lower Coosa River, with L. downei inhabiting 
the Upper Coosa drainage (Goodrich 1922, pp. 18-19, 21-23). When a 
rocksnail population was rediscovered surviving in the Oostanaula 
River, Georgia, in 1997, it was initially identified as L. downei 
(Williams and Hughes 1998, p. 9; Johnson and Evans 2000, pp. 45-46); 
however, Burch (1989, p. 155) had previously placed L. downei within L. 
foremani as an ecological variation. Therefore, L. downei is currently 
considered an upstream phenotype of the interrupted rocksnail, and L. 
foremani is recognized as the valid name for the interrupted rocksnail 
(Turgeon et al. 1998, p. 67; Johnson 2004, p. 116).
    Rocksnails live in shoals, riffles, and reefs (bedrock outcrops) of 
small to large rivers. Their habitats are generally subject to moderate 
currents during low flows and strong currents during high flows. These 
snails live attached to bedrocks, boulders, cobbles, and gravel and 
tend to move little, except in response to changes in water level. They 
lay their adhesive eggs within the same habitat (Johnson 2004, p. 116). 
Interrupted rocksnails are currently found in shoal habitats with sand-
boulder substrate, at water depths less than 50 centimeters (cm) (20 
in), and in water currents less than 40 cm/second (sec) (16 in/sec) 
(Johnson 2004, p. 116). We know little of the life history of 
pleurocerid snails; however, they generally feed by ingesting 
periphyton (algae attached to hard surfaces) and biofilm detritus 
scraped off of the substrate by the snail's radula (a horny band with 
minute teeth used to pull food into the mouth) (Morales and Ward 2000, 
p. 1). Interrupted rocksnails have been observed grazing on silt-free 
gravel, cobble, and boulders (Johnson 2004, p. 116). They have survived 
as long as 5 years in captivity (Johnson in litt. 2006b).
    The interrupted rocksnail was historically found in colonies on 
reefs and shoals of the Coosa River and several of its tributaries in 
Alabama and Georgia. The range of the rocksnail formerly encompassed 
more than 800 km (500 mi) of river and stream channels, including the 
Coosa River (Coosa, Calhoun, Cherokee, Elmore, Etowah, Shelby, St. 
Clair, and Talladega

[[Page 31116]]

Counties), Lower Big Canoe Creek (St. Clair County), and Terrapin Creek 
(Cherokee County) in Alabama; and the Coosa and Lower Etowah Rivers 
(Floyd County), the Oostanaula River (Floyd and Gordon Counties), the 
Coosawattee River (Gordon County), and the Conasauga River (Gordon, 
Whitfield, and Murray Counties) in Georgia (Goodrich 1922, pp. 19, 21; 
Johnson 2004, p. 116; FLMNH 2006).
    Snail surveys conducted within the historical range of the 
interrupted rocksnail (Bogan and Pierson 1993a, pp. 1-27; Williams and 
Hughes 1998, pp. 1-21) resulted in the collection of only a single live 
specimen from the Oostanaula River, Floyd County, Georgia, during 1997 
(Williams and Hughes 1998, p. 9). Intensive surveys of the Oostanaula, 
Coosa, Coosawattee, Etowah, and Conasauga Rivers since 1999 have 
located the species in about 12 km (7.5 mi) of the Oostanaula River 
upstream of the Gordon-Floyd County line (Johnson and Evans 2000, pp. 
45-46; Johnson and Evans 2001, pp. 2, 25). A captive colony was 
maintained at the Tennessee Aquarium Research Institute (TNARI) from 
2000 through 2005 for study and propagation. In coordination with TNARI 
and the Service, the Alabama Department of Conservation and Natural 
Resources (ADCNR) developed a plan and strategy to reintroduce 
interrupted rocksnails from the TNARI colony into the Coosa River above 
Wetumpka, Elmore County, Alabama (ADCNR 2003, pp. 1-4). In 2003, 2004, 
and 2005, approximately 3,200, 1,200, and 3,000 juvenile snails, 
respectively, from the TNARI culture were released into the Lower Coosa 
River (ADCNR 2004, p. 33; P. Johnson in litt. 2005a). In 2005, ADCNR 
established the Alabama Aquatic Biodiversity Center (AABC) at the 
Marion State Fish Hatchery for the culture of imperiled mollusk 
species, and the interrupted rocksnail TNARI colony was transferred to 
that facility.
    Following its rediscovery, the interrupted rocksnail population 
size on shoals in the Oostanaula River declined from a high of 10 to 45 
snails per square meter (m\2\) (1.2 square yards (yd\2\) in 1999 
(Johnson and Evans 2001, p. 22) to only 20 snails found during 6 
search-hours in 2004 (P. Johnson in litt. 2003, 2004). The cause of 
decline was suspected to be some form of water contamination (P. 
Johnson in litt. 2003, 2004; P. Hartfield in litt. 2006). A July 2006 
search for adults to use as hatchery stock failed to locate any 
rocksnails in more than 2 search-hours (P. Hartfield in litt. 2006). 
However, a subsequent search in August 2006 under lower flow conditions 
resulted in the location of 89 snails in 4 search-hours at one shoal, 
and 2 rocksnails in 4 search-hours at another shoal (P. Johnson in 
litt. 2007a).
    Since their reintroduction into the Lower Coosa River of Alabama, a 
few of the 2003 hatchery-cultured interrupted rocksnails were observed 
in the vicinity of the release site in 2004 (Johnson in litt. 2005c). 
An alternative site was selected for release in August 2005, and 18 
snails were located 3 months following release (M. Pierson in litt. 
2005). During a 40-minute search of this release area in 2006, two 
interrupted rocksnails were found (P. Johnson in litt. 2007b). 
Observations of only small numbers of reintroduced snails may be due to 
habitat size and dispersal, low fecundity of the species, predation, 
reproductive failure due to dispersal, or habitat disturbance (Johnson 
in litt. 2005b).
Rough Hornsnail
    The rough hornsnail's (Pleurocera foremani) shell is elongated, 
pyramidal, and thick. Growing to about 33 mm (1.3 in) in length, the 
shell has as many as nine yellowish-brown whorls. The aperture is 
elongated, angular, channeled at the base, and usually white inside. 
The presence of prominent nodules or tubercles on the lower whorls 
above the aperture is the most distinctive feature that separates it 
from other hornsnails (Tryon 1873, p. 53). These tubercles, along with 
the size and shape of the shell, distinguish the species from all other 
pleurocerid snails (Elimia spp., Leptoxis spp., Pleurocera spp.) in the 
Mobile River Basin.
    The rough hornsnail is a member of the aquatic snail family of 
Pleuroceridae. The species was described in 1843 by Lea as Melania 
foremanii (=foremani) (Tryon 1873, p. 52). It was later placed in the 
genus Pleurocera by Tryon (1873, p. 52), who noted that P. foremani 
closely resembled species of that genus. Goodrich (1935, p. 3) reported 
a variation of a species of Pleurocera in the Cahaba River that 
resembled foremani, but later identified that variant as a ``mutation'' 
or form of brook hornsnail (P. vestitum) (Goodrich 1941, p. 12). This 
variant, however, is no longer extant in the Cahaba River (Bogan and 
Pierson 1993b, p. 12; Sides 2005, pp. 21-22, 28). Goodrich (1944, p. 
43) considered that the Coosa River P. foremani might also be 
eventually found to be simply a variant of smooth hornsnail (P. 
prasinatum), another more widely distributed species in the Coosa 
River.
    In a recent dissertation on the systematics of the Mobile River 
Basin Pleurocera, the rough hornsnail was found to be both 
morphologically and genetically distinct from other species in the 
genus (Sides 2005, pp. 26, 127). This analysis also found that the 
rough hornsnail was genetically more closely allied to a co-occurring 
species in the genus Elimia, and concluded that it should be recognized 
as Elimia foremani (Sides 2005, pp. 26-27). Although the Sides (2005, 
pp. 26-27) study provides some evidence that this species should be 
placed in the genus Elimia, this taxonomic change has not been formally 
peer-reviewed and published. Therefore, for the purposes of this 
action, we will continue to use currently recognized nomenclature for 
the rough hornsnail (Pleurocera foremani).
    Rough hornsnails are primarily found on gravel, cobble, and bedrock 
in moderate currents. They have been collected at depths of 1 m (3.3 
ft) to 3 m (9.8 ft) (Hartfield 2004, p. 132). The species appears to 
tolerate low-to-moderate levels of silt deposition (Sides 2005, p. 
127). Little is known regarding the life history characteristics of 
this species. Snails in the genus Pleurocera generally lay their eggs 
in a spiral arrangement on smooth surfaces (Sides 2005, pp. 26-27), 
whereas Elimia snails generally lay eggs in short strings (P. Johnson 
2006). Attempts to induce rough hornsnails to lay eggs in captivity 
have been unsuccessful (Sides 2005, p. 27).
    The rough hornsnail is endemic to the Coosa River system in 
Alabama. Goodrich (1944, p. 43) described the historical range as the 
Coosa River downstream of the Etowah River and at the mouths of a few 
tributaries. The Etowah River enters the Coosa River in Floyd County, 
Georgia; however, there are no known museum or site-specific records of 
the rough hornsnail that validate its range into the State of Georgia 
(P. Johnson in litt. 2006a). Historical museum records of the rough 
hornsnail in the Coosa River (FLMNH 2006, and elsewhere) indicate that 
they occurred from Etowah, St. Clair, Shelby, Talladega, and Elmore 
Counties, Alabama, a historical range of approximately 322 river km 
(200 river mi). There are also historical museum records of this 
species from nine Coosa River tributaries in Alabama, including Big 
Wills Creek in Etowah County; Kelly, Big Canoe, and Beaver Creeks in 
St. Clair County; Ohatchee Creek, Calhoun County; Choccolocco and 
Peckerwood Creeks in Talladega County; Yellowleaf Creek, Shelby County; 
and Yellow Leaf Creek in Chilton County (FLMNH 2006).
    The rough hornsnail is currently known to occur at two locations: 
Lower

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Yellowleaf Creek in Shelby County, Alabama; and the Lower Coosa River 
below Wetumpka Shoals in Elmore County, Alabama (Sides 2005, p. 40). 
There are also museum records of the species from Wetumka Shoals in the 
early 1990s (FLMNH 2006); however, the species has not been collected 
from the shoal reach in recent surveys (Johnson 2002, pp. 5-9). 
Yellowleaf Creek is a moderately sized stream where rough hornsnails 
have been collected from about a 50-m (55-yd) length of the stream. At 
this location, rough hornsnails occur at densities of 8 to 32 m\2\ (1.2 
yd\2\) (Pierson in litt. 2006). The Lower Coosa River is a large river 
channel where rough hornsnails have been found in an area of about 100 
m\2\ (120 yd\2\) (P. Hartfield 2001). No quantitative estimates have 
been made at this site. Searches of unimpounded reaches of the Coosa 
River and the lower portions of tributaries to the Coosa have failed to 
locate the species elsewhere (Bogan and Pierson 1993a, pp. 1-27; 
Garner, pers. com. 2005; Hartfield in litt. 2006). The two known 
surviving populations are separated by three impoundments and about 113 
km (70 mi) of impounded channel habitat.

Previous Federal Action

    The interrupted rocksnail and rough hornsnail were first identified 
as candidates for protection under the Act in the November 21, 1991, 
Federal Register (56 FR 58804). They were assigned a category 2 status 
designation, which was given to those species for which there was some 
evidence of vulnerability, but for which additional biological 
information was needed to support a proposed rule to list as endangered 
or threatened. In the November 15, 1994, notice of candidate review (59 
FR 58982), the rough hornsnail was again assigned a category 2 status, 
while the status category for the interrupted rocksnail (Leptoxis 
foremani) was changed to 3A (taxa for which the Service has persuasive 
evidence of extinction).
    Assigning categories to candidate species was discontinued in 1996 
(Notice of Candidate Review; February 28, 1996; 61 FR 7596), and only 
species for which the Service has sufficient information on biological 
vulnerability and threats to support issuance of a proposed rule are 
now regarded as candidate species. Candidate species were also assigned 
listing priority numbers based on immediacy and the magnitude of 
threat, as well as their taxonomic status (48 FR 43098; Sept. 21, 
1983). Due to a need for taxonomic clarification, the rough hornsnail 
was dropped as a candidate species in 1996.
    In 1997, we received reports of a small population of the 
interrupted rocksnail surviving in the Ostanaula River, Georgia, along 
with reports of Georgia pigtoe collections in the Conasauga River of 
Georgia and Tennessee, and their status as candidates was reevaluated. 
In the 1999 (64 FR 57533), 2001 (66 FR 54808), 2002 (67 FR 40657), and 
2004 (69 FR 24876) Federal Register notices of candidate review, both 
the Georgia pigtoe and interrupted rocksnail (as Georgia rocksnail, 
Leptoxis downei) were identified as listing priority 5 candidate 
species. In the May 11, 2005, Federal Register notice of candidate 
review (70 FR 24870) the nomenclature was corrected for the interrupted 
rocksnail, and the listing priority for both species was changed from 5 
to 2, based on the continued rarity of the Georgia pigtoe and a decline 
in abundance of the interrupted rocksnail. The rough hornsnail was 
recognized as a listing priority 2 candidate in the September 12, 2006, 
Federal Register notice of candidate review (71 FR 53756), following 
clarification of its taxonomy, along with the interrupted rocksnail and 
Georgia pigtoe.

Summary of Factors Affecting the Species

    Section 4 of the Act (16 U.S.C. 1533), and implementing regulations 
at 50 CFR part 424, set forth procedures for adding species to the 
Federal Lists of Endangered and Threatened Wildlife and Plants. Under 
section 4(a) of the Act, we may list a species on the basis of any of 
five factors, as follows: (A) The present or threatened destruction, 
modification, or curtailment of its habitat or range; (B) 
overutilization for commercial, recreational, scientific, or 
educational purposes; (C) disease or predation; (D) the inadequacy of 
existing regulatory mechanisms; or (E) other natural or manmade factors 
affecting its continued existence. In making this finding, information 
regarding the status and trends of the Georgia pigtoe, interrupted 
rocksnail, and rough hornsnail are considered in relation to the five 
factors provided in section 4(a)(1) of the Act.
    Under section 3 of the Act, a species is ``endangered'' if it is in 
danger of extinction throughout all or a significant portion of its 
range and is ``threatened'' if it is likely to become endangered within 
the foreseeable future throughout all or a significant portion of its 
range. The word ``range'' refers to the range in which the species 
currently exists. Range is discussed further below in the Conclusion 
section of this proposed rule.
    Foreseeable future is determined by the Service on a case-by-case 
basis, taking into consideration a variety of species-specific factors 
such as lifespan, genetics, breeding behavior, demography, threat 
projection timeframes, and environmental variability.
    The average lifespan of the interrupted rocksnail in the wild is 
unknown; however, interrupted rocksnails have survived in captivity for 
as long as 5 years (Johnson in litt. 2006b). Heavy-shelled mussels are 
known to have long life spans, with many species living from 30 to 70 
years (Williams et al. 2008, p. 68). For the purposes of this analysis, 
we estimate a life span of 30 years for the Georgia pigtoe.
    Some percentage of rocksnails cultured in captivity have been 
observed ovipositing in their first year, but all are believed to 
become sexually mature in their second year. Less is known about the 
rough hornsnail; however, some pleurocerid snails in the genus Elimia 
may live up to 5 years (Dillon 1988, p. 113). It is also believed that 
most pleurocerid snails may begin reproducing within 1 year post-hatch, 
depending upon habitat and productivity (Johnson 2008).
    The age of sexual maturity for the Georgia pigtoe is unknown and 
varies widely among the genera of freshwater mussels. In general, thin-
shelled species reach sexual maturity earlier and have shorter 
lifespans than heavier-shelled species. In the Mobile River Basin, age 
at sexual maturity for mussels has been shown to vary from 1 to 2 years 
for the thin-shelled southern pocketbook (Lampsilis ornata), and 3 to 9 
years for the heavy-shelled Alabama orb (Quadrula asperata) (Haag and 
Staton 2003, pp. 2122-2123). The Georgia pigtoe is similar in shell 
size and thickness to the Alabama orb, so we are estimating sexual 
maturity for the Georgia pigtoe at age 5 years, and a generational time 
span of 5 years. Heavy-shelled mussels are also known to have long life 
spans, with many species living from 30 to 70 years (Williams et al. 
2008, p. 68).
    Threat projection timeframes for the Georgia pigtoe, interrupted 
rocksnail, and rough hornsnail include specific activities that can 
arise at any time (such as permitted discharges, construction 
activities, channel modifications, or random accidents and spills of 
toxic substances) and periodic weather events (such as droughts and 
floods).
    The following analysis examines all five factors currently 
affecting or that are likely to affect Georgia pigtoe,

[[Page 31118]]

interrupted rocksnail, and rough hornsnail snail. The five factors 
listed under section 4(a)(1) of the Act and their application to the 
Georgia pigtoe mussel (Pleurobema hanleyianum (Lea 1852)), interrupted 
rocksnail (Leptoxis foremani (Lea 1843)), and rough hornsnail 
(Pleurocera foremani (Lea 1843)) are as follows:

A. The present or threatened destruction, modification, or curtailment 
of its habitat or range.

    All three species have experienced significant curtailment of their 
occupied habitats (see ``Background'' above). The Georgia pigtoe has 
been eliminated from about 90 percent of its historical range of 480 
river km (298 river mi). It now inhabits only 43 river km (27 river 
mi). Interrupted rocksnail has been eliminated from 99 percent of a 
historical range of 800 river km (497 river mi), and is now known from 
12 river km (7 river mi). The rough hornsnail has disappeared from more 
than 99 percent of a historical range of 321 river km (199 river mi) 
and now occurs in less than 1 river km (0.6 river mi). The primary 
cause of range curtailment for all three species has been modification 
and destruction of river and stream habitats, primarily by the 
construction of large hydropower dams on the Coosa River. This was 
compounded by fragmentation and isolation of the remaining free-flowing 
portions of the Coosa River and its tributaries, as well as their 
increased vulnerability to local historical events of water quality and 
habitat degradation.
Dams and Impoundments
    Dams eliminate or reduce river flow within impounded areas, trap 
silts and cause sediment deposition, alter water temperature and 
dissolved oxygen levels, change downstream water flow and quality, 
affect normal flood patterns, and block upstream and downstream 
movement of species (Watters 1999, pp. 261-264; McAllister et al. 2000, 
p. iii; Marcinek et al. 2005, pp. 20-21). Within impounded waters, 
decline of freshwater mollusks has been attributed to sedimentation, 
decreased dissolved oxygen, and alteration in resident fish populations 
(Neves et al. 1997, pp. 63-64; Watters 1999, pp. 261-264; Marcinek et 
al. 2005, pp. 9-10). Below dams, mollusk declines are associated with 
changes and fluctuation in flow regime, scouring and erosion, reduced 
dissolved oxygen levels and water temperatures, and changes in resident 
fish assemblages (Williams et al. 1992b, p. 7; Neves et al. 1997, pp. 
63-64; Watters 1999, pp. 261-264; Marcinek et al. 2005, pp. 20-21). The 
decline and extinction of freshwater snails and mussels in the Mobile 
River Basin has been directly attributed to construction of numerous 
large impoundments in the major river systems (Williams et al. 1992b, 
pp. 1-8; Bogan et al. 1995, pp. 250-251; Lydeard and Mayden 1995, pp. 
803-804; Neves et al. 1997, pp. 62, 64; Marcinek et al. 2005, p. 9).
    The Georgia pigtoe, interrupted rocksnail, and rough hornsnail are 
all endemic to the Coosa River system. The Coosa River was impounded by 
six major dams constructed between 1928 and 1966. Today, more than 60 
percent of the Coosa River and its 19 largest tributaries are inundated 
or affected by flow regulation (Marcinek et al. 2005, pp. 12-16).
    Dam construction on the Coosa River had a secondary effect of 
fragmenting the ranges of aquatic mollusk species, leaving relict 
habitats and populations isolated by the structures as well as by 
extensive areas of uninhabitable, impounded waters. These isolated 
populations were left more vulnerable to, and affected by, natural 
events (such as droughts), runoff from common land-use practices (such 
as agriculture, mining, urbanization), discharges (such as municipal 
and industrial wastes), and accidents (such as chemical spills) that 
reduced population levels or eliminated habitat (Neves et al. 1997, pp. 
64-71; U.S. Fish and Wildlife Service 2000, pp. 14-15). As a result, 
many relict populations became locally extirpated, and many mollusk 
species were driven to extinction (Bogan et al. 1995, pp. 250-251; 
Lydeard and Mayden 1995, pp. 803-804; Neves et al. 1997, pp. 54, 62; 
U.S. Fish and Wildlife Service 2000, pp. 6-9). If conditions 
subsequently improved, the surviving mollusk species were unable to 
naturally recolonize suitable areas, due to impediments created by the 
dams and impounded waters.
    The only known natural population of the interrupted rocksnail 
occurs in the free-flowing Oostanaula River (Williams and Hughes 1998, 
p. 9; Johnson and Evans 2001, p. 25). The Oostanaula River is formed by 
the confluence of the Conasauga and Coosawatee Rivers. The Upper 
Coosawatee is impounded by Carters Dam, a hydropower dam which 
discharges into Carters Re-regulation Dam and from there into the 
Coosawatee River. Hydropower discharges from Carters Dam are believed 
to be implicated in the disappearance of the interrupted rocksnail from 
the Coosawattee River (Johnson and Evans 2001, p. 26). The effects of 
power generation discharges from Carters Dam, along with cold water 
temperatures are evident downstream (Williams and Hughes 1998, p. 11), 
even to the shoals on the Oostanaula River where the interrupted 
rocksnail is found (Johnson and Evans 2001, p. 26; Marcinek et al. 
2005, p. 15). A Federal Energy Regulatory Commission (FERC) license was 
issued to construct a hydroelectric facility on the Carters Re-
regulation Dam (FERC 2001, pp. 1-2). A notice of probable termination 
of license has been issued due to failure to commence construction in a 
timely manner (FERC 2005a, pp. 1-2). An appeal to the termination order 
was made (FERC 2005b, p. 1) but denied (FERC 2006a, pp. 1-3). However, 
the applicant has since applied for a preliminary permit to proceed 
with the hydroelectric facility (FERC 2006b, pp. 1-3).
    Rough hornsnails currently survive in Lower Yellowleaf Creek, at 
the transitional area between the flowing stream and the embayment 
created by Lay Dam, and in a small area of the Coosa River below the 
shoals along the Fall Line near Wetumpka, Alabama. Known from the main 
channel of the Coosa River and the mouths of some of the larger 
tributaries, all historical habitats, including those two where the 
rough hornsnail currently survives, are affected to some degree by 
impounded waters and hydropower releases.
    The Georgia pigtoe historically occurred in the Coosa River and 
many of its major tributaries. As noted above, the Coosa is impounded 
throughout most of its length by major hydropower dams. In addition, 
all historically occupied tributaries are isolated from each other by 
one or more of these dams and extensive reaches of impounded waters. 
The species is currently known to survive only in the Upper Conasauga 
River, far above the influence of the Coosa River impoundments.
Water and Habitat Quality
    The disappearance of shoal populations of rough hornsnail, 
interrupted rocksnail, and Georgia pigtoe from unimpounded relict 
habitats in the Coosa River drainage is likely due to historical 
pollution problems. Pleurocerid snails and freshwater mussels are 
highly sensitive to water and habitat quality (Havlik and Marking 1987, 
pp 1-15; Neves et al. 1997, pp. 64-69). Historical causes of water and 
habitat degradation in the Coosa River and its tributaries included 
drainage from gold mining activities, industrial and municipal 
pollution events, and construction and agricultural runoff (for 
example, Hurd 1974, pp. 38-40; Lydeard and Mayden 1995, pp. 803-804; 
Freeman et al. 2005, pp. 560-562).

[[Page 31119]]

    Prior to the passage of the Federal Clean Water Act (33 U.S.C. 1251 
et seq., 1972) and the adoption of State water quality regulations and 
criteria, water pollution was a significant factor in the disappearance 
of mollusks from unimpounded river and stream channels in the Mobile 
River Basin (Baldwin 1973, p. 23; Hurd 1974, pp. 38-40, 144-151). Hurd 
(1974, pp. 147-149), for example, noted the extirpation of freshwater 
mussel communities from the Conasauga River below Dalton, Georgia, 
apparently as a result of textile and carpet mill waste discharges. He 
also attributed the disappearance of the mussel fauna from the Etowah 
River and other tributaries of the Coosa River to organic pollution and 
siltation. Baldwin (1973, p. 23) documented the loss of mussel 
diversity in the Cahaba River and identified the primary causes as 
pollution from coalfields and industrial and urban wastes.
    Although Federal and State water quality laws and regulations have 
generally reduced the impacts of point source discharges, nonpoint 
source pollution continues to affect and possibly threaten the 
remaining populations of each of these mollusk species. Nonpoint source 
pollution has been identified as a concern in the Yellowleaf Creek and 
Lower Coosa River watersheds (Alabama Clean Water Partnership (ACWP) 
2005 Chapter 12). These drainages encompass historical habitat for the 
interrupted rocksnail and Georgia pigtoe, currently occupied habitat 
for the rough hornsnail, and a recent reintroduction of the interrupted 
rocksnail. Both Yellowleaf Creek and the eastern watershed of the Lower 
Coosa River have been designated as High Priority Watersheds by the 
ACWP (2005 Chap. 12), due to the high potential of nonpoint source 
pollution associated with expanding human population growth rates and 
urbanization. The headwaters of Yellowleaf Creek are about 5 km (3 mi) 
southeast of the greater metropolitan area surrounding Birmingham, and 
the watershed is highly dissected by county roads. The Lower Coosa 
River is about 16 km (10 mi) north of the Montgomery greater 
metropolitan area and is accessible by a four-lane highway. Both 
general areas are experiencing growth due to their proximity to major 
metropolitan areas.
    Nonpoint source pollution and habitat deterioration are also 
problems in the Upper Coosa River Basin, including the Conasauga and 
Oostanaula rivers (Georgia Department of Natural Resources (GDNR) 1998, 
pp. 4.27-4.42). In the reaches of the Conasauga River where the Georgia 
pigtoe continues to survive, overall molluscan abundance and diversity 
have experienced a general decline over the past two decades that has 
been primarily attributed to water or sediment toxicity and channel 
instability (Johnson and Evans 2000, pp. 171-173; Sharpe and Nichols 
2005, pp. 81-88). Sedimentation has been identified as a potential 
limiting factor for the interrupted rocksnails in the Oostanaula River 
(Johnson and Evans 2001, p. 26). Following its rediscovery, the 
interrupted rocksnail population size in the Oostanaula River has 
declined from a high of 10 to 45 snails per square meter (10.7 sq ft) 
in 1999 (Johnson and Evans 2001, p. 22) to only 20 snails found during 
6 search-hours in 2004 (P. Johnson in litt. 2003, 2004). The cause of 
decline is suspected to be some form of water contamination (P. Johnson 
in litt. 2003, 2004; P. Hartfield in litt. 2006).
    Nonpoint source pollution from land surface runoff originates from 
virtually all land use activities and includes sediments; fertilizer, 
herbicide, and pesticide residues; animal or human wastes; septic tank 
leakage and gray water discharge; and oils and greases (GDNR 1998, pp. 
4.27-4.42; ACWP 2005, Chap. 9). Nonpoint source pollution can cause 
excess sedimentation, nutrification, decreased dissolved oxygen 
concentration, increased acidity and conductivity, and other changes in 
water chemistry that can seriously impact aquatic mollusks. Land use 
types around the Georgia pigtoe, interrupted rocksnail, and rough 
hornsnail populations include pastures, row crops, timber, and urban 
and rural communities.
    Excessive sediments are believed to impact riverine mollusks 
requiring clean, stable streams (Ellis 1936, pp. 39-40; Brim Box and 
Mossa 1999, p. 99). Impacts resulting from sediments have been noted 
for many components of aquatic communities. For example, sediments have 
been shown to abrade or suffocate periphyton (organisms attached to 
underwater surfaces, upon which snails may feed); affect respiration, 
growth, reproductive success, and behavior of aquatic insects and 
mussels; and affect fish growth, survival, and reproduction (Waters 
1995, pp. 173-175). Potential sediment sources within a watershed 
include virtually all activities that disturb the land surface, and all 
localities currently occupied by these mollusks are affected to varying 
degrees by sedimentation.
    Land surface runoff also contributes nutrients to rivers and 
streams. Excessive nutrient input (for example, nitrogen and phosphorus 
from fertilizers, sewage, and animal manure) can result in effects that 
are detrimental to aquatic species. High levels of nutrients in surface 
runoff can promote excessive filamentous algal growth. Dense algal 
growth covers gravel, cobble, or bedrock substrates and interstices 
(spaces between bottom particles), and can seriously reduce dissolved 
oxygen in waters during dark hours due to algal respiration (Shepard et 
al. 1994, pp. 61-64), which affects feeding, reproduction, and 
respiration in adult and juvenile mussels and snails, and limits access 
to substrate interstices important to juvenile and adult mussels. Algal 
mats also provide cover for invertebrate predators of juvenile mollusks 
(such as flatworms, hydra, and chironomids) and increase their 
vulnerability to such predators. Filamentous algae may also displace 
certain species of fish, or otherwise affect fish-mussel interactions 
essential to recruitment (for example, Hartfield and Hartfield 1996, p. 
373). In hatcheries, filamentous algal growth reduces juvenile mussel 
survival by reducing flow, increasing sedimentation, and causing 
competition with and reduction of the unicellular algal community on 
which the mussels feed (R. Neves 2002). Nutrient and sediment pollution 
may have synergistic effects (when the toxic effect of two or more 
pollutants operating together is greater than the sum of the effects of 
the pollutants operating individually) on freshwater mollusks, as has 
been suggested for aquatic insects (Waters 1995, p. 67).
    Land surface runoff contributes the majority of human-induced 
sediments and nutrients to water bodies throughout the United States. 
The human population is expanding within the areas currently occupied 
by the Georgia pigtoe, interrupted rocksnail, and rough hornsnail, 
increasing the sediment and nutrient input to their riverine habitats, 
and leaving these mollusks vulnerable to progressive water and habitat 
degradation from land surface runoff.
    Accidental spills that may affect water or habitat quality also 
threaten surviving populations of each species. For example, on 
September 12, 2006, a train derailment spilled four tank cars of 
soybeans into a tributary of Yellowleaf Creek (Birmingham News in litt. 
2006). A large rain event flushed the decomposing soybeans into 
Yellowleaf Creek, resulting in a serious decline in dissolved oxygen in 
the stream, killing fishes, mussels (including two endangered species, 
southern pigtoe and triangular kidneyshell), and snails (including the 
endangered cylindrical

[[Page 31120]]

lioplax) (Johnson 2006). Fortunately, the location of the largest 
surviving population of rough hornsnail is in the lowest reaches of 
Yellowleaf Creek, remote from the spill, and no mortality was observed 
in this population as a result of the spill (Johnson 2006).
    In summary, the historical loss of habitat and range is currently, 
and projected to continue to be, a significant threat to the rough 
hornsnail, interrupted rocksnail, and Georgia pigtoe. Curtailment of 
habitat and range also amplifies threats from nonpoint source water and 
habitat quality degradation, accidental spills, or violation of 
permitted discharges. Due to the extremely limited extent of habitat 
currently occupied by each species, and the severity and magnitude of 
this threat, we have determined that the present or threatened 
destruction, modification, or curtailment of habitat and range 
represents an ongoing and significant threat to the rough hornsnail, 
interrupted rocksnail, and Georgia pigtoe.

B. Overutilization for commercial, recreational, scientific, or 
educational purposes.

    The Georgia pigtoe, interrupted rocksnail, and rough hornsnail are 
not commercially utilized. Each species has been taken for scientific 
and private collections in the past, yet collecting is not considered a 
factor in the decline of these species. While collection is not 
considered a current threat, the desirability of these species in 
scientific and commercial collections may increase as their existence 
and rarity becomes known, and their localized distributions and small 
population sizes leaves them vulnerable to overzealous recreational or 
scientific collecting.

C. Disease or predation.

    Diseases of freshwater mollusks are poorly known and are not 
currently considered to be a threat to the Georgia pigtoe, interrupted 
rocksnail, and rough hornsnail, or a factor in their decline. Aquatic 
snails and mussels are consumed by various vertebrate predators, 
including fishes, mammals, and possibly birds. Although predation by 
naturally occurring predators is a normal aspect of the population 
dynamics of a species and is not known to be a threat to any of these 
species, changes in water flows, depths, temperatures, and other 
environmental factors within some portions of their ranges may have led 
to increased numbers of native mollusk-eating fish, such as freshwater 
drum (Johnson in litt. 2005b). In addition, the potential now exists 
for the black carp (Mylopharyngodon piceus), a mollusk-eating Asian 
fish recently introduced into the waters of the United States (U.S. 
Fish and Wildlife Service 2002), to eventually enter and disperse 
through the Mobile River Basin via the Tennessee-Tombigbee Waterway, or 
by their accidental release from catfish farms or other aquaculture 
facilities.
    In summary, disease in freshwater mollusks is poorly known and not 
currently considered a threat. Although there is no direct evidence at 
this time that predation is detrimentally affecting the Georgia pigtoe, 
interrupted rocksnail, or rough hornsnail, their small populations and 
limited ranges leaves them vulnerable to threats of predation from 
natural or introduced predators. Therefore, we have concluded that 
predation currently represents a threat of low magnitude, but it could 
potentially become a significant future threat to the Georgia pigtoe, 
interrupted rocksnail, or rough hornsnail due to their small population 
sizes.

D. The inadequacy of existing regulatory mechanisms.

    The Alabama Department of Conservation and Natural Resources 
currently recognizes the rough hornsnail as a ``Priority 1'' species 
(Highest Conservation Concern) (Mirarchi et al. 2004, p. 117; ADCNR 
2005, p. 302). The interrupted rocksnail is considered ``Extirpated (in 
Alabama) - Conservation Action Underway'' (Mirarchi et al. 2004, p. 
114), and the Georgia pigtoe is listed as ``extinct'' (Mirarchi et al. 
2004, p. 13). While these classifications identify the status of 
imperiled species in the State of Alabama, they convey no legal 
protection. Interrupted rocksnail and Georgia pigtoe currently lack any 
official status recognition by the State of Georgia, but they have been 
nominated for inclusion on the State Protected Species List. The 
Georgia pigtoe is identified as a species of the Greatest Conservation 
Need by the State of Tennessee. NatureServe (2006) identifies the 
Georgia pigtoe, interrupted rocksnail, and rough hornsnail as G1 
critically imperiled species; however, no State or Federal protection 
is conveyed by these classifications. Without State or Federal 
protection, these three species are not currently given any specific 
special consideration under environmental laws when project impacts are 
reviewed, other than those provided for water quality.
    The mollusk fauna (including the Georgia pigtoe) of the Conasauga 
River and the interrupted rocksnail in the Oostanaula River have 
experienced significant declines in recent years, apparently due to 
water quality or sediment toxicity (Evans 2001, p. 3; Johnson in litt. 
2004; Sharpe and Nichols 2005, pp. 1-4; Konwick et al. 2008, pp. 2016-
2017). There is no specific scientific information on the sensitivity 
of the Georgia pigtoe, interrupted rocksnail, and rough hornsnail or 
their host fish species to common industrial and municipal pollutants, 
and little information on other freshwater mollusks. Current State and 
Federal regulations regarding pollutants are assumed to be protective 
of freshwater mollusks; however, these species may be more susceptible 
to some pollutants than test organisms commonly used in bioassays. For 
example, several recent studies have suggested that U.S. Environmental 
Protection Agency's (EPA) criteria for ammonia may not be protective of 
freshwater mussels (Augspurger et al. 2003, p. 2571; Augspurger et al. 
2007, p. 2026; Newton et al. 2003, pp. 2559-2560; Newton and Bartsch 
2007, p 2057; Ward et al. 2007, p. 2075).
    In a review of the effects of eutrophication on mussels, Patzner 
and Muller (2001, p. 329) noted that stenoecious (narrowly tolerant) 
species disappear as waters become more eutrophic. They also refer to 
studies that associate increased levels of nitrate with the decline and 
absence of juvenile mussels (Patzner and Muller 2001, pp. 330-333). 
Other studies have also suggested that early life stages of mussels are 
more sensitive to metals and such inorganic chemicals as chlorine and 
ammonia than are common bioassay test organisms (Keller and Zam 1991, 
pp. 543-545; Goudreau et al. 1993, p. 221; Naimo 1995, pp. 354-355). 
Therefore, it appears that inadequate research and data prevent 
existing regulations, such as the Clean Water Act (administered by the 
EPA and the U.S. Army Corps of Engineers), from being fully utilized or 
effective in the management and protection of these species.
    Rough hornsnails currently survive at localized sites in Yellowleaf 
Creek and in the Lower Coosa River below Wetumpka Shoals in Alabama. In 
addition, the interrupted rocksnail was recently reintroduced into 
Wetumpka Shoals. The Alabama Department of Environmental Management 
(ADEM) has designated the water use classification for some portions of 
Yellowleaf Creek as ``Swimming'' (S) and others as ``Fish and 
Wildlife'' (F&W). The F&W designation establishes minimum water quality 
standards that are believed to protect

[[Page 31121]]

existing species and water uses (for example, fishing, recreation, 
irrigation) within the designated area, while the S classification 
establishes higher water quality standards that are protective of human 
contact with the water. The Lower Coosa River below Wetumpka is 
currently designated as F&W by ADEM, and adjacent tributaries are 
classified as S. Both water bodies are currently believed to support 
their designated uses. However, Yellowleaf Creek and the eastern 
watershed of the Lower Coosa have been designated as High Priority 
Watersheds by the ACWP (2005, Chap. 12) due to a lack of monitoring 
data and the high potential of nonpoint source pollution in these 
drainages associated with expanding human population growth rates and 
urbanization.
    The reach of the Conasauga River at and below the Tennessee-Georgia 
State Line supports the only known surviving population of the Georgia 
pigtoe. This river reach is identified on Georgia's 303(d) list as 
partially supporting its designated use of Fishing-Drinking Water (GDNR 
2006, p. 35). The Georgia 303(d) list identifies high levels of fecal 
coliform bacteria and Fish Consumption Guidance (FCG) due to 
polychlorinated biphenyls (PCBs) as the reasons for this river reach's 
inclusion on the list, and nonpoint pollution is identified as the 
source of pollutants (GDNR 2006, p. 35). Recent studies have also 
implicated sediment and water toxicity in the decline of mollusks in 
the Conasauga River (Sharpe and Nichols 2005, pp. 81-88; Konwick et al. 
2008, pp. 2016-2017).
    States maintain water-use classifications through issuance of 
National Pollutant Discharge Elimination System (NPDES) permits to 
industries, municipalities, and others that set maximum limits on 
certain pollutants or pollutant parameters. For water bodies on the 
303(d) list, States are required under the Clean Water Act to establish 
a total maximum daily load (TMDL) for the pollutants of concern that 
will bring water quality into the applicable standard. The Georgia 
Department of Natural Resources has identified TMDLs for the Oostanaula 
River to address existing problems of PCBs and fecal coliform loads 
from nonpoint source and urban runoff sources.
    In summary, recent declines in mollusk communities within the 
ranges of each of these species has been attributed to poor water or 
sediment quality. Although regulatory mechanisms are in place to 
protect aquatic species, a lack of specific information on the 
sensitivity of the Georgia pigtoe, interrupted rocksnail, and rough 
hornsnail and their host fish to common industrial and municipal 
pollutants limits their application. Water and sediment quality is 
believed to currently affect (and is expected to continue to affect) 
the Georgia pigtoe and interrupted rocksnail and has been identified as 
a concern for the rough hornsnail in Yellowleaf Creek. Therefore, we 
have determined that the threat of inadequate existing regulatory 
mechanisms is an imminent threat of high magnitude to the Georgia 
pigtoe, interrupted rocksnail, and rough hornsnail.

E. Other natural or manmade factors affecting its continued existence.

    As noted under Factor A, above, the Georgia pigtoe, interrupted 
rocksnail, and rough hornsnail have been eliminated from 90 percent or 
more of their historical ranges. Surviving populations of each species 
are small, extremely localized, isolated, and vulnerable to habitat 
modification, toxic spills, and progressive degradation from land 
surface runoff (non-point source runoff) (see Factor A: Dams and 
Impoundments, Water and Habitat Quality; and Factor D: The inadequacy 
of existing regulatory mechanisms). These conditions also leave each 
species vulnerable to catastrophic changes to their habitats that may 
result from natural events such as flood scour and drought.
    There is a growing concern that climate change may lead to 
increased frequency of severe storms and droughts (for example, 
Golladay et al. 2004, p. 504; McLaughlin et al. 2002, p. 6074; Cook et 
al. 2004, p. 1015). During 2007-2008, a severe drought affected the 
Coosa River watershed in Alabama and Georgia. Streamflow for the 
Conasauga River at Tilton, Georgia, during September 2007, was the 
lowest recorded for any month in 69 years (U.S. Geological Survey 
2007). Although the effects of the drought on the Georgia pigtoe, 
interrupted rocksnail, and rough hornsnail have not been quantified, 
mollusk declines as a direct result of drought have been documented 
(for example, Golladay et al. 2004, p. 494; Haag and Warren 2008, p. 
1165). Reduction in local water supplies due to drought is also 
compounded by increased human demand and competition for surface and 
ground water resources for power production, irrigation, and 
consumption (Golladay et al. 2004, p. 504).
    Freshwater mussels and snails are capable of moving only short 
distances. As noted previously (see discussion under Factor A: Dams and 
Impoundments), there are numerous obstacles in the Coosa River drainage 
to long distance movement of snails, mussels, or the fish hosts of 
mussels, between relict patches of historically occupied and 
potentially suitable riverine habitats. Therefore, even if habitat 
conditions improve for the survival of the Georgia pigtoe, interrupted 
rocksnail, and rough hornsnail in historically occupied stream and 
river habitats, they will be unable to recolonize those areas without 
human assistance. Low numbers of individuals within these isolated 
populations also increases the risks and consequences of inbreeding and 
reduced genetic diversity (Lynch 1996, pp. 493-494).
    The Georgia pigtoe may be adversely affected by the loss or 
reduction in numbers of the fish host(s) essential to its parasitic 
glochidial stages. The specific fish host(s) for the glochidia of the 
Georgia pigtoe is unknown; therefore, specific impacts on this aspect 
of the mussels' life cycle cannot be evaluated. However, other species 
of mussels in the genus Pleurobema are known to parasitize various 
species of chubs, minnows, stonerollers, and other stream fish species.
    In summary, a variety of natural or manmade factors, such as 
droughts, storms, and toxic spills, threaten surviving populations of 
the Georgia pigtoe, interrupted rocksnail, and rough hornsnail due to 
the highly restricted and fragmented nature of their habitats and their 
small population sizes. Other factors, such as inbreeding, reduced 
genetic diversity, and loss or reduction of fish hosts for the Georgia 
pigtoe, may threaten each of the three species; however, the severity 
and magnitude of these threats are not currently known. Therefore, we 
have determined that other natural and manmade factors, such as 
accidental spills, floods, and droughts, currently pose an imminent and 
high degree of threat to the Georgia pigtoe, interrupted rocksnail, and 
rough hornsnail, and the levels of these threats are projected to 
continue or increase in the future.

Proposed Determination

    We have carefully assessed the best scientific and commercial 
information available regarding the past, present, and future threats 
to the Georgia pigtoe, interrupted rocksnail, and rough hornsnail. 
Section 3(6) of the Act defines an endangered species as ``any species 
which is in danger of extinction throughout all or a significant 
portion of its range.'' Based on the severity and magnitude of the 
threats currently affecting each of these species, we

[[Page 31122]]

propose to list them as endangered species under the Act.
    The most significant historical factor affecting the current status 
of the interrupted rocksnail, rough hornsnail, and Georgia pigtoe was 
the extreme curtailment of their habitat and range, as discussed in 
Factor A (above). Curtailment of habitat and range, along with small 
population sizes, amplifies existing or impending threats from nonpoint 
source water and habitat quality degradation, accidental spills, 
violation of permitted discharges, inadequate knowledge to implement 
existing regulatory measures, floods, or droughts (described under 
Factors A, D, and E). These threats are imminent and high in magnitude 
(applicable to the entire range) for each species. As described in 
Factor C and E above, small populations are also at increased threat 
due to predation from natural or introduced predators, genetic 
isolation, and inbreeding depression; however, these threats are not 
currently known to be imminent.
    Only single, localized populations are known to exist of the 
interrupted rocksnail and Georgia pigtoe, and only two extremely 
localized populations of the rough hornsnail are known. Each species is 
faced with a tenuous future even with only the random variation of 
natural environmental factors. However, the additional threats of water 
and habitat quality degradation or destruction further threaten each 
species and this trend is expected to continue or increase.
    We believe that, when combining the effects of historical, current, 
and projected habitat loss and degradation, historical and ongoing 
drought, and the exacerbating effects of small population sizes and 
isolation, the interrupted rocksnail, rough hornsnail, and Georgia 
pigtoe are in danger of extinction throughout all of their ranges, as 
defined in the ``Summary of Factors Affecting the Species'' above. We 
believe these threats, particularly the threats resulting from habitat 
loss and fragmentation, small population sizes, and random natural or 
human induced events, are current and are projected to continue. We 
have determined that these threats are operating on each species and 
their respective habitats with a high degree of imminence, magnitude, 
and severity (rangewide), as discussed above.
    Based on the best available scientific and commercial information, 
we propose to list the Georgia pigtoe, interrupted rocksnail, and rough 
hornsnail as endangered species under the Act. Without the protection 
of the Act, these species are in danger of extinction throughout all of 
their ranges. This could occur within a few years, given recurring 
drought conditions, accidents, or other existing threats. Furthermore, 
because of their curtailed ranges, and immediate and ongoing 
significant threats to each species throughout their entire respective 
ranges, as described above in the five-factor analysis, we find that it 
is unnecessary to analyze whether there are any significant portions of 
ranges for each species that may warrant a different determination of 
status.
Critical Habitat
    Critical habitat is defined in section 3 of the Act as:
    (1) 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
    (a) essential to the conservation of the species and
    (b) which may require special management considerations or 
protection; and
    (2) 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 
measures provided under the Act are no longer necessary.
    Critical habitat receives protection under section 7 of the Act 
through the prohibition against Federal agencies carrying out, funding, 
or authorizing the destruction or adverse modification of critical 
habitat. Section 7(a)(2) 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 private landowners. Where a 
landowner requests Federal agency funding or authorization for an 
action that may affect a listed species or critical habitat, the 
consultation requirements of Section 7(a)(2) may apply. However, even 
in the event of a destruction or adverse modification finding, the 
Federal action agency's and the applicant's obligation is not to 
restore or recover the species, but to implement reasonable and prudent 
alternatives to avoid destruction or adverse modification of critical 
habitat.
    To be included in a critical habitat designation, the habitat 
within the area occupied by the species must first have features that 
are essential to the conservation of the species. The Service must 
identify, to the extent known using the best scientific data available, 
habitat areas that provide essential life cycle needs of the species 
(areas on which are found the Primary Constituent Elements (PCEs), as 
defined at 50 CFR 424.12(b)). To be included in the designation, the 
features at issue must also be ones that 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. 
Furthermore, our Policy on Information Standards Under the Endangered 
Species Act (published in the Federal Register on July 1, 1994 (59 FR 
34271)), the Information Quality Act (section 515 of the Treasury and 
General Government Appropriations Act for Fiscal Year 2001 (Pub. L. 
106-554; H.R. 5658)), and our associated Information Quality Guidelines 
provide criteria, establish procedures, and provide guidance to ensure 
that our decisions represent the best scientific data available. They 
require our biologists, to the extent consistent with the Act and with 
the use of the best scientific data available, to use primary and 
original sources of information as the basis for recommendations to 
designate critical habitat.
    When we are determining which areas we should as critical habitat, 
our primary source of information is generally the information 
developed during the listing process for the species. Additional 
information sources may include the recovery plan for the species, 
articles in peer-reviewed journals, conservation plans developed by 
States and counties, scientific status surveys and studies, biological 
assessments, or other unpublished materials and expert opinion or 
personal knowledge.
    Habitat is often dynamic, and species may move from one area to 
another over time. Furthermore, we recognize that 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

[[Page 31123]]

Service, are necessary for the recovery of the species. For these 
reasons, a critical habitat designations does not signal that habitat 
outside the designated area is unimportant or may not be required for 
recovery of the species.
    Areas that support populations, but are outside the critical 
habitat designation, will continue to be subject to conservation 
actions we implement under section 7(a)(1) of the Act. They are also 
subject to the regulatory protections afforded by the section 7(a)(2) 
jeopardy standard, as determined on the basis of the best available 
scientific information at the time of the agency action. Federally 
funded or permitted projects affecting listed species outside their 
designated critical habitat areas may still result in jeopardy findings 
in some cases. Similarly, critical habitat designations made on the 
basis of the best available information at the time of designation will 
not control the direction and substance of future recovery plans, 
habitat conservation plans (HCPs), or other species conservation 
planning efforts if new information available to these planning efforts 
calls for a different outcome.
Prudency Determination
    Section 4 of the Act, as amended, and implementing regulations (50 
CFR 424.12) require that, to the maximum extent prudent and 
determinable, we designate critical habitat at the time the species is 
determined to be endangered or threatened. Our regulations at 50 CFR 
424.12(a)(1) state that the designation of critical habitat is not 
prudent when one or both of the following situations exist: (1) The 
species is threatened by taking or other activity and the 
identification of critical habitat can be expected to increase the 
degree of threat to the species; or (2) the designation of critical 
habitat would not be beneficial to the species. There is currently no 
imminent threat of take attributed to collection or vandalism under 
Factor B for each of these species, and identification of critical 
habitat is not expected to initiate such a threat to each of the 
species. Critical habitat designation identifies the physical and 
biological features of the habitat essential to the conservation of the 
interrupted rocksnail, rough hornsnail, and Georgia pigtoe, which may 
require special management and protection. As such, these designations 
will provide information to individuals, local and State governments, 
and other entities engaged in activities or long-range planning in 
areas essential to the conservation of the species. Conservation of the 
interrupted rocksnail, rough hornsnail, and Georgia pigtoe and 
essential features of their habitats will require habitat management, 
protection and restoration, which will be facilitated by knowledge of 
habitat locations and the physical and biological features of those 
habitats. Based on this information, we believe critical habitat would 
be beneficial to each of the species. Therefore, we have determined 
that the designation of critical habitat for the interrupted rocksnail, 
rough hornsnail, and Georgia pigtoe is prudent.
    We have reviewed the available information pertaining to historical 
distribution of the Georgia pigtoe, interrupted rocksnail, and rough 
hornsnail, and the habitat characteristics where they currently 
survive. This and other information represent the best scientific and 
commercial data available and lead us to conclude that we have 
sufficient information necessary to identify specific areas that meet 
the definition of critical habitat. Therefore, we have determined that 
the designation of critical habitat is both prudent and determinable 
for the Georgia pigtoe, interrupted rocksnail, and rough hornsnail.
Methods
    As required by section 4(b)(2) of the Act, we use the best 
scientific data available in determining occupied areas that contain 
the features that are essential to the conservation of the Georgia 
pigtoe, interrupted rocksnail, and rough hornsnail, and unoccupied 
areas that are essential to the conservation of the Georgia pigtoe, 
interrupted rocksnail, and rough hornsnail.
    We have reviewed the available information pertaining to historical 
and current distributions, life histories, and habitat requirements of 
these species. Our sources included: peer reviewed scientific 
publications; unpublished survey reports; unpublished field 
observations by the Service, State, and other experienced biologists; 
and notes and communications from qualified biologists or experts.
Primary Constituent Elements (PCEs)
    In accordance with sections 3(5)(A)(i) of the Act and regulations 
at 50 CFR 424.12, in determining which areas within the geographical 
area occupied at the time of listing to propose as critical habitat, we 
identify the specific PCEs required for the Georgia pigtoe, interrupted 
rocksnail, and rough hornsnail based on their biological needs. We 
consider the physical and biological features that are essential to the 
conservation of each species to be the PCEs laid out in the appropriate 
quantity and spatial arrangement for the conservation of the Georgia 
pigtoe, interrupted rocksnail, and rough hornsnail. 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, and rearing (or development) 
of offspring; and
    (5) Habitats that are protected from disturbance or are 
representative of the historical, geographical, and ecological 
distribution of a species.
    The PCEs required for the Georgia pigtoe, interrupted rocksnail, 
and rough hornsnail are derived from biological needs of the species as 
described in the Background section of this proposal. Unfortunately, 
little is known of the specific habitat requirements of any of these 
mollusk species other than all three require flowing water, stable 
stream or river channels, and adequate water quality. Georgia pigtoe 
mussel larvae also require a currently unknown fish host for 
development to juvenile mussels. To identify the physical and 
biological needs of the species, we have relied on current conditions 
at locations where each of the species survive, the limited information 
available on these three species and their close relatives, and factors 
associated with the decline and extirpation of these and other aquatic 
mollusks from extensive portions of the Mobile River Basin.
Space for Individual and Population Growth and for Normal Behavior
    The Georgia pigtoe, interrupted rocksnail, and rough hornsnail were 
all historically associated with stream and river shoals of the Coosa 
River drainage (Goodrich 1922, p. 5; Johnson and Evans 2001, p. 21; 
Williams et al. 2008). The decline of the aquatic mollusk fauna of the 
Mobile River Basin is directly associated with the loss of shoal 
habitats, primarily due to inundation by impounded waters (Bogan et al. 
1995, pp. 250-251; Lydeard and Mayden 1995, pp. 803-804; Neves et al. 
1997, pp. 63-64; Marcinek et al. 2005, pp. 7-10, 20-21). Shoals are 
defined as discrete areas that are of lower depth, greater slope, 
higher velocity flows, and coarser bed materials relative to other 
channel segments. Shoals include areas that are also referred to as 
riffles, gravel bars, and reefs. Shoals generally have substrates 
composed of bedrock, cobble, boulder, and gravel interspersed with

[[Page 31124]]

sands, and sufficient current velocities to remove finer sediments and 
maintain interstitial habitats (Marcinek et al. 2005, p. 4). The 
interrupted rocksnail and rough hornsnail are found clinging to gravel, 
cobble, and boulders in moderate to strong currents in shoals, while 
Georgia pigtoe mussels are found imbedded in sand-gravel substrates 
within shoals. Rough hornsnails are also found in pools below shoals. 
Shoals and associated pools not only provide space for these three 
mollusks, but also provide cover and shelter and sites for breeding, 
reproduction, and growth of offspring.
    Shoal-pool habitats are formed and maintained by water quantity, 
channel slope, and sediment input to the system. Changes in one or more 
of these parameters can result in channel degradation or channel 
aggradation, with serious effects to mollusks. Therefore, we believe 
that stream channel stability is essential to the conservation of the 
Georgia pigtoe, interrupted rocksnail, and rough hornsnail.
Food
    The interrupted rocksnail and rough hornsnail generally feed by 
ingesting periphyton and biofilm detritus scraped off the substrate by 
the snail's radula (Morales and Ward 2000, p. 1). Unionid mussels, such 
as the Georgia pigtoe, filter algae, detritus, and bacteria from the 
water column (Williams et al. 2008, p. 67). Food availability and 
quality for the Georgia pigtoe, interrupted rocksnail, and rough 
hornsnail in shoal habitats is affected by habitat stability, flow, and 
water quality.
Water
    The Georgia pigtoe, interrupted rocksnail, and rough hornsnail are 
riverine-adapted species that depend upon adequate water flow (Williams 
et al. 2008, p. 534; Goodrich 1922, p. 5) and are not found in ponds or 
lakes. Continuously flowing water is a habitat feature associated with 
all surviving populations of the three species. Flowing water maintains 
the stream bottom and shoal habitats where these species are found, 
transports food items to the sedentary juvenile and adult life stages 
of the Georgia pigtoe, supports the periphyton and biofilm ingested by 
the interrupted rocksnail and rough hornsnail, removes wastes, and 
provides oxygen for respiration for each of the three species.
    The ranges of standard physical and chemical water quality 
parameters (such as temperature, dissolved oxygen, pH, conductivity) 
that define suitable habitat conditions for the Georgia pigtoe, 
interrupted rocksnail, and rough hornsnail have not been investigated. 
However, as relatively sedentary animals, aquatic snails and mussels 
must tolerate the full range of such parameters that occur naturally 
within the streams where they persist. Both the amount (flow) and the 
physical and chemical conditions (water quality) where each of the 
three species currently exist vary widely according to season, 
precipitation events, and seasonal human activities within the 
watershed. Conditions across their historical ranges vary even more due 
to watershed size, geology, geography, and differences in human 
population densities and land uses. In general, each of the species 
survives in areas where the magnitude, frequency, duration, and 
seasonality of water flow are adequate to maintain stable shoal 
habitats (for example, sufficient flow to remove fine particles and 
sediments without causing degradation), and where water quality is 
adequate for year-round survival (for example, moderate to high levels 
of dissolved oxygen, low to moderate input of nutrients, and relatively 
unpolluted water and sediments). Therefore, adequate water flow and 
water quality (as defined below) are essential to the conservation of 
the Georgia pigtoe, interrupted rocksnail, and rough hornsnail. We 
currently believe that most numeric standards for pollutants and water 
quality parameters (for example, dissolved oxygen, pH, heavy metals) 
that have been adopted by the States under the Clean Water Act 
represent levels that are essential to the conservation of each of 
these three mollusks. However, some States' standards may not 
adequately protect mollusks, or are not being appropriately measured, 
monitored, or achieved in some reaches (see Factor A: The present or 
threatened destruction, modification, or curtailment of its habitat or 
range, Water and Habitat Quality; and Factor D: Inadequacy of existing 
regulatory mechanisms, above). The Service is currently in consultation 
with the EPA to evaluate the protectiveness of criteria approved in 
EPA's water quality standards for threatened and endangered species and 
their critical habitats as described in the Memorandum of Agreement 
that our agencies signed in 2001 (66 FR 11201). Other factors that can 
potentially alter water quality are droughts and periods of low flow, 
non-point source runoff from adjacent land surfaces (for example, 
excessive amounts of nutrients, pesticides, and sediment), and random 
spills or unregulated discharge events. This could be particularly 
harmful during drought conditions when flows are depressed and 
pollutants are more concentrated. Therefore, adequate water quality is 
essential for normal behavior, growth, and viability during all life 
stages of the Georgia pigtoe, interrupted rocksnail, and rough 
hornsnail.
Sites for Breeding, Reproduction, or Rearing
    Pleurocerid snails require clean hard surfaces, such as gravel, 
cobble, boulder, or bedrock, for laying eggs and for survival of 
juveniles (Bogan et al. 1995, p. 251). Excessive fine sediments or 
dense growth of filamentous algae can restrict or eliminate spawning 
sites and expose juveniles to entrainment (being swept away) or 
predation. Geomorphic instability may result in entrainment and loss of 
eggs by scouring currents or burial of eggs by excessive deposition. 
Therefore, stable shoals with low amounts of filamentous algae are 
essential to the conservation of the interrupted rocksnail and rough 
hornsnail.
    Freshwater mussels require a host fish for transformation of larval 
mussels (glochidia) to juvenile mussels (Williams et al. 2008, p. 68), 
and presence of the appropriate host fish is essential to the 
conservation of the Georgia pigtoe. The specific fish host(s) for the 
Georgia pigtoe is currently unknown, However, other species of mussels 
in the genus Pleurobema are known to parasitize various species of 
chubs, minnows, stonerollers, and other stream adapted fish species 
(Haag and Warren 2003).
    Juvenile Georgia pigtoe mussels require interstitial shoal habitats 
for growth and survival. Excessive sediments or dense growth of 
filamentous algae can expose juvenile mussels to entrainment or 
predation and be detrimental to the survival of juvenile mussels 
(Hartfield and Hartfield 1996). Geomorphic instability can result in 
the loss of interstitial habitats and juvenile mussels due to scouring 
or deposition (Hartfield 1993). Therefore, stable shoals with low to 
moderate amounts of filamentous algae growth are essential to the 
conservation of the Georgia pigtoe.
PCEs for the Georgia pigtoe, interrupted rocksnail, and rough hornsnail
    Based on the above needs and our current knowledge of the life 
history, biology, and ecology of the species, we have determined that 
the Georgia pigtoe's PCEs are:
    (1) Geomorphically stable stream and river channels and banks 
(channels that maintain lateral dimensions,

[[Page 31125]]

longitudinal profiles, and sinuosity patterns over time without an 
aggrading or degrading bed elevation).
    (2) A hydrologic flow regime (the magnitude, frequency, duration, 
and seasonality of discharge over time) necessary to maintain benthic 
habitats where the species are found. Unless other information becomes 
available, existing conditions at locations where the species occur 
will be considered as minimal flow requirements for survival.
    (3) Water quality (including temperature, pH, hardness, turbidity, 
oxygen content, and chemical constituents) that meets or exceeds the 
current aquatic life criteria established under the Clean Water Act (33 
U.S.C. 1251-1387).
    (4) Sand, gravel, cobble, boulder, or bedrock substrates with low 
to moderate amounts of fine sediment and attached filamentous algae.
    (5) The presence of fish host(s) for the Georgia pigtoe (currently 
unknown). Diverse assemblages of native chubs, minnows, stonerollers, 
and other stream adapted fish species will serve as a potential 
indication of presence of host fish.
    The PCEs required for the interrupted rocksnail are:
    (1) Geomorphically stable stream and river channels and banks 
(channels that maintain lateral dimensions, longitudinal profiles, and 
sinuosity patterns over time without an aggrading or degrading bed 
elevation).
    (2) A hydrologic flow regime (the magnitude, frequency, duration, 
and seasonality of discharge over time) necessary to maintain benthic 
habitats where the species are found. Unless other information becomes 
available, existing conditions at locations where the species occur 
will be considered as minimal flow requirements for survival.
    (3)Water quality (including temperature, pH, hardness, turbidity, 
oxygen content, and chemical constituents) that meets or exceeds the 
current aquatic life criteria established under the Clean Water Act (33 
U.S.C. 1251-1387).
    (4) Sand, gravel, cobble, boulder, or bedrock substrates with low 
to moderate amounts of fine sediment and attached filamentous algae.
    The PCEs required for the rough hornsnail are:
    (1) Geomorphically stable stream and river channels and banks 
(channels that maintain lateral dimensions, longitudinal profiles, and 
sinuosity patterns over time without an aggrading or degrading bed 
elevation).
    (2) A hydrologic flow regime (the magnitude, frequency, duration, 
and seasonality of discharge over time) necessary to maintain benthic 
habitats where the species are found. Unless other information becomes 
available, existing conditions at locations where the species occur 
will be considered as minimal flow requirements for survival.
    (3) Water quality (including temperature, pH, hardness, turbidity, 
oxygen content, and chemical constituents) that meets or exceeds the 
current aquatic life criteria established under the Clean Water Act (33 
U.S.C. 1251-1387).
    (4) Sand, gravel, cobble, boulder, or bedrock substrates with low 
to moderate amounts of fine sediment and attached filamentous algae.
    This proposed designation is designed for the conservation of the 
physical and biological features essential to the life history 
functions that were the basis for the proposal and the areas containing 
those features (that is, the PCEs in the appropriate spatial 
arrangement and quantity). Because not all life history functions 
require all the PCEs, not all PCEs may be present throughout the 
proposed critical habitat units.
    Units are designated based on sufficient PCEs being present to 
support at least one of the species' life history functions. Some areas 
contain all PCEs and support multiple life processes, while some areas 
may contain only a portion of the PCEs necessary to support the 
species' particular use of that habitat.
Special Management Considerations or Protections
    When designating critical habitat, we assess whether the areas 
within the geographical area occupied by the species at the time of 
listing contain features that are essential to the conservation of the 
species and whether those features may require special management 
considerations or protections. All of the critical habitat units 
proposed for these three species below, with the exception of a portion 
of Unit RH 1, have been designated as critical habitat for other 
mollusk species that are already listed under the Act. None of the 
areas proposed are presently under special management or protection 
provided by a legally operative management plan or agreement for the 
conservation of either the interrupted rocksnail, rough hornsnail, or 
Georgia pigtoe. Various activities in or adjacent to each of the 
critical habitat units described in this proposed rule may affect one 
or more of the PCEs. Some of these activities include, but are not 
limited to, those discussed in the ``Summary of Factors Affecting the 
Species,'' above. For example, three of the units described below 
(Units IR 1, IR 2, and RH 1 (which includes IR 3)) may require special 
management considerations due to detrimental effects of hydropower 
generation or lack of minimum flow releases from dams (see ``Factor A: 
Dams and Impoundments'' above). Features in all of the proposed 
critical habitat units may require special management due to threats 
posed by land-use runoff and point- and nonpoint-source water pollution 
(see ``Factor A: ``Water and Habitat Quality,'' and ``Factor D: 
Inadequacy of existing regulatory mechanisms,'' above). Other 
activities that may affect PCEs in the proposed critical habitat units 
include those listed in the ``Effects of Critical Habitat'' section as 
``Federal Activities that May Affect Critical Habitat and Require 
Consultation,'' below.
Criteria Used to Identify Proposed Critical Habitat
    We are proposing to designate as critical habitat all stream 
channels that are currently occupied by the species, as well as some 
specific areas not currently occupied but that were historically 
occupied, because we have determined that these additional areas are 
essential for the conservation of the Georgia pigtoe, interrupted 
rocksnail, and rough hornsnail, and that designating only occupied 
habitat is not sufficient to conserve each of these species.
    When identifying proposed critical habitat boundaries, we make 
every effort to avoid including developed areas such as lands covered 
by buildings, pavement, and other structures because such lands usually 
lack PCEs for endangered or threatened species. Areas proposed for 
critical habitat for the Georgia pigtoe, interrupted rocksnail, and 
rough hornsnail, below, include only stream channels within the 
ordinary high water line and do not contain any developed areas or 
structures.
Occupied Stream Reaches Proposed as Critical Habitat
    We have defined occupied habitat as those stream reaches known to 
be currently occupied by the Georgia pigtoe, interrupted rocksnail, or 
rough hornsnail. We used information from surveys and reports prepared 
by the U.S. Geological Survey, the Alabama Department of Conservation 
and Natural Resources, the Tennessee Aquarium, Alabama Geological 
Survey, Auburn University, University of Alabama, and Service field 
records to identify the specific locations occupied by the Georgia 
pigtoe, interrupted rocksnail, or rough hornsnail.

[[Page 31126]]

    Currently, occupied habitat for each of the three species is 
extremely limited and isolated. The Georgia pigtoe persists only in a 
restricted series of shoals in the Conasauga River (Johnson and Evans 
2000, p. 106). The interrupted rocksnail naturally survives in a short 
reach of the Oostanaula River in Gordon and Floyd Counties, Georgia, 
and population reintroductions have been attempted into a shoal of the 
Lower Coosa River, Elmore County, Alabama (ADCNR 2004, p. 33). The 
rough hornsnail is known from two small, localized, and isolated 
populations: Yellowleaf Creek, Shelby County, Alabama, and a short 
reach of the Lower Coosa River, Elmore County, Alabama (Sides 2005, p. 
40). We believe that all currently occupied areas contain features 
essential to the conservation of these species. With such limited 
distribution, each of these species are at a high risk of extinction 
and highly susceptible to stochastic events.
Unoccupied Stream Reaches Proposed as Critical Habitat
    The streams not currently occupied that we are proposing as 
critical habitat were all historically occupied. We believe that the 
designation of additional areas not known to be currently occupied by 
the Georgia pigtoe, interrupted rocksnail, or rough hornsnail is 
essential for their conservation because:
    (1) The range of each species has been severely curtailed, occupied 
habitats are limited and isolated, and population sizes are extremely 
small for each species. While occupied units provide habitat for 
current populations, they are at high risk of extirpation and 
extinction from stochastic events, whether periodic natural events or 
existing or potential human-induced events (see ``Summary of Factors 
Affecting the Species''). The inclusion of essential unoccupied areas 
will provide habitat for population reintroduction and will decrease 
the risk of extinction for each species.
    (2) The essential unoccupied areas may offer habitat that is 
superior to that in the occupied units (the potential viability of the 
mollusks in unoccupied units may be higher) because the essential 
unoccupied areas may be faced with fewer and more easily treated 
threats than the occupied units (see discussion under ``Factor A: Dams 
and Impoundments'').
    (3) The protection of PCEs in currently occupied areas is directly 
related to conditions in adjacent unoccupied stream reaches (such as 
the Oostanaula and Lower Coosa Rivers).
    Based on the best scientific data available, we believe that areas 
that are not currently occupied by the Georgia pigtoe, interrupted 
rocksnail, or rough hornsnail are essential for their conservation.

Length of Occupied Stream Reaches

    Following the identification of occupied stream reaches, the next 
step was to delineate the length of upstream and downstream reaches of 
known occupied areas to determine the length of stream reaches that are 
needed for the conservation of the populations for each species. All 
known occurrences for each species are extremely localized, and rare 
aquatic snails and mussels can be difficult to locate. In addition, 
creek and river habitats are highly dependent upon upstream and 
downstream channel habitat conditions for their maintenance. Therefore, 
where more than one occurrence record of a particular species was found 
within a stream reach, we considered the entire reach between the 
uppermost and lowermost locations as occupied habitat, as discussed 
below.
Georgia pigtoe
    The Georgia pigtoe is currently known to survive only in a 52-km 
(32-mi) reach of the Upper Conasauga River extending from Polk County, 
Tennessee, downstream into Murray and Whitfield Counties, Georgia 
(Johnson and Evans 2000, p. 106; Evans 2001, pp. 33-34). The Georgia 
pigtoe has been recently collected from three shoals within this reach: 
one located at each end of the reach, and one additional site in the 
lower third of the reach. Other shoals within the reach continue to be 
inhabited by a diverse mussel community, including the federally 
endangered triangular kidneyshell and southern pigtoe and the 
threatened fine-lined pocketbook. These species historically co-
occurred in the same shoal habitats with the Georgia pigtoe, and their 
persistence indicates the presence of PCEs for the pigtoe throughout 
the reach. Therefore, we consider the entire 52-km (32-mi) reach 
between the uppermost and lowermost recent collection sites for the 
Georgia pigtoe as occupied habitat. In the area proposed for critical 
habitat below, boundaries extend from the nearest downstream landmark 
at both of ends of the reach.
Interrupted rocksnail
    The interrupted rocksnail is known to survive in several shoals 
along a 12-km (7.4-mi) reach of the Oostanaula River between Ship 
Island and the confluence of Armuchee Creek, Gordon-Floyd County, 
Georgia (Johnson and Evans 2000, pp. 45-46; Johnson and Evans 2001, pp. 
2, 25). Although rocksnails live attached to the stream bottom, they 
are small and often difficult to locate when their population numbers 
are low. Therefore, we consider the reach of the Oostanaula River 
between Ship Island and the confluence of Armuchee Creek as habitat 
occupied by interrupted rocksnail. Attempts to reintroduce the species 
into the Lower Coosa River, Elmore County, Alabama, have also been made 
by the ADCNR. Although we do not yet know if this population is viable, 
it is within the range of the interrupted rocksnail as proposed in this 
listing; therefore, we are considering the 1-km (0.6-mi) localized area 
in the Lower Coosa River, where the species was reintroduced, as 
occupied habitat. ADCNR attempted to reintroduce the interrupted 
rocksnail into Gray Island Shoals in the Lower Coosa River, about 3.2 
km (2 mi) below Jordan Dam, Elmore County, Alabama. Although we do not 
yet know if this reintroduced population is viable, it is within the 
historical range of the interrupted rocksnail as proposed in this 
listing, and we are considering the 1-km (0.6-mi) reach encompassing 
Gray Island Shoals in the Lower Coosa River as occupied habitat.
Rough hornsnail
    The rough hornsnail is known to survive at only two locations. One 
of these consists of a population known from only a few hundred meters 
of stream in Yellowleaf Creek near Alabama Highway 25, Shelby County, 
Alabama, and we consider Yellowleaf Creek 1.6 km (1.0 mi) above and 1.6 
km (1.0 mi) below Alabama Highway 25 as habitat occupied by the rough 
hornsnail. In addition, collections in the 1990s in the Lower Coosa 
River, Elmore County, Alabama, show the rough hornsnail extended from 
the shoals below Jordan Dam, downstream to just below the Fall Line at 
Wetumpka, Alabama (FLMNH 2006). Therefore, we consider this 14-km (8-
mi) reach as habitat occupied by the rough hornsnail.

Stream Reaches Not Currently Occupied

    In identifying unoccupied stream reaches that are essential to the 
conservation of each species (Georgia pigtoe, interrupted rocksnail, 
and rough hornsnail), we first considered the availability of potential 
habitat throughout their historical ranges that may be suitable for the 
survival and persistence of each species. A large proportion of the 
streams that formerly supported each species have been modified by dams 
and their impounded waters, and we eliminated these areas from 
consideration, because none of these species can survive under the

[[Page 31127]]

modified conditions (see ``Primary Constituent Elements'' section, 
above). We also eliminated from consideration free-flowing streams 
without any historical records of occurrence. We eliminated from 
consideration other streams with historical occurrence records because 
of limited habitat availability, isolation, degraded habitat, or low 
management value or potential (such as Coosawattee River and Etowah 
River).
    All of the areas proposed as critical habitat that are currently 
not known to be occupied meet one or more of the following criteria:
    (1 The stream habitat contains sufficient PCEs (for example, such 
characteristics as geomorphically stable channels, perennial water 
flows, adequate water quality, and appropriate benthic substrates) to 
support life history functions of the mollusks (all proposed unoccupied 
critical habitat units);
    (2) The stream supports diverse aquatic molluscan communities, 
including the presence of closely related species requiring PCEs 
similar to the Georgia pigtoe, interrupted rocksnail, and rough 
hornsnail (all proposed unoccupied critical habitat units);
    (3) The stream reaches are adjacent to currently occupied areas 
where there is potential for natural dispersal and reoccupation by the 
Georgia pigtoe, interrupted rocksnail, or rough hornsnail (Oostanaula 
River, Lower Coosa River, and Yellowleaf Creek);
    (4) The stream reaches lack major anthropogenic disturbance 
(Hatchet Creek);
    (5) Areas are remote from currently occupied areas and have 
experienced improvements in water quality or quantity during the past 
decades due to implementation of minimum flows below dams, changes in 
adjacent land uses, or implementation of the Clean Water Act (Coosa 
River below Weiss Dam and Jordan Dam, Terrapin Creek, and Hatchet 
Creek); and
    (6) The stream reaches have potential for reoccupation by the 
species through future reintroduction efforts (all proposed unoccupied 
critical habitat units).
    Based on the above factors, all unoccupied stream reaches included 
in the proposed designations for each of these three species are 
essential to their conservation.
Georgia pigtoe
    We have identified 101 km (63 mi) of habitat in two stream reaches 
that are currently unoccupied by the Georgia pigtoe and that meet 
several of the criteria for designation as critical habitat. Historical 
records of Georgia pigtoe occur from the Coosa River near the present 
location of Weiss Dam and from Terrapin Creek, from its confluence with 
the Coosa River upstream to the vicinity of Alabama Highway 9. Terrapin 
Creek flows into the Coosa River approximately 11 km (7 mi) below Weiss 
Dam in Cherokee County, Alabama. Together these two confluent stream 
reaches encompass 35 km (22 mi) of stream habitat that meet Criteria 1, 
2, 5, 6, and 7 listed above in this section. Terrapin Creek and this 
short reach of the Coosa River support diverse mollusk and fish 
communities. Water quality in Terrapin Creek meets current State 
criteria for Fish and Wildlife. The Mobile River Basin Mollusk 
Restoration Committee (2008, p. 36) recognizes this reach of the Coosa 
River and Terrapin Creek as an appropriate reintroduction site for the 
Georgia pigtoe. Based on the information we have to date, which does 
not necessarily suggest there is an increased probability of Georgia 
pigtoe conservation in specific areas within the reach, we propose to 
designate the entire reach of Terrapin Creek and the Coosa River as 
critical habitat.
    Historical records of Georgia pigtoe occur from an approximately 
66-km (41-mi) reach of Hatchet Creek between Clay County Road 4 
downstream to the confluence with Swamp Creek in Coosa County, Alabama. 
This stream reach meets Criteria 1, 2, 4, 5, 6, and 7 listed above in 
this section and has been identified by the Mobile River Basin Mollusk 
Restoration Committee (2008, p. 40) as having high conservation 
potential for the reintroduction of imperiled mollusks. Hatchet Creek 
supports diverse mollusk and fish communities and has been designated 
as an Outstanding Alabama Water, the highest protective classification 
assigned by the State. Based on the information we have to date, which 
does not necessarily suggest there is an increased probability of 
Georgia pigtoe conservation in specific areas within the reach, we 
propose to designate the entire reach of Hatchet Creek as critical 
habitat.
Interrupted rocksnail
    We have identified 88 km (55 mi) of habitat in three stream reaches 
that are currently unoccupied by the interrupted rocksnail and that 
meet several of the criteria for designation as unoccupied habitat. The 
Coosa River from Weiss Dam to just below the confluence of Terrapin 
Creek (11 km (7 mi)) is within the historical range of the interrupted 
rocksnail, and meets Criteria 1, 2, 5, 6, and 7 listed above in this 
section. Several mollusk species requiring similar PCEs currently 
inhabit a portion of the reach. Projected minimum flows (Weiss Bypass 
Working Group 2005, pp. 6-8) will improve PCEs in the remainder of the 
reach, and reservoir-stored water will provide protection from nonpoint 
source pollution and reduce the potential of stochastic threats. The 
Mobile River Basin Mollusk Restoration Committee (2008, p. 53) 
recognizes this reach of the Coosa River as an appropriate 
reintroduction sites for interrupted rocksnail.
    The interrupted rocksnail is currently known to inhabit shoals 
along a 12-km (7.4-mi) reach of the Oostanaula River between Ship 
Island and the Confluence of Armuchee Creek, Gordon and Floyd Counties, 
Georgia. However, appropriate habitat extends approximately 49 km (30 
mi) above Ship Island to the Conasuaga-Coosawattee confluence in Gordon 
County, Georgia, and approximately 16 km (10 mi) below the confluence 
of Armuchee Creek to the Georgia Highway 1 Loop in Floyd County, 
Georgia. This unoccupied area encompasses an additional 65 km (40 mi) 
of river habitat that meets Criteria 1, 2, 3, 6, and 7 listed above in 
this section. The unoccupied upstream and downstream reaches of the 
Oostanaula River contain one or more of the PCEs required by the 
species, including geomorphically stable channels and natural flows. 
They are adjacent to areas currently occupied by interrupted rocksnail, 
and there is potential for natural dispersal and re-occupation by the 
Georgia pigtoe. These areas are also currently occupied by other 
mollusk species with similar habitat requirements.
    The Lower Coosa River below Jordan Dam is within the historical 
range of the interrupted rocksnail, and a small population of the 
species has been reintroduced into a shoal there (ADCNR, p. 33). 
Apparently suitable habitat extends approximately 13 km (8 mi) from the 
tailwaters of Jordan Dam to Alabama Highway 111 in Elmore County, 
Alabama. This reach meets Criteria 1, 2, 3, 5, 6, and 7 listed above in 
this section. The steep river gradient below the dam to the Fall Line 
at Alabama Highway 111 in Wetumpka results in the presence of numerous 
high-quality and stable shoals and pools characteristic of habitats 
formerly inhabited by the rocksnail. The reach is occupied by other 
species of pleurocerid snails, as well as a diverse mussel fauna, 
indicating the presence of PCEs in this reach. Minimum flows that have 
been established from Jordan Dam have eliminated historical threats, 
such as seasonal loss of flow and low dissolved

[[Page 31128]]

oxygen levels. The Mobile River Basin Mollusk Restoration Committee 
(2008, p. 53) recognizes this reach of the Coosa River as an 
appropriate reintroduction site for interrupted rocksnail, and the 
ADCNR has initiated attempts to reintroduce the species to the reach.
Rough hornsnail
    We have identified 8.5 km (7 mi) of habitat in two stream reaches 
that are unoccupied by the rough hornsnail but that meet Criteria 1, 2, 
3, 6, and 7 listed above in this section. The species inhabits a 14-km 
(8-mi) reach of the Lower Coosa River below Jordan Dam; however, 
appropriate habitat extends an additional 7 km (5 mi) downstream of 
currently occupied areas. This stream reach is available for natural 
recolonization and contains one or more of the PCEs required by the 
rough hornsnail, including a geomorphically stable channel and adequate 
water quality and substrate, as indicated by the presence of closely 
related pleurocerids and other mollusk species with similar habitat 
requirements.
    The rough hornsnail currently inhabits a small area in Yellowleaf 
Creek near Alabama Highway 25 in Shelby County, Alabama. A 3.5-km (2-
mi) reach upstream of this area is available for natural 
recolonization. This reach is currently inhabited by closely related 
pleurocerids and other mollusk species with similar habitat 
requirements and contains one or more of the PCEs required by the rough 
hornsnail, including a geomorphically stable channel, a natural 
hydrograph, and adequate water quality and substrate.

Proposed Critical Habitat Designation

    We are proposing three units as critical habitat for the Georgia 
pigtoe (GP 1, 2, and 3), three units for interrupted rocksnail (IR 1, 
2, and 3), and two units for rough hornsnail (RH 1 and 2). The critical 
habitat areas described below constitute our best assessment of areas 
that currently meet the definition of critical habitat for the Georgia 
pigtoe, interrupted rocksnail, and rough hornsnail. Table 1 identifies 
the proposed units for each species; shows the occupancy of the units, 
the approximate extent proposed as critical habitat for the Georgia 
pigtoe (GP), interrupted rocksnail (IR), and rough hornsnail (RH); and 
provides information on the ownership of lands within the proposed 
unit. Critical habitat is proposed for the stream channel within the 
ordinary high water line only. In Alabama and Georgia, the State owns 
navigable stream bottoms within the ordinary high water line, and all 
proposed units in Alabama and Georgia are considered navigable. In 
Tennessee, the riparian landowner owns the stream bottom to the middle 
of the channel.

    TABLE 1. Occupancy and ownership of proposed critical habitat units for Georgia pigtoe (GP), interrupted
                                    rocksnail (IR), and rough hornsnail (RH)
----------------------------------------------------------------------------------------------------------------
                                                                           Private Ownership    State Ownership
              Unit                     Location            Occupancy       River Kilometers    River Kilometers
                                                                                (Miles)             (Miles)
----------------------------------------------------------------------------------------------------------------
GP 1                              Conasauga River     Occupied            5 (3)               47 (29)
----------------------------------------------------------------------------------------------------------------
GP 2                              Terrapin Creek and  Unoccupied          0                   35 (22)\1\
                                   Coosa River
----------------------------------------------------------------------------------------------------------------
GP 3                              Hatchet Creek       Unoccupied          0                   66 (41)
----------------------------------------------------------------------------------------------------------------
Total                                                                     5 (3)               148 (92)
----------------------------------------------------------------------------------------------------------------
IR 1                              Coosa River         Unoccupied          0                   11 (7)\1\
----------------------------------------------------------------------------------------------------------------
IR 2                              Oostanaula River    Occupied            0                   12 (7.4)
                                 -------------------------------------------------------------------------------
                                                      Unoccupied          0                   65 (40.6)
----------------------------------------------------------------------------------------------------------------
IR 3                              Lower Coosa River   Occupied            0                   1 (0.6)\2\
                                 -------------------------------------------------------------------------------
                                                      Unoccupied          0                   12 (7.4)2
----------------------------------------------------------------------------------------------------------------
Total                                                                     0                   101 (63)
----------------------------------------------------------------------------------------------------------------
RH 1                              Lower Coosa River   Occupied            0                   14 (9)2
                                 -------------------------------------------------------------------------------
                                                      Unoccupied          0                   7 (4)
----------------------------------------------------------------------------------------------------------------
RH 2                              Yellowleaf Creek    Occupied            0                   3.2 (2)
                                 -------------------------------------------------------------------------------
                                                      Unoccupied          0                   3.2 (2)
----------------------------------------------------------------------------------------------------------------
Total                                                                     0                   27.4 (17)
----------------------------------------------------------------------------------------------------------------
\1\ IR 1 overlaps in part with GP 2.
\2\ IR 3 overlaps in part with RH 1. See Unit descriptions, below.

    We present brief descriptions of all units and reasons why they 
meet the definition of critical habitat for each species below. The 
proposed critical habitat units include the creek and river channels 
within the ordinary high water line. For this purpose, we have applied 
the definition found at 33 CFR 329.11, and consider the ordinary high 
water line on nontidal rivers to be 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. For each stream reach 
proposed as a critical habitat unit, the upstream and

[[Page 31129]]

downstream boundaries are described generally below; more precise 
estimates are provided in the Proposed Regulation Promulgation section 
at the end of this proposed rule.
Unit GP 1: Conasauga River, Bradley and Polk Counties, Tennessee, and 
Murray and Whitfield Counties, Georgia
    Unit 1 for the Georgia pigtoe includes 52 km (32 mi) of the Upper 
Conasauga River from the confluence of Minnewaga Creek near Willis 
Springs, Polk County, Tennessee, downstream to U.S. Highway 76 in 
Murray and Whitfield Counties, Georgia. Critical habitat is proposed 
for the stream channel within the ordinary high water line only. In 
Tennessee, the riparian landowner owns the stream bottom to the middle 
of the channel. Therefore, 5 km (3 mi) of GP 1 in Tennessee is 
privately owned. In Georgia, the State owns navigable stream bottoms 
within the ordinary high water line, and the Conasauga is considered 
navigable. Therefore, the State of Georgia owns 47 km (29 mi) of Unit 
GP 1.
    The Georgia pigtoe has been collected from three shoals within the 
reach of the Conasauga River proposed as GP 1, one located at each end 
of the reach and one site in between (Johnson and Evans 2000, p. 106; 
Evans 2001, pp. 33-34). Therefore, we consider the entire reach of the 
Conasauga River that composes GP 1 as occupied. Other shoals within the 
reach continue to be inhabited by a diverse mussel community, including 
the endangered triangular kidneyshell and southern pigtoe and the 
threatened fine-lined pocketbook. These species historically co-
occurred in the same shoal habitats with the Georgia pigtoe, they have 
similar habitat requirements, and their persistence indicates the 
presence of PCEs 1, 2, 3, and 4 for the pigtoe. The persistence of the 
Georgia pigtoe within three shoals of this reach also indicates the 
presence of an appropriate fish host (PCE 5). This small population of 
Georgia pigtoe is at a high risk of extinction due to changes in flow, 
habitat or water quality, and stochastic events such as drought. 
Threats to the Georgia pigtoe and its habitat that may require special 
management of the PCEs include the potential of anthropogenic 
activities (such as channelization, impoundment, and channel 
excavation) that could cause aggradation or degradation of the channel 
bed elevation or significant bank erosion; the potential of significant 
changes in the existing flow regime due to such activities as 
impoundment, water diversion, or water withdrawal; the potential of 
significant alteration of water chemistry or water quality; and the 
potential of significant changes in stream bed material composition and 
quality by activities such as construction projects, livestock grazing, 
timber harvesting, off-road vehicle use, and other watershed and 
floodplain disturbances that release sediments or nutrients into the 
water.
Unit GP 2: Terrapin Creek and Coosa River, Cherokee County, Alabama
    Unit 2 for the Georgia pigtoe includes 24 km (15 mi) of Terrapin 
Creek from Alabama Highway 9 downstream to its confluence with the 
Coosa River, and 11 km (7 mi) of the Coosa River from Weiss Dam 
downstream to approximately 1.6 km (1 mi) below the confluence of 
Terrapin Creek in Cherokee County, Alabama. The State of Alabama owns 
navigable stream bottoms within the ordinary high water line, and both 
Lower Terrapin Creek and the Coosa River are considered navigable 
streams.
    The Georgia pigtoe is not currently known to occur in Terrapin 
Creek or the Coosa River. However, Unit 2 is essential to the 
conservation of the Georgia pigtoe due to the high degree of stochastic 
threats to the single surviving population in the Conasauga River, and 
the need to re-establish the species within other portions of its 
historical range in order to reduce threats from stochastic events.
    Lower Terrapin Creek and the Coosa River are within the species' 
historical range, and we consider them to be essential to the 
conservation of the Georgia pigtoe. Terrapin Creek flows into the Coosa 
River below Weiss Dam. Terrapin Creek continues to support a diverse 
mollusk assemblage, including the endangered southern pigtoe, a closely 
related species that co-occurs with the Georgia pigtoe in the Conasauga 
River, indicating the presence of PCEs 1, 2, 3, and 4. The endangered 
southern clubshell, the threatened fine-lined pocketbook, and other 
mussel and snail species requiring PCEs 1, 2, 3, and 4 similar to the 
Georgia pigtoe continue to survive in the Coosa River just below the 
confluence of Terrapin Creek. Additionally, a diverse fish fauna, 
including potential fish hosts for the Georgia pigtoe (PCE 5), is known 
from Terrapin Creek and Coosa River.
    Minimum flows from Weiss Dam into the Coosa River will be 
implemented upon completion of the Alabama Power Company Coosa River 
hydropower relicensing process with FERC (Weiss Bypass Working Group 
2005, pp. 6-8) currently in progress. These minimum flows will improve 
the PCEs necessary for the survival of the Georgia pigtoe in the Coosa 
River, particularly above the confluence with Terrapin Creek. Because 
the minimum flows will originate from the large reservoir impounded by 
Weiss Dam, there is little threat of nonpoint source pollution and 
reduced potential of stochastic threats, such as drought and spills. 
ADCNR recognizes this reach of the Coosa River as having high 
conservation potential for imperiled mollusks in Alabama and is 
planning to reintroduce imperiled mollusks, including the Georgia 
pigtoe, following initiation of minimum flows. Over the past few 
decades, changes in land uses, implementation of best management 
practices for agriculture and forestry activities in the watershed, and 
implementation of State water quality standards have resulted in 
improved water quality and shoal habitats in Terrapin Creek. The Mobile 
River Basin Mollusk Restoration Committee (2008, p. 40) recognizes 
Terrapin Creek as an appropriate reintroduction opportunity for the 
Georgia pigtoe.
Unit GP 3: Hatchet Creek, Coosa and Clay Counties, Alabama
    Unit 3 for the Georgia pigtoe includes approximately 66 km (41 mi) 
of Hatchet Creek, extending from Clay County Road 4, Clay County, 
downstream to the confluence of Swamp Creek at Coosa County Road 29, 
Coosa County, Alabama. The State of Alabama owns navigable stream 
bottoms within the ordinary high water line, and Hatchet Creek is 
considered navigable.
    The Georgia pigtoe does not currently occupy Hatchet Creek. 
However, historical records of the species show their presence in this 
stream from its confluence with the Coosa River, Coosa County, upstream 
into Clay County, Alabama. An extensive reach of Hatchet Creek is 
occupied by the threatened fine-lined pocketbook, along with other 
mollusk species that currently or historically co-occur with Georgia 
pigtoe, indicating the presence of PCEs 1, 2, 3, and 4. A diverse fish 
fauna, including several potential fish hosts for the pigtoe (PCE 5), 
is also known to inhabit Hatchet Creek. Water quality and shoal 
habitats in this stream have improved relative to past historical 
conditions due to changes in land uses, implementation of best 
management practices in agriculture and forestry activities in the 
watershed, and implementation of State water quality standards. Due to 
these improvements, Hatchet Creek has been designated as an Outstanding 
Alabama Water, which also provides for increased water quality 
protections. The Mobile River Basin Mollusk Restoration Committee 
(2008, p. 40) recognizes Hatchet Creek as

[[Page 31130]]

having high conservation potential for reintroduction of the Georgia 
pigtoe.
    Re-establishing Georgia pigtoe in Hatchet Creek will significantly 
reduce the level of stochastic threats to the species' survival and is 
essential to the conservation of the species. We do not know which 
specific shoals or reaches of Hatchet Creek may be capable of 
supporting the Georgia pigtoe. Therefore, we propose to designate all 
apparently suitable habitat within the historical range of the species 
in Hatchet Creek as critical habitat essential to the conservation of 
Georgia pigtoe.
Unit IR 1: Coosa River, Cherokee County, Alabama (overlaps in part with 
GP 2, described above)
    Unit 1 for the interrupted rocksnail includes approximately 11 km 
(7 mi) of the Coosa River extending from Weiss Dam downstream to about 
1.6 km (1 mi) below the confluence of Terrapin Creek, Cherokee County, 
Alabama. The State of Alabama owns navigable stream bottoms within the 
ordinary high water line, and the Coosa River is considered navigable.
    The interrupted rocksnail historically inhabited the Coosa River in 
Cherokee County. Although the species does not currently occupy the 
area, Unit 1 is essential to the conservation of the interrupted 
rocksnail due to the high degree of stochastic threats to the single 
surviving population in the Ostanaula River and the need to re-
establish the species within other portions of its historical range. 
The presence of the endangered southern clubshell, the threatened fine-
lined pocketbook, and other mussel and snail species in the Coosa River 
at and below the confluence of Terrapin Creek indicates the presence of 
PCEs 1, 2, 3, and 4 for the interrupted rocksnail.
    Minimum flows from Weiss Dam into the Coosa River will be 
implemented upon completion of the Alabama Power Company Coosa River 
hydropower relicensing process with FERC (Weiss Bypass Working Group 
2005, pp. 6-8) currently in progress. These minimum flows will improve 
the PCEs necessary for the survival of the interrupted rocksnail in 
about 11 km (7 mi) of the Coosa River, between Weiss Dam downstream to 
the confluence with Terrapin Creek. Implementation of minimum flows 
from Weiss Dam (Weiss Bypass Working Group 2005, pp. 6-8) will improve 
PCEs necessary for the survival of the interrupted rocksnail. The 
majority of flow into the reach above the confluence of Terrapin Creek 
originates from Weiss Dam. Therefore, there is little threat of 
nonpoint source pollution, and reduced potential of stochastic threats 
such as drought and spills. ADCNR recognizes this reach as having high 
conservation potential for imperiled mollusks in Alabama and is 
planning to reintroduce imperiled mollusk species, including the 
interrupted rocksnail, into the reach following initiation of minimum 
flows. Re-establishing the interrupted rocksnail into the Coosa River 
will significantly reduce stochastic threats to the survival of the 
species and is essential to its conservation.
Unit IR 2: Oostanaula River, Gordon and Floyd Counties, Georgia
    Unit 2 for the interrupted rocksnail includes approximately 77 km 
(48 mi) of the Oostanaula River from the Conasauga-Coosawattee 
confluence in Gordon County, downstream to Georgia Highway 1 loop in 
Floyd County, Georgia. The State of Georgia owns navigable stream 
bottoms within the ordinary high water line, and the Oostanaula River 
is considered navigable.
    The interrupted rocksnail occupies shoals along a 12-km (7.4-mi) 
reach of the Oostanaula River, extending from the confluence of Johns 
Creek in Gordon and Floyd Counties, downstream to the confluence of 
Armuchee Creek in Floyd County, Georgia. Threats to the interrupted 
rocksnail and its habitat in the Oostanaula River that may require 
special management of the PCEs include the potential of activities 
(such as channelization, impoundment, and channel excavation) that 
could cause aggradation or degradation of the channel bed elevation or 
significant bank erosion; the potential of significant changes in the 
existing flow regime due to activities such as impoundment, hydropower 
generation, water diversion, or water withdrawal; the potential of 
significant alteration of water chemistry or water quality; and the 
potential of significant changes in stream bed material composition and 
quality by activities such as construction projects, livestock grazing, 
timber harvesting, off-road vehicle use, and other watershed and 
floodplain disturbances that release sediments or nutrients into the 
water.
    Although there are no recent collections of the species from shoal 
habitats above and below the currently inhabited reach, these currently 
unoccupied areas contain three of the PCEs required by the species, 
including geomorphically stable stream channels, natural flows, and 
appropriate substrates (PCEs 1, 2, and 4). The presence of other 
mollusk species with similar habitat requirements as the interrupted 
rocksnail in this reach, including the endangered triangular 
kidneyshell, along with more common species of pleurocerid snails, also 
indicates the potentially suitable presence of appropriate water 
quality (PCE 3). Shoals within the 65 km (40.6 mi) of currently 
unoccupied reaches of the Oostanaula River are available to natural 
recolonization of the species. Expanding the range of the interrupted 
rocksnail into adjacent shoals in the river would greatly reduce the 
degree of threat from stochastic events, and is essential to the 
conservation of the interrupted rocksnail.
Unit IR 3: Lower Coosa River, Elmore County, Alabama
    Unit 3 for the interrupted rocksnail includes 13 km (8 mi) of the 
Lower Coosa River between Jordan Dam and Alabama Highway 111 in Elmore 
County, Alabama. The State of Alabama owns navigable stream bottoms 
within the ordinary high water line, and the Coosa River is considered 
navigable.
    The Lower Coosa River is within the historical range of the 
species, and a small population of the interrupted rocksnail has been 
reintroduced into a 1-km (0.6-mi) portion of a shoal there (ADCNR 2004, 
p 33). However, this reintroduced population will likely require 
augmentations over several years before population size can reach self-
sustainable levels. The remaining 12 km (7.4 mi) of this reach, from 
Jordan Dam downstream to the Fall Line at Wetumpka, contains numerous 
high-quality shoals and pools characteristic of the large river 
habitats historically occupied by the species. Several other species of 
pleurocerid snails, the endangered tulotoma snail, and a diverse mussel 
fauna are currently found throughout the reach, indicating the presence 
and suitability of PCEs 1, 2, 3, and 4 for the interrupted rocksnail in 
this reach. Historical threats, including seasonal loss of flow and low 
dissolved oxygen, were eliminated in 1990 by implementation of minimum 
flows from Jordan Dam by the Alabama Power Company. As noted, ADCNR 
recognizes the Lower Coosa River as an appropriate location for 
imperiled mollusk reintroductions and has begun efforts to reestablish 
the interrupted rocksnail into this reach. Due to the extremely limited 
distribution of the interrupted rocksnail and the high degree of 
stochastic threats to the single natural population, reestablishing the 
species in the Lower Coosa River is essential to the conservation of 
the interrupted rocksnail.

[[Page 31131]]

Unit RH 1: Lower Coosa River, Elmore County, Alabama (overlaps in part 
with IR 3, described above)
    Unit 1 for the rough hornsnail includes 21 km (13 mi) of the Lower 
Coosa River extending from Jordan Dam, downstream to the confluence of 
the Tallapoosa River in Elmore County, Alabama. The State of Alabama 
owns navigable stream bottoms within the ordinary high water line, and 
the Coosa River is considered navigable. We believe PCEs 1, 2, 3, and 4 
to be suitable throughout the reach, due to the presence of rough 
hornsnail colonies or other closely related pleurocerid snail species 
that are known to co-occur with the hornsnail and have similar habitat 
requirements.
    Early 1990 records of rough hornsnail from the reach of the Coosa 
River between Jordan Dam and the Fall Line (FLMNH 2006), and more 
recent records of the hornsnail extending 2 km (1.2 mi) below the Fall 
Line (J. Garner and P. Hartfield pers. obsv. 2001), indicate an 
occupied range of 14 km (9 mi) in the Lower Coosa River. An additional 
7-km (4-mi) channel reach extending downstream to the confluence of the 
Tallapoosa River is not currently occupied. This downstream unoccupied 
area is available for natural recolonization, and contains PCEs 1, 2, 
3, and 4, including a geomorphically stable channel, and adequate flow, 
water quality, and substrate, as indicated by the presence of closely 
related pleurocerids and other mollusk species with similar habitat 
requirements. Expanding the range of rough hornsnail into the currently 
unoccupied downstream habitat would reduce the level of stochastic 
threats to the species, and is essential to its conservation.
    Threats to the rough hornsnail and its habitat in the Coosa River 
that may require special management of the PCEs include the potential 
of activities (such as channelization, impoundment, and channel 
excavation) that could cause aggradation or degradation of the channel 
bed elevation or significant bank erosion; the potential of significant 
changes in the existing flow regime due to such activities as 
hydropower generation, water diversion, or water withdrawal; the 
potential of significant alteration of water chemistry or water quality 
due to discharges or land use activities; and the potential of 
significant changes in stream bed material composition and quality by 
activities such as construction projects, livestock grazing, timber 
harvesting, and other watershed and floodplain disturbances that 
release sediments or nutrients into the water.
Unit RH 2: Yellowleaf Creek, Shelby County, Alabama
    Unit 2 for the rough hornsnail includes approximately 6.4 km (4 mi) 
of the Yellowleaf Creek channel from the confluence of Morgan Creek, 
downstream to 1.6 km (1 mi) below the Alabama Highway 25 crossing in 
Shelby County, Alabama. The State of Alabama owns navigable stream 
bottoms within the ordinary high water line, and the lower reach of 
Yellowleaf Creek is considered navigable.
    The rough hornsnail occupies a 3.2-km (2-mi) reach of Yellowleaf 
Creek above and below Alabama Highway 25. We are also proposing a 3.2-
km (2-mi) reach of currently unoccupied habitat above this reach. This 
upstream reach is characterized by a stable channel, natural flows, and 
appropriate water quality and substrates (PCEs 1, 2, 3, and 4). The 
shoals and pools within the unoccupied reach are inhabited by the 
endangered triangular kidneyshell, southern clubshell, and cylindrical 
lioplax snail, as well as other more common species of mussels and 
snails that require similar PCEs as the hornsnail. Increasing the range 
and numbers of the rough hornsnail into this currently unoccupied area 
will decrease the vulnerability of this population and the species to 
stochastic threats, and is essential to its conservation.
    Threats to the rough hornsnail and its habitat in Yellowleaf Creek 
that may require special management of PCEs 1, 2, 3, and 4 include the 
potential of activities (such as channelization, impoundment, and 
channel excavation) that could cause aggradation or degradation of the 
channel bed elevation or significant bank erosion; the potential of 
significant changes in the existing flow regime due to such activities 
as water diversion or water withdrawal; and the potential of 
significant alteration of water chemistry or water quality due to 
discharges or nonpoint source pollution; the potential of significant 
changes in stream bed material composition and quality by activities 
such as construction projects, livestock grazing, timber harvesting, 
and other watershed and floodplain disturbances that release sediments 
or nutrients into the water.

Effects of Critical Habitat Designation

Section 7 Consultation
    Section 7(a)(2) of the Act requires Federal agencies, including the 
Service, to ensure that actions they fund, authorize, or carry out are 
not likely to destroy or adversely modify critical habitat. Decisions 
by the courts of appeals for the Fifth and Ninth Circuits 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, 245 F.3d 434, 442 (5th Cir. 2001)), and we 
do not rely on this regulatory definition when analyzing whether an 
action is likely to destroy or adversely modify critical habitat. Under 
the 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. Section 7(a)(4) of the Act requires Federal agencies to 
confer with the Service on any action that is likely to jeopardize the 
continued existence of a species proposed for listing or result in 
destruction or adverse modification of proposed critical habitat. This 
is a procedural requirement only, as any conservation recommendations 
in a conference report or opinion are strictly advisory.
    The primary utility of the conference procedures is to allow a 
Federal agency to maximize its opportunity to adequately consider 
species proposed for listing and proposed critical habitat and, if we 
list the proposed species or designate proposed critical habitat, to 
avoid potential delays in implementing their proposed action because of 
the section 7(a)(2) compliance process. We may conduct conferences 
either informally or formally. We typically use informal conferences as 
a means of providing advisory conservation recommendations to assist 
the agency in eliminating conflicts that the proposed action may cause. 
We typically use formal conferences when we or the Federal agency 
believes the proposed action is likely to jeopardize the continued 
existence of the species proposed for listing or adversely modify 
proposed critical habitat.
    We generally provide the results of an informal conference in a 
conference report, while we provide the results of a formal conference 
in a conference opinion. We typically prepare conference opinions on 
proposed species or critical habitat in accordance with procedures 
contained at 50 CFR 402.14, as if the proposed species were already 
listed or the proposed critical habitat was already designated. We may 
adopt the conference opinion as the

[[Page 31132]]

biological opinion when the species is listed or the critical habitat 
is designated, if no substantial new information or changes in the 
action alter the content of the opinion (see 50 CFR 402.10(d)).
    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. Activities on State, tribal, local, or private 
lands requiring a Federal permit (such as a permit from the U.S. Army 
Corps of Engineers under section 404 of the Clean Water Act (33 U.S.C. 
1251 et seq.) or a permit from the Service under section 10 of the Act) 
or involving some other Federal action (such as funding from the 
Federal Highway Administration, Federal Aviation Administration, or the 
Federal Emergency Management Agency) are subject to the section 7(a)(2) 
consultation process. Federal actions not affecting listed species or 
critical habitat, and actions on State, Tribal, local, or private lands 
that are not federally funded, authorized, or permitted, do not require 
section 7(a)(2) consultations.
    If a Federal action may affect a listed species or its critical 
habitat, the responsible Federal agency (action agency) must enter into 
consultation with us. As a result of this consultation, we document 
compliance with the requirements of section 7(a)(2) through our 
issuance of:
    (1) A concurrence letter for Federal actions that may affect, but 
are not likely to adversely affect, listed species or critical habitat; 
or
    (2) A biological opinion for Federal actions that may affect, and 
are likely to adversely affect, listed species or critical habitat.
    When we issue a biological opinion concluding that a project is 
likely to jeopardize the continued existence of a listed species or 
destroy or adversely modify critical habitat, we also provide 
reasonable and prudent alternatives to the project, if any are 
identifiable. We define ``reasonable and prudent alternatives'' at 50 
CFR 402.02 as alternative actions identified during consultation that:
    <bullet> Can be implemented in a manner consistent with the 
intended purpose of the action,
    <bullet> Can be implemented consistent with the scope of the 
Federal agency's legal authority and jurisdiction,
    <bullet> Are economically and technologically feasible, and
    <bullet> 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 each species (the Georgia pigtoe, interrupted 
rocksnail, and rough hornsnail).
    Section 4(b)(8) of the Act requires us to briefly evaluate and 
describe, in any proposed or final regulation that designates critical 
habitat, activities involving a Federal action that may destroy or 
adversely modify such habitat, or that may be affected by such 
designation.
    Activities that, when carried out, funded, or authorized by a 
Federal agency, may affect critical habitat and therefore should result 
in consultation for each species (Georgia pigtoe, interrupted 
rocksnail, and rough hornsnail) include, but are not limited to:
    (1) Actions that would alter the geomorphology of their stream and 
river habitats. Such activities could include, but are not limited to, 
instream excavation or dredging, impoundment, channelization, and 
discharge of fill materials. These activities could cause aggradation 
or degradation of the channel bed elevation or significant bank erosion 
and result in entrainment or burial of these mollusks, and could cause 
other direct or cumulative adverse effects to these species and their 
life cycles.
    (2) Actions that would significantly alter the existing flow 
regime. Such activities could include, but are not limited to, 
impoundment, water diversion, water withdrawal, and hydropower 
generation. These activities could eliminate or reduce the habitat 
necessary for growth and reproduction of these mollusks.
    (3) Actions that would significantly alter water chemistry or water 
quality (for example, temperature, pH, contaminants, and excess 
nutrients). Such activities could include, but are not limited to, 
hydropower discharges, or the release of chemicals, biological 
pollutants, or heated effluents into surface water or connected 
groundwater at a point source or by dispersed release (non-point 
source). These activities could alter water conditions that are beyond 
the tolerances of these mollusks and result in direct or cumulative 
adverse affects to the species and their life cycles.
    (4) Actions that would significantly alter stream bed material 
composition and quality by increasing sediment deposition or 
filamentous algal growth. Such activities could include, but are not 
limited to, construction projects, livestock grazing, timber harvest, 
off-road vehicle use, and other watershed and floodplain disturbances 
that release sediments or nutrients into the water. These activities 
could eliminate or reduce habitats necessary for the growth and 
reproduction of these mollusks by causing excessive sedimentation and 
burial of the species or their habitats, or nutrification leading to 
excessive filamentous algal growth. Excessive filamentous algal growth 
can cause reduced nighttime dissolved oxygen levels through 
respiration, cover the hard substrates required by aquatic snails for 
egg deposition, and prevent mussel glochidia from settling into stream 
sediments.

Exemptions and Exclusion

Application of Section 4(a)(3) of the Act
    The Sikes Act Improvement Act of 1997 (Sikes Act) (16 U.S.C. 670a) 
required each military installation that includes land and water 
suitable for the conservation and management of

[[Page 31133]]

natural resources to complete an integrated natural resources 
management plan (INRMP) by November 17, 2001. An INRMP integrates 
implementation of the military mission of the installation with 
stewardship of the natural resources found on the base. Among other 
things, each INRMP must, to the extent appropriate and applicable, 
provide for fish and wildlife management; fish and wildlife habitat 
enhancement or modification; wetland protection, enhancement, and 
restoration where necessary to support fish and wildlife; and 
enforcement of applicable natural resource laws.
    The National Defense Authorization Act for Fiscal Year 2004 (Pub. 
L. 108-136) amended the Act to limit areas eligible for designation as 
critical habitat. Specifically, section 4(a)(3)(B)(i) of the Act (16 
U.S.C. 1533(a)(3)(B)(i)) now provides: ``The Secretary shall not 
designate as critical habitat any lands or other geographical areas 
owned or controlled by the Department of Defense, or designated for its 
use, that are subject to an integrated natural resources management 
plan prepared under section 101 of the Sikes Act (16 U.S.C. 670a), if 
the Secretary determines in writing that such plan provides a benefit 
to the species for which critical habitat is proposed for 
designation.''
    There are no Department of Defense lands with a completed INRMP 
within the proposed critical habitat designation for any of the three 
species.
Application of Section 4(b)(2) of the Act
    Section 4(b)(2) of the Act states that the Secretary must designate 
or make revisions to critical habitat on the basis of the best 
available scientific data after taking into consideration the economic 
impact, national security impact, and any other relevant impact of 
specifying any particular area as critical habitat. The Secretary may 
exclude an area from critical habitat if he determines that the 
benefits of such exclusion outweigh the benefits of specifying such 
area as part of the critical habitat, unless he determines, based on 
the best scientific data available, that the failure to designate such 
area as critical habitat will result in the extinction of the species. 
In making that determination, the legislative history is clear that the 
Secretary has broad discretion regarding which factors to use and how 
much weight to give to any factor.
    Under section 4(b)(2) of the Act, we must consider the economic 
impact, national security impact, and any other relevant impact of 
specifying any particular area as critical habitat. For example, 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 landowners have developed any conservation plans for 
the area, or whether there are conservation partnerships that would be 
encouraged by designation of, or exclusion of lands 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 the economic impacts, environmental impacts, 
and any social impacts that might occur because of the designation.
    This discussion of the potential economic and other impacts of 
critical habitat designation is separate from and has not been 
considered in the proposed listing rule. The inclusion of this 
information in the proposed rule is solely for the purpose of 
soliciting public comments on the proposed critical habitat 
designation, not the proposed listing.
    Under section 4(b)(2) of the Act, in considering whether to exclude 
a particular area from the designation, we must identify the benefits 
of including the area in the designation, identify the benefits of 
excluding the area from the designation, and determine whether the 
benefits of exclusion outweigh the benefits of inclusion. If, based on 
this analysis, we determine that the benefits of exclusion outweigh the 
benefits of inclusion, we can exclude the area only if such exclusion 
would not result in the extinction of the species.
    In preparing this proposed rule, we have determined that the lands 
within the proposed designation of critical habitat for the Georgia 
pigtoe, interrupted rocksnail, and rough hornsnail are not owned or 
managed by the Department of Defense; there are currently no HCPs for 
the Georgia pigtoe, interrupted rocksnail, and rough hornsnail; and the 
proposed designation does not include any tribal lands or trust 
resources. At this time, we have not identified areas for which the 
benefits of exclusion outweigh the benefits of inclusion; therefore, we 
are not identifying any specific proposed exclusions for the 
designation of critical habitat for interrupted rocksnail, rough 
hornsnail, or Georgia pigtoe.

Economics

    Section 4(b)(2) of the Act allows the Secretary to exclude areas 
from critical habitat for economic reasons if the Secretary determines 
that the benefits of such exclusion exceed the benefits of designating 
the area as critical habitat. However, this exclusion cannot occur if 
it will result in the extinction of the species concerned.
    We are evaluating the economic impacts of proposing critical 
habitat for the Georgia pigtoe, interrupted rocksnail, and rough 
hornsnail. We will announce the availability of the draft economic 
analysis as soon as it is completed, at which time we will seek public 
review and comment. At that time, copies of the draft economic analysis 
will be available for downloading from the Internet at the Federal 
eRulemaking Portal: http://www.regulations.gov, or by contacting the 
Mississippi Fish and Wildlife Office directly (see FOR FURTHER 
INFORMATION CONTACT). We may exclude areas from the final rule based on 
the information in the economic analysis.
Available Conservation Measures
    Conservation measures provided to species listed as endangered or 
threatened under the Act include recognition, recovery actions, 
requirements for Federal protection, and prohibitions against certain 
practices. Recognition through listing encourages and results in 
conservation actions by Federal, State, and private agencies; groups; 
and individuals. The Act provides for possible land acquisition and 
cooperation with the States and requires that recovery actions be 
carried out for all listed species. The protection required of Federal 
agencies and the prohibitions against taking and harm are discussed, in 
part, below.
    Section 7(a) of the Act, as amended, requires Federal agencies to 
evaluate their actions with respect to any species that is proposed or 
listed as endangered or threatened and with respect to its critical 
habitat, if any is being designated. Regulations implementing this 
interagency cooperation provision of the Act are codified at 50 CFR 
part 402. Federal agencies are required to confer with us informally on 
any action that is likely to jeopardize the continued existence of a 
proposed species, or result in destruction or adverse modification of 
proposed critical habitat. If a species is listed subsequently, section 
7(a)(2) requires Federal agencies to ensure that activities they 
authorize, fund, or carry out are not likely to jeopardize the 
continued existence of such a 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 must enter into 
formal consultation with the Service.
    Federal activities that may affect the Georgia pigtoe, interrupted 
rocksnail, and rough hornsnail include, but are not

[[Page 31134]]

limited to, the carrying out or the issuance of permits for reservoir 
construction, stream alterations, discharges, wastewater facility 
development, water withdrawal projects, pesticide registration, mining, 
and road and bridge construction. It has been the experience of the 
Service, however, that nearly all section 7 consultations have been 
resolved so that the species have been protected and the project 
objectives have been met.
    Listing the Georgia pigtoe, interrupted rocksnail, and rough 
hornsnail initiates the development and implementation of rangewide 
recovery plans for each species. These plans will bring together 
Federal, State, and local agency efforts for the conservation of these 
species. Recovery plans will establish a framework for agencies to 
coordinate their recovery efforts. The plans will set recovery 
priorities and estimate the costs of the tasks necessary to accomplish 
the priorities. They also will describe the site-specific actions 
necessary to achieve conservation and survival of each species.
    Listing also will require us to review any actions on Federal lands 
and activities under Federal jurisdiction that may affect the three 
species; allow State plans to be developed under section 6 of the Act; 
encourage scientific investigations of efforts to enhance the 
propagation or survival of the species under section 10(a)(1)(A) of the 
Act; and promote habitat conservation plans non-Federal lands and 
activities under section 10(a)(1)(B) of the Act.
    The Act and its implementing regulations found at 50 CFR 17.21 set 
forth a series of general prohibitions and exceptions that apply to all 
endangered wildlife. These prohibitions, in part, make it illegal for 
any person subject to the jurisdiction of the United States to take 
(includes harass, harm, pursue, hunt, shoot, wound, kill, trap, 
capture, or collect, or to attempt any of these), import or export, 
ship in interstate commerce in the course of commercial activity, or 
sell or offer for sale in interstate or foreign commerce any listed 
species. It also is illegal to possess, sell, deliver, carry, 
transport, or ship any wildlife that has been taken illegally. Certain 
exceptions apply to agents of the Service and State conservation 
agencies.
    Permits may be issued to carry out otherwiseprohibited activities 
involving endangered wildlife species under certain circumstances. 
Regulations governing permits are set forth at 50 CFR 17.22 and 17.23. 
Such permits are available for scientific purposes, to enhance the 
propagation or survival of the species, and for incidental take in 
connection with otherwise lawful activities.
    Under the Interagency Cooperative Policy for Endangered Species Act 
Section 9 Prohibitions, published in the Federal Register on July 1, 
1994 (59 FR 34272), we identify to the maximum extent practicable those 
activities that would or would not constitute a violation of section 9 
of the Act if the Georgia pigtoe, interrupted rocksnail, and rough 
hornsnail are listed. The intent of this policy is to increase public 
awareness as to the effects of these proposed listings on future and 
ongoing activities within a species' range. We believe, based on the 
best available information, that the following actions will not result 
in a violation of the provisions of section 9 of the Act, provided 
these actions are carried out in accordance with existing regulations 
and permit requirements:
    (1) Possession, delivery, or movement, including interstate 
transport that does not involve commercial activity, of specimens of 
these species that were legally acquired prior to the addition of these 
three mollusks on the Federal Register of the Federal List of 
Endangered or Threatened Wildlife;
    (2) Discharges into waters supporting the Georgia pigtoe, 
interrupted rocksnail, and rough hornsnail, provided these activities 
are carried out in accordance with existing regulations and permit 
requirements (e.g., activities subject to section 404 of the Clean 
Water Act and discharges regulated under the National Pollutant 
Discharge Elimination System (NPDES));
    (3) Development and construction activities designed and 
implemented under State and local water quality regulations and 
implemented using approved best management practices; and
    (4) Any actions that may affect the Georgia pigtoe, interrupted 
rocksnail, and rough hornsnail that are authorized, funded, or carried 
out by a Federal agency (such as bridge and highway construction, 
pipeline construction, hydropower licensing), when the action is 
conducted in accordance with the consultation requirements for listed 
species under section 7 of the Act.
    Potential activities that we believe will likely be considered a 
violation of section 9 of the Act if these species become listed, 
include, but are not limited to, the following:
    (1) Unauthorized possession, collecting, trapping, capturing, 
killing, harassing, sale, delivery, or movement, including interstate 
and foreign commerce, or harming, or attempting any of these actions, 
of the Georgia pigtoe, interrupted rocksnail, and rough hornsnail;
    (2) Unlawful destruction or alteration of their habitats (such as 
unpermitted instream dredging, impoundment, channelization, or 
discharge of fill material) that impairs essential behaviors, such as 
breeding, feeding, or sheltering, or results in killing or injuring any 
of these species;
    (3) Violation of any discharge or water withdrawal permit that 
results in harm or death to any of these species or that results in 
degradation of their occupied habitat to an extent that essential 
behaviors such as breeding, feeding and sheltering are impaired; and
    (4) Unauthorized discharges or dumping of toxic chemicals or other 
pollutants into waters supporting the Georgia pigtoe, interrupted 
rocksnail, and rough hornsnail that kills or injures these species, or 
otherwise impairs essential life-sustaining requirements, such as 
reproduction, food, or shelter.
    Other activities not identified above will be reviewed on a case-
by-case basis to determine if a violation of section 9 of the Act may 
be likely to result from such activity should these mollusks become 
listed. The Service does not consider these lists to be exhaustive and 
provides them as information to the public.
    If you have questions regarding whether specific activities will 
likely violate the provisions of section 9 of the Act, contact the 
Mississippi Fish and Wildlife Office (see FOR FURTHER INFORMATION 
CONTACT). Requests for copies of regulations regarding listed species 
and inquiries about prohibitions and permits should be addressed to the 
U.S. Fish and Wildlife Service, Ecological Services Division, 1875 
Century Boulevard, Atlanta, GA 30345 (phone 404-679-7313; fax 404-679-
7081).

Peer Review

    In accordance with our joint policy published in the Federal 
Register on July 1, 1994 (59 FR 34270), we will seek the expert 
opinions of at least three appropriate and independent specialists 
regarding this proposed rule. The purpose of such review is to ensure 
that our proposed actions are based on scientifically sound data, 
assumptions, and analyses. We will send copies of this proposed rule to 
these peer reviewers immediately following publication in the Federal 
Register. We will invite these peer reviewers to comment, during the 
public comment period, on the specific assumptions and conclusions 
regarding the proposed listing and designation of critical habitat.

[[Page 31135]]

    We will consider all comments and information received during the 
comment period on this proposed rule during preparation of a final 
rulemaking. Accordingly, the final decision may differ from this 
proposal.

Public Hearings

    The Act provides for one or more public hearings on this proposal, 
if requested. Requests for public hearings must be made in writing 
within 45 days of the publication of this proposal (see DATES and 
ADDRESSES sections). We will schedule public hearings on this proposal, 
if any are requested, and announce the dates, times, and places of 
those hearings in the Federal Register and local newspapers at least 15 
days prior to the first hearing.
    Persons needing reasonable accommodations to attend and participate 
in the public hearings should phone Connie Dickard at 601-321-1121 as 
soon as possible. To allow sufficient time to process requests, please 
call no later than one week before the hearing date. Information 
regarding the proposal is available in alternative formats upon 
request.

Regulatory Planning and Review

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

Regulatory Flexibility Act (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 effects of the rule on small entities (small businesses, 
small organizations, and small government jurisdictions). However, no 
regulatory flexibility analysis is required if the head of the agency 
certifies the rule will not have a significant economic impact on a 
substantial number of small entities. The SBREFA amended the Regulatory 
Flexibility Act (RFA) to require Federal agencies to provide a 
statement of the factual basis for certifying that the rule will not 
have a significant economic impact on a substantial number of small 
entities. We currently have some information available but have not 
evaluated it for the three species. At this time, we lack the economic 
information necessary to provide an adequate factual basis for the 
required RFA finding. This includes information on hydroelectric 
generation, transportation, mining, permitted discharges, as well as 
other economic factors within the Coosa River Basin. We will evaluate 
that information and solicit additional information, if needed, to 
determine potential economic impacts of the critical habitat 
designation.
    Our draft economic analysis will provide updated and more complete 
information to enable us to verify or change this initial finding as to 
the proposed designation of critical habitat for each species. Upon 
completion of the draft economic analysis, we will announce 
availability of the draft economic analysis of the proposed designation 
in the Federal Register and reopen the public comment period for the 
proposed designation. We will include with this announcement, as 
appropriate, an initial regulatory flexibility analysis or a 
certification that the rule will not have a significant economic impact 
on a substantial number of small entities accompanied by the factual 
basis for that determination.

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

    In accordance with the Unfunded Mandates Reform Act (2 U.S.C. 
1501), the Service makes 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, tribal 
governments, or the private sector and includes both ``Federal 
intergovernmental mandates'' and ``Federal private sector mandates.'' 
These terms are defined in 2 U.S.C. 658(5)-(7). ``Federal 
intergovernmental mandate'' includes a regulation that ``would impose 
an enforceable duty upon State, local, or tribal governments'' with two 
exceptions. It excludes ``a condition of Federal assistance.'' It also 
excludes ``a duty arising from participation in a voluntary Federal 
program,'' unless the regulation ``relates to a then-existing Federal 
program under which $500,000,000 or more is provided annually to State, 
local, and tribal governments under entitlement authority,'' if the 
provision would ``increase the stringency of conditions of assistance'' 
or ``place caps upon, or otherwise decrease, the Federal Government's 
responsibility to provide funding,'' and the State, local, or tribal 
governments ``lack authority'' to adjust accordingly. At the time of 
enactment, these entitlement programs were: Medicaid; 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 jeopardize the continued existence of 
the species, or destroy or adversely modify critical habitat under 
section 7. While non-Federal entities that receive Federal funding, 
assistance, or permits, or that otherwise require approval or 
authorization from a Federal agency for an action, may be indirectly 
impacted by the designation of critical habitat, the legally binding 
duty to avoid destruction or adverse modification of critical habitat 
rests squarely on the Federal agency. Furthermore, to the extent that 
non-Federal entities are indirectly impacted because they receive 
Federal assistance or participate in a voluntary Federal aid program, 
the Unfunded Mandates Reform Act would not apply; nor would listing 
these species or designating critical habitat shift the costs of the 
large entitlement programs listed above on to State governments.
    (b) We do not believe that the proposed designation of critical 
habitat for the Georgia pigtoe, interrupted rocksnail, or rough 
hornsnail will significantly or uniquely affect small governments 
because these mollusk species occur primarily in State-owned river 
channels, or in remote privately owned stream channels. As such, a 
Small Government Agency Plan is not

[[Page 31136]]

required. We will, however, further evaluate this issue as we conduct 
our economic analysis and revise this assessment if appropriate.

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 critical habitat for the Georgia pigtoe, interrupted 
rocksnail, and rough hornsnail in a takings implications assessment. 
The takings implications assessment concludes that this designation of 
critical habitat for the Georgia pigtoe, interrupted rocksnail, and 
rough hornsnail does not pose significant takings implications.

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 DOI and Department of Commerce policy, 
we requested information from, and coordinated development of this 
proposed critical habitat designation with, appropriate State resource 
agencies in Alabama, Georgia, and Tennessee. The critical habitat 
designation 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).
    Where State and local governments require approval or authorization 
from a Federal agency for actions that may affect critical habitat, 
consultation under section 7(a)(2) of the Act would be required. While 
non-Federal entities that receive Federal funding, assistance, or 
permits, or that otherwise require approval or authorization from a 
Federal agency for an action, may be indirectly impacted by the 
designation of critical habitat, the legally binding duty to avoid 
destruction or adverse modification of critical habitat rests squarely 
on the Federal agency.

Civil Justice Reform

    In accordance with Executive Order 12988, 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 have proposed designating critical habitat for the 
Georgia pigtoe, interrupted rocksnail, and rough hornsnail in 
accordance with the provisions of the Act. This proposed rule uses 
standard property descriptions and identifies the PCEs within the 
designated areas to assist the public in understanding the habitat 
needs of the Georgia pigtoe, interrupted rocksnail, and rough 
hornsnail.

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.)

    We have determined that environmental assessments and environmental 
impact statements, as defined under the authority of the National 
Environmental Policy Act of 1969, need not be prepared in connection 
with regulations adopted under section 4(a) of the Act. We published a 
notice outlining our reasons for this determination in the Federal 
Register on October 25, 1983 (48 FR 49244).
    Also, it is our position that, outside the jurisdiction of the 
United States Court of Appeals for the Tenth Circuit, we do not need to 
prepare environmental analyses as defined by NEPA (42 U.S.C. 4321 et 
seq.) in connection with designating critical habitat under the Act. We 
published a notice outlining our reasons for this determination in the 
Federal Register on October 25, 1983 (48 FR 49244). This assertion was 
upheld by the Circuit Court of the United States for the Ninth Circuit 
(Douglas County v. Babbitt, 48 F.3d 1495 (9th Cir. 1995), cert. denied 
516 U.S. 1042 (1996)).

Clarity of the Rule

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

Government-to-Government Relationship with Tribes

    In accordance with the President's memorandum of April 29, 1994, 
``Government-to-Government Relations with Native American Tribal 
Governments'' (59 FR 22951), 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. We have determined that 
there are no tribal lands occupied at the time of listing contain the 
features essential for the conservation and no tribal lands that are 
unoccupied areas that are essential for the conservation of the Georgia 
pigtoe, interrupted rocksnail, and rough hornsnail. Therefore, 
designation of critical habitat for the Georgia pigtoe, interrupted 
rocksnail, and rough hornsnail has not been proposed on Tribal lands.

Energy Supply, Distribution, or Use

    On May 18, 2001, the President issued an Executive Order (E.O. 
13211; Actions Concerning Regulations That Significantly Affect Energy 
Supply, Distribution, or Use) on regulations that significantly affect 
energy supply, distribution, and use. E.O. 13211 requires agencies to 
prepare Statements of Energy Effects when undertaking certain actions. 
We do not expect the designation of critical habitat for the Georgia 
pigtoe, interrupted rocksnail, or rough hornsnail to significantly 
affect energy supplies, distribution, or use. Although two of the 
proposed units are below hydropower reservoirs, current and proposed 
operating regimes have been deemed adequate for the species, and 
therefore their operations will not be affected by the proposed listing 
or designation of critical habitat. All other proposed units are remote 
from energy

[[Page 31137]]

supply, distribution, or use activities. Therefore, we have determined 
that this action is not a significant energy action, and no Statement 
of Energy Effects is required. However, we will further evaluate this 
issue as we conduct our economic analysis, and review and revise this 
assessment as warranted.

References Cited

    A complete list of all references cited in this rulemaking is 
available upon request from the Field Supervisor, Mississippi Fish and 
Wildlife Office (see FOR FURTHER INFORMATION CONTACT section).

Author(s)

    The primary author of this package is Paul Hartfield (see FOR 
FURTHER INFORMATION CONTACT section).

List of Subjects in 50 CFR Part 17

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

Proposed Regulation Promulgation

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

PART 17--[AMENDED]

    1. The authority citation for part 17 continues to read as follows:
    Authority: 16 U.S.C. 1361-1407; 16 U.S.C. 1531-1544; 16 U.S.C. 
4201-4245; Pub. L. 99-625, 100 Stat. 3500; unless otherwise noted.
    2. Amend Sec.  17.11(h) as follows:
    a. Add ``Pigtoe, Georgia'' in alphabetical order under ``CLAMS;'' 
and
    b. Add ``Rocksnail, interrupted'' and ``Hornsnail, rough'' in 
alphabetical order under ``SNAILS,'' to the List of Endangered and 
Threatened Wildlife to read as follows:
    Sec.  17.11 Endangered and threatened wildlife.
* * * * *
    (h) * * *

--------------------------------------------------------------------------------------------------------------------------------------------------------
                    Species                                           Vertebrate
------------------------------------------------                   population where                                         Critical
                                                  Historic range     endangered or        Status         When listed        habitat       Special rules
         Common name            Scientific name                       threatened
--------------------------------------------------------------------------------------------------------------------------------------------------------
 * * * * * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------
CLAMS
--------------------------------------------------------------------------------------------------------------------------------------------------------
 * * * * * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------
Pigtoe, Georgia                Pleurobema        U.S.A. (AL, GA,   NA                E                                  17.95(f)         NA
                                hanleyianum       TN)
--------------------------------------------------------------------------------------------------------------------------------------------------------
 * * * * * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------
SNAILS
--------------------------------------------------------------------------------------------------------------------------------------------------------
* * * * * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------
Hornsnail, rough               Pleurocera        U.S.A. (AL)       NA                E                                  17.95(f)         NA
                                foremani
--------------------------------------------------------------------------------------------------------------------------------------------------------
* * * * * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------
Rocksnail, interrupted         Leptoxis          U.S.A. (AL, GA)   NA                E                                  17.95(f)         NA
                                foremani
--------------------------------------------------------------------------------------------------------------------------------------------------------
* * * * * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------

    3. Amend Sec.  17.95(f) by adding entries for ``Georgia pigtoe 
(Pleurobema hanleyianum)'', ``Interrupted Rocksnail (Leptoxis 
foremani)'', and ``Rough Hornsnail (Pleurocera foremani)'' at the end 
of the paragraph to read as set forth below:
    Sec.  17.95 Critical habitat fish and wildlife.
* * * * *
    (f) Clams and Snails.
* * * * *
Georgia Pigtoe (Pleurobema hanleyianum)
    (1) Critical habitat units are depicted for Cherokee, Coosa, and 
Clay Counties, Alabama; Murray and Whitfield Counties, Georgia; and 
Bradley and Polk Counties, Tennessee, on the maps below.
    (2) The primary constituent elements (PCEs) of critical habitat for 
the Georgia pigtoe are the habitat components that provide:
    (i) Geomorphically stable stream and river channels and banks 
(channels that maintain lateral dimensions, longitudinal profiles, and 
sinuosity patterns over time without an aggrading or degrading bed 
elevation).
    (ii) A hydrologic flow regime (the magnitude, frequency, duration, 
and seasonality of discharge over time) necessary to maintain benthic 
habitats where the species are found. Unless other information becomes 
available, existing conditions at locations where the species occur 
will be considered as minimal flow requirements for survival.
    (iii)Water quality (including temperature, pH, hardness, turbidity, 
oxygen content, and chemical constituents) that meets or exceeds the 
current aquatic life criteria established under the Clean Water Act (33 
U.S.C. 1251-1387).
    (iv) Sand, gravel, cobble, boulder, or bedrock substrates with low 
to moderate amounts of fine sediment and attached filamentous algae.
    (v) The presence of fish host(s) for the Georgia pigtoe (species 
currently unknown). Diverse assemblages of native fish will serve as a 
potential indication of presence of host fish.
    (3) Critical habitat does not include manmade structures existing 
on the effective date of this rule and not containing one or more of 
the PCEs, such as buildings, bridges, aqueducts, airports, and roads, 
and the land on which such structures are located.

[[Page 31138]]

    (4) Critical habitat unit maps. Maps were developed from USGS 7.5' 
quadrangles, and critical habitat unit upstream and downstream limits 
were then identified by longitude and latitude using decimal degrees.
    (5) Note: Index map of critical habitat units for the Georgia 
pigtoe follows:
BILLING CODE 4310-55-S
[GRAPHIC] [TIFF OMITTED] TP29JN09.000


[[Page 31139]]


    (6) Unit 1 for Georgia pigtoe (GP 1): Conasauga River, Bradley and 
Polk Counties, Tennessee; Murray and Whitfield Counties, Georgia.
    (i) Unit GP 1 includes the channel of the Conasauga River from the 
confluence of Minnewaga Creek (longitude 84.690540, latitude 
35.003703), Polk County, Tennessee, downstream to U.S. Highway 76 
(longitude 84.873083, latitude 34.783154), Murray/Whitfield County, 
Georgia.
    (ii) Note: Map of Unit 1 (GP 1) for Georgia pigtoe (Conasauga 
River) follows:
[GRAPHIC] [TIFF OMITTED] TP29JN09.001


[[Page 31140]]


    (7) Unit 2 for Georgia pigtoe (GP 2), Terrapin Creek and Coosa 
River, Cherokee County, Alabama.
    (i) Unit GP 2 includes the channel of Terrapin Creek from Alabama 
Highway 9 (longitude 85.612250, latitude 34.062972), downstream to the 
confluence with the Coosa River (longitude 85.687750, latitude 
34.13084), Cherokee County, Alabama; and the Coosa River channel from 
Weiss Dam (longitude 85.753667, latitude 34.172361), downstream to a 
point 1.6 km (1 mi) below the confluence of Terrapin Creek (longitude 
85.701407, latitude 34.123895), Cherokee County, Alabama.
    (ii) Note: Map of Unit 2 (GP 2) for Georgia pigtoe (Terrapin Creek 
and Coosa River) follows:

[[Page 31141]]

[GRAPHIC] [TIFF OMITTED] TP29JN09.002


[[Page 31142]]


    (8) Unit 3 for Georgia pigtoe (GP 3): Hatchet Creek, Coosa and Clay 
Counties, Alabama.
    (i)Unit GP 3 includes the channel of Hatchet Creek from Clay County 
Road 4 (longitude 86.054306, latitude 33.129472), Clay County, 
downstream to the confluence of Swamp Creek at Coosa County Road 29 
(longitude 86.338361, latitude 32.860944), Coosa County, Alabama.
    (ii)Note: Map of Unit 3 (GP 3) for Georgia pigtoe (Hatchet Creek) 
follows:
[GRAPHIC] [TIFF OMITTED] TP29JN09.003


[[Page 31143]]


Interrupted Rocksnail (Leptoxis foremani)
    (1) Critical habitat units are depicted for Cherokee and Elmore 
Counties, Alabama, and Gordon and Floyd Counties, Georgia, on the maps 
below.
    (2) The primary constituent elements (PCEs) of critical habitat for 
the interrupted rocksnail are the habitat components that provide:
    (i) Geomorphically stable stream and river channels and banks 
(channels that maintain lateral dimensions, longitudinal profiles, and 
sinuosity patterns over time without an aggrading or degrading bed 
elevation).
    (ii) A hydrologic flow regime (the magnitude, frequency, duration, 
and seasonality of discharge over time) necessary to maintain benthic 
habitats where the species are found. Unless other information becomes 
available, existing conditions at locations where the species occur 
will be considered as minimal flow requirements for survival.
    (iii) Water quality (including temperature, pH, hardness, 
turbidity, oxygen content, and chemical constituents) that meets or 
exceeds the current aquatic life criteria established under the Clean 
Water Act (33 U.S.C. 1251-1387).
    (iv) Sand, gravel, cobble, boulder, or bedrock substrates with low 
to moderate amounts of fine sediment and attached filamentous algae.
    (3) Critical habitat does not include manmade structures existing 
on the effective date of this rule and not containing one or more of 
the PCEs, such as buildings, bridges, aqueducts, airports, and roads, 
and the land on which such structures are located.
    (4) Critical habitat unit maps. Maps were developed from USGS 7.5' 
quadrangles, and critical habitat unit upstream and downstream limits 
were then identified by longitude and latitude using decimal degrees.
    (5) Note: Index map of critical habitat units for the interrupted 
rocksnail follows:

[[Page 31144]]

[GRAPHIC] [TIFF OMITTED] TP29JN09.004


[[Page 31145]]


    (6) Unit 1 for interrupted rocksnail (IR 1): Coosa River, Cherokee 
County, Alabama.
    (i) Unit IR 1 includes the Coosa River channel from Weiss Dam 
(longitude 85.753667, latitude 34.172361), downstream to a point 1.6 km 
(1 mi) below the confluence of Terrapin Creek (longitude 85.701407, 
latitude 34.123895), Cherokee County, Alabama.
    (ii) Note: Map of Unit 1 (IR 1) for interrupted rocksnail (Coosa 
River) follows:
[GRAPHIC] [TIFF OMITTED] TP29JN09.005


[[Page 31146]]


    (7) Unit 2 for interrupted rocksnail (IR 2): Oostanaula River, 
Gordon and Floyd Counties, Georgia.
    (i) Unit IR 2 includes the primary channel of the Oostanaula River 
from the confluence of the Conasauga and Coosawattee Rivers (longitude 
84.904611, latitude 34.544833), Gordon County, downstream to Georgia 
Highway 1 Loop (longitude 85.171417, latitude 34.260694), Floyd County, 
Georgia.
    (ii) Note: Map of Unit 2 (IR 2) for interrupted rocksnail 
(Oostanaula River) follows:
[GRAPHIC] [TIFF OMITTED] TP29JN09.006


[[Page 31147]]


    (8) Unit 3 for interrupted rocksnail (IR 3): Lower Coosa River, 
Elmore County, Alabama.
    (i) Unit IR 3 includes the Coosa River channel from Jordan Dam 
(longitude 86.254611, latitude 32.618250), downstream to Alabama 
Highway 111 Bridge (longitude 86.208500, latitude 32.535250), Elmore 
County, Alabama.
    (ii) Note: Map of Unit 3 (IR 3) for interrupted rocksnail (Lower 
Coosa River) follows:
[GRAPHIC] [TIFF OMITTED] TP29JN09.007


[[Page 31148]]


Rough Hornsnail (Pleurocera foremani)
    (1) Critical habitat units are depicted for Elmore and Shelby 
Counties, Alabama, on the maps below.
    (2) The primary constituent elements (PCEs) of critical habitat for 
the rough hornsnail are the habitat components that provide:
    (i) Geomorphically stable stream and river channels and banks 
(channels that maintain lateral dimensions, longitudinal profiles, and 
sinuosity patterns over time without an aggrading or degrading bed 
elevation).
    (ii) A hydrologic flow regime (the magnitude, frequency, duration, 
and seasonality of discharge over time) necessary to maintain benthic 
habitats where the species are found. Unless other information becomes 
available, existing conditions at locations where the species occur 
will be considered as minimal flow requirements for survival.
    (iii) Water quality (including temperature, pH, hardness, 
turbidity, oxygen content, and chemical constituents) that meets or 
exceeds the current aquatic life criteria established under the Clean 
Water Act (33 U.S.C. 1251-1387).
    (iv) Sand, gravel, cobble, boulder, or bedrock substrates with low 
to moderate amounts of fine sediment and attached filamentous algae.
    (3) Critical habitat does not include manmade structures existing 
on the effective date of this rule and not containing one or more of 
the primary constituent elements, such as buildings, bridges, 
aqueducts, airports, and roads, and the land on which such structures 
are located.
    (4) Critical habitat unit maps. Maps were developed from USGS 7.5' 
quadrangles, and critical habitat unit upstream and downstream limits 
were then identified by longitude and latitude using decimal degrees.
    (5) Note: Index map of critical habitat units for the rough 
hornsnail follows:

[[Page 31149]]

[GRAPHIC] [TIFF OMITTED] TP29JN09.008


[[Page 31150]]


    (6) Unit 1 for rough hornsnail (RH 1): Lower Coosa River, Elmore 
County, Alabama.
    (i) Unit RH 1 includes the Coosa River channel from Jordan Dam 
(longitude 86.254611, latitude 32.618250), downstream to the confluence 
of the Tallapoosa River (longitude 86.265417, latitude 32.515417), 
Elmore County, Alabama.
    (ii) Note: Map of Unit 1 (RH 1) for rough hornsnail (Lower Coosa 
River) follows:
[GRAPHIC] [TIFF OMITTED] TP29JN09.009


[[Page 31151]]


    (7) Unit 2 for rough hornsnail (RH 2): Yellowleaf Creek, Shelby 
County, Alabama.
    (i) Unit RH 2 includes the channel of Yellowleaf Creek from the 
confluence of Morgan Creek (longitude 86.459972, latitude 33.283667), 
downstream to 1.6 km (1 mi) below Alabama Highway 25 (longitude 
86.438583, latitude 33.251306), Shelby County, Alabama.
    (ii) Note: Map of Unit 2 (RH 2) for rough hornsnail (Yellowleaf 
Creek) follows:
[GRAPHIC] [TIFF OMITTED] TP29JN09.010


    Dated: May 27, 2009
Jane Lyder
Deputy Assistant Secretary for Fish and Wildlife and Parks
[FR Doc. E9-15236 Filed 6-26-09; 8:45 am]
BILLING CODE 4310-55-C