[Federal Register: November 2, 2010 (Volume 75, Number 211)]
[Rules and Regulations]
[Page 67511-67550]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr02no10-10]
[[Page 67511]]
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Part III
Department of the Interior
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Fish and Wildlife Service
50 CFR Part 17
Endangered and Threatened Wildlife and Plants; Determination of
Endangered Status for the Georgia Pigtoe Mussel, Interrupted Rocksnail,
and Rough Hornsnail and Designation of Critical Habitat; Final Rule
[[Page 67512]]
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DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 17
[Docket No. FWS-R4-ES-2008-0104; MO 92210-0-0008-B2]
RIN 1018-AU88
Endangered and Threatened Wildlife and Plants; Determination of
Endangered Status for the Georgia Pigtoe Mussel, Interrupted Rocksnail,
and Rough Hornsnail and Designation of Critical Habitat
AGENCY: Fish and Wildlife Service, Interior.
ACTION: Final rule.
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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), list the
Georgia pigtoe mussel (Pleurobema hanleyianum), interrupted rocksnail
(Leptoxis foremani), and rough hornsnail (Pleurocera foremani) as
endangered under the Endangered Species Act of 1973, as amended (Act).
We also designate approximately 258 kilometers (km) (160 miles (mi)) of
stream and river channels as critical habitat for the three species, in
Cherokee, Clay, Coosa, Elmore, and Shelby Counties, Alabama; Gordon,
Floyd, Murray, and Whitfield Counties, Georgia; and Bradley and Polk
Counties, Tennessee.
DATES: This rule becomes effective on December 2, 2010.
ADDRESSES: This final rule and final economic analysis are available on
the Internet at http://www.regulations.gov. Comments and materials
received, as well as supporting documentation used in preparing this
final rule are available for public inspection, by appointment, during
normal business hours, at the U.S. Fish and Wildlife Service, Jackson
Ecological Services Field Office, 6578 Dogwood View Parkway, Suite A,
Jackson, MS 39213 (telephone 601-321-1122; facsimile 601-965-4340).
FOR FURTHER INFORMATION CONTACT: Stephen Ricks, Field Supervisor, U.S.
Fish and Wildlife Service, Jackson Ecological Services Field Office
(see ADDRESSES section). If you use a telecommunications device for the
deaf (TDD), call the Federal Information Relay Service (FIRS) at 800-
877-8339.
SUPPLEMENTARY INFORMATION: This document consists of: (1) A final rule
to list as endangered the Georgia pigtoe mussel (Pleurobema
hanleyianum), interrupted rocksnail (Leptoxis foremani), and rough
hornsnail (Pleurocera foremani); and (2) a final rule to designate
critical habitat for each of these three species.
Previous Federal Action
Federal actions for these species prior to June 29, 2009 are
outlined in our proposed rule for these actions (74 FR 31113).
Publication of the proposed rule opened a 60-day comment period, which
closed on August 28, 2009. We reopened the comment period from February
10, 2010, through March 12, 2010, in order to announce the availability
of and receive comments on a draft economic analysis (DEA), and to
extend the comment period on the proposed listing and designation to
accommodate a public hearing (75 FR 6613).
Public Comments
We received comments from the public on the proposed listing action
and proposed critical habitat designation, and, in this rule, we
respond to these issues in a single comments section. Below, we present
the listing analysis first, followed by the analysis for designation of
critical habitat.
Background
It is our intent to discuss only those topics directly relevant to
the listing and designation of critical habitat for the Georgia pigtoe
mussel (Pleurobema hanleyianum), interrupted rocksnail (Leptoxis
foremani), and rough hornsnail (Pleurocera foremani). For information
on our proposed determination, refer to the proposed rule published in
the Federal Register on June 29, 2009 (74 FR 31113).
Georgia Pigtoe Mussel
The Georgia pigtoe (Pleurobema hanleyianum) is a freshwater mussel
in the family Unionidae. It was described in 1852 by Lea as Unio
hanleyianum from the Coosawattee River in Georgia. The species 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 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 hosts
for 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, and 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) in litt.
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 (Gangloff in litt. 2006).
In 1990, the Service initiated a status survey and reviewed 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; 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
nonpoint source pollution, and channel modifications such as
impoundment.
[[Page 67513]]
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 (Hartfield in litt. 2004; 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 ornamented by partial costae (folds in the
surface). The shell is subglobose (not quite spherical); thick, dark
brown to olive in color; occasionally spotted; and generally covered
with fine striae (longitudinal ridges). 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 variant. 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).
In a hatchery setting, mean clutch size for 2-year-old interrupted
rocksnails is around 8.83 (3 to 18 eggs per clutch), and clutch size of
females greater than 3 years is 13.63 (2 to 21 eggs per clutch)
(Johnson in litt. 2009). 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 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 in litt. 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 and 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; 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 (Johnson in litt. 2003, 2004). The cause of
decline was suspected to be some form of water contamination (Johnson
in litt. 2003, 2004; 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 (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,
[[Page 67514]]
and 2 rocksnails in 4 search-hours at another shoal (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 (Pierson in litt. 2005).
During a 40-minute search of this release area in 2006, two interrupted
rocksnails were found (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 a double row 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. In a hatchery setting,
however, the distinctive double row of tubercules do not appear until
the second year of life (5 to 7 mm shell width) (Johnson in litt.
2009).
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, bedrock,
and mud 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
pers. comm. 2006). Although some attempts to induce rough hornsnails to
lay eggs in captivity have been unsuccessful (Sides 2005, p. 27),
others have observed females laying eggs individually or in short
``strips'' (3 to 10 eggs) during late April into July (Johnson in litt.
2009). Cultured rough hornsnails have become reproductively active in
their second year (Johnson in litt. 2009). Some adult individuals
collected from the wild have survived in captivity for 3 years,
suggesting a life span of 4 to 5 years (Garner in litt. 2009, Johnson
in litt. 2009).
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
(Johnson in litt. 2006a). Historical museum records of the rough
hornsnail in the Coosa River (FLMNH in litt. 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 in Calhoun County; Choccolocco and
Peckerwood Creeks in Talladega County; Yellowleaf Creek in Shelby
County; and Yellow Leaf Creek in Chilton County (FLMNH in litt. 2006).
The rough hornsnail is currently known to occur at two locations:
Lower 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 in litt. 2006); however, the species has not
been collected from this shoal reach in recent surveys (Johnson 2002,
pp. 5-9). Yellowleaf Creek is a moderately sized stream where rough
hornsnails were, until recently, only known from about a 50-m (55-yd)
length of the stream. At this location, rough hornsnails occur at
densities of 8 to 32 per m\2\ (1.2 per yd\2\) (Pierson in litt. 2006).
Following publication of the proposed rule (74 FR 31113, June 29,
2009), an intensive survey of Yellowleaf Creek extended the range of
rough hornsnails in this stream to about 1.6 km (1 mi) above and below
the previously known site (Powell in litt. 2009). The Lower Coosa River
is a large river channel where rough hornsnails have recently been
found in two discrete areas (Hartfield pers. obsv. 2001, Crow in litt.
2008). No quantitative estimates have been made at these sites;
however, at one site, rough hornsnail numbers were estimated at 300 to
400 individuals (Crow in litt. 2008). Searches of unimpounded reaches
of the Coosa River and the lower portions of tributaries to the Coosa
River have failed to locate the species elsewhere (Bogan and Pierson
1993a, pp. 1-27; Garner, pers. comm. 2005; Hartfield in litt. 2006).
The two known surviving populations are separated by three impoundments
and about 113 km (70 mi) of unsuitable, impounded channel habitat.
Summary of Comments and Recommendations
During the open comment periods for the proposed rule (74 FR
31113), draft economic analysis, and public hearing (75 FR 6613), we
requested all interested parties submit comments or information
concerning the proposed
[[Page 67515]]
listing and designation of critical habitat for the three mollusks. We
contacted all appropriate State and Federal agencies, county
governments, elected officials, scientific organizations, and other
interested parties and invited them to comment. We also published
newspaper notices inviting public comment in the following newspapers:
Cherokee County Herald, Centre, AL; Daily Home, Talladega, AL; The
Wetumpka Herald, Wetumpka, AL; Chatsworth Times, Chatsworth, GA; Rome
News Tribune, Rome, GA; The Daily Citizen, Dalton, GA; The Calhoun
Times, Calhoun, GA; Cleveland Daily Banner, Cleveland, TN; and Polk
County News, Benton, TN.
We directly notified and requested comments from all affected
States. The State of Alabama provided additional records of one
species. None of the States expressed a position on the actions. During
the comment periods, we received a total of 16 comments from one State
agency, two Federal agencies, eight groups, and three individuals. At
the public hearing, we received three oral comments. A transcript of
the hearing is available for inspection at the Jackson, Mississippi
Ecological Services Field Office (see ADDRESSES section).
Peer Review
In accordance with our peer review policy published in the Federal
Register on July 1, 1994 (59 FR 34270), we requested the expert
opinions of four knowledgeable individuals with expertise on freshwater
mollusks, the Mobile River Basin, and conservation biology principles.
The purpose of such review is to ensure that the designation is based
on scientifically sound data, assumptions, and analyses, including
input of appropriate experts and specialists.
We received written responses from three of the peer reviewers. All
peer reviewers stated that the proposal included a thorough and
accurate review of the available scientific and commercial data on
these mollusks and their habitats. One peer reviewer provided
additional details and minor corrections on the shell descriptions of
the interrupted rocksnail and rough hornsnail. Two reviewers provided
information on clutch size and life span of rough hornsnail. One
reviewer noted the collection of rough hornsnail on mud bottoms, and
recommended including this in the discussion of the physical and
biological features that are essential to the conservation of that
species (primary constituent elements (PCEs)). This information
provided by the reviewers has been incorporated into the appropriate
sections of this final rule. One peer reviewer suggested additional
stream reaches that could be designated as critical habitat for each of
the three species. These suggestions are discussed below.
We reviewed all comments received for substantive issues and new
data regarding the three mollusks, their critical habitats, and the
draft economic analysis. Written comments and oral statements presented
at the public hearing and received during the comment periods are
addressed in the following summary. For readers' convenience, we have
combined similar comments into single comments and responses.
Peer Reviewer Comments
(1) Comment: The Georgia pigtoe survives in only 3 to 5 miles (4.8
to 8 kilometers) of the Conasauga River, and has been extirpated from
more than 99.9 percent of its historic range.
Our response: Over the past 20 years, the Georgia pigtoe has been
collected from two localized collection sites on the Conasauga River,
one at each extreme of a 43-km (27-mi) reach of the river. We have
considered this entire reach as occupied because of the similarity of
habitat within this reach, and the potential of the species to occur
within any portion of the reach.
(2) Comment: Big Canoe, Choccolocco, and Weogufka Creeks should be
designated as critical habitat for Georgia pigtoe.
Our response: While Big Canoe, Choccolocco, and Weogufka Creeks are
within the geographical range of the Georgia pigtoe and appear to be
suitable for the species, we are unaware of any verified historical
records of the species from these three tributaries. Although we have
not included these areas as critical habitat in this final rule, they
are within the geographical range of the species and may prove to be
important in the future to the conservation of the species.
(3) Comment: Choccolocco, Hatchet, and Terrapin Creeks should be
designated as critical habitat for the interrupted rocksnail.
Our response: Choccolocco, Hatchet, and Terrapin Creeks are within
the geographical area historically occupied by the interrupted
rocksnail. Most museum specimens and historical records of interrupted
rocksnail were from the mainstem Coosa River and larger tributaries
(Oostanaula, Coosawhattee, Conasauga, and Etowah Rivers), and we were
able to document records of interrupted rocksnail from the lower reach
of Terrapin Creek. It is also likely that some populations extended
into the lower reaches of some other tributaries. However, this species
requires moderate to high stream flow, and the lower reaches of
Choccolocco and Hatchet Creeks have little flow, due to embayment by
Coosa River reservoirs. As a result, we did not include these areas as
critical habitat in this final rule. Lower Terrapin Creek continues to
experience natural flow, and will be available to colonization if the
species is successfully reintroduced into Unit IR 1.
(4) Comment: Recent sampling has extended the range of the rough
hornsnail in Yellowleaf Creek.
Our response: Following publication of the proposed rule and
closure of the first comment period, a snail survey of lower Yellowleaf
Creek was conducted by biologists from the Service, ADCNR, and Alabama
Power Company. The rough hornsnail was found at several sites within
the upper and lower limits of the proposed critical habitat. The
information that the rough hornsnail currently inhabits all of the area
within Unit RH 2, Yellowleaf Creek, has been incorporated into the
Background and Critical Habitat sections of this final rule.
(5) Comment: Choccolocco Creek, Kelly Creek, and the Coosa River
below Logan Martin Dam in the vicinity of the confluence of Kelly Creek
should be included as critical habitat for the rough hornsnail.
Our response: We identified two areas with greatest conservation
potential for the rough hornsnail, Lower Coosa River (Unit IR 1) and
Yellowleaf Creek (Unit IR 2), as both of these units contain unoccupied
habitat adjacent to occupied areas, with the potential of natural
dispersal and recolonization. Lower Choccolocco Creek was considered to
have minimal conservation potential for the species at this time
because it is embayed by Logan Martin Lake, and is on the Alabama
303(d) list of impaired waters. Kelly Creek, and the short associated
reach of the Coosa River, is remote from currently occupied areas.
Although this area was not included in the critical habitat designation
for rough hornsnail, it may become important for the conservation of
the species at some point in the future.
Comments from States
(6) Comment: There are records of Georgia pigtoe from Kelly, Big
Canoe, and Choccolocco Creeks that were not acknowledged in the
historical distribution.
Our response: It is probable that any large Coosa River tributary
may have supported historical populations of the Georgia pigtoe at some
time in the past. We have relied on published records and museum
specimens to confirm the species' historical presence for purposes
[[Page 67516]]
of this critical habitat designation. Some historical Coosa River
tributary records, however, have been found to be misidentifications of
other closely related species, and we were unable to document any
historical records of Georgia pigtoe from Kelly, Big Canoe, and
Choccolocco Creeks.
Public Comments
(7) Comment: The conclusions supporting the proposed designation of
the critical habitat units are not supported by data or sound science.
The Act requires the Service to refrain from designating critical
habitat when the biological needs of the species are not sufficiently
well known to permit identification of an area as critical habitat
(citing Cape Hatteras Access Preserv. Alliance v. U.S. Dept. Int., 344
F. Supp. 2nd 108, 123 (D.D.C. 2004)).
Our response: We determined that, based on the best available
scientific and commercial data, sufficient information is available to
identify physical and biological features essential to the conservation
of the species and specific areas that meet the definition of critical
habitat (see Primary Constituent Elements (PCEs) section).
In the case cited by the commenter, the Service had not identified
any features essential to the conservation of the species (primary
constituent elements (PCEs)) within some portions of a broad critical
habitat designation for piping plover, but argued that designation was
proper because PCEs would likely be found in the future. The court
found that this was ``beyond the pale of the [Act].'' In contrast, in
both the proposed and this final rule, we identified PCEs within the
designated habitat (see Criteria Used To Identify Critical Habitat, and
Critical Habitat Designation sections). Therefore, we have complied
with the requirements of the Act.
(8) Comment: The Service exceeded the statutory basis for proposing
to designate Units GP2 and IR1 as unoccupied critical habitat by
including the potential for minimum flows as baseline criteria for the
establishment of the units. The Act does not provide for special
management or operational considerations for proposed units that are
presently unoccupied by target species (citing Cape Hatteras Access
Preserv. Alliance v. U.S. Dept. Int., 344 F. Supp. 2nd 108, 123 (D.D.C.
2004)).
Our response: In the case cited by the commenter, the Service
included areas that clearly did not contain PCEs within a broad
critical habitat designation for piping plover. The Court determined
that the Service must show that PCEs, which may in the future require
special consideration or management, are found on the areas it
designated as critical habitat.
In this designation, when considering areas as critical habitat, we
assessed whether the areas contained features that are essential to the
conservation of the species (PCEs) and whether those features may
require special management considerations or protections. The presence
of one or more PCE was documented (see Critical Habitat Designation
section) in all of the stream reaches designated as unoccupied critical
habitat for the Georgia pigtoe, interrupted rocksnail, and rough
hornsnail. We use the language ``* * * one or more * * *'' in
recognition that all areas essential to the conservation of a species
may not contain all PCEs, based on the biology of the species. For
example, a species may require one area for feeding and growing,
another for reproduction or roosting, and still other areas for passage
between feeding and growing areas. So while all areas may not contain
the same constituent elements, they may be important at some life stage
or during some time of the year and collectively they are essential to
the conservation of the species.
Unit GP 2 for the Georgia pigtoe includes the lower reach of
Terrapin Creek, downstream to its confluence with the Coosa River, and
the Coosa River from Weiss Dam downstream to a point below the
confluence of Terrapin Creek in Cherokee County, Alabama (see Critical
Habitat Designation, Unit GP 2, below). All five PCEs identified for
Georgia pigtoe are present in Terrapin Creek and in the Coosa River
portion of Unit GP 2 below the confluence of Terrapin Creek. Unit IR 1
for the interrupted rocksnail includes the Coosa River channel between
Weiss Dam to a point below the confluence of Terrapin Creek (see
Critical Habitat Designation, Unit IR 1, below). All four PCEs
identified for the interrupted rocksnail are present in the Coosa River
portion of the Unit below Terrapin Creek. Two of the five PCEs for
Georgia pigtoe, and two of the four PCEs for interrupted rocksnail, are
currently present in the Coosa River portion of the units between Weiss
Dam and the confluence of Terrapin Creek. Minimum flows are projected
to be released from Weiss Dam as part of a Federal Energy Regulatory
Commission relicensing agreement in the near future that will restore
the remaining PCEs for both of these species in this portion of the
reach, but that was not the sole basis for this designation.
(9) Comment: It is unreasonable to designate unoccupied areas
adjacent to current populations as critical habitat in light of the
Service's lack of knowledge of specific habitat requirements.
Our response: All recent records of the Georgia pigtoe, interrupted
rocksnail, and rough hornsnail are extremely localized. Because rare
aquatic snails and mussels can be difficult to locate, 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. We then considered the
adequacy of occupied habitat for conservation of the species, and
determined that designating only occupied habitat would not be
sufficient to conserve each of these species (see Criteria Used To
Identify Critical Habitat section). For identification of unoccupied
areas essential to the conservation of the species, we established six
criteria for their consideration (see Stream Reaches Not Currently
Occupied section), including the presence of PCEs. One of these
criteria prioritized stream reaches adjacent to currently occupied
areas. These reaches are similar in stream size, geology, and water
quality to adjacent occupied areas, and we believe that it is
reasonable and cost effective to protect areas available for natural
dispersal and reoccupation.
(10) Comment: Critical habitat designation of currently uninhabited
areas remote from occupied areas (Units GP 2, GP 3, IR 1, IR 3) is not
supported by the record, and would be arbitrary and capricious because
there is no analysis, data, or discussion whether released, captive-
bred stock can become self-sustaining.
Our response: Many endangered aquatic mollusks are so rare that
relocations are not an option (National Native Mussel Conservation
Committee 1997, p. 8). However, freshwater mussels, including
endangered and threatened species, have been relocated with some
success from areas of disturbance into new habitats (Cope and Waller
1995, p. 147; U.S. Fish and Wildlife Service 2004, p. 4). Attempts to
relocate imperiled mollusks from areas of natural abundance into
historical habitats have also been successful (e.g., Ahlstedt 1991, p.
141). Aquatic mollusk hatchery husbandry is a relatively new science.
However, much progress has been made over the past 2 decades and
hatchery propagation of aquatic mollusks is now a viable conservation
tool (e.g., Freshwater Mollusk Conservation Society 2006, p. 1-13).
Reintroduction with hatchery propagules is recognized as a primary
recovery task for rare aquatic species in the Mobile River Basin
Aquatic
[[Page 67517]]
Ecosystem Recovery Plan (U.S. Fish and Wildlife Service 2000, p. 30).
As noted in the Background, above, the interrupted rocksnail has been
successfully propagated and produced in sufficient numbers for limited
releases. Another closely related snail, the plicate rocksnail, has
been propagated, and attempts to reintroduce the species into
historical habitat in Alabama have shown success in terms of survival
and natural recruitment in the reintroduced population (Johnson in
litt. 2008). The available information indicates that the Georgia
pigtoe and interrupted rocksnail cannot be conserved without extending
the species' range into historically occupied areas (see Criteria Used
To Identify Critical Habitat section). Reintroduction using hatchery
reared offspring is currently the only option to achieve this
conservation benchmark.
(11) Comment: The Act and its application in designating critical
habitat is unconstitutional in light of the clear limitations on the
use of Federal power in the property clause of the Constitution's Fifth
Amendment (``* * * private property [shall not] be taken for public
use, without just compensation'').
Our response: The designation of critical habitat, in and of
itself, has no legal effect on property rights or constitute a physical
or regulatory ``taking'' of real estate property. Critical habitat does
not preclude property use; rather, it only affects Federal
authorization or funding of projects that may adversely modify critical
habitat. In the event such a finding is made in a section 7
consultation with the Federal funding or authorizing agency, the
Service is required to identify reasonable and prudent project
alternatives. Exemption procedures under the Act provide sufficient
opportunity to accomplish the Service's statutory mandates without
precluding compatible use of private property. Therefore, critical
habitat designation, by itself, does not affect a taking of private
property.
(12) Comment: FWS should conduct an analysis under the National
Environmental Policy Act (NEPA) (42 U.S.C. 4321 et seq.) prior to
listing and designating critical habitat.
Our response: Environmental assessments and environmental impact
statements, as defined under NEPA, are not required for regulations
enacted under section 4 of the Act (see 48 FR 49244, October 25, 1983).
The FWS has determined that, outside of the jurisdiction of the United
States Court of Appeals for the Tenth Circuit, a NEPA analysis is not
required for critical habitat designation.
(13) Comment: Interrupted rocksnails in Alabama (Unit IR 3) that
are covered by the proposal are not wild, naturally occurring species.
The reintroduced colony is not reproducing and is not viable.
Our response: Any interrupted rocksnails currently surviving in
Unit IR 3 are surviving individuals from releases made by ADCNR in 2003
through 2005, or their offspring. While there is currently no evidence
that natural recruitment of rocksnails has occurred on the shoal since
the release, we are unable to confirm their extirpation from the site.
Including this single shoal in the designation alerts Federal action
agencies to the species' potential presence.
(14) Comment: The determination that reintroduction of interrupted
rocksnail into Units IR 1 and IR 3 is essential to its conservation is
not supported by the record and is arbitrary and capricious.
Our response: Under the Summary of Factors Affecting the Species
section, below, we note that the surviving populations of each species
are small, extremely localized, isolated, and vulnerable to habitat
modification, toxic spills, progressive degradation from land surface
runoff, and catastrophic changes to their habitats from flood scour and
drought. Under the Criteria Used To Identify Critical Habitat section,
we discuss areas currently occupied by the species, the species'
limited extent, their vulnerability to random events, and the inability
of these species to naturally recolonize historically occupied areas
that might now support them. This information was used to determine
that the designation of unoccupied critical habitat is essential to the
conservation of the species. Also under the Criteria Used To Identify
Critical Habitat section, we discuss our process for assessing the
potential of historically occupied stream reaches as unoccupied
critical habitat, the criteria we used to determine if they were
essential to the conservation of the species, and the PCEs currently
present in each stream reach considered for designation as critical
habitat. Our reasons for designating Units IR 1 and IR 3 as critical
habitat for the interrupted rocksnail are discussed in some detail in
the Critical Habitat sections, below. These include the presence of
PCEs in both units, the presence of species in both units that are
closely related to the interrupted rocksnail and require similar PCEs,
improvements in water quality and quantity over the past 2 decades, and
the potential of these two stream reaches for reoccupation by the
interrupted rocksnail through reintroduction efforts. Based on this
analysis, and our review of the best available scientific information,
all unoccupied stream reaches included in the critical habitat
designations for each of these three species, including Units IR 1 and
IR 3, are essential to their conservation. Units IR 1 and IR 3,
however, are remote and separated by one (Unit IR 1) or more (Unit IR
3) impoundments from the only surviving population of the interrupted
rocksnail in the Oostanaula River. Therefore, conservation of the
interrupted rocksnail will require reintroduction of the species into
Unit IR 1, and appropriate areas in Unit IR 3.
(15) Comment: Smaller and more protected tributaries should be
considered for reintroductions of the interrupted rocksnail.
Our response: While smaller and more protected tributaries are
within the historical geographical range of the interrupted rocksnail,
and may become important to its conservation, we relied on documented
historically occupied areas for the purposes of preparing this critical
habitat designation for the reasons discussed above (see our response
to Comment 6, above).
(16) Comment: There are no rough hornsnails in the habitat proposed
to be designated as critical habitat.
Our response: Rough hornsnails were documented from Unit RH 1,
Coosa River above the Fall Line during the 1990s (FLMNH in litt. 2006),
and have most recently been documented from two locations below the
Fall Line (Hartfield in litt. 2001, Crow in litt. 2008). In Unit RH 2,
Yellowleaf Creek, rough hornsnails occur throughout the designated
reach (see Background section).
(17) Comment: The Service appears to be proposing to designate
critical habitat on the chance a particular species might move into it
at some point in the future. What happens to unoccupied critical
habitat if a species does not naturally repopulate the area?
Our response: With appropriate management, we hope to conserve the
Georgia pigtoe, interrupted rocksnail, and rough hornsnail within
currently occupied areas and promote natural dispersal into unoccupied
areas adjacent to occupied reaches. We recognize that there is little
chance of natural dispersal of the Georgia pigtoe and interrupted
rocksnail into the designated unoccupied areas that are remote from
surviving populations due to the presence of multiple dams and large
areas of impounded (and thus unsuitable) channels. However, newly
[[Page 67518]]
developed information and technology are promising for successful
reintroductions of hatchery-reared individuals into these areas.
(18) Comment: What happens to critical habitat if a species becomes
definitively extinct?
Our response: The Act requires us to conduct 5-year reviews on the
status of listed species. If a species is determined to be extinct, it
can be removed from the List of Endangered and Threatened Wildlife
through the formal rulemaking process. If a species is removed from the
List due to extinction, areas that have been designated as critical
habitat for that species will no longer be subject to the section 7
consultation requirements of the Act.
(19) Comment: The Service did not consider whether the reintroduced
population of interrupted rocksnail present in Unit IR 3 should be
designated as experimental under section 10(j) of the Act. Listing and
designating critical habitat for reintroduced species is bad public
policy, and is an attempt to circumvent the purposes of section 10(j)
of the Act.
Our response: Under section 10(j), the Secretary of the Department
of the Interior can designate reintroduced populations established
outside the species' current range, but within its historical range, as
``experimental.'' Based on the best available information, we must
determine whether an experimental population is ``essential'' or
``nonessential'' to the continued existence of the species.
Experimental populations that are essential to the continued existence
of the species are treated as a threatened species, and the Secretary
may promulgate regulations under section 4(d) of the Act. Experimental
populations that are not essential to the continued existence of the
species are treated as species proposed for listing. Section
10(j)(C)(ii) prohibits designation of critical habitat only for
experimental populations that are not essential to the continued
existence of the species.
Within this rule, we reviewed the status of the interrupted
rocksnail, its historical and current range, the threats affecting the
conservation of the species, and the areas available for its
conservation. We used this information to identify Unit IR 3 as an area
essential for the conservation of the interrupted rocksnail, and we are
designating it as critical habitat (see Unit IR3: Lower Coosa River,
Elmore County, Alabama, below).
(20) Comment: The reintroduction of the interrupted rocksnail into
Alabama prior to the proposed listing did not allow for consideration
of the Act's reintroduction provisions, or alert the public to the
Service's consideration of experimental status.
Our response: As noted in our response to Comment 13, above, the
reintroduction of the interrupted rocksnail into the lower Coosa River,
Alabama, was a State action conducted under State regulations. The
public was notified by the State through a press release and
publication of the reintroduction in public media.
(21) Comment: The Service recognizes (in the 2003 draft, Freshwater
Mussels and Snails of the Mobile River Basin: Plan for the Controlled
Propagation, Augmentation, and Reintroduction) that reintroductions of
hatchery mollusk propagules is experimental in nature. Therefore, they
should be designated as experimental populations under section 10(j) of
the Act.
Our response: The 2003 draft plan for controlled propagation was
addressed to scientists, institutions, and agencies contemplating
propagation of mollusks as a management strategy. In 2003, mollusk
propagation was an emerging science and technology. This was the first
propagation plan developed for mollusk species, and sought to alert the
intended audience (i.e., scientists and State and Federal agencies
contemplating propagation of mollusks) of the need for rigorous
documentation and monitoring. The use of the term ``experimental'' in
this document has no direct connection to the term's use under section
10(j) of the Act, where it is a term used to identify reintroduced
populations of listed species outside of their geographical range that
may receive specific exemptions from section 9 of the Act.
(22) Comment: The lack of experimental population designation for
interrupted rocksnails (in IR 3) may cause serious negative impacts to
landowners, businesses, and users of the Coosa River, through limiting
landowners' ability to manage properties and creating uncertainty for
landowners and waterway users.
Our response: Unit IR 3 is occupied by the federally protected
tulotoma snail and fine-lined pocketbook, which are currently subject
to the section 7 consultation provisions, as well as the section 9
prohibitions, of the Act. Apart from limited hydropower flow
modifications to reduce take of tulotoma snail by the Alabama Power
Company, we are unaware of any negative impacts to landowners,
businesses, or users of this reach of the Coosa River due to the
presence of mollusk species currently protected under the Act. It is
not anticipated that this listing and the reintroduction of interrupted
rocksnails will impair legal activities in the unit by landowners and
waterway users.
(23) Comment: The proposed critical habitat designation of
unoccupied habitat for the interrupted rocksnail should be withdrawn.
Our response: We are required by section 4(a) of the Act to
designate critical habitat at the time a species is listed, and to
designate unoccupied areas as critical habitat 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 (see
Critical Habitat section). We determined that Unit IR 1 and unoccupied
portions of Units IR 2 and IR 3 are essential to the conservation of
the interrupted rocksnail (see Criteria Used to Identify Critical
Habitat section).
(24) Comment: The data in the proposed rule relative to released
captive interrupted rocksnails are not consistent with ADCNR records.
The proposed rule states that approximately 7,400 interrupted
rocksnails were released into the Coosa River by the State of Alabama
2003-2005, while information from ADCNR indicates that 10,476
rocksnails were released during this same period.
Our response: The numbers reported in the proposed rule were a
typographical error. Records provided to us by TNARI and the State of
Alabama document the release of 7,513 interrupted rocksnails into the
Coosa River 2003-2005. We intended to state that approximately 7,500
snails were released. TNARI records indicate around 10,476 snails were
produced at its hatchery during 2003-2005. These production numbers may
have been erroneously reported as released snails in a presentation by
Dr. Paul Johnson (Johnson in litt. 2010).
(25) Comment: The Service should develop a programmatic safe harbor
agreement (SHA) to cover future releases of listed aquatic mollusks in
Alabama.
Our response: SHAs have been developed as tools to encourage
private landowners and entities to implement conservation measures that
maintain existing populations, encourage colonization by listed
species, or expand existing populations. Programmatic SHAs have been
developed to envelop multiple landowners under a single agreement,
encouraging cooperative implementation and greatly reducing paperwork.
SHAs and programmatic SHAs can be important conservation tools in
recovering listed species, particularly in situations where the
[[Page 67519]]
cessation of voluntary conservation actions may result in take of
listed species, and return their numbers to a pre-agreement baseline.
We are willing to enter into SHAs, where appropriate, and where they
would result in conservation benefits to the species.
(26) Comment: Due to the lack of specific information on the
biology of these species, the U.S. Army Corps of Engineers (Corps)
could face operational restrictions (at Carters Reservoir) that have no
relation to the conservation of the species.
Our response: Under section 7 of the Act, the Corps will need to
consult with us should their activities adversely affect the species or
adversely modify their critical habitats. We have broadly defined
activities that may destroy or adversely modify critical habitat below
(see Application of the ``Adverse Modification'' Standard, below), and
will work with the Corps to ensure that the best available information
is used when they consult with us. Carters Reservoir is remote from any
of the areas designated as critical habitat by this rule. The
Coosawattee River below Carters Reservoir was designated as critical
habitat for several mussel species in 2004 (see 69 FR 40084, July 1,
2004). Our final economic analysis (Industrial Economics, Inc. 2010,
pp. 3-6--3-10) found that there would only be incremental
administrative costs associated with this listing and critical habitat
designation and operations at Carters Reservoir.
(27) Comment: What is the present need for designation of critical
habitat and its related administrative costs at a time of severe
economic difficulty?
Our response: We are required by the Act to designate critical
habitat, when prudent and determinable, at the time of listing.
However, our economic analysis identified relatively small incremental
costs that will occur due to this critical habitat designation
(Industrial Economics, Inc. 2010). Specifically, incremental costs are
anticipated to result entirely from the added administrative
requirements of forecast section 7 consultations, and are estimated to
be approximately $44,000 annually, assuming a 7 percent discount rate.
These administrative costs are unlikely to have a significant effect on
regional or national economic conditions.
(28) Comment: The Service should avoid interference with barge
transportation in the Alabama-Coosa-Tallapoosa (ACT) River system.
Our response: The critical habitat designations in this rule are
outside of or peripheral to areas used for barge transportation in the
ACT River system. The economic analysis does not anticipate economic
effects to barge transportation in the ACT River system as a result of
this designation.
(29) Comment: Speculation on future environmental flow releases at
Carters Reservoir is pre-decisional, as the Corps' Water Control Manual
update is not complete.
Our response: The economic analysis draws on publically available
information, as well as insights from professionals involved in water
management in the ACT basin, to arrive at reasonable estimates of the
future economic impacts of species conservation efforts on hydropower
and other water management activities. The final economic analysis
includes additional caveats with regard to impacts associated with
potential environmental flow releases related to Corps facilities
(Industrial Economics, Inc. 2010, pp. 3-6--3-10).
(30) Comment: Critical habitat designation could impact power
production, increase costs, and potentially have significant impacts to
municipalities and cooperatives that benefit from hydropower.
Our response: The potential effects of this designation on power
production were considered in the economic analysis. The economic
analysis finds that water managers at four hydroelectric production
facilities in the ACT Basin are likely to undertake conservation
efforts for listed species that will benefit the three mollusks, at an
estimated cost of $8.8 million annually. Specifically, three facilities
(Carters, Weiss, Jordan) are expected to modify operations to provide
additional flows for the benefit of downstream aquatic species.
However, these modifications related to conserving the Georgia pigtoe,
interrupted rocksnail, and rough hornsnail are expected to occur absent
these critical habitat designations, because the areas affected have
been previously designated as critical habitat for, and are occupied
by, other listed mollusk species with similar PCEs and habitat needs.
Incremental economic impacts resulting from these critical habitat
designations are expected to arise from expected administrative
requirements of forecast section 7 consultations between Federal
regulatory agencies and the Service (see our response to Comment 27,
above).
(31) Comment: The listing of the interrupted rocksnail and its
critical habitat could have serious negative impacts on landowners,
businesses, and users of the Coosa River system because it will require
take avoidance and section 7 consultations for an activity that may
affect the population or its critical habitat.
Our response: The Act does not require analysis of the costs of
designating species as endangered or threatened. The potential economic
impacts associated with critical habitat designation for the
interrupted rocksnail, as well as costs of protective measures for the
species already expected to occur without proposed critical habitat
designation, are presented in the economic analysis as baseline costs.
Specifically, incremental costs are anticipated to result entirely from
the added administrative requirements of forecast section 7
consultations, and are estimated to be approximately $44,000 annually,
assuming a 7 percent discount rate. Costs associated with future
conservation efforts that may benefit the three mollusks in critical
habitat areas are estimated to be $8.97 million to $9.16 million
annually, assuming a 7 percent discount rate. Most (96 percent) of
baseline costs quantified are conservation efforts related to potential
lost hydropower production value at three facilities.
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.
The following analysis examines all five factors currently
affecting or that are likely to affect Georgia pigtoe, 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), interrupted rocksnail (Leptoxis
foremani), and rough hornsnail (Pleurocera foremani) 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 section). The Georgia pigtoe has been
eliminated from
[[Page 67520]]
more than 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 its 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 its 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 habitat loss was
compounded by fragmentation and isolation of the remaining free-flowing
portions of the Coosa River and its tributaries, as well as the
species' 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, such as the Georgia
pigtoe, interrupted rocksnail, and rough hornsnail, leaving relict
habitats and populations isolated by the structures as well as by
extensive areas of uninhabitable, impounded waters. 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, including 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). The applicant appealed the
termination order (FERC 2005b, p. 1), but was denied (FERC 2006a, pp.
1-3). However, the applicant has since applied for a preliminary permit
to proceed with the hydroelectric facility and issued a Notice of
Intent and related documents to file for a license application at
Carters Re-Regulation Dam (Fall Line Hydro Company, Inc. 2009).
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 the 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).
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
[[Page 67521]]
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 2 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 (Johnson in litt. 2003, 2004). The cause of
decline is suspected to be some form of water contamination (Johnson in
litt. 2003, 2004; 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 (Neves Pers. comm. 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 (Fusconaia cerina) and triangular kidneyshell
(Ptychobranchus greenii)), and snails (including the endangered
cylindrical lioplax (Lioplax cyclostomaformis)) (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
[[Page 67522]]
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, or rough hornsnail, nor 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, p. 49280), 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 is
not currently considered a threat to the Georgia pigtoe, interrupted
rocksnail, or rough hornsnail. 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 (2010) 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 suggest 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 also suggest 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 Corps), 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 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
[[Page 67523]]
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 of
impaired waters 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 polychlorinated biphenyls
(PCBs) as the reasons for this river reach's inclusion on the list;
nonpoint pollution is identified as the source of pollutants (GDNR
2006, p. 35). Recent studies also implicate 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
determine that inadequate existing regulatory mechanisms are 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 (nonpoint 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 or 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 and 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,
pp. 1-2). 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
preventing 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 increase 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 stage. 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. However, we
have determined that 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.
Conclusion and Determination
We 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.'' We find that each of these three species is
presently in danger of extinction throughout its entire range, based on
the immediacy and magnitude of the threats described above. Based on
our analysis, we have no reason to believe that population trends for
any of the three species addressed in this final rule will improve, nor
will the effects of current threats acting on the species be
ameliorated in the foreseeable future. Therefore, on the basis of the
best available scientific and commercial information, we are listing
the Georgia pigtoe, interrupted rocksnail, and rough hornsnail as
endangered under the Act.
[[Page 67524]]
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.
Summary of Critical Habitat Changes From Proposed Rule
We have considered all comments and information received during the
open comment period for the proposed rule to designate critical habitat
for the Georgia pigtoe mussel, interrupted rocksnail, and rough
hornsnail. We have included mud as a substrate utilized by the rough
hornsnail based upon information provided by a peer reviewer, and added
this descriptor into PCE 4 for the rough hornsnail (see Peer Review,
above, and rough hornsnail PCE 4, below). We have also modified PCE 3
for all three species to reflect information under Factors A and D,
above, that some parameters identified under current water quality life
criteria established under the Clean Water Act (33 U.S.C. 1251-1387)
are not adequate to sustain normal behavior, growth, and viability of
all life stages of mollusks. We have also defined the upstream and
downstream limits of the critical habitat units by Universal Transverse
Mercator (UTM) zone 16, coordinates in the Regulation Promulgation,
below. No other changes have been made to the proposed designation,
including the number, extent, and location of the individual units
designated as critical habitat.
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 geographic area occupied by the species must first have the
physical and biological 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 (i.e., areas on which are
found the Primary Constituent Elements (PCEs), as defined at 50 CFR
424.12(b)). Second, 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.
When determining which areas we should propose 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
Service, are necessary for the recovery of the species. For these
reasons, a critical habitat designation should not be interpreted as
meaning that habitat outside the designated area is unimportant or may
not be required for recovery of the species in question.
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.
Methods
As required by section 4(b)(2) of the Act, we use the best
scientific data available in determining occupied areas
[[Page 67525]]
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 are 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 rule. 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
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 with mud or
silt bottoms 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 are affected by habitat stability, water
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
[[Page 67526]]
(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 endangered and threatened species and their critical
habitats as described in the Memorandum of Agreement that our agencies
signed in 2001 (66 FR 11201, February 22, 2001). Other factors that can
potentially alter water quality are droughts and periods of low flow,
nonpoint 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, p. 85).
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, p. 373). Geomorphic instability can
result in the loss of interstitial habitats and juvenile mussels due to
scouring or deposition (e.g., Hartfield 1993, pp. 132-139). 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, 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 is found. Unless other information becomes
available, existing conditions at locations where the species occurs
will be considered as minimal flow requirements for survival.
(3) Water quality, including temperature, pH, hardness, turbidity,
oxygen content, and chemical characteristics necessary for normal
behavior, growth, and viability of all life stages.
(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 is found. Unless other information becomes
available, existing conditions at locations where the species occurs
will be considered as minimal flow requirements for survival.
(3) Water quality, including temperature, pH, hardness, turbidity,
oxygen content, and chemical characteristics necessary for normal
behavior, growth, and viability of all life stages.
(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 characteristics necessary for normal
behavior, growth, and viability of all life stages.
(4) Sand, gravel, cobble, boulder, bedrock, or mud substrates with
low to moderate amounts of fine sediment and attached filamentous
algae.
This critical habitat designation is designed for the conservation
of the physical and biological features essential to the life-history
functions that were the basis for the determination of endangered
status 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 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.
[[Page 67527]]
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
identified 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 are presently under special management or protection provided
by a legally operative management plan or agreement for the
conservation of the interrupted rocksnail, rough hornsnail, or Georgia
pigtoe. Various activities in or adjacent to each of the critical
habitat units described below 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 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 critical habitat
units include those listed in the Effects of Critical Habitat
Designation section as Federal Activities that may affect critical
habitat and require consultation, below.
Criteria Used To Identify Critical Habitat
We are designating 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 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 identified as 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 Designated 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.
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 is at a high risk of extinction and
highly susceptible to stochastic events.
Unoccupied Stream Reaches Designated as Critical Habitat
The streams not currently occupied that we are designating 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
[[Page 67528]]
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 identified as critical habitat below, boundaries extend from the
nearest downstream landmark at both 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 and Floyd counties,
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. 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, 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,
Yellowleaf Creek and the Lower Coosa River. At the time we proposed
these areas as critical habitat (74 FR 31113) for the rough hornsnail,
we considered only a 3.2-km (2-mi) reach of Yellowleaf Creek, Shelby
County, Alabama, as occupied by the species. A snail survey conducted
by a Service biologist and others (Powell in litt. 2009) has since
found the species throughout the designated area. Therefore, we
consider the entire designated 6.4-km (4-mi) reach of Yellowleaf Creek
as occupied by the rough hornsnail.
Collections during the 1990s from 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 in litt. 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
modified conditions (see Primary Constituent Elements (PCEs) 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 identified 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 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 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 unoccupied critical
habitat units).
Based on the above factors, all unoccupied stream reaches included
in the critical habitat designations for each of these three species
are essential to their conservation.
Georgia Pigtoe
We 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, and 6 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
(2009, p. 22) 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 are designating 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, and 6 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
[[Page 67529]]
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 are
designating the entire reach of Hatchet Creek as critical habitat.
Interrupted Rocksnail
We 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, and 6 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 site 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, and 6 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
interrupted rocksnail. 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, and 6 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 interrupted 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 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 identified 7 km (4 mi) of habitat that is unoccupied by the
rough hornsnail and that meets Criteria 1, 2, 3, and 6 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 (4 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.
Critical Habitat Designation
We are designating three units as critical habitat for the Georgia
pigtoe (GP 1, GP 2, and GP 3), three units for interrupted rocksnail
(IR 1, IR 2, and IR 3), and two units for rough hornsnail (RH 1 and RH
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 units for each species; shows the
occupancy of the units, the approximate extent designated 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 designated units. Critical habitat includes only the
stream channel within the ordinary high water line. In Alabama and
Georgia, the State owns navigable stream bottoms within the ordinary
high water line, and all designated 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 Critical Habitat Units for Georgia
Pigtoe (GP), Interrupted Rocksnail (IR), and Rough Hornsnail (RH)
------------------------------------------------------------------------
Private State
ownership ownership
Unit Location Occupancy river river
kilometers kilometers
(miles) (miles)
------------------------------------------------------------------------
GP 1...... Conasauga River. Occupied........ 5 (3) 47 (29)
GP 2...... Terrapin Creek Unoccupied...... 0 \1\ 35 (22)
and Coosa River.
GP 3...... Hatchet Creek... Unoccupied...... 0 66 (41)
------------------------------------------------------------------------
Total 5 (3) 148 (92)
------------------------------------------------------------------------
IR 1...... Coosa River..... Unoccupied...... 0 \1\ 11 (7)
IR 2...... Oostanaula River Occupied........ 0 12 (7.4)
Unoccupied...... 0 65 (40.6)
[[Page 67530]]
IR 3...... Lower Coosa Occupied........ 0 \2\1 (0.6)
River.
Unoccupied...... 0 \2\ 12
(7.4)
------------------------------------------------------------------------
Total 0 101 (63)
------------------------------------------------------------------------
RH 1...... Lower Coosa Occupied........ 0 \2\ 14 (9)
River.
Unoccupied...... 0 7 (4)
RH 2...... Yellowleaf Creek Occupied........ 0 6.4 (4)
Unoccupied...... 0 0
------------------------------------------------------------------------
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
critical habitat units include the creek and river channels within the
ordinary high water line. For this purpose, we applied the ordinary
high water line definition found at 33 CFR 329.11, which is defined for
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
identified as a critical habitat unit, the upstream and downstream
boundaries are described generally below; more precise estimates are
provided in the Regulation Promulgation section at the end of this
final 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 includes 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 River 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 identified 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 Georgia 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 potential for
stochastic events in the Conasauga River (the only extant population of
Georgia pigtoe), 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
[[Page 67531]]
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), which is 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 implementation of minimum flows. Over the
past few decades, changes in land uses, use of best management
practices for agriculture and forestry activities in the watershed, and
implementation of State water quality standards 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 its presence in this
stream from the stream's 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 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 have designated 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
[[Page 67532]]
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.
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 in litt. 2006), and
more recent records of the hornsnail extending 2 km (1.2 mi) below the
Fall Line (Hartfield pers. obsv. 2001; Crow in litt. 2008), 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 has been found to occupy this entire reach
(Powell in litt. 2009). This reach of Yellowleaf Creek is characterized
by a stable channel, natural flows, and appropriate water quality and
substrates (PCEs 1, 2, 3, and 4). 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;
the potential of significant alteration of water chemistry or water
quality due to discharges or nonpoint source pollution; 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.
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
[[Page 67533]]
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.
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:
Can be implemented in a manner consistent with the
intended purpose of the action,
Can be implemented consistent with the scope of the
Federal agency's legal authority and jurisdiction,
Are economically and technologically feasible, and
Would, in the Director's opinion, avoid jeopardizing the
continued existence of the listed species or destroying or adversely
modifying critical habitat.
Reasonable and prudent alternatives can vary from slight project
modifications to extensive redesign or relocation of the project. Costs
associated with implementing a reasonable and prudent alternative are
similarly variable.
Regulations at 50 CFR 402.16 require Federal agencies to reinitiate
consultation on previously reviewed actions in instances where we have
listed a new species or subsequently designated critical habitat that
may be affected and the Federal agency has retained discretionary
involvement or control over the action (or the agency's discretionary
involvement or control is authorized by law). Consequently, Federal
agencies may sometimes need to request reinitiation of consultation
with us on actions for which formal consultation has been completed, if
those actions with discretionary involvement or control may affect
subsequently listed species or designated critical habitat.
Application of the ``Adverse Modification'' Standard
The key factor related to the adverse modification determination is
whether, with implementation of the proposed Federal action, the
affected critical habitat would continue to serve its intended
conservation role for the species, or would retain its current ability
for the PCEs to be functionally established. Activities that may
destroy or adversely modify critical habitat are those that alter the
PCEs to an extent that appreciably reduces the conservation value of
critical habitat for 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 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 (nonpoint
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
[[Page 67534]]
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 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 critical habitat designation for any of the three species.
Therefore, there are no specific lands that meet the criteria for being
exempted from the designation of critical habitat under section 4(a)(3)
of the Act.
Application of Section 4(b)(2) of the Act
Section 4(b)(2) of the Act states that the Secretary must designate
or revise critical habitat on the basis of the best available
scientific data after taking into consideration the economic impact,
national security impact, and any other relevant impact of specifying
any particular area as critical habitat. The Secretary may exclude an
area from critical habitat if he determines that the benefits of such
exclusion outweigh the benefits of specifying such area as part of the
critical habitat, unless he determines, based on the best scientific
data available, that the failure to designate such area as critical
habitat will result in the extinction of the species. In making that
determination, the legislative history is clear that the Secretary has
broad discretion regarding which 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.
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 the proposed rule, we requested information on 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.
In this instance, we have examined all comments submitted with respect
to providing adequate protection and management for the Georgia pigtoe,
interrupted rocksnail, and rough hornsnail. None of the comments
provided sufficient information to satisfy the criteria necessary for
exclusion from final critical habitat.
In preparing this final rule, we determined that the lands within
the 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 conservation partnerships
for the Georgia pigtoe, interrupted rocksnail, and rough hornsnail; and
the designation does not include any tribal lands or trust resources.
Since the critical habitat designation includes only aquatic areas that
are generally held in public trust, involves no Tribal lands, and
includes no areas presently under special management or protection
provided by a legally operative plan or agreement for the conservation
of these mussels, we believe that, other than economics, there are no
other relevant impacts to evaluate under section 4(b)(2).
Economic Analysis (EA)
We prepared an economic analysis that is consistent with the ruling
of the United States Court of Appeals for the Tenth Circuit in New
Mexico Cattle Growers Ass'n v. United States Fish and Wildlife Service,
248 F.3d 1277 (2001), and that was available for public review and
comment during the comment period for the proposed rule. The final
economic analysis is available on the Internet at http://
www.regulations.gov. The final EA (Industrial Economics 2009) considers
the potential economic effects of actions relating to the conservation
of the Georgia pigtoe, interrupted rocksnail, and rough hornsnail,
including costs associated with sections 4, 7, and 10 of the Act, and
including those attributable to designating critical habitat. It
further considers the economic effects of protective measures taken as
a result of other Federal, State, and local laws that aid habitat
conservation for the Georgia pigtoe, interrupted rocksnail, and rough
hornsnail in essential habitat areas. The EA considers both economic
efficiency and distributional effects. In the case of habitat
conservation, efficiency effects generally reflect the ``opportunity
costs'' associated with the commitment of resources to comply with
habitat protection measures (for example, lost economic opportunities
associated with restrictions on land use).
The final economic analysis states that costs associated with
future conservation efforts that may benefit the three mollusks in
critical habitat areas are estimated to be $8.97 million to $9.16
million annually, assuming a 7 percent discount rate. Most (96 percent)
of baseline costs quantified in this analysis are conservation efforts
related to lost hydropower production value at
[[Page 67535]]
three facilities. The remaining 4 percent of potential future baseline
costs are related to transportation activities, water quality
management activities, and National Forest management activities.
However, extensive actions are already currently planned within
most of the critical habitat areas designated for these three species,
on behalf of 11 other listed mollusk species for which the areas have
been previously designated as critical habitat (69 FR 40083, July 1,
2004). Only 5 river miles (8 river kilometers) of this critical habitat
designation do not overlap habitat for the 11 mussels, and no known
projects are planned within, or which may affect, critical habitat in
those areas. As such, incremental costs are anticipated to result
entirely from the added administrative requirements of forecast section
7 consultations, and are estimated to be approximately $44,000
annually, assuming a 7 percent discount rate.
Based on the best available information, including the prepared
economic analysis, we believe that all of the eight units are essential
for the conservation of these species. Critical habitat aids in the
conservation of the species specifically by protecting the primary
constituent elements on which the species depends. It can also result
in benefits by providing information to the public, local and State
governments, Federal agencies, 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. We conclude that these benefits
of inclusion outweigh the above-described costs of designation for all
areas we are designating as critical habitat in this rule.
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. 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 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 otherwise prohibited 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 when 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 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 to 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) Agricultural and silvicultural activites or development and
construction activities designed and
[[Page 67536]]
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, 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. 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
Jackson, Ecological Services Field Office (see ADDRESSES). 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).
Required Determinations
Regulatory Planning and Review--Executive Order 12866
The Office of Management and Budget (OMB) has determined that this
rule is not significant under Executive Order 12866 (E.O. 12866). OMB
bases its determination upon the following four criteria:
(a) Whether the rule will have an annual effect of $100 million or
more on the economy or adversely affect an economic sector,
productivity, jobs, the environment, or other units of the government.
(b) Whether the rule will create inconsistencies with other Federal
agencies' actions.
(c) Whether the rule will materially affect entitlements, grants,
user fees, loan programs, or the rights and obligations of their
recipients.
(d) Whether the rule raises novel legal or policy issues.
Regulatory Flexibility Act (5 U.S.C. 601 et seq.)
Under the Regulatory Flexibility Act (RFA; 5 U.S.C. 601 et seq.),
as amended by the Small Business Regulatory Enforcement Fairness Act
(SBREFA), whenever an agency must publish a notice of rulemaking for
any proposed or final rule, it must prepare and make available for
public comment a regulatory flexibility analysis that describes the
effect of the rule on small entities (i.e., small businesses, small
organizations, and small government jurisdictions). However, no
regulatory flexibility analysis is required if the head of an agency
certifies the rule will not have a significant economic impact on a
substantial number of small entities. SBREFA amended RFA to require
Federal agencies to provide a certification statement of factual basis
for certifying that the rule will not have a significant economic
impact on a substantial number of small entities. In this final rule,
we are certifying that the critical habitat designation for the three
mollusks will not have a significant economic impact on a substantial
number of small entities. The following discussion explains our
rationale.
According to the Small Business Administration (SBA), small
entities include small organizations, such as independent nonprofit
organizations; small governmental jurisdictions, including school
boards and city and town governments that serve fewer than 50,000
residents; as well as small businesses. Small businesses include
manufacturing and mining concerns with fewer than 500 employees,
wholesale trade entities with fewer than 100 employees, retail and
service businesses with less than $5 million in annual sales, general
and heavy construction businesses with less than $27.5 million in
annual business, special trade contractors doing less than $11.5
million in annual business, and agricultural businesses with annual
sales less than $750,000. To determine if potential economic impacts to
these small entities are significant, we consider the types of
activities that might trigger regulatory impacts under this rule, as
well as the types of project modifications that may result. In general,
the term ``significant economic impact'' is meant to apply to a typical
small business firm's business operations.
To determine if the rule could significantly affect a substantial
number of small entities, we consider the number of small entities
affected within particular types of economic activities (e.g., housing
development, grazing, oil and gas production, timber harvesting). We
apply the ``substantial number'' test individually to each industry to
determine if certification is appropriate. However, the SBREFA does not
explicitly define ``substantial number'' or ``significant economic
impact.'' Consequently, to assess whether a ``substantial number'' of
small entities is affected by this designation, this analysis considers
the relative number of small entities likely to be impacted in an area.
In some circumstances, especially with critical habitat designations of
limited extent, we may aggregate across all industries and consider
whether the total number of small entities affected is substantial. In
estimating the number of small entities potentially affected, we also
consider whether their activities have any Federal involvement.
Designation of critical habitat only affects activities authorized,
funded, or carried out by Federal agencies. Some kinds of activities
are unlikely to have any Federal involvement and so will not be
affected by critical habitat designation. In areas where the species
are present, Federal agencies already are required to consult with us
under section 7 of the Act on activities they authorize, fund, or carry
out that may affect the three mollusks. Federal agencies also must
consult with us if their activities may affect critical habitat.
Designation of critical habitat, therefore, could result in an
additional economic impact on small entities due to the requirement to
reinitiate consultation for ongoing Federal
[[Page 67537]]
activities (see Application of the ``Adverse Modification'' Standard
section).
In our final economic analysis of the proposed critical habitat
designation, we evaluated the potential economic effects on small
business entities resulting from conservation actions related to the
listing of the three mollusks and the proposed designation of critical
habitat. The analysis is based on the estimated impacts associated with
the proposed rulemaking as described in Sections 2 through 6 and
Appendix B of the analysis and evaluates the potential for economic
impacts related to: (1) Water management; (2) water quality; and (3)
other activities (dredging, general construction, bridge construction,
and natural gas pipeline).
According to the final economic analysis, impacts on small entities
due to this rule are expected to be modest because the incremental
costs of the rule are estimated to be administrative in nature. The
only incremental impacts associated with this rulemaking are
administrative costs of consultation under section 7 of the Act, which
are expected to be approximately $44,000 annually, using a 7 percent
discount rate. The average of such costs to a small business over the
next 20 years, discounted at 7 percent, is estimated to range from $0
to $18,300. The annualized incremental impacts, discounted at 7
percent, are expected to be distributed among specific activities as
follows: 42 percent transportation/construction, 33 percent water
quality, 18 percent National Forest activities, and 7 percent water
management.
In summary, we considered whether this designation will result in a
significant economic effect on a substantial number of small entities.
Based on the above reasoning and currently available information, we
concluded that this rule will not result in a significant economic
impact on a substantial number of small entities. Therefore, we are
certifying that the designation of critical habitat for the three
mollusks will not have a significant economic impact on a substantial
number of small entities, and a regulatory flexibility analysis is not
required.
Energy Supply, Distribution, or Use--Executive Order 13211
Pursuant to Executive Order No. 13211, ``Actions Concerning
Regulations that Significantly Affect Energy Supply, Distribution, or
Use,'' issued May 18, 2001, Federal agencies must prepare and submit a
``Statement of Energy Effects'' for all ``significant energy actions.''
The purpose of this requirement is to ensure that all Federal agencies
``appropriately weigh and consider the effects of the Federal
Government's regulations on the supply, distribution, and use of
energy.''
The Office of Management and Budget (OMB) has provided guidance for
implementing E.O. 13211 that outlines nine outcomes that may constitute
``a significant adverse effect'' when compared without the regulatory
action under consideration. The economic analysis finds that
incremental impacts of the designation of critical habitat are the
subject of the analysis under Executive Order No. 13211. The potential
effects of this designation on power production were considered in the
economic analysis. The economic analysis finds that water managers at
four hydroelectric production facilities in the ACT Basin are likely to
undertake conservation efforts for listed species that will benefit the
three mollusks, at an estimated cost of $8.8 million annually.
Specifically, three facilities (Carters, Weiss, Jordan) are expected to
modify operations to provide additional flows for the benefit of
downstream aquatic species. However, these modifications related to
conserving the Georgia pigtoe, interrupted rocksnail, and rough
hornsnail are expected to occur absent these critical habitat
designations, because the areas affected have been previously
designated as critical habitat for, and are occupied by, other listed
mollusk species with similar PCEs and habitat needs. Incremental
impacts incurred from this critical habitat designation are all
expected to be administrative in nature, and the designation of
critical habitat for the Georgia pigtoe, interrupted rocksnail, and
rough hornsnail is not expected to lead to any of the adverse outcomes
specified in the OMB guidance. As such, this final designation of
critical habitat is not expected to significantly affect energy
supplies, distribution, or use, and a Statement of Energy Effects is
not required.
Unfunded Mandates Reform Act (2 U.S.C. 1501 et seq.)
In accordance with the Unfunded Mandates Reform Act (2 U.S.C.
1501), 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 have determined that the designation of critical habitat for
the Georgia pigtoe, interrupted rocksnail, or
[[Page 67538]]
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 required.
Takings
In accordance with Executive Order 12630 (``Government Actions and
Interference with Constitutionally Protected Private Property
Rights''), we have analyzed the potential takings implications of
designating 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--Executive Order 13132
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
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--Executive Order 12988
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 designated critical habitat for the Georgia
pigtoe, interrupted rocksnail, and rough hornsnail in accordance with
the provisions of the Act. This final rule uses standard property
descriptions and identifies the PCEs within the designated areas to
assist the public in understanding the habitat needs of the 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 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)).
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, to work directly with
tribes in developing programs for healthy ecosystems, to acknowledge
that tribal lands are not subject to the same controls as Federal
public lands, to remain sensitive to Indian culture, and to make
information available to tribes. One parcel of land adjacent to Unit
RH-1 is owned by the Poarch Creek Band of Indians, and the Creek Indian
Enterprises, a small entity, runs a small casino on the site. We
contacted the Poarch Creek Band regarding our proposed listing and
critical habitat designation, and the draft economic analysis. As of
the publication date of this rule, we have not received any concerns
from, or been contacted by, the Poarch Creek Band regarding the
designation of critical habitat adjacent to their lands.
References Cited
A complete list of all references cited in this rulemaking is
available on the Internet at http://www.regulations.gov and upon
request from the Field Supervisor, Jackson Ecological Services Field
Office (see ADDRESSES section).
Author(s)
The primary author of this package is Paul Hartfield of the Jackson
Ecological Services Field Office (see ADDRESSES).
List of Subjects in 50 CFR Part 17
Endangered and threatened species, Exports, Imports, Reporting and
recordkeeping requirements, Transportation.
Regulation Promulgation
0
Accordingly, we amend part 17, subchapter B of chapter I, title 50 of
the Code of Federal Regulations, as set forth below:
PART 17--[AMENDED]
0
1. The authority citation for part 17 continues to read as follows:
Authority: 16 U.S.C. 1361-1407; 16 U.S.C. 1531-1544; 16 U.S.C.
4201-4245; Pub. L. 99-625, 100 Stat. 3500; unless otherwise noted.
0
2. Amend Sec. 17.11(h) as follows:
0
a. Add ``Pigtoe, Georgia'' in alphabetical order under CLAMS; and
0
b. Add ``Hornsnail, rough'' and ``Rocksnail, interrupted'' in
alphabetical order under SNAILS, to the List of Endangered and
Threatened Wildlife to read as follows:
[[Page 67539]]
Sec. 17.11 Endangered and threatened wildlife.
* * * * *
(h) * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------
Species Vertebrate
------------------------------------------------------------ population
where Critical Special
Historic range endangered Status When listed habitat rules
Common name Scientific name or
threatened
--------------------------------------------------------------------------------------------------------------------------------------------------------
* * * * * * *
Clams
* * * * * * *
Pigtoe, Georgia.................... Pleurobema hanleyianum U.S.A. (AL, GA, TN).. NA E 777 17.95(f) NA
* * * * * * *
Snails
* * * * * * *
Hornsnail, rough................... Pleurocera foremani... U.S.A. (AL).......... NA E 777 17.95(f) NA
* * * * * * *
Rocksnail, interrupted............. Leptoxis foremani..... U.S.A. (AL, GA)...... NA E 777 17.95(f) NA
* * * * * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------
0
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 is found. Unless other information becomes
available, existing conditions at locations where the species occurs
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.
(4) Critical habitat unit maps. Maps were developed from USGS 7.5'
quadrangles. Critical habitat unit upstream and downstream limits were
then identified by longitude and latitude using decimal degrees and
converted to Universal Transverse Mercator (UTM) zone 16, coordinates.
(5) Note: Index map of critical habitat units for the Georgia
pigtoe follows:
[[Page 67540]]
[GRAPHIC] [TIFF OMITTED] TR02NO10.000
BILLING CODE 4310-55-P
(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 (710752.23E, 3875891.03N), Polk County,
Tennessee, downstream to U.S. Highway 76 (694611.06E, 3851057.36N),
Murray/Whitfield County, Georgia.
(ii) Note: Map of Unit 1 (GP 1) for Georgia pigtoe (Conasauga
River) follows:
[[Page 67541]]
[GRAPHIC] [TIFF OMITTED] TR02NO10.001
(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 (628065.76E, 3770007.078N), downstream to the confluence with
the Coosa River (621001.27E, 3777441.03N), Cherokee County, Alabama;
and the Coosa River channel from Weiss Dam (614866.54E, 3781969.16N),
downstream to a point 1.6 km (1 mi) below the confluence of Terrapin
Creek (619751.69E, 3776654.79N), Cherokee County, Alabama.
(ii) Note: Map of Unit 2 (GP 2) for Georgia pigtoe (Terrapin Creek,
Coosa River) follows:
[[Page 67542]]
[GRAPHIC] [TIFF OMITTED] TR02NO10.002
(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 (588215.16E, 3666038.46N), Clay County, downstream to the
confluence of Swamp Creek at Coosa County Road 29 (561904.90E,
3636065.37N), Coosa County, Alabama.
(ii) Note: Map of Unit 3 (GP 3) for Georgia pigtoe (Hatchet Creek)
follows:
[[Page 67543]]
[GRAPHIC] [TIFF OMITTED] TR02NO10.003
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 is found. Unless other information becomes
available, existing conditions at locations where the species occurs
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. Critical habitat unit upstream and downstream limits were
then identified by longitude and latitude using decimal degrees and
converted to Universal Transverse Mercator (UTM) zone 16, coordinates.
(5) Note: Index map of critical habitat units for the interrupted
rocksnail follows:
[[Page 67544]]
[GRAPHIC] [TIFF OMITTED] TR02NO10.004
(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
(614866.53E, 3781969.15N), downstream to a point 1.6 km (1 mi) below
the confluence of Terrapin Creek (619751.694E, 3776654.79N), Cherokee
County, Alabama.
(ii) Note: Map of Unit 1 (IR 1) for interrupted rocksnail (Coosa
River) follows:
[[Page 67545]]
[GRAPHIC] [TIFF OMITTED] TR02NO10.005
BILLING CODE 4310-55-C
(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
(692275.90E, 3824562.96N), Gordon County, downstream to Georgia Highway
1 Loop (668358.62E, 3792574.63N), Floyd County, Georgia.
(ii) Note: Map of Unit 2 (IR 2) for interrupted rocksnail
(Oostanaula River) follows:
[[Page 67546]]
[GRAPHIC] [TIFF OMITTED] TR02NO10.006
BILLING CODE 4310-55-P
(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
(569930.28E, 3609212.67N), downstream to Alabama Highway 111 Bridge
(574324.83E, 3600042.81N), Elmore County, Alabama.
(ii) Note: Map of Unit 3 (IR 3) for interrupted rocksnail (Lower
Coosa River) follows:
[[Page 67547]]
[GRAPHIC] [TIFF OMITTED] TR02NO10.007
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 is found. Unless other information becomes
available, existing conditions at locations where the species occurs
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, bedrock, or mud 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. Critical habitat unit upstream and downstream limits were
then identified by longitude and latitude using decimal degrees and
converted to Universal Transverse Mercator (UTM) zone 16, coordinates.
(5) Note: Index map of critical habitat units for the rough
hornsnail follows:
[[Page 67548]]
[GRAPHIC] [TIFF OMITTED] TR02NO10.008
(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
(569930.28E, 3609212.67N), downstream to the confluence of the
Tallapoosa River (568995.14E, 3597805.93N), Elmore County, Alabama.
(ii) Note: Map of Unit 1 (RH 1) for rough hornsnail (Coosa River)
follows:
[[Page 67549]]
[GRAPHIC] [TIFF OMITTED] TR02NO10.009
(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 (550285.41E, 3682865.13N), downstream to 1.6
km (1 mi) below Alabama Highway 25 (552296.38E, 3679287.87N), Shelby
County, Alabama.
(ii) Note: Map of Unit 2 (RH 2) for rough hornsnail (Yellowleaf
Creek) follows:
[[Page 67550]]
[GRAPHIC] [TIFF OMITTED] TR02NO10.010
* * * * *
Authority: The authority for this section is section 4 of the
Endangered Species Act of 1973, as amended (16 U.S.C. 1531 et seq.).
Dated: October 15, 2010.
Thomas L. Strickland,
Assistant Secretary for Fish and Wildlife and Parks.
[FR Doc. 2010-27417 Filed 11-1-10; 8:45 am]
BILLING CODE 4310-55-C