Endangered and Threatened Wildlife and Plants; Endangered Status for the Alabama Pearlshell, Round Ebonyshell, Southern Sandshell, Southern Kidneyshell, and Choctaw Bean, and Threatened Status for the Tapered Pigtoe, Narrow Pigtoe, and Fuzzy Pigtoe; With Critical Habitat, 61482-61529 [2011-24519]

Agencies

• Fish and Wildlife Service
• DEPARTMENT OF THE INTERIOR

[Federal Register Volume 76, Number 192 (Tuesday, October 4, 2011)]
[Proposed Rules]
[Pages 61482-61529]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-24519]



[[Page 61481]]

Vol. 76

Tuesday,

No. 192

October 4, 2011

Part II





Department of the Interior





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Fish and Wildlife Service





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50 CFR Part 17





 Endangered and Threatened Wildlife and Plants; Endangered Status for 
the Alabama Pearlshell, Round Ebonyshell, Southern Sandshell, Southern 
Kidneyshell, and Choctaw Bean, and Threatened Status for the Tapered 
Pigtoe, Narrow Pigtoe, and Fuzzy Pigtoe; with Critical Habitat; 
Proposed Rule

Federal Register / Vol. 76 , No. 192 / Tuesday, October 4, 2011 / 
Proposed Rules

[[Page 61482]]


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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

[FWS-R4-ES-2011-0050; MO 92210-0-0008-B2]
RIN 1018-AW92


Endangered and Threatened Wildlife and Plants; Endangered Status 
for the Alabama Pearlshell, Round Ebonyshell, Southern Sandshell, 
Southern Kidneyshell, and Choctaw Bean, and Threatened Status for the 
Tapered Pigtoe, Narrow Pigtoe, and Fuzzy Pigtoe; With Critical Habitat

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Proposed rule.

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SUMMARY: We, the U.S. Fish and Wildlife Service, propose to list the 
Alabama pearlshell (Margaritifera marrianae), round ebonyshell 
(Fusconaia rotulata), southern sandshell (Hamiota australis), southern 
kidneyshell (Ptychobranchus jonesi), and Choctaw bean (Villosa 
choctawensis) as endangered, and the tapered pigtoe (Fusconaia burkei), 
narrow pigtoe (Fusconaia escambia), and fuzzy pigtoe (Pleurobema 
strodeanum) as threatened, under the Endangered Species Act of 1973, as 
amended (Act).
    These eight species are endemic to portions of the Escambia River, 
Yellow River, and Choctawhatchee River basins of Alabama and Florida; 
and to localized portions of the Mobile River Basin in Alabama. These 
mussel species have disappeared from other portions of their natural 
ranges primarily due to habitat deterioration and poor water quality as 
a result of excessive sedimentation and environmental contaminants.
    We are also proposing to designate critical habitat under the Act 
for these eight species. In total, approximately 2,406 (kilometers (km) 
(1,495) miles (mi)) of stream and river channels fall within the 
boundaries of the proposed critical habitat designation. The proposed 
critical habitat is located in Bay, Escambia, Holmes, Jackson, 
Okaloosa, Santa Rosa, Walton, and Washington Counties, FL; and Barbour, 
Bullock, Butler, Coffee, Conecuh, Covington, Crenshaw, Dale, Escambia, 
Geneva, Henry, Houston, Monroe, and Pike Counties, Alabama.
    These proposals, if made final, would implement Federal protection 
provided by the Act.

DATES: We will accept comments received or postmarked on or before 
December 5, 2011. We must receive requests for public hearings, in 
writing, at the address shown in the ADDRESSES section by November 18, 
2011.

ADDRESSES: You may submit comments by one of the following methods:
    (1) Electronically: Go to the Federal eRulemaking Portal: https://www.regulations.gov. In the Keyword box, enter Docket No. FWS-R4-ES-
2011-0050, which is the docket number for this rulemaking. Then, in the 
Search panel on the left side of the screen, under the Document Type 
heading, click on the Proposed Rules link to locate this document. You 
may submit a comment by clicking on ``Send a Comment or Submission.''
    (2) By hard copy: Submit by U.S. mail or hand-delivery to: Public 
Comments Processing, Attn: FWS-R4-ES-2011-0050; Division of Policy and 
Directives Management; U.S. Fish and Wildlife Service; 4401 N. Fairfax 
Drive, MS 2042-PDM; Arlington, VA 22203.
    We will not accept e-mail or faxes. We will post all comments on 
https://www.regulations.gov. This generally means that we will post any 
personal information you provide us (see the Public Comments section 
below for more information).

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

SUPPLEMENTARY INFORMATION: This document consists of: (1) A proposed 
rule to list the Alabama pearlshell (Margaritifera marrianae), round 
ebonyshell (Fusconaia rotulata), southern sandshell (Hamiota 
australis), southern kidneyshell (Ptychobranchus jonesi), and Choctaw 
bean (Villosa choctawensis) as endangered, and the tapered pigtoe 
(Fusconaia burkei), narrow pigtoe (Fusconaia escambia), and fuzzy 
pigtoe (Pleurobema strodeanum) as threatened; and (2) proposed critical 
habitat designations for the Alabama pearlshell, round ebonyshell, 
southern sandshell, southern kidneyshell, Choctaw bean, tapered pigtoe, 
narrow pigtoe, and fuzzy pigtoe.

Information Requested

    We intend that any final action resulting from this proposed rule 
will be based on the best scientific and commercial data available and 
be as accurate and as effective as possible. Therefore, we request 
comments or information from the public, other concerned governmental 
agencies, the scientific community, industry, or any other interested 
parties concerning this proposed rule. We particularly seek comments 
concerning:
    (1) Biological, commercial trade, or other relevant data concerning 
any threats (or lack thereof) to these species and regulations that may 
be addressing those threats.
    (2) Additional information concerning the historical and current 
status, range, distribution, and population size of any of these 
species, including the locations of any additional populations.
    (3) Any information on the biological or ecological requirements of 
these species, and ongoing conservation measures for the species and 
their habitat.
    (4) Current or planned activities in the areas occupied by these 
species and possible impacts of these activities on these species.
    (5) The reasons why we should or should not designate habitat as 
``critical habitat'' under section 4 of the Act (16 U.S.C. 1531 et 
seq.) including whether there are threats to these species from human 
activity, the degree of which can be expected to increase due to the 
designation, and whether that increase in threat outweighs the benefit 
of designation such that the designation of critical habitat may not be 
prudent.
    (6) Specific information on:
    (a) The amount and distribution of habitat for these eight mussels;
    (b) What areas, that were occupied at the time of listing (or are 
currently occupied) and that contain features essential to the 
conservation of these species, should be included in the designation 
and why;
    (c) Special management considerations or protection that may be 
needed in critical habitat areas we are proposing, including managing 
for the potential effects of climate change; and
    (d) What areas not occupied at the time of listing are essential 
for the conservation of these species and why.
    (7) Land use designations and current or planned activities in the 
subject areas and their possible impacts on proposed critical habitat.
    (8) Information on the projected and reasonably likely impacts of 
climate change on these species and proposed critical habitat.
    (9) Any probable economic, national security, or other relevant 
impacts of designating any area that may be included in the final 
designation; in particular, any impacts on small entities or families, 
and the benefits of including

[[Page 61483]]

or excluding areas that exhibit these impacts.
    (10) Whether any specific areas we are proposing for critical 
habitat designation should be considered for exclusion under section 
4(b)(2) of the Act, and whether the benefits of potentially excluding 
any specific area outweigh the benefits of including that area under 
section 4(b)(2) of the Act.
    (11) Whether we could improve or modify our approach to designating 
critical habitat in any way to provide for greater public participation 
and understanding, or to better accommodate public concerns and 
comments.
    Please note that submissions merely stating support for or 
opposition to the action under consideration without providing 
supporting information, although noted, will not be considered in 
making a determination, as section 4(b)(1)(A) of the Act directs that 
determinations as to whether any species is a threatened or endangered 
species must be made ``solely on the basis of the best scientific and 
commercial data available.''
    You may submit your comments and materials concerning this proposed 
rule by one of the methods listed in ADDRESSES.
    If you submit information via https://www.regulations.gov, your 
entire submission--including any personal identifying information--will 
be posted on the Web site. If your submission is made via a hardcopy 
that includes personal identifying information, you may request at the 
top of your document that we withhold this information from public 
review. However, we cannot guarantee that we will be able to do so. We 
will post all hardcopy submissions on https://www.regulations.gov. 
Please include sufficient information with your comments to allow us to 
verify any scientific or commercial information you include.
    Comments and materials we receive, as well as supporting 
documentation we used in preparing this proposed rule, will be 
available for public inspection on https://www.regulations.gov, or by 
appointment, during normal business hours, at the U.S. Fish and 
Wildlife Service, Panama City, FL, Fish and Wildlife Office (see FOR 
FURTHER INFORMATION CONTACT).

Previous Federal Actions

    The Alabama pearlshell, round ebonyshell, southern sandshell, 
southern kidneyshell, Choctaw bean, tapered pigtoe, narrow pigtoe, and 
fuzzy pigtoe were first identified as candidates for protection under 
the Act in the May 4, 2004, Federal Register (69 FR 24876). Candidate 
species are assigned Listing Priority Numbers (LPNs) based on immediacy 
and the magnitude of threat, as well as their taxonomic status. The 
lower the LPN, the higher priority that species is for us to determine 
appropriate action using our available resources. In the 2004, 2005 (70 
FR 24870), 2006 (71 FR 53756), 2007 (72 FR 69034), 2008 (73 FR 75176), 
2009 (74 FR 57869), and 2010 (75 FR 69221) Federal Register Candidate 
Notices of Review, the Alabama pearlshell, round ebonyshell, and 
southern kidneyshell were identified as LPN 2 candidate species; the 
narrow pigtoe, southern sandshell, fuzzy pigtoe, and Choctaw bean were 
identified as LPN 5 candidate species; and the tapered pigtoe was 
identified as an LPN 11 candidate species. In our Notices of Review, we 
determined that publication of a proposed rule to list these species 
was precluded by our work on higher priority listing actions. These 
eight species were included in a listing petition filed by the Center 
for Biological Diversity on April 20, 2010. In a separate action, we 
found the petition presented substantial information that the species 
may be warranted for listing. Because we have already made the 
equivalent 12-month finding on these species through our annual 
candidate assessment and notice process, we have also made a 
determination that the species warrant listing. Therefore, we have made 
the requisite findings with regards to the April 20, 2010, petition.

Background

    It is our intent to discuss only those topics directly relevant to 
the listing of the Alabama pearlshell, round ebonyshell, southern 
sandshell, southern kidneyshell, and Choctaw bean as endangered; and 
the tapered pigtoe, narrow pigtoe and fuzzy pigtoe as threatened in 
this section of the proposed rule. For information relevant to the 
designation of critical habitat, see ``Critical Habitat'' section 
below.

Introduction

    North American freshwater mussel fauna is the richest in the world 
and historically numbered around 300 species (Williams et al. 1993, p. 
6). Freshwater mussels are in decline, however, and in the past century 
have become more imperiled than any other group of organisms (Williams 
et al. 2008, p. 55; Natureserve 2011). Approximately 66 percent of 
North America's freshwater mussel species are considered vulnerable to 
extinction or possibly extinct (Williams et al. 1993, p. 6). Within 
North America, the southeastern United States is the hot spot for 
mussel diversity. Seventy-five percent of southeastern mussel species 
are in varying degrees of rarity or possibly extinct (Neves et al. 
1997, pp. 47-51). The central reason for the decline of freshwater 
mussels is the modification and destruction of their habitat, 
especially from sedimentation, dams, and degraded water quality (Neves 
et al. 1997, p. 60; Bogan 1998, p. 376). These eight mussels, like many 
other southeastern mussel species, have undergone reductions in total 
range and population density.
    These eight species are all freshwater bivalve mussels of the 
families Margaritiferidae and Unionidae. The Alabama pearlshell is a 
member of the family Margaritiferidae, while the round ebonyshell, 
southern sandshell, southern kidneyshell, Choctaw bean, tapered pigtoe, 
narrow pigtoe, and fuzzy pigtoe belong to the family Unionidae. These 
mussels are endemic to portions of three Coastal Plain rivers that 
drain south-central and southeastern Alabama and northwestern Florida: 
the Escambia (known as the Escambia River in Florida and the Conecuh 
River in Alabama), the Yellow, and the Choctawhatchee. All three rivers 
originate in Alabama and flow across the Florida panhandle before 
emptying into the Gulf of Mexico, and are entirely contained within the 
East Gulf Coastal Plain Physiographic Region. The Alabama pearlshell is 
also known from three locations in the Mobile River Basin; however, 
only one of those is considered to be currently occupied.

General Biology

    Freshwater mussels generally live embedded in the bottom of rivers, 
streams, and other bodies of water. They siphon water into their shells 
and across four gills that are specialized for respiration and food 
collection. Food items include detritus (disintegrated organic debris), 
algae, diatoms, and bacteria (Strayer et al. 2004, pp. 430-431). Adults 
are filter feeders and generally orient themselves on or near the 
substrate surface to take in food and oxygen from the water column. 
Juveniles typically burrow completely beneath the substrate surface and 
are pedal (foot) feeders (bringing food particles inside the shell for 
ingestion that adhere to the foot while it is extended outside the 
shell) until the structures for filter feeding are more fully developed 
(Yeager et al. 1994, pp. 200-221; Gatenby et al. 1996, p. 604).
    Sexes in margaritiferid and unionid mussels are usually separate. 
Males release sperm into the water column, which females take in 
through their

[[Page 61484]]

siphons during feeding and respiration. Fertilization takes place 
inside the shell. The eggs are retained in the gills of the female 
until they develop into mature larvae called glochidia. The glochidia 
of most freshwater mussel species, including all eight species 
addressed in this rule, have a parasitic stage during which they must 
attach to the gills, fins, or skin of a fish to transform into a 
juvenile mussel. Depending on the mussel species, females release 
glochidia either separately, in masses known as conglutinates, or in 
one large mass known as a superconglutinate. The duration of the 
parasitic stage varies by mussel species, water temperature, and 
perhaps host fish species. When the transformation is complete, the 
juvenile mussels drop from their fish host and sink to the stream 
bottom where, given suitable conditions, they grow and mature into 
adults.

Survey Data

    Recent distributions are based on surveys conducted from 1995 to 
2011, and historical distributions are based on collections made prior 
to 1995. Historical distribution data from museum records and surveys 
dated between the late 1800s and 1994 are sparse, and most of these 
species were more than likely present throughout their respective river 
basins. Knowledge of historical and current distribution and abundance 
data were summarized from Butler 1989; Williams et al. 2000 
(unpublished), Blalock-Herod et al. 2002, Blalock-Herod et al. 2005, 
Pilarczyk et al. 2006, and Gangloff and Hartfield 2009). These studies 
represent a compilation of museum records and recent status surveys 
conducted between 1990 and 2007. We also used various other sources to 
identify the historical and current locations occupied by these 
species. These include surveys, reports, and field notes prepared by 
biologists from the Alabama Department of Conservation and Natural 
Resources, Marion, AL; Geological Survey of Alabama, Tuscaloosa, AL; 
Florida Fish and Wildlife Conservation Commission, Gainesville, FL; 
U.S. Geological Survey, Gainesville, FL; Alabama Malacological Research 
Center, Mobile, AL; Troy University, Troy, AL; Appalachian State 
University, Boone, NC; various private consulting groups; and the U.S. 
Fish and Wildlife Service, Daphne, AL, and Panama City, FL. In 
addition, we obtained occurrence data from the collection databases of 
the Museum of Fluviatile Mollusks (MFM), Athearn collection; Auburn 
University Natural History Museum (AUNHM), Auburn, Alabama; and Florida 
Museum of Natural History (FLMNH), Gainesville, FL.

Assessing Status

    Assessing the state of a freshwater mussel population is 
challenging. We looked at trends in distribution (range) and abundance 
(numbers), by comparing recent occurrence data to historical data. One 
difficulty of investigating temporal trends in these eight species is 
the lack of historical collection data within the drainages, 
particularly in the lower portion of the main channels. Athearn (1964, 
p. 134) noted the streams of western Florida were inadequately sampled, 
particularly the lower Choctawhatchee, Yellow, and the lower Escambia 
Rivers. Blalock-Herod et al. (2005, p. 2) stated that little collecting 
effort had been expended in the Choctawhatchee River drainage as 
compared to other nearby river systems like the Apalachicola and Mobile 
River drainages. This paucity of historical occurrence data may create 
the appearance of an increase in the number of localities or a larger 
range than historically; however, this is most likely due to increased 
sampling efforts. We also considered each species' relative abundance 
in comparison to other mussel species with which they co-occur. In 
addition, we relied on various published documents whose authors are 
considered experts on these species. These publications either 
described the status of these species or assigned a conservation 
ranking, and include Williams et al. 1993, Garner et al. 2004, Blalock-
Herod et al. 2005, and Williams et al. 2008.
    Most of the eight species have experienced a decline in populations 
and numbers of individuals within populations, but not all have 
experienced a decline in range. Recent, targeted surveys for the 
Alabama pearlshell and southern kidneyshell show a dramatic decline in 
historical range. The southern sandshell, Choctaw bean, narrow pigtoe, 
fuzzy pigtoe and tapered pigtoe still occur in much of their historical 
range; however, their current range is fragmented and their numbers 
appear to be declining.

Taxonomy, Life History, and Distribution

Alabama Pearlshell
    The Alabama pearlshell (Margaritifera marrianae, Johnson 1983) is a 
medium-sized freshwater mussel known from a few tributaries of the 
Alabama and Escambia River drainages in south-central Alabama (Johnson 
1983, pp. 299-304; Mirarchi et al. 2004, p. 40; Williams et al. 2008, 
pp. 98-99). The pearlshell is oblong and grows up to 95 millimeters 
(mm) (3.8 inches (in)) in length. The outside of the shell 
(periostracum) is smooth and shiny and somewhat roughened along the 
posterior slope. The inside of the shell (nacre) is whitish or purplish 
and moderately iridescent (refer to Johnson 1983 for a full 
description).
    The Alabama pearlshell is one of five North American species in the 
family Margaritiferidae. The family is represented by only two genera, 
Margaritifera (Schumacher 1816) and Cumberlandia (Ortmann 1912). In 
Alabama, each genus is represented by a single species. The 
spectaclecase (Cumberlandia monodonta) occurs in the Tennessee River 
Basin (Williams et al. 2008, pp. 94-95) and the Alabama pearlshell 
occurs in the Escambia and Alabama River basins in lower Alabama. Prior 
to 1983, the Alabama pearlshell was thought to be the same species as 
the Louisiana pearlshell (Margaritifera hembeli Conrad 1838) (Simpson 
1914; Clench and Turner 1956), a species now considered endemic to 
central Louisiana.
    The Alabama pearlshell typically inhabits small headwater streams 
with mixed sand and gravel substrates, occasionally in sandy mud, with 
slow to moderate current. Very little is known about the life-history 
requirements of this species. However, Shelton (1995, p. 5 unpub. data) 
suggests that the Alabama pearlshell, as opposed to the Louisiana 
pearlshell, which occurs in large colonies, typically occurs in low 
numbers. The Alabama pearlshell is also believed to occur in male-
female pairs. Of the 68 Alabama pearlshell observed by Shelton (1995, 
p. 5 unpub. data), 85 percent occurred in pairs. Males were always 
located upstream of the females and were typically not more than 1 
meter (m) apart, and juveniles were usually found just a few inches 
apart. The species is believed to be a long-term brooder, where gravid 
females have been observed in December. The host fish and other aspects 
of its life history are currently unknown.
    Historically, the Alabama pearlshell occurred in portions of the 
Escambia River drainage, and has also been reported from two systems in 
the Alabama River drainage. The Alabama pearlshell's known historical 
and current occurrences, by water body and county, are shown in Table 1 
below.

[[Page 61485]]



                                         Table 1--Known Historical and Current Occurrences of Alabama Pearlshell
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             Water body                       Drainage                  County                   State                    Historical or current
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Big Flat Creek......................  Alabama................  Monroe.................  AL....................  Historical and Current.
Brushy Creek........................  Alabama................  Monroe.................  AL....................  Historical.
Limestone Creek.....................  Alabama................  Monroe.................  AL....................  Historical.
Amos Mill Creek.....................  Escambia...............  Conecuh................  AL....................  Current.
Autrey Creek........................  Escambia...............  Conecuh................  AL....................  Historical.
Beaver Creek........................  Escambia...............  Conecuh................  AL....................  Historical.
Bottle Creek........................  Escambia...............  Conecuh................  AL....................  Historical and Current.
Brushy Creek........................  Escambia...............  Conecuh................  AL....................  Historical.
Burnt Corn Creek....................  Escambia...............  Conecuh................  AL....................  Historical and Current.
Horse Creek.........................  Escambia...............  Crenshaw...............  AL....................  Historical.
Hunter Creek........................  Escambia...............  Conecuh................  AL....................  Historical and Current.
Jordan Creek........................  Escambia...............  Conecuh................  AL....................  Historical and Current.
Little Cedar Creek..................  Escambia...............  Conecuh................  AL....................  Historical and Current.
Murder Creek........................  Escambia...............  Conecuh................  AL....................  Historical.
Otter Creek.........................  Escambia...............  Conecuh................  AL....................  Historical and Current.
Sandy Creek.........................  Escambia...............  Conecuh................  AL....................  Historical and Current.
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    The Amos Mill population, discovered in 2010, represents a new 
record, and possibly the only known surviving population in the Sepulga 
River drainage. The Burnt Corn and Otter Creek populations reaffirm 
historical records that had not been reported in nearly 30 years. Two 
of the Sandy Creek locations, discovered in 2011, are new populations. 
Since the late 1990's, more than 70 locations within the Alabama River 
Basin were surveyed for mollusks (McGregor et al. 1999, pp. 13-14; 
Powell and Ford 2010 pers. obs.; Buntin 2011 pers. comm.; Fobian 2011 
pers. comm.), 35 of which were located in the Limestone and Big Flat 
Creek drainages, and no live Alabama pearlshell were reported. The last 
documented occurrence in Big Flat Creek was a fresh dead individual 
collected in 1995 (Shelton 1995, p. 3 unpub. data), and the last 
reported occurrence in the Limestone Creek drainage was 1974 where 
Williams (2009 pers. comm.) reported it as common. Despite numerous 
visits, the pearlshell has not been collected in this system since 
1974. A fresh dead individual, collected by Shelton (1998), represents 
the most recent record from the Big Flat Creek drainage.
    Recent data suggest that, of the nine remaining populations, the 
largest populations may occur in Little Cedar and Otter Mill Creeks. In 
2011, Fobian and Pritchett reported new populations at two locations in 
an unnamed tributary to Sandy Creek. Although this is not the first 
report from the Sandy Creek basin, it is, however, the first for the 
two unnamed tributaries. In 2010, Buntin and Fobian (2011 pers. comm.) 
reported 10 live individuals from Otter Creek. This is the first time 
since 1981 that the pearlshell has been reported from this drainage. 
Also in 2010, Powell and Ford reported 3 individuals, and several relic 
shells, from Amos Mill Creek, in Escambia County, AL. This is the first 
report of the pearlshell from this drainage, and county, and the first 
live individual from the Sepulga River system in nearly 50 years. 
Little Cedar Creek supported good numbers of Alabama pearlshell in the 
late 1990's (54 individuals reported in 1998). However, during a 
qualitative search of the same area in 2005, only two live pearlshell 
were found (Powell 2005 pers. obs.), and in 2006, three live 
pearlshells were observed (Johnson 2006 in litt.). Live Alabama 
pearlshell have not been observed in Hunter Creek since 1998, when 
eight live individuals were reported (Shelton 1998 pers. comm.). During 
two visits to the stream in 1999, Shelton found no evidence of the 
species (Shelton 1999 in litt.), and reported high levels of 
sedimentation. However, in 2005 the shells of three fresh dead Alabama 
pearlshells were reported from Hunter Creek, indicating the persistence 
of the species in that drainage (Powell, pers. obs. 2005).
    Evidence suggests that much of the rangewide decline of this 
species has occurred within the past few decades. Specific causes of 
the decline and disappearance of the Alabama pearlshell from historical 
stream localities are unknown. However, they are likely related to past 
and present land use patterns. Many of the small streams historically 
inhabited by the Alabama pearlshell are impacted to various degrees by 
nonpoint-source pollution.
Round Ebonyshell
    The round ebonyshell (Fusconaia rotulata, Wright 1899) is a medium-
sized freshwater mussel endemic to the Escambia River drainage in 
Alabama and Florida (Williams et al. 2008, p. 320). The round 
ebonyshell is round to oval in shape and reaches about 70 mm (2.8 in.) 
in length. The shell is thick and the outside is smooth and dark brown 
to black in color. The shell interior is white to silvery and 
iridescent (Williams and Butler 1994, p. 61; Williams et al. 2008, p. 
319). The round ebonyshell was originally described by B. H. Wright in 
1899 and placed in the genus Unio. Simpson (1900) reexamined the type 
specimen and assigned it to the genus Obovaria. Based on shell 
characters, Williams and Butler (1994, p. 61) recognized it as clearly 
a species of the genus Fusconaia, and its placement in the genus is 
supported genetically (Lydeard et al. 2000, p. 149).
    Very little is known about the habitat requirements or life history 
of the round ebonyshell. It occurs typically in stable substrates of 
sand, small gravel, or sandy mud in slow to moderate current. It is 
believed to be a short-term brooder, and gravid females have been 
observed in the spring and summer. The fish host(s) for the round 
ebonyshell is currently unknown (Williams et al. 2008, p. 320).
    The round ebonyshell is known only from the main channel of the 
Escambia-Conecuh River and is the only mussel species endemic to the 
drainage (Williams et al. 2008, p. 320). Due to recent survey data, its 
known range was extended downstream the Escambia River to near Mystic 
Springs in Florida (Shelton et al. 2007, p. 9 unpub. data), and 
upstream the Conecuh River to just above the Covington County line in 
Alabama (Williams et al. 2008, p. 320). The round ebonyshell's known 
historical and current occurrences, by water body and county, are shown 
in Table 2 below.

[[Page 61486]]



                                        Table 2--Known Historical and Current Occurrences of the Round Ebonyshell
--------------------------------------------------------------------------------------------------------------------------------------------------------
             Water body                       Drainage                  County                   State                    Historical or current
--------------------------------------------------------------------------------------------------------------------------------------------------------
Conecuh River.......................  Escambia...............  Escambia, Covington....  AL....................  Historical and Current.
Escambia River......................  Escambia...............  Escambia, Santa Rosa...  FL....................  Historical and Current.
--------------------------------------------------------------------------------------------------------------------------------------------------------

    The round ebonyshell has one of the most restricted distributions 
of any North American unionid (Williams and Butler 1994, p. 61). Its 
current range (based on live individuals and shell material) is 
confined to approximately 120 km (75 mi) of river channel. The round 
ebonyshell is also extremely rare (Williams et al. 2008, p. 320). 
Researchers collected a total of three live individuals during a 2006 
status survey (Shelton et al. 2007, pp. 8-10 unpub. data). At stations 
where the species was present, roughly 950 mussels were collected for 
every 1 round ebonyshell. Its limited distribution and small population 
size makes round ebonyshell particularly vulnerable to catastrophic 
events such as droughts, flood scour, and contaminant spills. Due to 
its limited distribution and rarity, Garner et al. (2004, p. 56) 
considered the round ebonyshell vulnerable to extinction, and 
classified it as a species of highest conservation concern in Alabama. 
Williams et al. (1993, p. 11) considered the round ebonyshell as 
endangered throughout its range.
Southern Sandshell
    The southern sandshell (Hamiota australis, Simpson 1900) is a 
medium-sized freshwater mussel known from the Escambia River drainage 
in Alabama, and the Yellow and Choctawhatchee River drainages in 
Alabama and Florida (Williams et al. 2008, p. 338). The southern 
sandshell is elliptical in shape and reaches about 83 mm (2.3 in.) in 
length. Its shell is smooth and shiny, and greenish in color in young 
specimens, becoming dark greenish brown to black with age, with many 
variable green rays. The shell interior is bluish white and iridescent. 
Sexual dimorphism is present as a slight inflation of the 
posterioventral shell margin of females (Williams and Butler 1994, p. 
97; Williams et al. 2008, p. 337). The southern sandshell (Hamiota 
australis) was originally described by C. T. Simpson (1900) as 
Lampsilis australis. Heard (1979), however, designated it as a species 
of Villosa. It was placed in the genus Hamiota by Roe and Hartfield 
(2005, pp. 1-3) who confirmed earlier published suggestions by Fuller 
and Bereza (1973, p. 53) and O'Brien and Brim Box (1999, pp. 135-136) 
that this species and three others of the genus Lampsilis represent a 
distinct genus. This separation from other Lampsilis is supported 
genetically (Roe et al. 2001, p. 2230). The new genus, Hamiota, is 
distinguished based on several characters including unique shape and 
placement of the marsupia (where females brood developing larvae), and 
production of a single large conglutinate, termed a superconglutinate.
    The southern sandshell is typically found in small creeks and 
rivers in stable substrates of sand or mixtures of sand and fine 
gravel, with slow to moderate current. It is a long-term brooder, and 
females are gravid from late summer or autumn to the following spring 
(Williams et al. 2008, p. 338). The southern sandshell is one of only 
four species that produce a superconglutinate to attract a host. A 
superconglutinate is a mass that mimics the shape, coloration, and 
movement of a fish and is produced by the female mussel to hold the 
glochidia (larval mussels) from one year's reproductive effort (Haag et 
al. 1995, p. 472). After release, the superconglutinate is tethered to 
the female mussel by a mucus strand, and it appears to dart and swim in 
the current. Although the fish host for the southern sandshell has not 
been identified, it likely uses predatory sunfishes such as basses, 
like other Hamiota species (Haag et al. 1995, p. 475; O'Brien and Brim 
Box 1999, p. 134; Blalock-Herod et al. 2002, p. 1885).
    The southern sandshell is endemic to the Escambia River drainage in 
Alabama, and the Yellow and Choctawhatchee River drainages in Alabama 
and Florida (Blalock-Herod et al. 2002, pp. 1882, 1884). The southern 
sandshell's known historical and current occurrences, by water body and 
county, are shown in Table 3 below.

                                       Table 3--Known Historical and Current Occurrences of the Southern Sandshell
--------------------------------------------------------------------------------------------------------------------------------------------------------
             Water body                       Drainage                  County                   State                    Historical or current
--------------------------------------------------------------------------------------------------------------------------------------------------------
Alligator Creek.....................  Choctawhatchee.........  Washington.............  FL....................  Historical.
Bruce Creek.........................  Choctawhatchee.........  Walton.................  FL....................  Current.
Choctawhatchee River................  Choctawhatchee.........  Geneva.................  AL....................  Historical.
Choctawhatchee River................  Choctawhatchee.........  Holmes, Dale...........  FL, AL................  Historical and Current.
Corner Creek........................  Choctawhatchee.........  Geneva.................  AL....................  Current.
Double Bridges Creek................  Choctawhatchee.........  Coffee.................  AL....................  Current.
East Fork Choctawhatchee R..........  Choctawhatchee.........  Henry..................  AL....................  Historical and Current.
East Fork Choctawhatchee R..........  Choctawhatchee.........  Dale...................  AL....................  Historical.
Eightmile Creek.....................  Choctawhatchee.........  Walton, Geneva.........  FL, AL................  Current.
Flat Creek..........................  Choctawhatchee.........  Geneva.................  AL....................  Current.
Holmes Creek........................  Choctawhatchee.........  Holmes.................  FL....................  Historical.
Jordan Creek........................  Choctawhatchee.........  Conecuh................  AL....................  Current.
Limestone Creek.....................  Choctawhatchee.........  Walton.................  FL....................  Historical.
Little Choctawhatchee River.........  Choctawhatchee.........  Dale, Houston..........  AL....................  Historical.
Natural Bridge Creek................  Choctawhatchee.........  Geneva.................  AL....................  Current.
Patsaliga Creek.....................  Choctawhatchee.........  Crenshaw...............  AL....................  Current.
Pauls Creek.........................  Choctawhatchee.........  Barbour................  AL....................  Current.
Pea Creek (Barbour Co.).............  Choctawhatchee.........  Barbour................  AL....................  Historical and Current.
Pea Creek (Dale Co.)................  Choctawhatchee.........  Dale...................  AL....................  Historical.
Pea River...........................  Choctawhatchee.........  Geneva, Barbour........  AL....................  Historical.
Pea River...........................  Choctawhatchee.........  Coffee, Dale, Pike.....  AL....................  Historical and Current.
Sikes Creek.........................  Choctawhatchee.........  Barbour................  AL....................  Current.

[[Page 61487]]

 
Tenmile Creek.......................  Choctawhatchee.........  Holmes.................  FL....................  Historical.
West Fork Choctawhatchee R..........  Choctawhatchee.........  Barbour, Dale..........  AL....................  Historical and Current.
Whitewater Creek....................  Choctawhatchee.........  Coffee.................  AL....................  Historical.
Wrights Creek.......................  Choctawhatchee.........  Holmes.................  FL....................  Current.
Burnt Corn Creek....................  Escambia...............  Escambia, Conecuh......  AL....................  Historical.
Conecuh River.......................  Escambia...............  Pike...................  AL....................  Current.
Conecuh River.......................  Escambia...............  Covington, Crenshaw....  AL....................  Historical.
Little Patsaliga Creek..............  Escambia...............  Crenshaw...............  AL....................  Historical.
Sepulga River.......................  Escambia...............  Conecuh................  AL....................  Historical.
Five Runs Creek.....................  Yellow.................  Covington..............  AL....................  Historical and Current.
Pond Creek..........................  Yellow.................  Okaloosa, Walton.......  FL....................  Historical.
Shoal River.........................  Yellow.................  Okaloosa...............  FL....................  Current.
Yellow River........................  Yellow.................  Okaloosa...............  FL....................  Current.
Yellow River........................  Yellow.................  Covington..............  AL....................  Historical and Current.
--------------------------------------------------------------------------------------------------------------------------------------------------------

    The southern sandshell persists in its historical range; however, 
its range is fragmented and numbers appear to be declining (Williams et 
al. 2008, p. 338). The number of locations in the Escambia drainage 
known to support the species has declined. It is known from a total of 
nine locations, however, only three are recent occurrences. Also, its 
numbers are very low; a total of four individuals (live and shell 
material) have been collected in the Escambia drainage since 1995. In 
the Yellow River drainage, the number of locations known to support 
southern sandshell populations has declined from a total of 15 to 10 
currently. The number of locations known to support the species in the 
Choctawhatchee River drainage has declined from 44 to 25 currently; and 
it may be extirpated from central portions of the Choctawhatchee River 
main channel and from some of its tributaries. Sedimentation could be 
one factor contributing to its decline. In order to reproduce, the 
southern sandshell must attract a site-feeding fish to its 
superconglutinate lure. Waters clouded by silt and sediment would 
reduce the chance of this interaction occurring (Haag et al. 1995, p. 
475).
    The southern sandshell is classified as a species of highest 
conservation concern in Alabama by Garner et al. (2004, p. 60), and 
considered threatened throughout its range by Williams et al. (1993, p. 
11).
Southern Kidneyshell
    The southern kidneyshell (Ptychobranchus jonesi, van der Schalie 
1934) is a medium-sized freshwater mussel known from the Escambia and 
Choctawhatchee River drainages in Alabama and Florida, and the Yellow 
River drainage in Alabama (Williams et al. 2008, p. 624). The southern 
kidneyshell is elliptical and reaches about 72 mm (2.8 in.) in length. 
Its shell is smooth and shiny, and greenish yellow to dark brown or 
black in color, sometimes with weak rays. The shell interior is bluish 
white with some iridescence (Williams and Butler 1994, p. 126; Williams 
et al. 2008, p. 624). The southern kidneyshell was described by H. van 
der Schalie (1934) as Lampsilis jonesi. Following the examination of 
gills of gravid females, Fuller and Bereza (1973, p. 53) determined it 
belonged in the genus Ptychobranchus. When gravid, the marsupial gills 
form folds along the outer edge, a characteristic unique to the genus 
Ptychobranchus (Williams et al. 2008, p. 609).
    Very little is known about the habitat requirements or life history 
of the southern kidneyshell. It is typically found in medium creeks to 
medium rivers in firm sand substrates with slow to moderate current 
(Williams et al. 2008, pp. 625). A recent status survey in the 
Choctawhatchee basin in Alabama found its preferred habitat to be 
stable substrates near bedrock outcroppings (Gangloff and Hartfield 
2009, p. 25). The southern kidneyshell is believed to be a long-term 
brooder, with females gravid from autumn to the following spring or 
summer. Preliminary reproductive studies found that females release 
their glochidia in small conglutinates that are bulbous at one end and 
tapered at the other (Alabama Aquatic Biodiversity Center 2006 unpub. 
data). Host fish for the southern kidneyshell are currently unknown; 
however, darters serve as primary glochidial hosts to other members of 
the genus Ptychobranchus (Luo 1993, p. 16; Haag and Warren 1997, p. 
580).
    The southern kidneyshell is endemic to the Escambia, 
Choctawhatchee, and Yellow River drainages in Alabama and Florida 
(Williams et al. 2008, p. 624), but is currently known only from the 
Choctawhatchee drainage. The southern kidneyshell's known historical 
and current occurrences, by water body and county, are shown in Table 4 
below.

                                      Table 4--Known Historical and Current Occurrences of the Southern Kidneyshell
--------------------------------------------------------------------------------------------------------------------------------------------------------
             Water body                       Drainage                  County                   State                    Historical or current
--------------------------------------------------------------------------------------------------------------------------------------------------------
Choctawhatchee River................  Choctawhatchee.........  Dale...................  AL....................  Historical and Current.
Choctawhatchee River................  Choctawhatchee.........  Walton, Geneva.........  FL, AL................  Historical.
East Fork Choctawhatchee R..........  Choctawhatchee.........  Dale, Henry............  AL....................  Historical.
Flat Creek..........................  Choctawhatchee.........  Geneva.................  AL....................  Historical.
Holmes Creek........................  Choctawhatchee.........  Washington.............  AL....................  Current.
Pea River...........................  Choctawhatchee.........  Geneva.................  AL....................  Current.
Pea River...........................  Choctawhatchee.........  Pike, Barbour..........  AL....................  Historical.
Pea River...........................  Choctawhatchee.........  Coffee, Dale...........  AL....................  Historical and Current.
Sandy Creek.........................  Choctawhatchee.........  Walton.................  FL....................  Historical.
West Fork Choctawhatchee R..........  Choctawhatchee.........  Barbour................  AL....................  Historical and Current.
West Fork Choctawhatchee R..........  Choctawhatchee.........  Dale...................  AL....................  Historical.
Whitewater Creek....................  Choctawhatchee.........  Coffee.................  AL....................  Historical.

[[Page 61488]]

 
Burnt Corn Creek....................  Escambia...............  Escambia...............  AL....................  Historical.
Conecuh River.......................  Escambia...............  Covington, Crenshaw....  AL....................  Historical.
Jordan Creek........................  Escambia...............  Conecuh................  AL....................  Historical.
Little Patsaliga Creek..............  Escambia...............  Crenshaw...............  AL....................  Historical.
Patsaliga Creek.....................  Escambia...............  Covington, Crenshaw....  AL....................  Historical.
Sepulga River.......................  Escambia...............  Conecuh................  AL....................  Historical.
Hollis Creek........................  Yellow.................  Covington..............  AL....................  Historical.
--------------------------------------------------------------------------------------------------------------------------------------------------------

    Since 1995, the southern kidneyshell has been detected at only 10 
locations within the Choctawhatchee River drainage. The species appears 
to have been common historically (In 1964, H. D. Athearn collected 98 
individuals at one site on the West Fork Choctawhatchee), but it is 
currently considered one of the most imperiled species in the United 
States (Blalock-Herod et al. 2005, p. 16; Williams et al. 2008, p. 
625). In addition to a reduction in range, its population numbers also 
appear to be very low. A 2006-2007 status survey in the Alabama 
portions of the Choctawhatchee basin found the southern kidneyshell was 
extremely rare. A total of 13 were encountered alive, and the species 
comprised less than 0.3 percent of the total mussel assemblage 
(Gangloff and Hartfield 2009, p. 249). It is classified as a species of 
highest conservation concern in Alabama by Garner et al. (2004, p. 83), 
and considered threatened throughout its range by Williams et al. 
(1993, p. 14)
Choctaw Bean
    The Choctaw bean (Villosa choctawensis, Athearn 1964) is a small 
freshwater mussel known from the Escambia, Yellow, and Choctawhatchee 
River drainages of Alabama and Florida. The oval shell of the Choctaw 
bean reaches about 49 mm (2.0 in.) in length, and is shiny and 
greenish-brown in color, typically with thin green rays, though the 
rays are often obscured in darker individuals. The shell interior color 
varies from bluish white to smoky brown with some iridescence (Williams 
and Butler 1994, p. 100; Williams et al. 2008, p. 758). The sexes are 
dimorphic, with females truncate or widely rounded posteriorly, and 
sometimes slightly more inflated (Athearn 1964, p. 137). The Choctaw 
bean was originally described by H. D. Athearn in 1964.
    Very little is known about the habitat requirements or life history 
of the Choctaw bean. It is found in large creeks and small rivers in 
stable substrates of silty sand to sandy clay with moderate current. It 
is believed to be a long-term brooder, with females gravid from late 
summer or autumn to the following summer. Its fish host is currently 
unknown (Williams et al. 2008, p. 758).
    The Choctaw bean is known from the Escambia, Yellow, and 
Choctawhatchee River drainages in Alabama and Florida (Williams et al. 
2008, p. 758). The Choctaw bean's known historical and current 
occurrences, by water body and county, are shown in the table below.

                                         Table 5--Known Historical and Current Occurrences for the Choctaw Bean
--------------------------------------------------------------------------------------------------------------------------------------------------------
             Water body                       Drainage                  County                   State                    Historical or current
--------------------------------------------------------------------------------------------------------------------------------------------------------
Big Sandy Creek.....................  Choctawhatchee.........  Bullock................  AL....................  Current.
Bruce Creek.........................  Choctawhatchee.........  Walton.................  FL....................  Current.
Choctawhatchee River................  Choctawhatchee.........  Dale...................  AL....................  Current.
Choctawhatchee River................  Choctawhatchee.........  Holmes.................  AL....................  Historical.
Choctawhatchee River................  Choctawhatchee.........  Washington, Geneva.....  FL, AL................  Historical and Current.
Claybank Creek......................  Choctawhatchee.........  Dale...................  AL....................  Current.
East Fork Choctawhatchee R..........  Choctawhatchee.........  Barbour................  AL....................  Current.
East Fork Choctawhatchee R..........  Choctawhatchee.........  Henry..................  AL....................  Historical and Current.
Flat Creek..........................  Choctawhatchee.........  Geneva.................  AL....................  Current.
Holmes Creek........................  Choctawhatchee.........  Washington.............  FL....................  Current.
Judy Creek..........................  Choctawhatchee.........  Dale...................  AL....................  Current.
Limestone Creek.....................  Choctawhatchee.........  Walton.................  FL....................  Current.
Paul's Creek........................  Choctawhatchee.........  Barbour................  AL....................  Current.
Pea Creek...........................  Choctawhatchee.........  Barbour................  AL....................  Current.
Pea River...........................  Choctawhatchee.........  Coffee.................  AL....................  Current.
Pea River...........................  Choctawhatchee.........  Geneva, Pike, Barbour..  AL....................  Historical and Current.
West Fork Choctawhatchee R..........  Choctawhatchee.........  Dale...................  AL....................  Current.
West Fork Choctawhatchee R..........  Choctawhatchee.........  Pike, Barbour..........  AL....................  Historical and Current.
Whitewater Creek....................  Choctawhatchee.........  Coffee.................  AL....................  Current.
Wrights Creek.......................  Choctawhatchee.........  Holmes.................  FL....................  Current.
Conecuh River.......................  Escambia...............  Crenshaw, Pike.........  AL....................  Current.
Escambia River......................  Escambia...............  Santa Rosa.............  FL....................  Historical.
Escambia River......................  Escambia...............  Escambia...............  FL....................  Historical and Current.
Little Patsaliga Creek..............  Escambia...............  Crenshaw...............  AL....................  Historical.
Murder Creek........................  Escambia...............  Conecuh................  AL....................  Historical.
Olustee Creek.......................  Escambia...............  Pike...................  AL....................  Current.
Patsaliga Creek.....................  Escambia...............  Crenshaw...............  AL....................  Historical and Current.
Pigeon Creek........................  Escambia...............  Butler.................  AL....................  Historical.
Five Runs Creek.....................  Yellow.................  Covington..............  AL....................  Historical and Current.
Yellow River........................  Yellow.................  Okaloosa, Covington....  FL, AL................  Historical and Current.
--------------------------------------------------------------------------------------------------------------------------------------------------------


[[Page 61489]]

    The Choctaw bean persists in most of its historical range. However, 
its populations are fragmented and its numbers are low, particularly in 
the Escambia and Yellow drainages. The number of locations in the 
Escambia River drainage known to support the species has declined from 
a total of 13 to 6 currently. Also, its numbers within the drainage are 
very low; a total of only 10 individuals have been collected since 
1995. The number of locations known to support the Choctaw bean in the 
Yellow River drainage has declined from a total of 7 to 4 currently. 
Since 1995, a total of 28 individuals have been collected within the 
Yellow drainage. In the Choctawhatchee River drainage, the Choctaw bean 
continues to persist in most areas. It is known from a total of 40 
locations throughout the drainage, 34 of which are recent occurrences.
    Heard assessed the status of the Choctaw bean in 1975 (p. 17) and 
stated that it was formerly abundant in the main channel of the 
Choctawhatchee River in Florida, but has become quite rare. Garner et 
al. (2004, p. 103) considered the Choctaw bean vulnerable to extinction 
due to its limited distribution and habitat degradation, and classified 
it as a species of high conservation concern in Alabama. Williams et 
al. (1993, p. 14) considered the Choctaw bean as threatened throughout 
its range.
Tapered Pigtoe
    The tapered pigtoe (Fusconaia burkei, Walker 1922) is a small to 
medium-sized mussel endemic to the Choctawhatchee river drainage in 
Alabama and Florida (Williams et al. 2008, p. 296). The elliptical to 
subtriangular shell of the tapered pigtoe reaches about 75 mm (3.0 in.) 
in length, and is sculptured with plications (parallel ridges) that 
radiate from the posterior ridge. In younger individuals, the shell 
exterior is greenish brown to yellowish brown in color, occasionally 
with faint dark-green rays, and with pronounced sculpture often 
covering the entire shell; in older individuals the shell becomes dark 
brown to black with age and sculpture is often subtle. The shell 
interior is bluish white (Williams et al. 2008, p. 295). The tapered 
pigtoe was described by B. Walker (1922) (in Ortmann and Walker) as 
Quincuncina burkei, a new genus and species (the genus description was 
done by A. E. Ortmann and the species description by Walker). In the 
description, Ortmann noted the species had gill features characteristic 
of the genus Fusconaia; however, this was dismissed based on the 
presence of sculpture on the shell. Genetic analysis by Lydeard et al. 
(2000, p. 149) determined it to be a sister taxon to Fusconaia 
escambia. Based on genetic results and soft anatomy similarity, 
Williams et al. (2008, p. 296) recognized burkei as belonging to the 
genus Fusconaia.
    The tapered pigtoe is found in small to medium rivers in stable 
substrates of sand, small gravel, or sandy mud, with slow to moderate 
current (Williams et al. 2008, p. 296). The reproductive biology of the 
tapered pigtoe was studied by White et al. (2008). It is a short-term 
brooder, with females gravid from mid-March to May. The blacktail 
shiner (Cyprinella venusta) was found to serve as a host for tapered 
pigtoe glochidia in the preliminary host trial (White et al. 2008, p. 
122-123).
    The tapered pigtoe is endemic to the Choctawhatchee River drainage 
in Alabama and Florida (Williams et al. 2008, p. 296). Its historical 
and current distribution includes several oxbow lakes in Florida; some 
with a flowing connection to main channel. The tapered pigtoe's known 
historical and current occurrences, by water body and county, are shown 
in the table below.

                                        Table 6--Known Historical and Current Occurrences for the Tapered Pigtoe
--------------------------------------------------------------------------------------------------------------------------------------------------------
             Water body                       Drainage                  County                   State                    Historical or current
--------------------------------------------------------------------------------------------------------------------------------------------------------
Bear Creek..........................  Choctawhatchee.........  Houston................  AL....................  Historical.
Big Creek...........................  Choctawhatchee.........  Barbour................  AL....................  Current.
Blue Creek..........................  Choctawhatchee.........  Holmes.................  FL....................  Current.
Bruce Creek.........................  Choctawhatchee.........  Walton.................  FL....................  Current.
Choctawhatchee River................  Choctawhatchee.........  Dale...................  AL....................  Historical.
Choctawhatchee River................  Choctawhatchee.........  Washington, Walton,      FL....................  Historical and Current.
                                                                Holmes.
Cowford Island channel..............  Choctawhatchee.........  Washington.............  FL....................  Historical and Current.
Crawford Lake.......................  Choctawhatchee.........  Washington.............  FL....................  Historical.
Crews Lake..........................  Choctawhatchee.........  Washington.............  FL....................  Current.
East Fork Choctawhatchee R..........  Choctawhatchee.........  Dale...................  AL....................  Historical.
East Fork Choctawhatchee R..........  Choctawhatchee.........  Henry..................  AL....................  Historical and Current.
East Pittman Creek..................  Choctawhatchee.........  Holmes.................  FL....................  Historical and Current.
Eightmile Creek.....................  Choctawhatchee.........  Walton, Geneva.........  FL, AL................  Current.
Flat Creek..........................  Choctawhatchee.........  Geneva.................  AL....................  Historical and Current.
Holmes Creek........................  Choctawhatchee.........  Washington, Holmes,      FL....................  Historical and Current.
                                                                Jackson.
Horseshoe Lake......................  Choctawhatchee.........  Washington.............  FL....................  Historical.
Hurricane Creek.....................  Choctawhatchee.........  Geneva.................  AL....................  Historical.
Judy Creek..........................  Choctawhatchee.........  Dale...................  AL....................  Current.
Limestone Creek.....................  Choctawhatchee.........  Walton.................  FL....................  Historical and Current.
Little Choctawhatchee River.........  Choctawhatchee.........  Dale, Houston..........  AL....................  Historical.
Panther Creek.......................  Choctawhatchee.........  Houston................  AL....................  Historical.
Parrot Creek........................  Choctawhatchee.........  Holmes.................  FL....................  Current.
Paul's Creek........................  Choctawhatchee.........  Barbour................  AL....................  Current.
Pea Creek...........................  Choctawhatchee.........  Barbour................  AL....................  Current.
Pea River...........................  Choctawhatchee.........  Dale, Barbour..........  AL....................  Historical.
Pea River...........................  Choctawhatchee.........  Coffee, Pike...........  AL....................  Historical and Current.
Pine Log Creek......................  Choctawhatchee.........  Washington, Bay........  FL....................  Current.
Sandy Creek.........................  Choctawhatchee.........  Walton.................  FL....................  Current.
Tenmile Creek.......................  Choctawhatchee.........  Holmes.................  FL....................  Historical.
West Fork Choctawhatchee R..........  Choctawhatchee.........  Dale, Pike.............  AL....................  Historical.
West Fork Choctawhatchee R..........  Choctawhatchee.........  Barbour................  AL....................  Historical and Current.
West Pittman Creek..................  Choctawhatchee.........  Holmes.................  FL....................  Current.

[[Page 61490]]

 
Wrights Creek.......................  Choctawhatchee.........  Holmes.................  FL....................  Current.
--------------------------------------------------------------------------------------------------------------------------------------------------------

    The tapered pigtoe appears to be absent from portions of its 
historical range and found only in isolated locations (Blalock-Herod et 
al. 2005, p. 17). The species is known from a total of 60 locations 
within the Choctawhatchee River drainage. It was not detected at 11 
historical sites examined during recent status surveys (9 additional 
historic locations were not examined). Many of those historic 
occurrences are in the middle section of the drainage, and the species 
appears to be declining in that portion of its range. The tapered 
pigtoe continues to persist in isolated locations, mainly in the 
Choctawhatchee River main channel in Florida and in the headwaters in 
Alabama.
    Due to its limited distribution, rarity, and habitat degradation, 
Garner et al. (2004, p. 105) consider the tapered pigtoe vulnerable to 
extinction, and classified it as a species of high conservation concern 
in Alabama. The tapered pigtoe is considered threatened throughout its 
range by Williams et al. (1993, p. 14).
Narrow Pigtoe
    The narrow pigtoe (Fusconaia escambia, Clench and Turner 1956) is a 
small to medium-sized mussel known from the Escambia River drainage in 
Alabama and Florida, and the Yellow River drainage in Florida. The 
subtriangular to squarish shaped shell of the narrow pigtoe reaches 
about 75 mm (3.0 in.) in length. The shell is moderately thick and is 
usually reddish brown to black in color. The shell interior is white to 
salmon in color with iridescence near the posterior margin (Williams 
and Butler 1994, p. 77; Williams et al. 2008, p. 316). The narrow 
pigtoe was originally described by W.J. Clench and R.D. Turner in 1956.
    Little is known about the habitat requirements or life history of 
the narrow pigtoe. It is found in creeks and small to medium rivers in 
stable substrates of sand, s