[Federal Register Volume 77, Number 30 (Tuesday, February 14, 2012)]
[Rules and Regulations]
[Pages 8632-8665]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2012-2940]



[[Page 8631]]

Vol. 77

Tuesday,

No. 30

February 14, 2012

Part VI





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; Determination of 
Endangered Status for the Rayed Bean and Snuffbox Mussels Throughout 
Their Ranges; Final Rule

  Federal Register / Vol. 77 , No. 30 / Tuesday, February 14, 2012 / 
Rules and Regulations  

[[Page 8632]]


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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

[Docket No. FWS-R3-ES-2010-0019; 4500030113]
RIN 1018-AV96


Endangered and Threatened Wildlife and Plants; Determination of 
Endangered Status for the Rayed Bean and Snuffbox Mussels Throughout 
Their Ranges

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Final rule.

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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), determine 
endangered status for the rayed bean (Villosa fabalis) and snuffbox 
(Epioblasma triquetra) mussels throughout their ranges, under the 
Endangered Species Act of 1973, as amended (Act).

DATES: This rule becomes effective on March 15, 2012.

ADDRESSES: This final rule is available on the Internet at http://www.regulations.gov at Docket Number FWS-R3-ES-2010-0019. 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, Columbus Ecological Services Field Office, 4625 Morse 
Road, Suite 104, Columbus, OH 43230; phone 614-416-8993; facsimile 614-
416-8994.

FOR FURTHER INFORMATION CONTACT: Angela Boyer, Endangered Species 
Coordinator, Columbus Ecological Services Field Office (see ADDRESSES). 
If you use a telecommunications devise for the deaf (TDD), call the 
Federal Information Relay Service (FIRS) at 800-877-8339.

SUPPLEMENTARY INFORMATION:

Background

    This document is a final rule to list as endangered the rayed bean 
(Villosa fabalis) and snuffbox (Epioblasma triquetra).

Previous Federal Action

    Federal actions for these species prior to November 2, 2010, are 
outlined in our proposed rule for these actions (75 FR 67552). 
Publication of the proposed rule opened a 60-day comment period, which 
ended on January 3, 2011.

Species Information

Rayed Bean
    The rayed bean is a small mussel, usually less than 1.5 inches (in) 
(3.8 centimeters (cm)) in length (Cummings and Mayer 1992, p. 142; 
Parmalee and Bogan 1998, p. 244; West et al. 2000, p. 248). The shell 
outline is elongate or ovate in males and elliptical in females, and 
moderately inflated in both sexes, but more so in females (Parmalee and 
Bogan 1998, p. 244). The valves are thick and solid. The anterior end 
is rounded in females and bluntly pointed in males (Cummings and Mayer 
1992, p. 142). Females are generally smaller than males (Parmalee and 
Bogan 1998, p. 244). Dorsally, the shell margin is straight, while the 
ventral margin is straight to slightly curved (Cummings and Mayer 1992, 
p. 142). The beaks are slightly elevated above the hingeline (West et 
al. 2000, p. 248), with sculpture consisting of double loops with some 
nodules (Parmalee and Bogan 1998, p. 244). No posterior ridge is 
evident. Surface texture is smooth and sub-shiny, and green, yellowish-
green, or brown in color, with numerous, wavy, dark-green rays of 
various widths (sometimes obscure in older, blackened specimens) 
(Cummings and Mayer 1992, p. 142; West et al. 2000, p. 248). 
Internally, the left valve has two pseudocardinal teeth (tooth-like 
structures along the hingeline of the internal portion of the shell) 
that are triangular, relatively heavy, and large, and two short, heavy 
lateral teeth (Cummings and Mayer 1992, p. 142). The right valve has a 
low, triangular pseudocardinal tooth, with possibly smaller secondary 
teeth anteriorly and posteriorly, and a short, heavy, and somewhat 
elevated lateral tooth (Parmalee and Bogan 1998, p. 244). The color of 
the nacre (mother-of-pearl) is silvery white or bluish and iridescent 
posteriorly. Key characters useful for distinguishing the rayed bean 
from other mussels are its small size, thick valves, unusually heavy 
teeth for a small mussel, and color pattern (Cummings and Mayer 1992, 
p. 142).
Snuffbox
    The snuffbox is a small- to medium-sized mussel, with males 
reaching up to 2.8 in (7.0 cm) in length (Cummings and Mayer 1992, p. 
162; Parmalee and Bogan 1998, p. 108). The maximum length of females is 
about 1.8 in (4.5 cm) (Parmalee and Bogan 1998, p. 108). The shape of 
the shell is somewhat triangular (females), oblong, or ovate (males), 
with the valves solid, thick, and very inflated. The beaks are located 
somewhat anterior of the middle, and are swollen, turned forward and 
inward, and extended above the hingeline (Cummings and Mayer 1992, p. 
162). Beak sculpture consists of three or four faint, double-looped 
bars (Cummings and Mayer 1992, p. 162; Parmalee and Bogan 1998, p. 
108). The anterior end of the shell is rounded, and the posterior end 
is truncated, highly so in females. The posterior ridge is prominent, 
being high and rounded, while the posterior slope is widely flattened. 
The posterior ridge and slope in females is covered with fine ridges 
and grooves, and the posterioventral shell edge is finely toothed 
(Cummings and Mayer 1992, p. 162). When females are viewed from a 
dorsal or ventral perspective, the convergence of the two valves on the 
posterior slope is nearly straight due to being highly inflated. This 
gives the female snuffbox a unique, broadly lanceolate or cordate 
perspective when viewed at the substrate and water column interface 
(Ortmann 1919, p. 329; van der Schalie 1932, p. 104). The ventral 
margin is slightly rounded in males and nearly straight in females. 
Females have recurved denticles (downward curved tooth-like structures) 
on the posterior shell margin that aid in holding host fish (Barnhart 
2008, p. 1). The periostracum (external shell surface) is generally 
smooth and yellowish or yellowish-green in young individuals, becoming 
darker with age. Green, squarish, triangular, or chevron-shaped marks 
cover the umbone (the inflated area of the shell along the dorsal 
margin), but become poorly delineated stripes with age. Internally, the 
left valve has two high, thin, triangular, emarginate pseudocardinal 
teeth (the front tooth being thinner than the back tooth) and two 
short, strong, slightly curved, and finely striated lateral teeth. The 
right valve has a high, triangular pseudocardinal tooth with a single 
short, erect, and heavy lateral tooth. The interdentum (a flattened 
area between the pseudocardinal and lateral teeth) is absent, and the 
beak cavity is wide and deep. The color of the nacre is white, often 
with a silvery luster, and a gray-blue or gray-green tinge in the beak 
cavity. The soft anatomy was described by Oesch (1984, pp. 233-234) and 
Williams et al. (2008, p. 282). Key characters useful for 
distinguishing the snuffbox from other species include its unique color 
pattern, shape (especially in females), and high degree of inflation.
Taxonomy
    The rayed bean is a member of the freshwater mussel family 
Unionidae and was originally described as Unio fabalis by Lea in 1831 
(pp. 86-87). The type locality (the location of the first

[[Page 8633]]

identified specimen) is the Ohio River (Parmalee and Bogan 1998, p. 
244), probably in the vicinity of Cincinnati, Ohio. Over the years, the 
rayed bean has been placed in the genera Unio, Margarita, Margaron, 
Eurynia, Micromya, and Lemiox. It was ultimately placed in the genus 
Villosa by Stein (1963, p. 19), where it remains today (Turgeon et al. 
1998, p. 33). We recognize Unio capillus, U. lapillus, and U. 
donacopsis as synonyms of Villosa fabalis.
    The snuffbox is a member of the freshwater mussel family Unionidae 
and was described as Truncilla triqueter (Rafinesque 1820, p. 300). The 
species name was later changed to triquetra (Simpson 1900, p. 517), 
from the Latin triquetrous meaning ``having three acute angles,'' a 
reference to the general shape of the female. The type locality is the 
Falls of the Ohio (Ohio River, Louisville, Kentucky) (Parmalee and 
Bogan 1998, p. 108). The synonymy (scientific names used for the 
species) of the snuffbox was summarized by Johnson (1978, pp. 248-249), 
Parmalee and Bogan (1998, p. 108), and Roe (2004, p. 3). This species 
has also been considered a member of the genera Unio, Dysnomia, 
Plagiola, Mya, Margarita, Margaron, and Epioblasma at various times 
since its description. The monotypic subgenus Truncillopsis was created 
for this species (Ortmann and Walker 1922, p. 65). The genus Epioblasma 
was not in common usage until the 1970s (Stansbery 1973, p. 22; 
Stansbery 1976, p. 48; contra Johnson 1978, p. 248), where it currently 
remains (Turgeon et al. 1998, p. 34). Unio triqueter, U. triangularis, 
U. triangularis longisculus, U. triangularis pergibosus, U. cuneatus, 
and U. formosus are recognized as synonyms of E. triquetra. Tricorn 
pearly mussel is another common name for this species (Clarke 1981a, p. 
354).
Life History
    The general biology of the rayed bean and the snuffbox is similar 
to other bivalved mollusks belonging to the family Unionidae. Adults 
are suspension-feeders, spending their entire lives partially or 
completely buried within the substrate (Murray and Leonard 1962, p. 
27). Adults feed on algae, bacteria, detritus, microscopic animals, and 
dissolved organic material (Silverman et al. 1997, p. 1859; Nichols and 
Garling 2000, p. 873; Christian et al. 2004, pp. 108-109; Strayer et 
al. 2004, pp. 430-431). Recent evidence suggests that adult mussels may 
also deposit-feed on particles in the sediment (Raikow and Hamilton 
2001, p. 520). For their first several months, juvenile mussels employ 
foot (pedal) feeding, consuming settled algae and detritus (Yeager et 
al. 1994, p. 221). Unionids have an unusual mode of reproduction. Their 
life cycle includes a brief, obligatory parasitic stage on fish. Eggs 
develop into microscopic larvae called glochidia within special gill 
chambers of the female mussel. The female expels the mature glochidia, 
which must attach to the gills or the fins of an appropriate fish host 
to complete development. Host fish specificity varies among unionids. 
Some species appear to use a single host, while others can transform on 
several host species. Following successful infestation, glochidia 
encyst (enclose in a cyst-like structure) and drop off as newly 
transformed juveniles. For further information on freshwater mussels, 
see Gordon and Layzer (1989, pp. 1-17).
    Mussel biologists know relatively little about the specific life-
history requirements of the rayed bean and the snuffbox. Most mussels, 
including the rayed bean and snuffbox, have separate sexes. The age at 
sexual maturity, which is unknown for the rayed bean and snuffbox, is 
highly variable (0-9 years) among and within species (Haag and Staton 
2003, pp. 2122-2123), and may be sex-dependent (Smith 1979, p. 382). 
Both species are thought to be long-term brooders; rayed bean females 
brood glochidia from May through October (Parmalee and Bogan 1998, p. 
108; Ecological Specialists, Inc. (ESI) 2000, p. 5; Woolnough 2002, p. 
23), and snuffbox brood glochidia from September to May (Ortmann 1912, 
p. 355; 1919, p. 327). Tippecanoe darter (Etheostoma tippecanoe) is the 
only verified host fish for the rayed bean (White et al. 1996, p. 191). 
Other rayed bean hosts are thought to include the greenside darter (E. 
blennioides), rainbow darter (E. caeruleum), mottled sculpin (Cottus 
bairdi), and largemouth bass (Micropterus salmoides) (Woolnough 2002, 
p. 51). Based on inference of closely related species, additional hosts 
may be suitable, including other darter and sculpin species (Jones 
2002, pers. comm.). Juvenile snuffbox have successfully transformed on 
logperch (Percina caprodes), blackside darter (P. maculata), rainbow 
darter, Iowa darter (E. exile), blackspotted topminnow (Fundulus 
olivaceous), mottled sculpin, banded sculpin (C. carolinae), Ozark 
sculpin (C. hypselurus), largemouth bass, and brook stickleback (Culaea 
inconstans) in laboratory tests (Sherman 1994, p. 17; Yeager and Saylor 
1995, p. 3; Hillegass and Hove 1997, p. 25; Barnhart et al. 1998, p. 
34; Hove et al. 2000, p. 30; Sherman Mulcrone 2004, pp. 100-103).
Habitat Characteristics
    The rayed bean is generally known from smaller, headwater creeks, 
but occurrence records exist from larger rivers (Cummings and Mayer 
1992, p. 142; Parmalee and Bogan 1998, p. 244). They are usually found 
in or near shoal or riffle (short, shallow length of stream where the 
stream flows more rapidly) areas, and in the shallow, wave-washed areas 
of glacial lakes, including Lake Erie (West et al. 2000, p. 253). In 
Lake Erie, the species is generally associated with islands in the 
western portion of the lake. Preferred substrates typically include 
gravel and sand. The rayed bean is oftentimes found among vegetation 
(water willow (Justicia americana) and water milfoil (Myriophyllum 
sp.)) in and adjacent to riffles and shoals (Watters 1988b, p. 15; West 
et al. 2000, p. 253). Specimens are typically buried among the roots of 
the vegetation (Parmalee and Bogan 1998, p. 245). Adults and juveniles 
appear to produce byssal threads (thin, protein-based fibers) 
(Woolnough 2002, pp. 99-100), apparently to attach themselves to 
substrate particles.
    The snuffbox is found in small- to medium-sized creeks, to larger 
rivers, and in lakes (Cummings and Mayer 1992, p. 162; Parmalee and 
Bogan 1998, p. 108). The species occurs in swift currents of riffles 
and shoals and wave-washed shores of lakes over gravel and sand with 
occasional cobble and boulders. Individuals generally burrow deep into 
the substrate, except when spawning or attempting to attract a host 
(Parmalee and Bogan 1998, p. 108).
    Strayer (1999a, pp. 471-472) demonstrated in field trials that 
mussels in streams occur chiefly in flow refuges, or relatively stable 
areas that display little movement of particles during flood events. 
Flow refuges conceivably allow relatively immobile mussels to remain in 
the same general location throughout their entire lives. Strayer 
thought that features commonly used in the past to explain the spatial 
patchiness of mussels (water depth, current speed, sediment grain size) 
were poor predictors of where mussels actually occur in streams.
Rayed Bean Historical Distribution
    The rayed bean historically occurred in 115 streams, lakes, and 
some human-made canals in 10 States: Illinois, Indiana, Kentucky, 
Michigan, New York, Ohio, Pennsylvania, Tennessee, Virginia, and West 
Virginia; and Ontario, Canada. The mussel occurred in parts of the 
upper (Lake Michigan

[[Page 8634]]

drainage) and lower Great Lakes systems, and throughout most of the 
Ohio and Tennessee River systems. During historical times, the rayed 
bean was fairly widespread and locally common in many Ohio River system 
streams based on collections made over a several-decade period. The 
species was once fairly common in the Belle, South Branch Thames, 
Detroit, Scioto, Wabash, and Duck Rivers; several tributaries in the 
Scioto system (Olentangy River, and Big Darby and Alum Creeks); and 
Tippecanoe Lake, based on literature and museum records (Call 1900; 
Watters 1994, p. 105; West et al. 2000, p. 251; Badra 2002, pers. 
comm.). The rayed bean was last reported from some streams several 
decades ago (North Branch Clinton, Auglaize, Ohio, West Fork, Beaver, 
Shenango, Mahoning, Mohican, Scioto, Green, Barren, Salamonie, White, 
Big Blue, Tennessee, Holston, South Fork Holston, Nolichucky, Clinch, 
North Fork Clinch, and Powell Rivers; Wolf, Conewango, Oil, Crooked, 
Pymatuning, Mill, Alum, Whetstone, Deer, Lick, and Richland Creeks; and 
Buckeye, Tippecanoe, Winona, and Pike Lakes). The rayed bean population 
in Lake Erie was once considerable (Ohio State University Museum of 
Biological Diversity (OSUM) collections), but has been eliminated by 
the zebra mussel.
Rayed Bean Current Distribution
    Extant populations of the rayed bean are known from 31 streams and 
1 lake in seven States and 1 Canadian province: Indiana (St. Joseph 
River (Fish Creek), Tippecanoe River (Lake Maxinkuckee, Sugar Creek)), 
Michigan (Black River (Mill Creek), Pine River, Belle River, Clinton 
River), New York (Allegheny River (Olean Creek, Cassadaga Creek)), Ohio 
(Swan Creek, Fish Creek, Blanchard River, Tymochtee Creek, Walhonding 
River, Mill Creek, Big Darby Creek, Scioto Brush Creek; Great Miami 
River, Little Miami River (East Fork Little Miami River), Stillwater 
River), Pennsylvania (Allegheny River (French Creek (Le Boeuf Creek, 
Muddy Creek, Cussewago Creek))), Tennessee (Duck River), and West 
Virginia (Elk River); and Ontario, Canada (Sydenham River, Thames 
River).
Rayed Bean Population Estimates and Status
    Based on historical and current data, the rayed bean has declined 
significantly rangewide and is now known only from 31 streams and 1 
lake (down from 115), a 73 percent decline (Table 1). This species has 
also been eliminated from long reaches of former habitat in hundreds of 
miles of the Maumee, Ohio, Wabash, and Tennessee Rivers and from 
numerous stream reaches and their tributaries. In addition, this 
species is no longer known from the States of Illinois, Kentucky, and 
Virginia. The rayed bean was also extirpated from West Virginia, until 
the 2006 reintroduction into the Elk River, and from Tennessee, until 
the 2008 reintroduction into the Duck River (Clayton 2007, pers. comm.; 
Urban 2010, pers. comm.; Moles and Layzer 2009, p. 2).
    In this rule, mussel shell collection records have been classified 
according to the condition of shell material. Fresh dead shells still 
have flesh attached to the valves, they may or may not retain a luster 
to their nacre, and their periostracum is non-peeling, all indicating 
relatively recent death (generally less than 1 year) (Buchanan 1980, p. 
4). Relic shells have lost the luster to their nacre, have peeling or 
absent periostracum, may be brittle or worn, and likely have been dead 
more than a year (Buchanan 1980, pp. 4-5; Zanatta et al. 2002, p. 482). 
Generally, fresh dead shells indicate the continued presence of the 
species at a site (Metcalf 1980, p. 4). The presence of relic shells 
only, along with repeated failure to find live animals or fresh dead 
shells, likely signifies that a population is extirpated (Watters and 
Dunn 1993-94, pp. 253-254). Shells labeled R may originally have been 
reported by collectors as either weathered dead (or weathered dry) or 
subfossil. If no details on shell condition were provided for a record, 
the shell is simply referred to as dead. In this document, a population 
is considered viable if evidence of successful reproduction is 
documented and it has enough individuals to sustain the population at 
its current level for the foreseeable future.

                  Table 1--Rayed Bean Extant Stream Population Summary by Stream of Occurrence
----------------------------------------------------------------------------------------------------------------
                                  Last                          Potential
        Stream (state)          observed     Recruiting         viability      Population size  Population trend
----------------------------------------------------------------------------------------------------------------
Black River (MI).............       2001  Unknown.........  Low.............  Small...........  Unknown.
Mill Creek (MI)..............       2002  Unknown.........  Unknown.........  Small...........  Unknown.
Pine River (MI)..............       2002  Yes.............  High............  Small...........  Declining.
Belle River (MI).............       2010  Unknown.........  Unknown.........  Small...........  Unknown.
Clinton River (MI)...........       2009  Yes.............  Unknown.........  Small...........  Unknown.
Sydenham River (ON)..........       2010  Yes.............  High............  Large...........  Stable.
Thames River (ON)............       2008  Unknown.........  High............  Large...........  Unknown.
Swan Creek (OH)..............       2010  Yes.............  High............  Large...........  Stable.
St. Joseph River (IN)........       1998  Unknown.........  Low.............  Small...........  Declining.
Fish Creek (IN, OH)..........       2009  Unknown.........  Low.............  Small...........  Declining.
Blanchard River (OH).........       2010  Yes.............  High............  Large...........  Unknown.
Tymochtee Creek (OH).........       1996  Unknown.........  Unknown.........  Small...........  Unknown.
Allegheny River (PA, NY).....       2010  Yes.............  High............  Large...........  Stable.
Olean Creek (NY).............       2000  Yes.............  High............  Small...........  Unknown.
Cassadaga Creek (NY).........       1994  Yes.............  Low.............  Small...........  Unknown.
French Creek (PA)............       2005  Yes.............  High............  Large...........  Stable.
Le Boeuf Creek (PA)..........       2006  Unknown.........  Unknown.........  Unknown.........  Unknown.
Muddy Creek (PA).............       2006  Unknown.........  Unknown.........  Unknown.........  Unknown.
Cussewago Creek (PA).........       1991  Unknown.........  Unknown.........  Small...........  Unknown.
Walhonding River (OH)........    1991-95  Unknown.........  Low.............  Small...........  Declining.
Elk River (WV)...............       2010  Unknown           Unknown.........  Small...........  Unknown.
                                           (Reintroduced
                                           in 2006).
Mill Creek (OH)..............       2011  Unknown.........  Unknown.........  Unknown.........  Unknown.
Big Darby Creek (OH).........       2008  Unknown.........  Unknown.........  Small...........  Declining.
Scioto Brush Creek (OH)......       1987  Unknown.........  Unknown.........  Small...........  Unknown.
Great Miami River (OH).......       2010  Unknown.........  Unknown.........  Unknown.........  Unknown.
Little Miami River (OH)......    1990-91  Unknown.........  Unknown.........  Unknown.........  Unknown.

[[Page 8635]]

 
East Fork Little Miami River     1990-91  Unknown.........  Unknown.........  Unknown.........  Unknown.
 (OH).
Stillwater River (OH)........       1987  Unknown.........  Unknown.........  Unknown.........  Unknown.
Tippecanoe River (IN)........       1995  Unknown.........  Low.............  Unknown.........  Declining.
Lake Maxinkuckee (IN)........       1997  Unknown.........  Unknown.........  Unknown.........  Declining.
Sugar Creek (IN).............       1998  Unknown.........  Unknown.........  Unknown.........  Unknown.
Duck River (TN)..............       2008  Unknown           Unknown.........  Small...........  Unknown.
                                           (Reintroduced
                                           in 2008).
----------------------------------------------------------------------------------------------------------------

Upper Great Lakes Sub-Basin

    The rayed bean was not known from the upper Great Lakes sub-basin 
until 1996, when relic specimens were documented from the Pigeon River, 
a tributary to the St. Joseph River that flows into Lake Michigan. No 
extant populations of the rayed bean are currently known from this 
system.

Lower Great Lakes Sub-Basin

    Of the 115 water bodies from which the rayed bean was historically 
recorded, 27 are in the lower Great Lakes system. The species is 
thought to be extant in 12 streams, which are discussed below, but 
historically significant populations have been eliminated from Lake 
Erie and the Detroit River.
    Black River--A tributary of the St. Clair River, linking Lakes 
Huron and St. Clair, the Black River is located in southeastern 
Michigan. Hoeh and Trdan (1985, p. 115) surveyed 17 sites in the Black 
River system, including 12 mainstem sites over approximately 47 miles 
(75 km), but failed to find the rayed bean. The rayed bean was not 
discovered there until the summer of 2001, when a single live 
individual was found in the lower river in the Port Huron State Game 
Area (PHSGA) (Badra 2002, pers. comm.). A survey in 2003 failed to find 
any rayed bean, and two surveys in 2005 found only two valves (Badra 
2008, pers. comm.). An additional survey was performed in 2005 at six 
sites, but no rayed bean were found (Badra 2008, pers. comm.). The 
status of this population cannot be accurately assessed at this time, 
but would appear to be small and of questionable viability (Butler 
2002, p. 8).
    Mill Creek--Mill Creek is a tributary of the Black River, St. Clair 
County, in southeastern Michigan. The rayed bean was discovered in Mill 
Creek in August 2002. Five dead specimens were found approximately 0.5 
miles (mi) (0.8 kilometers (km)) above its confluence with the Black 
River in the PHSGA (Badra 2002, pers. comm.). A Mill Creek site 0.25 mi 
(0.4 km) from the confluence of the Black River was surveyed in 2003 
and 2004, with one rayed bean shell found during each survey (Badra 
2008, pers. comm.). Similar to the population in the Black River, the 
status of this newly discovered population cannot be accurately 
assessed at this time.
    Pine River--Another tributary of the St. Clair River, the Pine 
River is located in southeastern Michigan. The rayed bean was 
apparently not collected in the Pine River until 1982, when specimens 
were found at three sites (Hoeh and Trdan 1985, p. 116). These 
collections included 5 live individuals and 23 fresh dead specimens 
(Badra 2002, pers. comm.). Hoeh and Trdan (1985, p. 116) considered it 
to be ``rare,'' semi-quantitatively defined as occurring at a rate of 
less than one specimen per person-hour sampling effort. In 1997, two 
live individuals were found. The last survey in the Pine River occurred 
in 2002 (Badra 2008, pers. comm.), and one live rayed bean was 
documented (Badra and Goforth 2003, p. 6). Comparing the historical and 
most recent survey resulting, it appears that the species may have 
declined significantly since the 1980s, but it is probably still viable 
in the Pine River.
    Belle River--The Belle River is a third tributary of the St. Clair 
River harboring an extant population of the rayed bean. This species 
was first collected from the Belle River in 1965, when 17 fresh dead 
specimens were collected (OSUM 1965:0106). The same site was revisited 
in 1978, but only one fresh dead shell is represented in OSUM 
1978:0013. Since that time, live individuals or fresh dead specimens 
were found in 1983 and 1992, while only relic shells were found in 1994 
(Badra 2008, pers. comm.). During summer 2002 sampling, single live 
specimens were found at two new sites in the Belle River, with four and 
two fresh dead specimens, respectively, also found at these sites 
(Badra 2008, pers. comm.). In 2010, five live individuals were found at 
the same two sites sampled in 2002 (Zanatta 2011, pers. comm.). These 
two sites are about 2 miles (3.2 km) apart in the lower portion of the 
river. The status of the Belle River population is still not well 
known, but appears to be small and restricted to a short reach in the 
lower river.
    Clinton River--The rayed bean was first recorded from the Clinton 
River in 1933 (Badra 2008, pers. comm.). The mussel fauna in the entire 
mainstem of the Clinton River downstream of Pontiac, Michigan, was 
apparently wiped out by pollution between 1933 and 1977 (Strayer 1980, 
p. 147). In 1992, Trdan and Hoeh (1993, p. 102) found 26 live 
individuals using a suction dredge from a bridge site slated for 
widening, where Strayer (1980, p. 146) previously found only relic 
shells. The rayed bean represented 1.2 percent relative abundance of 
the 10 species collected at the site (Trdan and Hoeh 1993, p. 102). The 
population in the Clinton River is probably viable but currently 
restricted to about 3 mi (4.8 km) of stream in the western suburbs of 
Pontiac (Butler 2002, p. 9). Zanatta (2011, pers. comm.) found one live 
rayed bean in 2009. The rayed bean's long-term viability appears to be 
precarious in the Clinton River.
    Sydenham River--The rayed bean in the Sydenham River represents one 
of the largest rayed bean populations remaining. West et al. (2000, pp. 
252-253) presented a highly detailed collection history of the rayed 
bean in the Sydenham River. The rayed bean is currently thought to 
exist in an approximately 75-mi (120-km) reach of the middle Sydenham, 
from the general vicinity of Napier, Ontario, downstream to Dawn Mills. 
The species appears to be most abundant in the lower half of this river 
reach. Although the range has remained relatively consistent over time, 
abundance data at repeatedly sampled sites from the 1960s to the late 
1990s indicate a general decline of the rayed bean. Based on the range 
of sizes and roughly equal number of specimens in various size classes 
of the live and fresh dead material they gathered, West et al. (2000, 
p. 256) considered the population to be ``healthy'' and ``reproducing'' 
(recruiting). Data from sampling in 2001 show evidence of

[[Page 8636]]

recruitment and variable size classes for both sexes from most of the 
sites (Woolnough 2002, p. 50). Based on this data, the rayed bean 
population in the Sydenham River is doing considerably better than West 
et al. (2000, pp. 252-253) suggested. Woolnough and Morris (2009, p. 
19) estimate that there are 1.5 million mature rayed bean in the 
Sydenham River living in the 38-mile (61-km) stretch between Napier 
Road near Alvinston, Ontario, and Dawn Mills, Ontario.
    Thames River--The Thames River flows west through southwestern 
Ontario. The rayed bean was historically known from only the south 
branch until 2008, when it was discovered in the north branch. In July 
2008, six gravid (gills full of glochidia) females were collected at 
two north branch sites (Woolnough 2008, pers. comm.). In September 
2008, four live females and two live males were collected at two 
different north branch sites (Woolnough 2008, pers. comm.). All of 
these individuals were collected within a 4.5-mi (7.2-km) reach of the 
river (Woolnough 2008, pers. comm.). Woolnough and Morris (2009, p. 19) 
estimate that there are 4,300 mature rayed bean in the Thames River.
    Maumee River System--The Maumee River system, which flows into the 
western end of Lake Erie, was once a major center of distribution of 
the rayed bean. The species was historically known from eight streams 
in the system in addition to the mainstem Maumee. Further, an 
additional population was discovered in the system in 2005 in Swan 
Creek.
    Swan Creek--Swan Creek is a tributary of the lower Maumee River in 
northwestern Ohio. This population was discovered in 2005. Surveys 
conducted in 2006 and 2007 found that the Swan Creek population is 
limited to about 3 river mi (5 river km) between river mile (RM) 18.3 
and 15.3 (Grabarkiewicz 2008, p. 11). The rayed bean was the fourth 
most abundant unionid present within the 2006-2008 sample area, 
reaching densities of eight individuals per square meter in some areas 
and comprising about 14.1 percent of the total mussel community 
(Grabarkiewicz 2008, p. 10). The rayed bean population in Swan Creek is 
viable and, although limited to a short reach, may be one of the most 
robust remaining populations.
    St. Joseph River--The St. Joseph River is one of the two major 
headwater tributaries to the Maumee, with a drainage area in 
southeastern Michigan, northwestern Ohio, and northeastern Indiana. The 
mainstem flows in a southwesterly direction to its confluence with the 
St. Mary's River to form the Maumee in Ft. Wayne, Indiana. The rayed 
bean was historically known from numerous sites on the river, but now 
apparently persists only at a couple of sites in the lower St. Joseph 
River in Allen and DeKalb Counties, Indiana (Watters 1988b, p. 15; 
1998, Appendix C); a few fresh dead specimens were found in both 
studies, but no live individuals were found. Grabarkiewicz and Crail 
(2008, p. 13) surveyed six sites on the West Branch St. Joseph River in 
2007, but did not encounter any rayed bean.
    Fish Creek--A tributary of the St. Joseph River that begins in 
Ohio, Fish Creek flows west, then south through Indiana, then 
eventually east into Ohio before joining the St. Joseph River at 
Edgerton. The rayed bean persists in Williams County, Ohio, and 
possibly DeKalb County, Indiana. Based on the appearance of 2 live 
individuals and fresh dead shells, it inhabits the lower 10 mi (16.1 
km) or less of the stream (Watters 1988b, p. 18; Grabarkiewicz 2009, 
pers. comm.). Watters (1988b, p. ii) considered Fish Creek to be ``the 
most pristine tributary of the St. Joseph system.'' A major diesel fuel 
spill from a ruptured pipeline in DeKalb County in 1993 resulted in a 
mussel kill in the lower portion of the stream (Sparks et al. 1999, p. 
12). It is not known if the rayed bean was affected by the spill. 
Surveys in 2004 (at 64 qualitative sites) and 2005 (at 11 quantitative 
sites) failed to detect the species (Brady et al. 2004, p. 2; 2005, p. 
3). However, Grabarkiewicz (2009, pers. comm.) reported finding two 
live and three fresh dead rayed bean in 2005, at the County Road 3 
bridge in Ohio. In 2009, two fresh dead rayed bean were found in lower 
Fish Creek in Ohio (Boyer 2009, pers. obs.). The viability and status 
of this population are uncertain (Fisher 2008, pers. comm.).
    Blanchard River--The Blanchard River is a tributary of the Auglaize 
River in the Maumee River system, in northwestern Ohio. First 
discovered in 1946, this population is one of the largest of the rayed 
bean rangewide. The rayed bean in the Blanchard River is restricted to 
25-30 river mi (40-48 river km) in the upper portion of the stream in 
Hardin and Hancock Counties upstream of Findley (Hoggarth et al. 2000, 
p. 22). Hoggarth et al. (2000, p. 23) reported the rayed bean to be the 
fourth most common species in the drainage. Grabarkiewicz (2010, pers. 
comm.) found live individuals, including a juvenile, at six sites 
sampled in 2010. The population is considered to be viable.
    Tymochtee Creek--Tymochtee Creek is a tributary to the upper 
Sandusky River in north-central Ohio, which flows into the southwestern 
portion of Lake Erie. The rayed bean is known from three sites in a 
reach of stream in Wyandot County and was first collected in 1970. All 
collections of the rayed bean have been small, with not more than five 
fresh dead shells found in any one collection effort. The last record 
is for 1996, when a pair and three unpaired valves were collected. The 
condition of at least one of the valves indicated that the rayed bean 
is probably still extant in the stream, although no live individuals 
were observed (Athearn 2002, pers. comm.). The rayed bean status in 
Tymochtee Creek is, therefore, currently unknown.

Ohio River System

    The rayed bean was historically known from the Ohio River in the 
vicinity of Cincinnati, Ohio, downstream to the Illinois portion of the 
river. It undoubtedly occurred elsewhere in the upper mainstem. Few 
historical records are known (mostly circa 1900), and no recent 
collections have been made, indicating that it became extirpated there 
decades ago. It was historically known from 74 streams, canals, and 
lakes in the system, representing roughly two-thirds of its total 
range. Ortmann (1925, p. 354) considered the rayed bean to be 
``abundant in small streams'' in the Ohio River system. Currently, only 
18 streams and a lake are thought to have extant rayed bean populations 
in the system.
    Allegheny River System--Nine streams and Chautauqua Lake 
historically harbored rayed bean populations in the Allegheny River 
system. Currently, the rayed bean is found in half of these water 
bodies, but in good numbers in two streams (Allegheny River and French 
Creek) in this drainage.
    Allegheny River--The Allegheny River drains northwestern 
Pennsylvania and western New York, joining the Monongahela River at 
Pittsburgh, Pennsylvania, to form the Ohio River. Ortmann (1909a, p. 
179; 1919, p. 262) was the first to report the rayed bean from the 
Allegheny. The population once stretched from Cataraugus County, New 
York, to Armstrong County, Pennsylvania. Based on historical 
collections, it appears that the rayed bean is more abundant now than 
it was historically in the Allegheny River. This may indicate that the 
rayed bean population in the Allegheny has expanded in the past 100 
years. Many streams in western Pennsylvania have improved water quality 
since Ortmann's time, when he reported on the

[[Page 8637]]

wholesale destruction of mussels in several streams (Ortmann 1909b, pp. 
11-12). The species currently occurs in Pennsylvania downstream of 
Allegheny (Kinzua) Reservoir in Warren County to the pool of Lock and 
Dam 6 in northern Armstrong County, a distance of over 100 river mi 
(161 river km) (Villella Bumgardner 2008, pers. comm.). The Allegheny 
population is viable and one of the most important remaining rangewide 
today.
    Olean Creek--Olean Creek is a tributary of the Allegheny River in 
western New York. A small population of the rayed bean is known from 
the lower portions of the stream. Strayer et al. (1991, p. 67) reported 
the rayed bean from three sites during 1987-90 sampling, although just 
one live individual was located with relic shells from the other two 
sites. Only relic shells were found in Olean Creek in 1994, but three 
live individuals were found in 2000, at the proposed construction site 
of the City of Olean Water Treatment Plant (ESI 2000, p. 8). Collected 
only during their quantitative sampling effort, the rayed bean 
represented a relative abundance of 11.5 percent of the seven live 
species sampled. The rayed bean age distribution of these specimens 
also indicates recent recruitment into the population (ESI 2000, p. 9). 
Relic specimens are now known from an 8-mi (13-km) reach of stream, 
with live individuals known from less than 1.5 mi (2.4 km) of the lower 
creek. The Olean Creek population appears viable, but is small and 
tenuous (Butler 2008, pers. comm.)
    Cassadaga Creek--Cassadaga Creek is a tributary of Conewango Creek 
in the Allegheny River system, in western New York. A small population 
of the rayed bean is known from a single riffle (Ross Mills) in the 
lower creek north of Jamestown. Four live specimens were found in 1994 
(Strayer 1995). Muskrat middens (a pile of shells) collected during the 
winter of 2002 produced 38 fresh dead specimens with a size range of 
0.8-1.7 in (2.0-4.3 cm) (Clapsadl 2002, pers. comm.). Although the 
rayed bean is not known from other sites in the stream, it appears to 
be viable at this site.
    French Creek--French Creek is a major tributary of the middle 
Allegheny River, in western New York and northwestern Pennsylvania. One 
of the largest rayed bean populations known, it is found in much of the 
lower portions of the stream in four Pennsylvania counties (the species 
is not known from the New York portion of stream). Ortmann (1909a, p. 
188; 1919, p. 264) reported the species from two counties, Crawford and 
Venango. Not until circa 1970 did the population become more thoroughly 
known, with museum lot sizes indicating sizable populations at several 
sites, particularly in the lower reaches of the stream. Recent 
collections indicate that population levels remain high with the rayed 
bean occurring throughout the mainstem (Villella Bumgardner 2002, pers. 
comm.; Smith and Crabtree 2005, pp. 15-17; Enviroscience 2006, p. 5).
    Le Boeuf Creek--Le Boeuf Creek is a small western tributary of 
upper French Creek, flowing in a southerly direction just west of West 
Branch French Creek in Erie County, Pennsylvania. A total of five live 
individuals were collected at two out of five sites during a 2006 
survey (Smith et al. 2009, pp. 68-76; Welte 2011, pers. comm.). No 
other information is available on the status of this population.
    Muddy Creek--Muddy Creek is an eastern tributary of upper French 
Creek in Crawford County, Pennsylvania. The rayed bean was not 
discovered until the summer of 2006. Live and fresh dead rayed bean 
were reported from 2 of 20 lower river sites (Mohler et al. 2006, pp. 
581-582). No live juveniles were found during the 2006 survey (Mohler 
et al. 2006, p. 576). No other information is available on the status 
of this population.
    Cussewago Creek--Cussewago Creek is a tributary of lower French 
Creek, with its confluence at Meadville, Crawford County, Pennsylvania. 
A small population was reported in 1991 from Cussewago Creek (Proch 
2001, pers. comm.). The rayed bean is thought to persist in the stream, 
but its current status is unknown.
    Walhonding River--The Walhonding River is a tributary of the upper 
Muskingum River system, in central Ohio, forming the latter river at 
its confluence with the Tuscarawas River at Coschocton. Small numbers 
of rayed bean shells are represented in OSUM collections from the 1960s 
and 1970s. During 1991-93, Hoggarth (1995-96, p. 161) discovered one 
live individual and one fresh dead specimen at one site, while four 
relic specimens were found at three other sites. A small rayed bean 
population is thought to remain in the Walhonding River; its status is 
unknown, but is deemed highly tenuous, given the small population size. 
The population is probably nearing extirpation (Hoggarth 2008a, pers. 
comm.).
    Elk River--The Elk River is a major 181-river-mi (291-river-km) 
tributary in the lower Kanawha River system draining central West 
Virginia and flowing west to the Kanawaha River at Charleston. The 
rayed bean was extirpated in the Elk River sometime in the 1990s. In 
2006 and 2007, approximately 600 adults were reintroduced into the Elk 
River above Clendenin. In 2008, an effort was made to monitor the 
reintroduction. A 30-minute search yielded two live individuals, but 
efforts were discontinued due to high water and excessive habitat 
disturbance caused by the search effort (Clayton 2008, pers. comm.). In 
2010, none of the individuals released in 2006 was found, but an 
additional 200 individuals were released (Clayton 2010, pers. comm.). 
The translocated adults are thought to persist in the stream, but it is 
unknown if this new population is reproducing.
    Scioto River system--The Scioto River system, in central and south-
central Ohio, is a major northern tributary of the Ohio River. A 
historically large metapopulation of the rayed bean occupied at least 
11 streams, the Ohio and Erie Canal, and Buckeye Lake. Sizable 
populations were noted in at least the Olentangy River, and Alum and 
Big Darby Creeks, based on OSUM collections primarily from the 1960s. A 
series of system reservoirs, mostly north of Columbus, reduced habitat 
and contributed to the elimination of some populations in several 
streams (Alum, Big Walnut, and Deer Creeks; Olentangy and Scioto 
Rivers). The location of the Columbus Metropolitan Area in the heart of 
the watershed has also taken a major toll on the species. The 
historical Scioto rayed bean metapopulation has since been decimated by 
anthropogenic factors. Currently, remnant populations are known only 
from Mill Creek, Big Darby Creek, and Scioto Brush Creek.
    Mill Creek--Mill Creek is a tributary of the Scioto River in 
central Ohio that joins the Scioto River at the O'Shaughnessy Reservoir 
northwest of the City of Columbus. In 2004, seven fresh dead specimens 
were found during a survey in the City of Marysville (Hoggarth 2005, p. 
7). In 2007, Hoggarth (2007a, pp. 5-6) found two live rayed bean at the 
same site and one live individual at an additional site. No other 
information is available on the status of this population.
    Big Darby Creek--Big Darby Creek is one of the major tributaries 
draining the northwestern portion of the Scioto River system in central 
Ohio. A sizable rayed bean population was noted in Big Darby Creek from 
OSUM collections, primarily from the 1960s. Watters (1994, p. 105) 
reported finding a few fresh dead specimens in 1986, but none in 1990, 
and indicated that the rayed bean was probably extirpated from Big 
Darby Creek. In 2006, one live individual was

[[Page 8638]]

found at the U.S. Highway 42 bridge replacement project site (Hoggarth 
2006, p. 6). This individual was relocated to a site upstream out of 
the impact zone of the bridge project, and nine additional live 
individuals were subsequently found at the relocation site (Hoggarth 
2006, p. 6). In 2007, three live rayed bean were found at the 
relocation site (Hoggarth 2007b, p. 9). Hoggarth (2008b, pers. comm.) 
visited the same relocation site in 2008, and reported finding 
``numerous living specimens'' of the rayed bean. The status of this 
population cannot be accurately assessed at this time, but would appear 
to be small and of questionable viability.
    Scioto Brush Creek--Scioto Brush Creek is a small western tributary 
of the lower Scioto River in Scioto County, south-central Ohio. Watters 
(1988a, p. 45) discovered the rayed bean in this stream in 1987, 
reporting two fresh dead and two relic specimens from a site, and a 
relic specimen from a second site among the 20 sites he collected. This 
population's current status is uncertain.
    Great Miami River - The Great Miami River is a major northern 
tributary of the Ohio River in southwestern Ohio that originates from 
Indian Lake in west-central Ohio and flows into the Ohio River west of 
Cincinnati. The occurrence of the rayed bean in the Great Miami River 
was discovered in August 2009, during a mussel survey for a bridge 
project in Logan County, Ohio. Only one individual was documented, a 
male approximately 7 to 8 years of age (Hoggarth 2009, pers. comm.). 
The following year, Hoggarth (2010, p. 5) found a juvenile rayed bean. 
The status of this newly discovered population is not known.
    Little Miami River--The Little Miami River is a northern tributary 
of the Ohio River in southwestern Ohio, flowing into the latter at the 
eastern fringe of the Cincinnati metropolitan area. Hoggarth (1992, p. 
248) surveyed over 100 sites in the entire system. He found one live 
individual at a site in Warren County and possibly a subfossil shell at 
another site, although there is contradictory data in his paper (Butler 
2002, p. 17). The latter site may have been the same as that reported 
for a pre-1863 record (Hoggarth 1992, p. 265). The rayed bean appears 
to be very rare in the Little Miami, having been found extant at only 1 
of 46 mainstem sites. Hoggarth (1992, p. 267) highlighted the ``fragile 
nature'' of the extant mussel community in the system, while noting 
that localized reaches of the Little Miami were ``severely impacted.'' 
The species' status in the river is uncertain, but apparently very 
tenuous and probably headed toward extirpation (Butler 2002, p. 17).
    East Fork Little Miami River--The East Fork Little Miami River is 
an eastern tributary of the lower Little Miami River, with its 
confluence at the eastern fringe of the Cincinnati metropolitan area. 
According to OSUM records, eight fresh dead specimens were reported 
from a site in eastern Clermont County in 1973. Hoggarth (1992, p. 265) 
reported one live, three fresh dead, and one relic rayed bean from 
three sites in a 7-river-mi (11-river-km) stretch of the stream in 
western Clermont and adjacent Brown County (including the 1973 site). 
Harsha Reservoir on the East Fork destroyed several miles of potential 
stream habitat for the rayed bean a few miles downstream of the extant 
population. The status of the rayed bean in the river is uncertain, but 
probably of doubtful persistence (Butler 2002, p. 17).
    Stillwater River--The Stillwater River is a western tributary of 
the middle Great Miami River in southwestern Ohio. The rayed bean is 
known from two specimens, one fresh dead and one relic, collected in 
1987 at two sites spanning the Miami-Montgomery County line (OSUM 
records). Both sites occur in the footprint of Englewood Reservoir 
(constructed circa 1920), which serves as a retarding basin (a 
constructed empty lake used to absorb and contain flooding in periods 
of high rain) that is normally a free-flowing river except in times of 
flood, therefore continuing to provide riverine habitat that is 
normally destroyed by permanently impounded reservoirs. The rayed bean 
in the Stillwater River may be extant, but its status is currently 
unknown and considered highly imperiled (Butler 2002, p. 17).
    Tippecanoe River--The Tippecanoe River is a large northern 
tributary of the middle Wabash River in north-central Indiana. The 
first records for the rayed bean date to circa 1900 (Daniels 1903, p. 
646). Historically, this species was known from numerous sites in six 
counties in the Tippecanoe River. A total of 12 fresh dead specimens 
from 5 of 30 sites were found when sampled in 1992. The rayed bean ``is 
apparently on the decline'' in the river (ESI 1993, p. 87). The 
Tippecanoe rayed bean population was thought to be recruiting by Fisher 
(2008, pers. comm.), but appears tenuous and its long-term viability is 
questionable.
    Lake Maxinkuckee--Lake Maxinkuckee is a glacial lake in the 
headwaters of the Tippecanoe River in north-central Indiana. The rayed 
bean has been known from the lake for more than a century (Blatchley 
1901). A 1997 OSUM record included seven fresh dead specimens collected 
at its outlet to the Tippecanoe River. Fisher (2002, pers. comm.), who 
made the 1997 OSUM collection, noted that many native mussels had zebra 
mussels attached to their valves that were apparently contributing to 
their mortality. The status of the rayed bean in Lake Maxinkuckee is, 
therefore, highly tenuous, and its long-term persistence questionable.
    Sugar Creek--Sugar Creek is a tributary of the East Fork White 
River, in the lower Wabash River system in south-central Indiana. A 
rayed bean population was first reported there in 1930 (Butler 2002, p. 
19). Harmon (1992, p. 33) sampled 27 mainstem and 16 tributary sites, 
finding fresh dead specimens at 3 mainstem sites and relic specimens 
from 2 other sites. The sites with fresh dead material were found in 
the lowermost 6 mi (9.7 km) of stream. The status and viability of this 
tenuous population is uncertain (Fisher 2008, pers. comm.).

Tennessee River System

    Historically, the rayed bean was known from the Tennessee River and 
12 of its tributary streams. Ortmann (1924, p. 55) reported that the 
rayed bean had a ``rather irregular distribution''; however, museum 
lots show that it was fairly common in some streams (North Fork Clinch, 
Duck Rivers). The last live rayed bean records from the system, with 
the exception of the Duck River, were from the 1960s or earlier. The 
species persisted in the Duck until the early 1980s. Prior to the 2008 
reintroduction into the Duck River, intensive sampling in the Duck 
watershed had failed to locate even a relic shell of the rayed bean 
(Ahlstedt et al. 2004, p. 29). Tributaries in this system have been 
extensively sampled over the past 25 years.
    Duck River--The Duck River is the downstream-most large tributary 
of the Tennessee River draining south-central Tennessee and flowing 285 
river miles (459 river km) west to its confluence near the head of 
Kentucky Reservoir. The rayed bean was considered to be extirpated from 
the river until a reintroduction took place in September 2008. A total 
of 969 adults were collected from the Allegheny River at East Brady, 
Pennsylvania, in 2008 (Welte 2011, pers. comm.). Following quarantine 
and retention of several individuals for propagation, a total of 681 
rayed bean were translocated to the Duck River near Lillard Mill, 
Tennessee (Urban 2010, pers. comm.; Moles and Layzer 2009, pp. 2-3; 
Welte 2011, pers. comm.). Although the rayed bean was extirpated from 
the Duck River about 25 years ago, major improvements in water

[[Page 8639]]

quality and physical habitat conditions have occurred in the past 15 
years. In response to these improvements, recruitment of nearly all 
extant mussel species has been documented and suggests that 
reintroduction of the rayed bean might be successful (Anderson 2008, 
pers. comm.). The status of the reintroduced population was assessed in 
2009. Rayed bean survival rates from three plots and downstream 
dispersal areas ranged from 38 to 62 percent (Moles and Layzer 2009, 
pp. 4-7).

Summary of Rayed Bean Population Estimates and Status

    The information presented in this final rule indicates that the 
rayed bean has experienced a significant reduction in range and most of 
its populations are disjunct, isolated, and, with few exceptions, 
appear to be declining (West et al. 2000, p. 251). The extirpation of 
this species from over 80 streams and other water bodies within its 
historical range indicates that substantial population losses have 
occurred. Relatively few streams are thought to harbor sizable viable 
populations (Sydenham, Blanchard, and Allegheny Rivers, and French and 
Swan Creeks). Small population size and restricted stream reaches of 
current occurrence are a real threat to the rayed bean due to the 
negative genetic aspects associated with small, geographically isolated 
populations. This can be especially true for a species, like the rayed 
bean, that was historically widespread and had population connectivity 
among mainstem rivers and multiple tributaries. The current 
distribution, abundance, and trend information illustrates that the 
rayed bean is imperiled.

Snuffbox Historical Distribution

    The snuffbox historically occurred in 210 streams and lakes in 18 
States and 1 Canadian province: Alabama, Arkansas, Illinois, Indiana, 
Iowa, Kansas, Kentucky, Michigan, Minnesota, Mississippi, Missouri, New 
York, Ohio, Pennsylvania, Tennessee, Virginia, West Virginia, and 
Wisconsin; and Ontario, Canada. The major watersheds of historical 
streams and lakes of occurrence include the upper Great Lakes sub-basin 
(Lake Michigan drainage), lower Great Lakes sub-basin (Lakes Huron, 
Erie, and Ontario drainages), upper Mississippi River sub-basin, lower 
Missouri River system, Ohio River system, Cumberland River system, 
Tennessee River system, lower Mississippi River sub-basin, and White 
River system.

Snuffbox Current Distribution

    Extant populations of the snuffbox are known from 79 streams in 14 
States and 1 Canadian province: Alabama (Tennessee River, Paint Rock 
River, and Elk River), Arkansas (Buffalo River, Spring River, and 
Strawberry River), Illinois (Kankakee River and Embarras River), 
Indiana (Pigeon River, Salamonie River, Tippecanoe River, Sugar Creek, 
Buck Creek, Muscatatuck River, and Graham Creek), Kentucky (Tygarts 
Creek, Kinniconick Creek, Licking River, Slate Creek, Middle Fork 
Kentucky River, Red Bird River, Red River, Rolling Fork Salt River, 
Green River, and Buck Creek), Michigan (Grand River, Flat River, Maple 
River, Pine River, Belle River, Clinton River, Huron River, Davis 
Creek, South Ore Creek, and Portage River), Minnesota (Mississippi 
River, St. Croix River), Missouri (Meramec River, Bourbeuse River, St. 
Francis River, and Black River), Ohio (Grand River, Ohio River, 
Muskingum River, Walhonding River, Killbuck Creek, Olentangy River, Big 
Darby Creek, Little Darby Creek, Salt Creek, Scioto Brush Creek, South 
Fork Scioto Brush Creek, Little Miami River, and Stillwater River), 
Pennsylvania (Allegheny River, French Creek, West Branch French Creek, 
Le Boeuf Creek, Woodcock Creek, Muddy Creek, Conneaut Outlet, Little 
Mahoning Creek, Shenango River, and Little Shenango River), Tennessee 
(Clinch River, Powell River, Elk River, and Duck River), Virginia 
(Clinch River and Powell River), West Virginia (Ohio River, Middle 
Island Creek, McElroy Creek, Little Kanawha River, Hughes River, North 
Fork Hughes River, and Elk River), and Wisconsin (St. Croix River, Wolf 
River, Embarrass River, Little Wolf River, and Willow Creek); and 
Ontario, Canada (Ausable River and Sydenham River). It is probable that 
the species persists in some of the 132 streams or lakes where it is 
now considered extirpated (Butler 2007, p. 16); however, if extant, 
these populations are likely to be small and not viable.

Snuffbox Population Estimates and Status

    Based on historical and current data, the snuffbox has declined 
significantly rangewide and is now known only from 79 streams (down 
from 210 historically), representing a 62 percent decline in occupied 
streams (Table 2). Because multiple streams may comprise a single 
snuffbox population (French Creek system), the actual number of extant 
populations is fewer than 79. Extant populations, with few exceptions, 
are highly fragmented and restricted to short reaches. Available 
records indicate that 25 of 79, or 32 percent, of streams considered to 
harbor extant populations of the snuffbox are represented by only one 
or two recent live or fresh dead individuals (Little Wolf, Maple, 
Pigeon, Kankakee, Meramec, Ohio, Muskingum, Olentangy, Stillwater, 
Hughes, Green, Powell, Duck, and Black Rivers; and Little Mahoning, 
Woodcock, McElroy, Big Darby, Little Darby, Salt, South Fork Scioto 
Brush, Slate, and Buck (Indiana), Graham, and Buck (Kentucky) Creeks.

                                       Table 2--Snuffbox Extant Stream Population Summary by Stream of Occurrence
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                     Last
         Stream (state)            observed       Recruiting       Potential  viability     Population size      Population trend      Status  category
--------------------------------------------------------------------------------------------------------------------------------------------------------
Wolf River (WI).................       2010  Yes.................  High................  Large...............  Declining...........  Stronghold.
Embarrass River (WI)............       2006  Unknown.............  Unknown.............  Small...............  Unknown.............  Marginal.
Little Wolf River (WI)..........       2004  Unknown.............  Unknown.............  Small...............  Unknown.............  Marginal.
Willow Creek (WI)...............       2001  Unknown.............  Unknown.............  Small...............  Unknown.............  Marginal.
Grand River (MI)................       2002  Yes.................  High................  Medium..............  Unknown.............  Significant.
Flat River (MI).................       2010  Yes.................  High................  Medium..............  Unknown.............  Significant.
Maple River (MI)................       2001  Unknown.............  Unknown.............  Small...............  Unknown.............  Marginal.
Pine River (MI).................       2002  Unknown.............  Low.................  Small...............  Stable..............  Marginal.
Belle River (MI)................       2010  Yes.................  High................  Small...............  Unknown.............  Significant.
Clinton River (MI)..............       2009  Yes.................  High................  Large...............  Declining...........  Significant.
Huron River (MI)................       2008  Unknown.............  Low.................  Medium..............  Unknown.............  Significant.
Davis Creek (MI)................       2008  Yes.................  High................  Medium..............  Unknown.............  Significant.
South Ore Creek (MI)............       1999  Yes.................  High................  Small...............  Unknown.............  Significant.
Portage River (MI)..............       1998  Yes.................  High................  Medium..............  Unknown.............  Significant.
Grand River (OH)................       2006  Yes.................  High................  Medium..............  Unknown.............  Significant.

[[Page 8640]]

 
Upper Mississippi River (MN)....       2010  No..................  Unknown.............  Unknown.............  Unknown.............  Marginal.
St. Croix River (MN and WI).....       2010  Yes.................  High................  Large...............  Declining...........  Significant.
Kankakee River (IL).............       1991  Unknown.............  Unknown.............  Small...............  Unknown.............  Marginal.
Meramec River (MO)..............       1997  Unknown.............  Unknown.............  Small...............  Declining...........  Marginal.
Bourbeuse River (MO)............       2006  Yes.................  High................  Large...............  Improving...........  Stronghold.
Ohio River (OH, WV).............       2001  Unknown.............  Low.................  Small...............  Unknown.............  Marginal.
Muskingum River (OH)............       2005  Unknown.............  Unknown.............  Small...............  Unknown.............  Marginal.
Walhonding River (OH)...........       1991  Unknown.............  Unknown.............  Small...............  Declining...........  Significant.
Killbuck Creek (OH).............       2010  Unknown.............  Unknown.............  Small...............  Declining...........  Marginal.
Olentangy River (OH)............       1989  Unknown.............  Unknown.............  Small...............  Declining...........  Marginal.
Big Darby Creek (OH)............       2008  Unknown.............  Unknown.............  Small...............  Declining...........  Marginal.
Little Darby Creek (OH).........       1999  Unknown.............  Unknown.............  Small...............  Declining...........  Marginal.
Salt Creek (OH).................       1987  Unknown.............  Unknown.............  Small...............  Unknown.............  Marginal.
Scioto Brush Creek (OH).........       1987  Unknown.............  Unknown.............  Small...............  Unknown.............  Marginal.
South Fork Scioto Brush Creek          1987  Unknown.............  Unknown.............  Small...............  Unknown.............  Marginal.
 (OH).
Little Miami River (OH).........       1991  Unknown.............  Unknown.............  Small...............  Unknown.............  Marginal.
Stillwater River (OH)...........       1987  Unknown.............  Unknown.............  Small...............  Unknown.............  Marginal.
Pigeon River (IN)...............       1998  Unknown.............  Unknown.............  Small...............  Unknown.............  Marginal.
Salamonie River (IN)............       2004  Yes.................  Low.................  Small...............  Unknown.............  Significant.
Tippecanoe River (IN)...........       2003  Unknown.............  Unknown.............  Small...............  Declining...........  Marginal.
Embarras River (IL).............       2008  Yes.................  Low.................  Small...............  Declining...........  Significant.
Sugar Creek (IN)................       1990  Unknown.............  Unknown.............  Small...............  Declining...........  Marginal.
Buck Creek (IN).................       1990  Unknown.............  Unknown.............  Small...............  Unknown.............  Marginal.
Muscatatuck River (IN)..........       1988  Unknown.............  Unknown.............  Small...............  Unknown.............  Marginal.
Graham Creek (IN)...............       1990  Unknown.............  Unknown.............  Small...............  Declining...........  Marginal.
St. Francis River (MO)..........       2006  Yes.................  High................  Medium..............  Stable..............  Significant.
Black River (MO)................       2002  Yes.................  Low.................  Small...............  Unknown.............  Significant.
Tygarts Creek (KY)..............       1995  Unknown.............  Unknown.............  Small...............  Declining...........  Marginal.
Kinniconick Creek (KY)..........       2005  Unknown.............  Low.................  Small...............  Declining...........  Marginal.
Licking River (KY)..............       2006  Unknown.............  Low.................  Small...............  Unknown.............  Marginal.
Slate Creek (KY)................       1992  Unknown.............  Unknown.............  Small...............  Declining...........  Marginal.
Middle Fork Kentucky River (KY).       1997  Unknown.............  Unknown.............  Small...............  Unknown.............  Marginal.
Red Bird River (KY).............       1995  Unknown.............  Unknown.............  Small...............  Unknown.............  Marginal.
Red River (KY)..................      ~2002  Unknown.............  Unknown.............  Small...............  Unknown.............  Significant.
Rolling Fork Salt River (KY)....      ~2005  Unknown.............  Unknown.............  Small...............  Unknown.............  Marginal.
Green River (KY)................       1989  Unknown.............  Unknown.............  Small...............  Declining...........  Marginal.
Buck Creek (KY).................    1987-90  Unknown.............  Unknown.............  Small...............  Declining...........  Marginal.
Clinch River (TN and VA)........       2006  Yes.................  High................  Large...............  Stable or Declining.  Stronghold.
Powell River (TN and VA)........       2008  Unknown.............  Unknown.............  Small...............  Declining...........  Marginal.
Tennessee River (AL)............       2006  Unknown.............  Unknown.............  Small...............  Unknown.............  Marginal.
Paint Rock River (AL)...........       2008  Yes.................  High................  Large...............  Improving...........  Stronghold.
Elk River (TN and AL)...........       2007  Yes.................  Low.................  Small...............  Stable..............  Significant.
Duck River (TN).................       2001  Unknown.............  Unknown.............  Small...............  Unknown.............  Marginal.
Buffalo River (AR)..............       2006  Unknown.............  Unknown.............  Small...............  Unknown.............  Marginal.
Spring River (AR)...............       2005  Unknown.............  Low.................  Medium..............  Unknown.............  Significant.
Strawberry River (AR)...........       1997  Unknown.............  Unknown.............  Small...............  Unknown.............  Marginal.
Allegheny River (PA)............       2001  Unknown.............  Unknown.............  Small...............  Unknown.............  Marginal.
French Creek (PA)...............       2008  Yes.................  High................  Large...............  Stable..............  Stronghold.
West Branch French Creek (PA)...       2008  Unknown.............  Unknown.............  Small...............  Unknown.............  Marginal.
Le Boeuf Creek (PA).............       2006  Yes.................  Low.................  Small...............  Unknown.............  Marginal.
Woodcock Creek (PA).............       2007  Unknown.............  Unknown.............  Small...............  Unknown.............  Marginal.
Muddy Creek (PA)................       2008  Yes.................  Low.................  Medium..............  Unknown.............  Significant.
Conneaut Outlet (PA)............       1997  Unknown.............  Unknown.............  Small...............  Unknown.............  Marginal.
Little Mahoning Creek (PA)......       1991  Unknown.............  Unknown.............  Small...............  Unknown.............  Marginal.
Shenango River (PA).............       2010  Yes.................  Unknown.............  Small...............  Unknown.............  Significant.
Little Shenango River (PA)......       2002  Unknown.............  Unknown.............  Small...............  Unknown.............  Significant.
Middle Island Creek (WV)........       2009  Unknown.............  Unknown.............  Small...............  Declining...........  Marginal.
McElroy Creek (WV)..............       2010  Unknown.............  Unknown.............  Unknown.............  Unknown.............  Marginal.
Little Kanawha River (WV).......       2010  Yes.................  Unknown.............  Unknown.............  Unknown.............  Significant.
Hughes River (WV)...............       2008  Unknown.............  Unknown.............  Unknown.............  Unknown.............  Marginal.
North Fork Hughes River (WV)....       2001  Unknown.............  Low.................  Small...............  Declining...........  Significant.
Elk River (WV)..................       2010  Unknown.............  Low.................  Medium..............  Improving...........  Significant.
Ausable River (ON)..............       2008  Yes.................  High................  Large...............  Unknown.............  Stronghold.
Sydenham River (ON).............       2010  Yes.................  High................  Large...............  Unknown.............  Stronghold.
--------------------------------------------------------------------------------------------------------------------------------------------------------

    Butler (2007, pp. 70-71) categorized the extant populations into 
three groups based on population size: general distribution, evidence 
of recent recruitment, and assessment of current viability. Stronghold 
populations were

[[Page 8641]]

described as having sizable populations; generally distributed over a 
significant, and more or less contiguous, length of stream (30 or more 
river mi (48 or more river km)), with ample evidence of recent 
recruitment; and currently considered viable. Significant populations 
were defined as small, generally restricted populations with limited 
recent recruitment and viability. Many significant populations are 
susceptible to extirpation, but this category has a broad range of 
quality. The third category, marginal populations, are defined as those 
which are very small and highly restricted, with no evidence of recent 
recruitment, of questionable viability, and that may be on the verge of 
extirpation in the immediate future. Following this criteria, there are 
7 stronghold populations, 24 significant populations, and 48 marginal 
populations of snuffbox.
    A population is considered extant if live individuals or fresh dead 
specimens have been located since approximately 1985. A population is 
considered to be recruiting if there was recent (within approximately 
10 years) evidence of subadults (generally, individuals less than or 
equal to 1.5 in (3.8 cm) long or less than or equal to 4 years). Table 
2 provides information on the 79 streams thought to harbor extant 
populations. Butler (2007, pp. 160-200) provides the complete 
distributional history of the snuffbox, including streams where the 
snuffbox is thought to be extirpated.

Upper Great Lakes Sub-Basin

    The snuffbox was formerly known from 15 streams and lakes in the 
upper Great Lakes sub-basin. The Fox River system in Wisconsin, 
particularly its major tributary, the Wolf River (and its tributaries), 
had a widespread and locally abundant population. The species is 
thought to be extant in eight sub-basin streams; however, all but the 
Wolf and Grand Rivers have populations that are considered marginal.
    Wolf River--The Wolf River is the major tributary of the Fox River 
draining a large portion of northeastern Wisconsin and flowing 
southward to join the Fox River at Lake Butte Des Morts, near Oshkosh. 
Snuffbox records are known from Shawano, Waupaca, and Outagamie 
Counties. The snuffbox is known from a 30-river-mi (48-river-km) reach 
of the Wolf River (Butler 2007, p. 21). It is one of the few stronghold 
populations, but appears to exhibit a low level of recruitment. Only 4 
of 257 individuals collected in the mid-1990s were less than 6 years 
old (Butler 2007, p. 21). A bridge replacement project on the south 
side of Shawano, scheduled to begin in 2010, may adversely impact the 
large snuffbox bed located just downstream (ESI 2006, p. 10). The zebra 
mussel occurs in this river, with a 0.7 percent infestation rate on 
unionids sampled in 2006 (ESI 2006, p. 6). This large population 
continues to be viable but appears to be in decline (Butler 2008, pers. 
comm.).
    Embarrass River--A western tributary of the lower Wolf River, the 
Embarrass River parallels the western bank of the Wolf River before 
joining it at New London, Wisconsin. A population of the snuffbox is 
located in the headwaters below a small dam at Pella, Wisconsin. 
Records exist for three live individuals and two dead specimens during 
1987-1988 and a single dead specimen in 1995 (Butler 2007, p. 22). Its 
current status is unknown.
    Little Wolf River--The Little Wolf River is a western tributary of 
the lower Wolf River in Waupaca County, Wisconsin. The snuffbox is 
known from a single live individual collected in 1988 at RM 14, below 
the Mill Pond dam at Manawa (Butler 2007, p. 22). Five dead specimens 
were found during 1999 at RM 2, where shells were abundant in a muskrat 
midden (Butler 2007, p. 22). Nothing else is known regarding this 
population.
    Willow Creek--Willow Creek flows eastward into Lake Poygan, a large 
flow-through lake of the Wolf River system, in Waushara County, 
Wisconsin. The snuffbox is known from a single observation of two live 
females in 2001 (Butler 2007, p. 22). No other information is available 
on the status of this population.
    Grand River--The Grand River, a major Lake Michigan tributary, 
represents the largest lotic (moving water) watershed in Michigan and 
is located in the southwestern portion of the State. The snuffbox is 
sporadically distributed in approximately 25 river mi (40 river km) of 
the middle Grand River, approximately between the confluences of the 
Flat and Maple Rivers. The medium-sized population appears to be 
viable, with recruitment noted in 1999 (Badra 2008, pers. comm.; 
Zanatta 2011, pers. comm.).
    Flat River--The Flat River is a tributary to the Grand River. 
Zanatta (2011, pers. comm.) found 32 live snuffbox in the Flat River 
immediately upstream of the confluence with the Grand River in 2009. 
The snuffbox only occurs in the lower Flat River for approximately 0.5 
river mi (0.75 river km) from the mouth upstream to the dam at State 
Route 21 (Zanatta 2011, pers. comm.).
    Maple River--The Maple River is a northeastern tributary of the 
Grand River draining south-central Michigan. A single snuffbox record 
(one live individual) is known from 2001 in southern Gratiot County, 
approximately 20 river mi (32 river km) upstream of the Grand River 
(Badra 2008, pers. comm.). Portions of the Maple River and several 
tributaries have been channelized, but the suitability of these 
channelized areas for the snuffbox is unknown (Badra 2010, pers. 
comm.). The current status of this small population is unknown.
    Pigeon River--The Pigeon River is a headwater tributary of the St. 
Joseph River system of Lake Michigan, flowing westward across northern-
most Indiana, crossing the State border to its confluence in 
southwestern Michigan. One very large fresh dead specimen was found in 
1998, among thousands of shells in LaGrange County, Indiana (Butler 
2007, p. 24). The same site was sampled in 1996 without evidence of 
this species, and relic shells were found at three of nine sites 
sampled in 2004 (Butler 2007, p. 24). The snuffbox's occupied reach 
historically covered more than 10 river mi (16.1 river km) in north-
central LaGrange County. The species is very rare in this river, and 
its viability is unknown.

Lower Great Lakes Sub-Basin

    Of all the water bodies from which the snuffbox was historically 
recorded, 32 are in the lower Great Lakes sub-basin, including several 
chains-of-lakes, springs, and channels in some systems (Clinton, Huron 
Rivers). Historically, sizable populations occurred in some streams 
(Lake Erie; Belle, Clinton, Huron, Portage, and Niagara Rivers), but 
the species had become ``characteristically uncommon'' by the 1970s 
(Strayer 1980, p. 147). A pre-zebra-mussel decline of unionids in Lake 
Erie was noted (Mackie et al. 1980, p. 101), and the snuffbox appeared 
extirpated there by the late 1960s. The Lake St. Clair population of 
snuffbox persisted until around 1983 (Nalepa and Gauvin 1988, p. 414; 
Nalepa 1994, p. 2231; Nalepa et al. 1996, p. 361), which was the year 
the zebra mussel is thought to have invaded (Schloesser et al. 1998, p. 
70). Observations of live and fresh dead snuffbox from the Detroit 
River were made until 1994, but the mussel fauna has since been 
devastated by zebra mussels, and the snuffbox is now considered to be 
extirpated (Schloesser et al. 1998 p. 69; Butler 2007, p. 25). Other 
snuffbox populations in the sub-basin may also have suffered from zebra 
mussel invasions, but not those in the Ausable and Sydenham Rivers in

[[Page 8642]]

Ontario. The lack of impounded area on these streams has likely 
prevented the introduction or the establishment of zebra mussels 
(Dextrase et al. 2000, p. 10; Ausable River Recovery Team 2005, p. 12). 
The snuffbox is considered extant in 10 streams of the lower Great 
Lakes sub-basin, including stronghold populations in the Sydenham and 
Ausable Rivers and sizable but reach-limited populations in the Clinton 
River and Davis Creek. A single fresh dead valve was reported in 1998, 
from among 24 sites sampled in the Thames River, but no evidence of the 
snuffbox was found at 16 Thames sites in 2004 (McGoldrick 2005, pers. 
comm.). Currently, the species is considered extant in Canada only in 
the Ausable and Sydenham Rivers (Morris and Burridge 2006, p. 9). Both 
of these populations are viable.
    Ausable River--The Ausable River is a southeastern tributary of 
Lake Huron, draining southwestern Ontario, Canada. A survey conducted 
in 2008 found that a sizable population of snuffbox occurs in the lower 
portion of the stream in over 36 river mi (59 river km) (Zanatta 2011, 
pers. comm.). The size range of individuals found in the 2008 survey 
indicates recent recruitment in the viable population (Zanatta 2011, 
pers. comm.).
    Pine River--A tributary of the St. Clair River, the Pine River 
flows south and is located in St. Clair County, in southeastern 
Michigan. Although apparently stable, the snuffbox population is small, 
very restricted in range, and has a low potential for viability (Badra 
2002, pers. comm.; Badra and Goforth 2003, p. 23).
    Belle River--The Belle River is another tributary of the St. Clair 
River in St. Clair County, flowing in a southeasterly direction. 
Records for the snuffbox date to the early 1960s, but all live and 
fresh dead records over the past 40 years have been from the same lower 
mainstem site. Historically, a sizable population was found in the 
Belle (65 specimens, 1965). In 2010, Zanatta (2010, pers. comm.) found 
four live individuals at one site and one fresh dead at another site. 
The Belle is located in a primarily agricultural watershed (Hoeh and 
Trdan 1985, p. 115), and is impacted by sedimentation and runoff. The 
population has declined to the point of being small, but shows evidence 
of recruitment and viability (Badra 2002, pers. comm.; Badra and 
Goforth 2003, p. 24; Sherman 2005, pers. comm.).
    Clinton River--The Clinton River is an eastward flowing chain-of-
lakes tributary of Lake St. Clair in southeastern Michigan. The 
snuffbox population in the Clinton River is limited to around 10 river 
mi (16.2 river km) and lakeshore in the western suburbs of Pontiac, 
primarily between Cass and Loon Lakes. This population appears to be 
recruiting (Sherman Mulcrone 2004, p. 64; Zanatta 2011, pers. comm.) 
and viable, although apparently in decline since the early 1990s (Badra 
2002, pers. comm.; Butler 2007, p. 27).
    Sydenham River--The Sydenham River is a large, southeasterly 
flowing, eastern tributary of Lake St. Clair in extreme southwestern 
Ontario. The snuffbox was reported in the mid-1960s and early 1970s, 
but was overlooked during surveys in 1985 (except dead shells) and 1991 
(Butler 2007, p. 28). During the 1997-1999 sampling, a total of 10 live 
and fresh dead individuals were found from 4 of 12 sites, including the 
3 1960s sites (Metcalfe-Smith et al. 2003, p. 41). The snuffbox was 
recorded at a rate of 0.22 per hour of effort during 1997-1998 
(Metcalfe-Smith et al. 2000, p. 728). More recent sampling found 57 
live and fresh dead individuals from 21 collection events (some 
individuals may have been counted multiple times) at six sites during 
2000-2002. The increase in numbers relative to historical collections 
may be attributed to more intensive sampling methods rather than to 
improving population size (Metcalfe-Smith et al. 2003, p. 46), thus 
making population trend assessments difficult (Morris and Burridge 
2006, p. 12). This stronghold population is recruiting (Butler 2007, p. 
28), viable, and is currently known from approximately 30 river miles 
(48 km) of the middle Sydenham.
    Huron River--The Huron River is a major tributary of western Lake 
Erie draining a significant portion of southeastern Michigan. It is a 
complex system of flow-through chains-of-lakes and tributaries. The 
snuffbox is considered extant in two disjunct upper mainstem reaches. 
Individuals in the middle Huron River reach and in Davis Creek are 
considered a single population segment (Marangelo 2005a, pers. comm.).
    Zebra mussels invaded the Huron River system in the early 1990s. 
Zebra mussel densities on individual mussels increased from less than 1 
in spring 1995 to 245 in winter 1998 (Nichols et al. 2000, p. 72). 
Despite the increasing presence of zebra mussels, the Huron population 
is probably recruiting and viable (Butler 2007, p. 29).
    Davis Creek--Davis Creek is a chain-of-lakes in the upper Huron 
River system, primarily in southeastern Livingston County, Michigan. 
The snuffbox appears to be limited to the lower 3 river mi (4.8 river 
km), comprising a single population with one of the extant Huron River 
population segments in this area. This viable population appears to be 
sizable and is experiencing recent recruitment (Marangelo 2005a, pers. 
comm.; Zanatta 2005, pers. comm.).
    South Ore Creek--South Ore Creek is a northern tributary of the 
Huron River, forming a southward flowing chain-of-lakes draining 
southeastern Livingston County, Michigan. The snuffbox was discovered 
in 1999, just upstream of Ore Lake, which is near the Huron River 
confluence (Butler 2007, p. 31). Three subadult snuffbox (two age 2, 
one age 3-4) were recorded. Despite the lack of additional information, 
the small population appears to be viable, based on recent recruitment.
    Portage River--The Portage River is a chain-of-lakes in the 
northwestern portion of the Huron River system. Two University of 
Michigan Museum of Zoology (UMMZ) records suggest historical abundance 
(Badra 2002, pers. comm.). The species was reported as ``rare'' in the 
lower river during 1976-78 (Strayer 1979, p. 94). At least 22 live, 
young (age 4 and younger) individuals were identified in 1998, at one 
of three sites upstream of Little Portage Lake and Portage Lake (Butler 
2007, p. 31). The localized population appears to be medium-sized and 
viable.
    Grand River--The Grand River is a 99-river-mi (159-river-km) 
tributary of Lake Erie, flowing north, then west to its confluence 
northeast of Cleveland, Ohio. Several museum snuffbox records date back 
to the 1800s. Dozens of fresh dead snuffbox were found washed up on the 
banks in the vicinity of the Interstate 90 crossing in Lake County, 
Ohio, following a major flood in 2006 (Butler 2007, p. 32). The species 
is known from approximately 12 river mi (19.3 river km) downstream of 
Harpersfield Dam (Huehner et al. 2005, p. 59; Zimmerman 2008a, pers. 
comm.). The sizable population was considered recruiting, based on the 
1995 Huehner et al. (2005, p. 59) survey.

Upper Mississippi River Sub-Basin

    The snuffbox was historically known from 17 streams in the upper 
Mississippi River sub-basin. Records exist for Mississippi River Pools 
(MRPs) 3-4, 5a-6, and 14-16 (Kelner 2003, p. 6), with early surveys 
summarized by van der Schalie and van der Schalie (1950, p. 456). The 
snuffbox was considered to be extirpated from the mainstem of the 
Mississippi River until 2010, when it was reintroduced (Havlik and 
Sauer 2000, p. 4; Davis and Pletta 2010, p. 2). Only 5 of 17 historical

[[Page 8643]]

populations remain, but they include two of the largest rangewide (St. 
Croix and Bourbeuse Rivers). Three populations, including the St. 
Croix, appear to be declining.
    Upper Mississippi River--The Upper Mississippi River is the portion 
of the Mississippi River upstream of Cairo, Illinois. From the 
headwaters at Lake Itasca, Minnesota, the river flows approximately 
1,250 miles (2,000 km) to Cairo, where it is joined by the Ohio River 
to form the Lower Mississippi River. The snuffbox was reported live in 
the upper river in the 1920s (Grier 1922, p. 15; Grier 1926, p. 119), 
but not from subsequent surveys (254 sites upstream of the Ohio River 
during 1930-1931 (UMMZ, Ellis 1931, pp. 1-10), MRPs 5-7 and 9 in 1965 
(Finke 1966, Table 2; Thiel 1981, p. 16), MRPs 3-11 during 1977-79 
(Thiel 1981, p. 16)). A reintroduction effort into the Mississippi 
River was initiated in 2010, when 200 logperch inoculated with snuffbox 
glochidia were placed into cages in Upper Pool 2 (Davis and Pletta 
2010, p. 2: Delphey 2011, pers. comm.). It is not yet known if this 
reintroduction effort was successful.
    St. Croix River--The St. Croix River is a major south-flowing 
tributary of the upper Mississippi River and forms the border between 
southeastern Minnesota and northwestern Wisconsin. Densities of 
juvenile snuffbox declined at eight sites between 1992 and 2002 
(Hornbach et al. 2003, p. 344). Snuffbox density at Interstate Park 
declined significantly between 1988 and 2004 (WIDNR 2004). A flood in 
2001 may have contributed to these declines in mussel density, but 
post-flood recruitment was also surprisingly low (WIDNR 2004). The St. 
Croix snuffbox population occurs from the Northern States Power Dam, at 
RM 54.2 to RM 36.8 (Heath 2005, pers. comm.); represents the species' 
northernmost occurrence; and despite recent observed declines, remains 
one of the most significant populations rangewide.
    Kankakee River--The Kankakee River is a major, westward-flowing, 
upper Illinois River tributary with its headwaters in northwest Indiana 
and northeast Illinois. The snuffbox was reported over a century ago 
(Baker 1906, p. 63), but surveys in 1911 (43 sites; Wilson and Clark 
1913, pp. 41-50), 1978 (13 sites; Suloway 1981, p. 236), 1975-2000 (18 
samples from an unknown number of sites in Will County, Illinois; 
Sietman et al. 2001, p. 279), and 1999 (4 sites, Stinson et al. 2000, 
Appendix C) failed to find it. It was considered extirpated from the 
Kankakee by Cummings et al. (1988, p. 16), but single fresh dead 
specimens in Illinois (Will County in 1988, Kankakee County in 1991) 
were subsequently found. Only relic shells have been found since 1991. 
The Kankakee River population, if extant, appears small, localized, and 
of doubtful viability.
    Meramec River--The Meramec River is a 236-mi (380-km) tributary 
that flows northeasterly into the Mississippi River downstream of St. 
Louis and drains the northeastern slope of the Ozark Plateaus in east-
central Missouri. Early species lists failed to report the snuffbox 
(Grier 1916, p. 518; Utterback 1917, p. 28). Buchanan (1980, p. 63) 
found fresh dead specimens at three sites and relic shells at two other 
sites sampled in 1977-78. Roberts and Bruenderman (2000, p. 85) sampled 
42 sites in 1997, including 26 of Buchanan's (1980, p. 5) sites, and 
found fresh dead specimens at RM 33.5, 48.8, and 59.8; and one live 
individual at RM 39.8. The live individual (2.4 in (6.1 cm), 
approximately 6 years old) was reported from a reach where a die-off, 
perhaps attributable to disease, was reported in 1978 (Buchanan 1986, 
p. 44). There was an obvious decline of mussels in the system based on 
catch-per-unit-effort data over the 20-year period (Roberts and 
Bruenderman 2000, p. 8). The Meramec snuffbox population is rare, 
sporadically distributed over approximately 26 river mi (41.8 river 
km), and of unknown viability.
    Bourbeuse River--The Bourbeuse River is a 149-mi (240-km), 
northeasterly flowing, northern tributary of the Meramec River, joining 
it at RM 68. The snuffbox is currently distributed over about 60 river 
mi (96.6 river km) upstream of RM 16, plus a disjunct site at the mouth 
of the river. Although it was considered to have ``greatly declined'' 
by the late 1990s (Roberts and Bruenderman 2000, p. 15), post-2000 
sampling indicates that the population is recruiting, viable, and 
improving (McMurray 2006, pers. comm.). The Bourbeuse, one of the few 
stronghold snuffbox populations rangewide, has been augmented with 
laboratory propagated juveniles since 2002 (McMurray 2006, pers. 
comm.).

Lower Missouri River System

    The snuffbox was historically known from four streams in this 
system. The highly disjunct occurrences suggest that it was more 
widespread historically. All populations in the system are considered 
extirpated (Butler 2007, p. 36).

Ohio River System

    Half of the water body occurrences for the snuffbox rangewide are 
known from the Ohio River system. The Ohio River system once 
represented the largest block of available habitat for this species 
prior to the initiation of the navigational improvements in 1830 
(Butler 2007, p. 36). Nearly the entire Ohio River mainstem is now 
impounded with a series of locks and dams (Butler 2007, p. 37). Sizable 
populations historically occurred in at least a dozen streams in the 
system. Today, only French Creek is considered to have a stronghold 
population, although nine others are also significant. Currently, the 
species is known from 45 of the 107 streams of historical occurrence.
    Ohio River--The Ohio River is the largest eastern tributary of the 
Mississippi, with its confluence marking the divide between the upper 
and lower portions of the latter system. Numerous historical records 
are known from throughout the River. Recently, single fresh dead and 
live specimens have been reported from just below Belleville Lock and 
Dam, Ohio and West Virginia, in 1995 and 2001, respectively (ESI 2002, 
p. 27). Having persisted in this highly modified river may indicate 
that the small population exhibits at least a low level of viability.
    Allegheny River--The 325-mi (523-km) Allegheny River drains 
northwestern Pennsylvania and a small portion of adjacent New York 
flowing south before joining the Monongahela River at Pittsburgh to 
form the Ohio River. Snuffbox collections are sporadically known since 
around 1900 in Pennsylvania from Forest County downstream to Armstrong 
County. The snuffbox is currently known from three disjunct sites over 
a 42-river-mi (67.6-river-km) reach centered in Venango County (Butler 
2007, p. 37). Its occurrence in the lower Allegheny River and lower 
French Creek could be considered a single population segment. The 
viability status of the small population is unknown.
    French Creek--French Creek is a major tributary of the middle 
Allegheny River with its headwaters in western New York and flowing 
south into northwestern Pennsylvania. The snuffbox is known from the 
length of the stream in Pennsylvania in Erie, Crawford, Mercer, and 
Venango Counties. Most records date since approximately 1970 (Dennis 
1971, p. 97). Snuffbox collections made during 2002-2004 were 
summarized by Smith (2005, p. 3-9). Live and fresh dead specimens were 
found at 19 sites throughout the stream. The size of the L individuals 
indicated that multiple year classes were represented, including 
subadults. The species stretches for approximately 80 river mi (128.7 
river km) from around RM 10, upstream. The

[[Page 8644]]

population encompasses several of its tributary population segments as 
well, making it relatively more secure when compared to most of the 
other stronghold populations that are linearly distributed and, thus, 
more susceptible to stochastic events (Sydenham, Bourbeuse, and Clinch 
Rivers). The French Creek snuffbox population is considered large and 
viable (Evans 2003a, pers. comm.; Zimmerman 2008c, pers. comm.), 
appears stable, and may represent the best stronghold population 
rangewide.
    West Branch French Creek--West Branch of French Creek follows a 
southerly course to its parent stream in Erie County, Pennsylvania. The 
only record for the snuffbox dates from 1993, but the number of 
specimens and shell condition are unknown (Evans 2003b, pers. comm.). 
Union City Lake isolates the upper French Creek and West Branch French 
Creek population segment from the main French Creek population. The 
snuffbox was not found at three sites sampled in 2006 (Smith 2006, 
pers. comm.). Zimmerman (2008c, pers. comm.) documented 38 live 
individuals at a site near Wattsburg, Pennsylvania. This population 
appears to be small and of unknown viability.
    Le Boeuf Creek--Le Boeuf Creek is a small western tributary of 
upper French Creek flowing in a southerly direction just west of West 
Branch French Creek in Erie County. The first snuffbox collections in 
this creek were made 100 years ago (Ortmann 1909a, p. 188). Two fresh 
dead and 6 relic shells were reported in 1988 (Evans 2003b, pers. 
comm.), and 1 live, 16 fresh dead, and 8 relic specimens were found in 
1991 (Butler 2007, p. 40). Three live individuals were found at a site 
in 2006 (Smith 2006, pers. comm.; Smith et al. 2009, p. 69). The 
snuffbox population has recently recruited and exhibits some level of 
viability, but appears to be very limited in extent.
    Woodcock Creek--Woodcock Creek is an eastern tributary of upper 
French Creek in Crawford County, Pennsylvania. Until recently, the 
snuffbox was thought to be extirpated from this stream. In 2007, one 
live male was found at one of three sites sampled (Smith et al. 2009, 
pp. 84-85). Viability is unknown.
    Muddy Creek--Muddy Creek is an eastern tributary of upper French 
Creek in Crawford County, Pennsylvania. The snuffbox was not discovered 
until the summer of 2003. Forty-two L individuals were reported from 11 
of 20 lower river sites (Morrison 2005, pers. comm.; Mohler et al. 
2006, pp. 581-582). Low numbers were found at most sites, but 18 live 
individuals were collected from a site near the mouth of the river. 
This occurrence is considered to be part of the more extensive French 
Creek snuffbox population. Zimmerman (2008c, pers. comm.) documented 
one live female in 2008. The population is medium-sized, occurs along 8 
river mi (12.9 river km) of the lower mainstem, and is recruiting, as 
recent juveniles were recorded (Morrison 2005, pers. comm.; Mohler et 
al. 2006, p. 576).
    Conneaut Outlet--This stream forms the outlet to Conneaut Lake, 
flowing in a southeasterly direction until its confluence with middle 
French Creek, Crawford County. The snuffbox was first reported by 
Ortmann (1909a, p. 188), and was rediscovered live in 1997, but without 
collection details (Butler 2007, p. 40). No specimens were found at a 
site sampled in 2006 (Smith 2006, pers. comm.). The snuffbox is 
considered rare in this stream and its viability is unknown.
    Little Mahoning Creek--Little Mahoning Creek is a tributary of 
Mahoning Creek, a lower eastern tributary of the Allegheny River 
northeast of Pittsburgh. The snuffbox was discovered in 1991, when 
sampling produced two FD and one R specimen at 1 of 12 sites in the 
system (Butler 2007, p. 41). The lower 10 miles (16 km) of Little 
Mahoning Creek are subject to periodic inundation by a reservoir on 
Mahoning Creek (Butler 2010, pers. comm.). However, the impact of this 
periodic flooding on the snuffbox is not known. A 2007 survey failed to 
find any live or fresh dead snuffbox (Chapman and Smith 2008, p. 166). 
Viability is unknown.
    Shenango River--The Shenango is a large tributary in the Beaver 
River system, a northern tributary of the upper Ohio River in west-
central Pennsylvania. The snuffbox was reported from four sites on the 
Shenango in 1908 (Ortmann 1919, p. 328). Six live individuals were 
collected from three sites sampled in 2001-2002 between Jamestown and 
New Hamburg (about 25 river mi (40.2 river km)). Nelson and Villella 
(2010, p. 17) found 45 L individuals in 2010. The upper reach is 
considered the best habitat in the Shenango River. The population is 
small and has declined, although some recent reproduction is evident 
(Zimmerman 2008b, pers. comm.; Nelson and Villella 2010, p. 17).
    Little Shenango River--The Little Shenango River is a small 
tributary of the upper Shenango River, Mercer County, Pennsylvania. 
This population was not located during limited surveys (Dennis 1971, p. 
97; Bursey 1987, p. 42), but a single fresh dead museum record from 
1991 exists. The species was reported to be relatively abundant and 
reproducing in the lower portion in 2002 (Zimmerman 2008b, pers. 
comm.). Viability of the small population is unknown.
    Middle Island Creek--Middle Island Creek is a small tributary of 
the Ohio River in northwestern West Virginia. The first snuffbox 
records were made at six sites in 1969, when the species was locally 
common in Doddridge, Tyler, and Pleasants Counties (Taylor and Spurlock 
1981, p. 157). The snuffbox was later found at two sites in Tyler 
County in 1980, and the overall mussel population was considered to be 
``thriving'' (Taylor and Spurlock 1981, p. 157). The most recent 
records are for three live individuals in 2009 at two sites and four 
live individuals in 2010 at three sites (Clayton 2011, pers. comm.). 
This snuffbox population has declined, is currently rare, and has 
questionable viability (Zimmerman 2008b, pers. comm.).
    McElroy Creek--McElroy Creek is a tributary to Middle Island Creek 
in West Virginia. There are no historical records for the snuffbox in 
McElroy Creek. Clayton (2011, pers. comm.) reported finding one live 
individual in 2010 in Tyler County. The status of this snuffbox 
population is unknown.
    Muskingum River--The Muskingum River is a large, southerly flowing, 
northern tributary of the upper Ohio River draining a significant 
portion of east-central Ohio. The snuffbox, which has a long collection 
history dating to the early 1800s, occurred along the entire mainstem 
and was locally abundant. Two live individuals and two fresh dead 
shells were found in 1979, but no live or fresh dead snuffbox were 
found in surveys conducted in 1979-81 (Stansbery and King 1983) and in 
1992-93 (Watters and Dunn 1993-94, p. 241). A single live male was 
located during sampling for a construction project in 2005 near 
Dresden, Ohio (Jones et al. 2005, p. 30). Viability of this population 
is unknown.
    Walhonding River--The Walhonding River is a short (23.3 river mi 
(37.5 river km)), east flowing tributary of the Muskingum River in 
central Ohio, forming the latter river at its confluence with the 
Tuscarawas River, and formed by the confluence of the Mohican and 
Kokosing Rivers. The snuffbox historically occurred throughout the 
river. The extant snuffbox reach (RM 1.8-6.8) is downstream from 
Killbuck Creek. The population had apparently declined in range and 
size by the early 1990s, and possibly further since. A once productive 
site about 0.25 mi (0.40 km) downstream of the Killbuck Creek 
confluence yielded only a few mussels

[[Page 8645]]

of very common species in 2006, but no snuffbox (Butler 2007, p. 44). 
The Walhonding River population is considered small and of unknown 
viability.
    Killbuck Creek--Killbuck Creek is a large tributary of the lower 
Walhonding River, flowing south from southern Medina County to 
Coshocton County and entering the latter at approximately RM 7. Live 
and fresh dead snuffbox were found by Hoggarth (1997, p. 33) at eight 
sites from RM 15 to the mouth. Its occurrence has become more sporadic 
in the last 10 years. In spring 2006, 4 live adults were found at 2 
sites approximately 3 river mi (4.8 river km) apart, while 9 large live 
individuals and a single fresh dead specimen were collected near RM 13 
during fall 2006 (Ahlstedt 2007, pers. comm.; Butler 2007, p. 45). Two 
large live males were collected in 2010 (Ahlstedt 2010, pers. comm.). A 
shrinking distribution, declining population size, and lack of evidence 
of recent recruitment suggest that the population may be losing 
viability and trending towards extirpation.
    Little Kanawha River--The Little Kanawha River is a 169-mi (269-km) 
long tributary of the Ohio River in western West Virginia. Schmitt et 
al. (1983, p. 137) reported snuffbox from three sites during a 1981-82 
survey. Snuffbox were not documented again in the Little Kanawha River 
until 2010, when four live individuals, including at least one young 
mussel, were found at a site in Gilmer County, West Virginia (Clayton 
2011, pers. comm.). Additionally, two fresh dead specimens were found 
in 2010, below Wells Dam near Elizabeth, Wirt County, West Virginia 
(Clayton 2011, pers. comm.). The current status of this snuffbox 
population is unknown.
    Hughes River--The Hughes River is an 18-mile (29-km) long tributary 
of the Little Kanawha River in western West Virginia. Schmitt et al. 
(1983, p. 137) reported snuffbox during a 1981-82 survey. No additional 
snuffbox were found in the Hughes River until 2008, when one fresh dead 
specimen was found in Wirt County (Clayton 2011, pers. comm.). The 
current status of this snuffbox population is unknown.
    North Fork Hughes River--The North Fork Hughes River is a westerly 
flowing tributary of the Hughes River in the lower Little Kanawha River 
system in northwestern West Virginia. The snuffbox was found at one of 
six North Fork sites sampled during a 1981-1982 survey of the Little 
Kanawha River system (Schmidt et al. 1983). A total of 41 live adult 
individuals (23 reported as gravid) were reported at 5 sites located 
over a 1.5-mi (2.4-km) reach in North Fork State Park, Richie County, 
in 1993 (Butler 2007, p. 46). At least 10 live individuals were found 
at a site in the park in 1997 (Butler 2007, p. 46), and a single fresh 
dead specimen was collected at an additional site downstream in 2001 
(Butler 2007, p. 46). This small snuffbox population is declining and 
currently restricted to less than 4 river mi (6.4 river km), but may be 
viable.
    Elk River--The Elk River is a major, 181-mi (291-km) tributary in 
the lower Kanawha River system draining central West Virginia flowing 
west to the Kanawha at Charleston. The snuffbox went undetected in a 
1920s survey (Butler 2007, p. 46). Ten live individuals were collected 
during 1991-1995, the smallest being about 5 years old (Butler 2007, 
pp. 46-47). Collectively, 16 live individuals were identified at 8 
sites in a 13-river-mi (20.9-river-km) reach in Kanawha County in 2002, 
and 4 live individuals were found at 4 sites in 2004 over a 16.8-river-
mi (27-river-km) reach farther upstream (Douglas 2005, pers. comm.). 
This medium-sized population extends over 30 river mi (48.3 river km), 
is viable, and may have improved since the 1970s.
    Tygarts Creek--Tygarts Creek is a small, north-flowing, southern 
tributary of the Ohio River in northeastern Kentucky. Thirteen snuffbox 
were reported from one of five sites sampled in 1977 (Taylor 1980, p. 
90). Fresh dead specimens are also known from 1981 and 1987 (Cicerello 
2003, pers. comm.). Nine live (Butler 2007, p. 47) and 36 fresh dead 
specimens were found at 2 sites, respectively, in 1988, while 1 live 
and 2 fresh dead were reported from at least 2 sites in 1995 (Cicerello 
2003, pers. comm.). The overall mussel population appeared ``healthy'' 
in 1977 (Taylor 1980), but the small snuffbox population has recently 
declined, and its viability is unknown.
    Scioto River System--The Scioto River system in central and south-
central Ohio is a major northern tributary of the upper Ohio River. The 
system was one of the most routinely sampled watersheds for mussels 
(mostly OSUM records), and historically harbored a large and thoroughly 
dispersed snuffbox population in the mainstem and 16 tributaries. The 
system was either exceptional for its snuffbox population, or it 
provided a general historical perspective of what researchers may have 
found if other systems had been as thoroughly sampled. Sizable 
populations were noted in at least the Olentangy River, Big Darby 
Creek, and Big Walnut Creek. Development associated with the Columbus 
metropolitan area has taken a major toll on the aquatic fauna. 
Pollutants from the 1800s included wastes from sawmills, breweries, and 
slaughterhouses (Butler 2007, p. 48). Only a few fish species were 
found in the Scioto River 100 years ago (Trautman 1981, p. 33). 
Currently, 90 to 95 percent of the normal summer-fall flow in the river 
consists of wastewater treatment plant discharges (Yoder et al. 2005, 
p. 410). Museum records indicate that the snuffbox had completely 
disappeared from the mainstem by the 1970s. A series of reservoirs 
around Columbus fragmented habitat and eliminated or reduced 
populations (Olentangy and Scioto Rivers; Alum, Big Walnut and Deer 
Creeks). Currently, remnant populations remain in six streams, making 
the snuffbox precariously close to extirpation throughout this once 
rich system.
    Olentangy River--The Olentangy River is a major headwater tributary 
of the Scioto River, draining central Ohio and flowing south to its 
confluence in Franklin County. OSUM snuffbox records date to the 1870s, 
although most are from the 1950s and 1960s. The snuffbox was reported 
from 15 of 31 mainstem sites collected during a 1960-1961 survey, when 
it appeared ``fairly common'' in the lower river (Stein 1963, p. 138). 
A single live individual in southern Delaware County and two fresh dead 
specimens in eastern Marion County were found among 30 sites in 1989, 
with relic shells at 7 other sites (Hoggarth 1990, pp. 20-27). The 
small population has declined (Hoggarth 1990, p. 14), and its viability 
is unknown.
    Big Darby Creek--Big Darby Creek is one of the major tributaries 
draining the northwestern portion of the Scioto River system in central 
Ohio. Dozens of large OSUM lots of snuffbox date to the late 1950s; six 
Pickaway County collections in 1962 alone had 250 live and fresh dead 
specimens. Watters (1990, p. 4; 1994, p. 100) surveyed 42 mainstem 
sites in 1986 and 49 sites in 1990. Combining the data from both years, 
80 live and fresh dead snuffbox were collected at 22 sites (Watters 
1994, p. 101). The population in 1990 occurred in a reach from 
approximately RM 11.5 to RM 42.5. The snuffbox was recruiting (Watters 
1994, p. 101); four individuals during both 1986 and 1990 were 2 to 5 
years of age. The overall population trend over the past 40 years has 
been downward. Between 1986 and 1990, the number of live and fresh dead 
specimens was reduced from 54 to 16, and the population's distribution 
declined from 17 to 8 sites. Two fresh

[[Page 8646]]

dead specimens were found at sites in Franklin (1996) and Pickaway 
(2000) Counties, and three other sites produced only relic specimens 
(OSUM records). This historically large snuffbox population has 
declined to marginal status, and its viability is questionable.
    Little Darby Creek--Little Darby Creek is the major tributary in 
the Big Darby Creek system, flowing in a southeasterly direction to its 
confluence in southwestern Franklin County, Ohio. The 25 OSUM lots for 
this species are small (fewer than 5 specimens per lot), date to the 
early 1960s, and represent lower mainstem sites in Madison County. 
Single fresh dead and relic specimens were collected in 1999, from a 
Union County site (OSUM 66740), where live individuals were collected 
in 1964 (Stein 1966, p. 23). This site yielded only relic specimens in 
1990 (Watters 1990, Appendix A.11; 1994, p. 102). Overall, the snuffbox 
was historically known from 35 river mi (56 river km). The well-
documented OSUM collection history illustrates the steady decline of a 
snuffbox population nearing extirpation.
    Salt Creek--Salt Creek is an eastern tributary in the Scioto River 
system, south-central Ohio. All records (OSUM) were collected in the 
lower mainstem (Ross County) beginning in 1958. A single live 
individual from 1987 represents the last known record. The mussels in 
this system ``have been heavily impacted, apparently by the towns of 
Adelphi and Laurelville'' (Watters 1992, p. 78). The current status of 
this snuffbox population is unknown.
    Scioto Brush Creek--Scioto Brush Creek is a small, western 
tributary of the lower Scioto River in Scioto County, south-central 
Ohio. The snuffbox was discovered here in the 1960s (Watters 1988a, p. 
45). Three live and fresh dead specimens from 2 sites and relic shells 
from 2 other sites were collected during a 1987 survey covering 11 
sites (Watters 1988a, pp. 210-220). The snuffbox population, 
collectively known from five fragmented sites along the lower two-
thirds of stream, is small, and its viability is unknown.
    South Fork Scioto Brush Creek--South Fork Scioto Brush Creek is a 
small tributary of Scioto Brush Creek, in the lower Scioto River 
system. A single snuffbox was found during a survey of five sites in 
1987 (Watters 1988a, pp. 210-220). The South Fork and Scioto Brush 
Creek populations can be considered a single population unit; the 
viability of this unit is uncertain.
    Kinniconick Creek--Kinniconick Creek is a small, southern tributary 
of the Ohio River in northeastern Kentucky. Snuffbox were reported live 
from 4 of 15 sites sampled in 1982, with relic shells from an 
additional 2 sites (Warren et al. 1984, pp. 48-49). Single fresh dead 
and live snuffbox were collected in 2001 and 2004, respectively, from 
sampling efforts at several sites (Butler 2007, p. 51), and a single 
fresh dead specimen was found while resurveying four sites in 2005 
(Butler 2007, p. 51). The snuffbox declined in the past few decades, it 
is considered rare, and its viability is uncertain.
    Little Miami River--The Little Miami River is a northern tributary 
of the Ohio River in southwestern Ohio, flowing south into the latter 
at the eastern fringe of the Cincinnati metropolitan area. Snuffbox 
records from the Little Miami date to the mid-1800s, but most 
collections are from the past several decades. Seven fresh dead 
specimens were found at 4 of 46 mainstem sites surveyed during 1990-
1991, with 10 relic shells at 6 other sites (Hoggarth 1992, p. 265). 
The fresh dead specimens were found in approximately 20 river mi (32.2 
river km), mostly in Warren County. Current viability of this small 
population is unknown.
    Licking River--The Licking River is a southern tributary of the 
Ohio River in northeastern Kentucky, flowing in a northwesterly 
direction to its confluence across from Cincinnati. The snuffbox 
occurred at 13 of 60 historical mainstem sites below Cave Run Reservoir 
(Laudermilk 1993, p. 45) and a preimpoundment site in the reservoir 
footprint (Clinger 1974, p. 52). The population extended approximately 
50 river mi (80.5 river km). All collections of snuffbox are small in 
number (Butler 2007, p. 52). A single live individual and a fresh dead 
specimen were found at 2 sites, and relic shells were reported from 7 
other sites among 49 sites sampled in 1991 (Laudermilk 1993, p. 45). 
Single live and fresh dead snuffbox were collected in 1999 (Cicerello 
2003, pers. comm.), and a single live individual was found in 2006 
(Butler 2007, p. 53). At this location, the snuffbox has become very 
rare and sporadic in occurrence, and its viability is questionable.
    Slate Creek--Slate Creek is a southern tributary of the Licking 
River below Cave Run Dam in east-central Kentucky. Historically, the 
snuffbox was considered ``extremely abundant throughout the stream'' 
(Taylor and Spurlock 1983) and collectively known from six sites 
(Laudermilk 1993, p. 45). Seventeen dead specimens were recorded from a 
site in 1987 (Cicerello 2003, pers. comm.). A single fresh dead and 
seven relic specimens were found at three sites sampled in 1991 (Butler 
2007, p. 53), when it was considered ``occasional'' in distribution 
(Laudermilk 1993, p. 45). Twelve live individuals were found in 1992 
(Cicerello 2003, pers. comm.). Subsequent sampling has produced no 
additional snuffbox; two sites and four sites yielded only relic 
specimens in 2001 and 2002, respectively (Cicerello 2005, pers. comm.). 
If extant, the population is marginal at best, with unlikely viability.
    Stillwater River--The Stillwater River is a 67-mi (108-km), western 
tributary of the Great Miami River draining southwestern Ohio. The 
species was collectively known from eight sites throughout the river 
(Watters 1988a, pp. 59-71; OSUM records). One fresh dead specimen below 
Englewood Dam in Montgomery County was found among 18 sites surveyed in 
1987, with relic shells from 5 other sites (Watters 1988a, pp. 59-71). 
No other information on the small population is available, and its 
viability is unknown.
    Middle Fork Kentucky River--The Middle Fork is one of three 
headwater tributaries (with the North and South Forks) forming the 
Kentucky River, flowing in a northerly then westerly direction and 
draining a portion of southeastern Kentucky. The snuffbox was first 
reported in 1966. Three live individuals and a relic shell were found 
at three sites in 1996, and a single live individual was collected from 
another site in 1997 (Cicerello 2003, pers. comm.). All sites occur 
within a 10-river-mi (16-river-km) reach above Buckhorn Reservoir in 
Leslie County. This small population has unknown viability.
    Red Bird River--The Red Bird River is a north-flowing headwater 
tributary of the South Fork Kentucky River in Clay County, southeastern 
Kentucky, forming the latter at its confluence with Goose Creek. Ten 
fresh dead specimens were recorded from two sites in 1988, and three 
live and one fresh dead snuffbox were collected from four sites in 1995 
(Cicerello 2003, pers. comm.). This small population occurs 
sporadically in the lower 20 river mi (32 river km), and viability is 
unknown (Cicerello 2003, pers. comm.; 2006, pers. comm.).
    Red River--The Red (or North Fork Red) River is a westerly flowing 
tributary of the upper Kentucky River in eastern Kentucky. No live 
snuffbox were found in surveys of the 9-river-mi (15-river-km) reach of 
the Wild River section during surveys of 1980, 1986, and 1991 (Houp 
1980, p. 56; 1993, p. 96), but two fresh dead and one live snuffbox 
were found at three sites in 1988, while five live individuals were 
found in 1996 (Cicerello 2006, pers.

[[Page 8647]]

comm.). Mostly males have been found since 2002, and they are being 
held in captivity for future culture efforts (Butler 2007, p. 55). A 
small population persists over a 10-river-mi (16-river-km) reach in the 
lower section of the Red River Gorge Geological Area of the Daniel 
Boone National Forest in Menifee, Wolfe, and Powell Counties (Cicerello 
2006, pers. comm.). Viability of this population is unknown.
    Rolling Fork Salt River--The Rolling Fork is a major southern 
tributary of the Salt River in central Kentucky, flowing in a 
northwesterly direction to join the Salt near its mouth. The snuffbox 
was first reported in 1958 (Rosewater 1959, p. 62). Seven fresh dead 
specimens and a single live subadult were collected in 1988, from four 
sites in Larue, Marion, and Nelson Counties (Cicerello 2003, pers. 
comm.; Haag 2006, pers. comm.). A survey of 12 mainstem and 30 
tributary sites in the Rolling Fork system in 1998-1999 yielded no 
evidence of the snuffbox, prompting an investigator to consider it 
extirpated (Akers 2000, p. 13), but occasional specimens may still be 
found (Butler 2007, p. 55). The species is sporadically distributed 
over 40 river miles of the upper river (Cicerello 2006, pers. comm.). 
If it is still extant, the viability of this small population is 
unknown.
    Green River--A major southern tributary of the lower Ohio River, 
the Green River flows in a westerly direction and drains west-central 
Kentucky. Ortmann (1926, p. 182) considered the snuffbox to be well-
distributed over the system, but not abundant. Large museum collections 
of snuffbox were taken from Munfordville during 1961-1966, but only six 
relic shells were reported there in 1967. The snuffbox has been rare 
since. Five live and fresh dead snuffbox were collected at 4 of 42 
sites during 1987-1989 sampling in Mammoth Cave National Park 
(Cicerello and Hannan 1990, pp. 16-17). Three live and six fresh dead 
snuffbox were reported in the upper Green River from 1984-1990 
(Cicerello 2003, pers. comm.). A single live individual was collected 
in Taylor County in 1989 (Layzer 2009, pers. comm.), but no evidence of 
the snuffbox was reported at numerous other sites in 1999, 2000, 2001, 
and 2003 (Cicerello 2006, pers. comm.). Once abundant and occurring 
over 200 river mi (322 river km), the species has become exceedingly 
rare since the 1960s. Current snuffbox viability is unknown, and it may 
be nearing extirpation from the entire Green River system, where it was 
formerly known from eight tributaries.
    Wabash River system--The Wabash River is the second largest sub-
basin within the Ohio River system, the watershed of the 350-mi (563-
km) river encompassing much of Indiana, west-central Ohio, and 
southeastern Illinois. The mainstem and at least 27 streams had one of 
the largest snuffbox population clusters. The species persists today as 
seven small populations in the system; the viability of these 
populations is unknown (Butler 2007, p. 57).
    Salamonie River--The Salamonie River is a southern tributary of the 
upper Wabash River, flowing in a northwesterly direction and draining 
east-central Indiana. Two historical museum records were found. Nine 
sites were surveyed during 1993-1994, without finding any evidence of 
the snuffbox (ESI 1995, p. 19). The snuffbox was rediscovered in 2004, 
above Salamonie Reservoir, where two live individuals at one site and 
fresh dead shells, including a very small juvenile, were found at 
another site 2 mi (3 km) away (Fisher 2005, pers. comm.). The small 
population is considered to be recruiting and viable at some level.
    Tippecanoe River--The largest tributary of the upper Wabash River 
system, the Tippecanoe River drains north-central Indiana and flows 
westerly, then southerly before joining the Wabash near Lafayette. 
Nearly all records of the snuffbox were made in the past 20 years. Two 
weathered shells were found in the lower mainstem among 16 sites 
sampled in 1987 (Cummings et al. 1987, p. 25; Cummings and Berlocher 
1990, p. 93) and 30 sites in 1991-1992 (ESI 1993, p. 68). One L 
individual and over 32 fresh dead specimens were found at a site at the 
upper end of Freeman Reservoir during a 1993 drawdown that may have 
contributed to their demise (Fisher 2003, pers. comm.). A single fresh 
dead specimen was found below Shafer Reservoir among 13 sites sampled 
in 2003 (ESI 2003, p. 9). The viability of this declining population is 
unknown, but it appears close to extirpation (Fisher 2003, pers. 
comm.).
    Embarras River--The Embarras River is a southerly flowing, western 
tributary of the lower Wabash River in southeastern Illinois. Museum 
lots represent collections dating to 1956 and contain snuffbox from 
nine mainstem and two tributary sites. A total of 9 live and 15 fresh 
dead specimens were collected at four sites in 1986, in Coles and 
Douglas Counties (Cummings et al. 1988, p. 8). Although overall mussel 
abundance at the 21 sites sampled in both 1956 and 1986 dropped 86 
percent, the snuffbox was one of only five species that showed 
relatively stable population size over the 30-year period (Cummings et 
al. 1988, p. 9). Additional L and FD snuffbox from museum collections 
were recorded from single sites in 1988. Three L and eight FD snuffbox 
were found at two sites in 1992, and one live and three fresh dead were 
found at three of six sites surveyed during 2001-2002. Since 1986, the 
small snuffbox population has occurred sporadically at six sites over 
50 river mi (80 river km) of the upper river. The species was reported 
as significant and viable by Butler (2007 pers. comm.), but it has 
declined to some extent. Recent surveys, however, documented only one 
live individual in 2005 and 5 live adult males in 2008, indicating that 
the Embarras River population may be closer to a marginal population 
than a significant one (Tiemann 2010, p. 53).
    Sugar Creek--Sugar Creek is a tributary in the upper East Fork 
White River system, draining central Indiana east and south of 
Indianapolis. A single live individual from one site, fresh dead 
specimens from seven sites, and relic shells from an additional eight 
sites were reported in 1990 (Harmon 1992, pp. 40-41 1998). The snuffbox 
population occurred sporadically over 35 river mi (56 km) to near the 
mouth. Only relic shells were found while resampling some historical 
sites in 1995, 1998, and 2001 (Butler 2007, p. 59). It is questionable 
whether the population remains extant.
    Buck Creek--Buck Creek is a southerly flowing, western tributary of 
Sugar Creek in the upper East Fork White River system east of 
Indianapolis. A fresh dead snuffbox was found near the mouth and relic 
specimens at an upstream site in 1990 (Harmon 1992, p. 41). Similar to 
the parent stream population in Sugar Creek, the snuffbox may already 
be extirpated in Buck Creek (Fisher 2003, pers. comm.).
    Muscatatuck River--The Muscatatuck River is a large, westerly 
flowing tributary of the upper East Fork White River in southeastern 
Indiana. The snuffbox was first reported from the stream by Daniels 
(1903, p. 646). Fresh dead specimens (unknown number) were recorded at 
a site downstream from Graham Creek that was sampled in 1988 (Harmon 
1989, p. 118). Status and viability of snuffbox in the Muscatatuck 
River are unknown.
    Graham Creek--Graham Creek flows southwesterly to join Big Creek in 
forming the Muscatatuck River in the East Fork White River system in 
southeastern Indiana. The species was found fresh dead (numbers 
unknown) at six sites over 10 river mi (16 river km) of the lower 
stream in Jennings County

[[Page 8648]]

in 1988 (Harmon 1989, p. 117), and a single fresh dead specimen was 
found in 1990 (Harmon 1998). Viability of these small populations is 
unknown.
    Cumberland River System--Snuffbox populations are known from the 
mainstem Cumberland River and 6 of its tributaries. With few 
exceptions, most mainstem records were made prior to the 1920s, when 
the species was locally common (Wilson and Clark 1914, p. 45). The 
snuffbox is considered extirpated from the mainstem. Currently, a 
single tributary population may be extant, but is considered not 
viable. The species is likely to become extirpated from the entire 
river system in the foreseeable future.
    Buck Creek--Buck Creek is a southerly flowing, northern tributary 
of the upper Cumberland River below Cumberland Falls in southeastern 
Kentucky. One dead valve was found at a site in 1981 (Clarke 1981b, 
Appendix), and two live and one fresh dead snuffbox were reported from 
three sites during 1983-1984 (Schuster et al. 1989, p. 82). The species 
was also reported live from a lower mainstem site among seven sites 
sampled from 1987-1990 (Layzer and Anderson 1992, p. 16). A recent 
survey found only relic shells at 3 of 23 sites (Hagman 2000, p. 21). 
If extant, the declining snuffbox population in Buck Creek is likely to 
become extirpated in the foreseeable future.

Tennessee River System

    The Tennessee River is the largest tributary of the Ohio River, 
draining seven southeastern States and joining the Ohio near its mouth 
in western Kentucky. The snuffbox originally was known from throughout 
all but the lower section of river and 17 of its tributaries. Hundreds 
of miles of large river habitat on the mainstem have been lost under 
nine reservoirs, with additional dams on several tributaries (Clinch, 
Holston, and Elk Rivers) (Tennessee Valley Authority (TVA) 1971, p. 4). 
The loss of mussel resources has been substantial (Watters 2000, p. 
262). Muscle Shoals, the 53-river-mi (85-river-km) reach in 
northwestern Alabama, historically harbored 69 mussel species, the most 
diverse mussel fauna ever known (Garner and McGregor 2001, p. 155). The 
construction of three dams (Wilson in 1925, Wheeler in 1930, and 
Pickwick Landing in 1940) inundated most of the mussel beds. No live 
snuffbox have been reported at Muscle Shoals for around 100 years 
(Garner and McGregor 2001, p. 162). The snuffbox may persist in the 
mainstem at a very low density and in only five tributaries. The Clinch 
River maintains a stronghold population, but highly restricted 
populations persist in the other streams.
    Clinch River--The 350-mi (563-km) Clinch River is a major tributary 
of the upper Tennessee River originating in southwestern Virginia, and 
flowing in a southwesterly direction to its confluence near Kingston in 
eastern Tennessee. No other river in North America has extant 
populations of more federally endangered (15) species of mussels than 
does the upper Clinch River above Norris Reservoir. The snuffbox was 
reported from nine sites by Ortmann (1918, pp. 601-606). Museum records 
from Hancock County, Tennessee, during 1965-1971 documented a very 
large population of snuffbox. The snuffbox is generally distributed 
from RM 170 to RM 195 in Hancock County, but is sporadic in Virginia 
(RM 213-235), where it has recently declined (Butler 2007, p. 62). The 
snuffbox population is recruiting, viable, and currently stable, 
although decreased in size and range from 40 years ago. The Clinch 
River ranks among the six stronghold snuffbox populations rangewide.
    Powell River--The Powell River is the major tributary of the upper 
Clinch River flowing in a southwesterly direction parallel to and 
northwest of the Clinch River in southwestern Virginia and northeastern 
Tennessee. The snuffbox was reported at three sites by Ortmann (1918, 
pp. 597-598), five sites during 1973-1978 by Dennis (1981, p. 3), four 
sites from 1975-1978 by Ahlstedt and Brown (1979, p. 42), and four 
Virginia sites in 1988-1989 by Wolcott and Neves (1994, p. 7). Large 
collections attest to its former abundance. The species was found live 
and fresh dead in the Powell River, Tennessee, during 1989-1990 (Hubbs 
et al. 1991, Appendix A). Of twenty two sites sampled in the Powell 
River, Johnson (2010) collected seven L individuals among three sites 
between RM 80.4 and 95.3. The population has declined, viability is 
questionable, and its extirpation may be imminent (Butler 2007, p. 63).
    Tennessee River--The snuffbox originally was known from all but the 
lower section of the river. Butler (2007, p. 61) reported the snuffbox 
as ``believed to be extirpated from the entire Tennessee River.'' 
However, Yokley (2002, p. 1) collected a single fresh dead male in 2002 
at the U.S. 231 Bridge, Madison and Morgan Counties, Alabama. In 2006, 
one live female was found at the same location, although it was the 
only snuffbox out of 8,978 mussels collected at the site (Yokley 2006, 
p. 1). Nothing further is known about the status of the snuffbox in the 
Tennessee River mainstem.
    Paint Rock River--The Paint Rock River is a southerly flowing, 
northern tributary of the southern bend of the Tennessee River in 
northeastern Alabama and adjacent Tennessee. The snuffbox was first 
reported from one of six mainstem sites by Ortmann (1925, p. 359). No 
evidence of snuffbox was found in two surveys during 1965-1967 (Isom 
and Yokley 1973, p. 444) and a 1980 survey (Butler 2007, p. 64). Twelve 
live and fresh dead snuffbox were found at four sites between RMs 13 
and 21 (Ahlstedt 1995-1996, p. 70). The species was again absent from 
10 upper mainstem sites surveyed in 2002 (Godwin 2002, p. 9). Four 
fresh dead specimens of varying sizes were found at lower river sites 
in 2002 (Fraley 2003, pers. comm.; Smith 2005, pers. comm.) and 2003-
2006 (Freeman 2006, pers. comm.). One live and 11 fresh dead specimens 
were found at RM 21 in 2005, and 2 live and 16 fresh dead were 
collected at RM 31 in 2007 (Gangloff 2007, pers. comm.). In July 2008, 
Freeman (2008, pers. comm.) observed multiple age classes (sizes) of 
fresh dead snuffbox in middens between RM 34.7 and 32.5. Fobian et al. 
(2008, p. 14) collected 21 live snuffbox at 7 sites and fresh dead 
specimens at 8 sites between RM 46.7 and 13.1. A stronghold snuffbox 
population exists between RMs 13 and 44, and is recruiting, viable, and 
has clearly improved since 1980.
    Elk River--The Elk River is a large, northern tributary flowing 200 
river mi (322 river km) in a southwesterly direction in the southern 
bend of the Tennessee River in south-central Tennessee and north-
central Alabama. Snuffbox collections have been sporadic. The species 
was found at 2 sites in the mid-1960s (Isom et al. 1973, p. 440), and a 
single live individual was found among 108 sites sampled in 1980 
(Ahlstedt 1983, p. 47). Single specimens were also reported from 4 
sites sampled in the lower river in 1997 (Madison and Layzer 1998, 
Table 6) and 16 sites sampled in 1999 (Service 1999, p. 3). A very 
large fresh dead specimen was found at RM 51 among 4 sites sampled in 
2001 (Hubbs 2002, p. 5; Butler 2007, p. 65). A single live and a fresh 
dead snuffbox were found at a site in Giles County during qualitative 
sampling events at five sites in 2005 (Ahlstedt et al. 2006). Ford 
(2008, pers. comm.) reported collecting a fresh dead specimen at 
Stairstep Shoals in Giles County, Tennessee, in July 2007. The small 
snuffbox population has recently recruited and exhibits some level of 
viability, and its numbers appear relatively stable in recent history.

[[Page 8649]]

    Duck River--The Duck River is the downstream-most large tributary 
of the Tennessee River draining south-central Tennessee and flowing 285 
river miles (459 river km) west to its confluence near the head of 
Kentucky Reservoir. The snuffbox historically occurred throughout the 
Duck River and, based on museum records, was locally common 40 to 50 
years ago, but was absent in surveys from RM 180 downstream in the mid-
1970s (Ahlstedt 1981, p. 62; Dennis 1984, p. 38). Two live individuals 
were collected from 2 of 99 sites surveyed in 1979 (Butler 2007, p. 
66). A single live individual was discovered in Maury County among 72 
sites sampled during 2000-2003 (Ahlstedt et al. 2004, p. 119), but none 
were found at 11 lower sites surveyed in 2000 (Schilling and Williams 
2002, p. 409). The snuffbox is very rare, and its viability is 
uncertain.

Lower Mississippi River Sub-Basin

    The Lower Mississippi River Sub-basin includes 954 miles (1,535 km) 
of the Mississippi River from its confluence with the Ohio River at 
Cairo, Illinois, to its mouth in the Gulf of Mexico. The snuffbox is 
known from five streams in this system, four of which are tributaries 
to the White River.
    St. Francis River--The St. Francis River is a major tributary of 
the lower Mississippi, with its headwaters in southeastern Missouri and 
flowing south into northeastern Arkansas. The only Arkansas records 
available for this 450-mi (724-km) river are from 1964, located 
approximately 1 mi southwest of Parkin in Cross County (Bates and 
Dennis 1983, p. 63; Harris et al. 2007, p. 10). Snuffbox records exist 
for Butler, Wayne, and Stoddard Counties, Missouri, where it was 
considered ``locally abundant'' (Oesch 1984, p. 235). The species is 
known from above Wappapello Reservoir, but was absent from Missouri 
surveys conducted below Wappapello Dam in 1983 (Bates and Dennis 1983, 
p. 63) and 1986 (Ahlstedt and Jenkinson 1991, p. 240). Twelve live 
snuffbox were sampled at sites in 2002 (Hutson and Barnhart 2004, pp. 
84-85). Live individuals were found during collections at RM 172.1 in 
2005 and 2006 (Butler 2007, p. 67). The snuffbox is restricted to a 10-
mi (16-km) reach (RM 172.1-182.0) on the northeastern edge of the Ozark 
Plateaus in the vicinity of Sam A. Baker State Park, Wayne County 
(Hutson and Barnhart 2004, p. 85). This medium-sized snuffbox 
population appears to be stable and viable, but restricted in 
distribution.
    White River System--The 690-mi (1,110-km) White River is a large 
tributary system of the western bank of the Mississippi River. A 
snuffbox population once occurred in the mainstem and six of its larger 
tributaries. The last record from the mainstem in Arkansas is pre-1921 
(Harris et al. 2007, p. 10). Highly restricted populations persist in 
four streams.
    Buffalo River--The Buffalo River is a large, eastward-flowing 
tributary of the middle White River in north-central Arkansas. The 
snuffbox was not found during surveys in 1910 (26 sites; Meek and Clark 
1912, p. 13) or 1995 (40 sites; Harris 1996, p. 9), but two live 
individuals were found at a single site among 60 sites surveyed in 2006 
(Matthews 2007, pers. comm.). The small population occurs in the lower 
river in Marion County, and its viability is unknown.
    Black River--The Black River is the largest tributary in the White 
River system, draining much of southeastern Missouri and northeastern 
Arkansas before flowing in a southerly direction into the White River 
near Newport, Arkansas. A long but sporadic collection history for the 
snuffbox appears in the 300-mi (483-km) Black River. A single, 
approximately 4-year-old live male was collected at RM 65.5, Wayne 
County, among 51 Missouri sites sampled in 2002 (Hutson and Barnhart 
2004, p. 154). The species has become extirpated from the lower river 
on the Mississippi Embayment, including Arkansas. This population of 
snuffbox appears rare but viable at some level.
    Spring River--The Spring River is a large tributary of the Black 
River that drains the eastern Ozark Plateaus in south-central Missouri 
and northeastern Arkansas. Based on pre-1986 records, the snuffbox was 
known in low numbers from at least four sites in approximately 20 river 
mi (34 river km) of the lowermost mainstem in Arkansas (Harris and 
Gordon 1987, p. 53). A single live adult male was found in Lawrence 
County in 2005, and represents the first live specimen found in 
Arkansas in more than 20 years (Butler 2007, p. 69). Further, 53 fresh 
dead snuffbox were collected in four large muskrat middens (Harris et 
al. 2007, p. 15). The extent of the population is not known, but it is 
probably limited to relatively few miles in the lower mainstem in 
Lawrence and Randolph Counties. This population appears small, and its 
status and viability are unknown.
    Strawberry River--The Strawberry River is a western tributary of 
the Black River draining a portion of the southeastern Ozark Plateaus 
in northeastern Arkansas. The only snuffbox records were from around 
1983 and 1997 in the middle mainstem in Sharp County (Butler 2007, p. 
69). No other details on these collections or the status of the 
population are known. Considering the dearth of records, the snuffbox 
appears to be very rare in the Strawberry River, and its viability is 
unknown.

Summary of Snuffbox Population Estimates and Status

    The snuffbox has declined rangewide and appears to be extant in 79 
of 210 streams and lakes of historical occurrence, a 62 percent decline 
in occupied streams. Realistically, much more than 62 percent of the 
habitat historically available for this species no longer supports its 
populations. Habitat losses measured in the thousands of miles have 
occurred rangewide. As multiple streams may comprise single snuffbox 
population segments (for example, the French Creek system), the actual 
number of extant populations is somewhat less. Extant populations, with 
few exceptions, are highly fragmented and restricted to short reaches. 
The elimination of this species from scores of streams and thousands of 
miles of stream reaches indicates catastrophic population losses and a 
precipitous decline in overall abundance. It is reasonable to estimate 
that total range reduction and overall population losses for the 
snuffbox each approximate, if not exceed, 90 percent.

Public Comments

    In the proposed rule published on November 2, 2010 (75 FR 67552), 
we requested that all interested parties submit information that might 
contribute to development of a final rule. We reviewed all comments 
received for substantive issues and new information regarding the 
proposed listing of these two species, and we have addressed those 
comments below.

Summary of Comments and Recommendations

    During the open comment period for the proposed rule (75 FR 67552), 
we requested all interested parties submit comments or information 
concerning the proposed listing of the rayed bean and snuffbox. We 
contacted appropriate State and Federal agencies, Ontario's Department 
of Fisheries and Oceans, elected officials, scientific organizations, 
and other interested parties and invited them to comment.
    During the comment period, we received a total of 16 comments from 
4 State agencies, 2 Federal agencies (3 comments in total), 4 groups, 
and 5 individuals, including 2 peer reviewers.

[[Page 8650]]

We have read and considered all comments received for substantive 
issues and new data regarding these two mussels. We updated the rule 
where it was appropriate. For readers' convenience, we have combined 
similar comments into single comments and responses.

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 five knowledgeable individuals with expertise on freshwater 
mollusks. 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 two of the peer reviewers. Both peer reviewers 
stated that they supported the proposal to list both species as 
endangered.

Peer Reviewer Comments

    (1) Comment: Peer reviewers provided updated information on rayed 
bean and snuffbox populations throughout the ranges of these species.
    Our Response: The updates have been incorporated into this final 
rule, where appropriate.
    (2) Comment: One peer reviewer provided information on recent 
genetic studies on snuffbox populations that suggests strong genetic 
isolation among populations.
    Our Response: The new information has been incorporated into the 
rule in the section discussing listing Factor E: Other Natural or 
Manmade Factors Affecting Their Continued Existence. This information 
is important because it provides additional support to the thought that 
many snuffbox populations are potentially below the effective 
population size required to maintain genetic heterogeneity and 
population viability.
    (3) Comment: One peer reviewer provided information on coal mining 
as a threat to both species throughout their ranges in Pennsylvania due 
to the discharge of acid mine drainage containing injurious substances 
(e.g., total dissolved solids and sulfates) from active and abandoned 
mines.
    Our Response: The new information has been incorporated into the 
rule in the section discussing listing Factor A: The Present or 
Threatened Destruction, Modification, or Curtailment of Their Habitat 
or Range. We find that this additional information provides additional 
support for our determination that the rayed bean and snuffbox have 
declined as a result of past destruction, modification, and or 
curtailment of their habitat or ranges and that this factor continues 
to threaten the continued existence of these species.
    (4) Comment: One peer reviewer provided information on a January 1, 
2011, State rulemaking in Pennsylvania that banned the use of all 
species of mussels as bait in Pennsylvania. Prior to this State 
rulemaking, individuals holding a valid Pennsylvania fishing license 
could collect up to 50 mussels per day for use as fish bait.
    Our Response: The information has been incorporated into the rule 
in the section discussing listing Factor D: The Inadequacy of Existing 
Regulatory Mechanisms.
    (5) Comment: One peer reviewer provided information on golden algae 
(Prymnesium parvum) as a threat to rayed bean and snuffbox populations 
in areas where water is withdrawn for shale gas drilling. Shale gas 
drilling has the potential to impact 23 of the 79 remaining snuffbox 
populations and 9 of the 32 remaining rayed bean populations.
    Our Response: The information has been incorporated into the rule 
in the sections discussing listing Factor A: The Present or Threatened 
Destruction, Modification, or Curtailment of Their Habitat or Range and 
Factor E: Other Natural or Manmade Factors Affecting Their Continued 
Existence.

Comments From States

    (6) Comment: The Pennsylvania Fish and Boat Commission and Virginia 
Department of Conservation and Recreation provided comments stating 
that they support the proposal to list both species.
    Our Response: These comments support the Service's proposal. We are 
grateful for support of the States and recognize that State 
partnerships are essential for the conservation of these species.
    (7) Comment: The Pennsylvania Fish and Boat Commission and the 
Wisconsin Department of Natural Resources provided information on State 
protection of these species in their respective States. The snuffbox 
was State listed as endangered in Pennsylvania on July 11, 2009. 
Listing of the rayed bean in Pennsylvania has been deferred, pending 
the results of additional survey efforts. The snuffbox has been listed 
as State endangered in Wisconsin since August 1, 1989.
    Our Response: These comments support the Service's proposal. We are 
grateful for support of the States and recognize that partnerships are 
essential for the conservation of these species.
    (8) Comment: The Pennsylvania Fish and Boat Commission, Wisconsin 
Department of Natural Resources Bureau of Endangered Species, Illinois 
Department of Natural Resources, and Virginia Department of 
Conservation and Recreation provided updated historical and current 
information on populations of both species in their States.
    Our Response: We appreciate the submission of the updated 
information. The updates have been incorporated into this rule, where 
appropriate.
    (9) Comment: The Pennsylvania Fish and Boat Commission provided 
information on a rayed bean reintroduction into the Duck River in 
Tennessee. In 2008, nearly 1,000 rayed bean were collected from the 
Allegheny River and reintroduced into the Duck River.
    Our Response: We appreciate the submission of the updated 
information. The information has been incorporated into this rule, 
where appropriate.
    (10) Comment: The Pennsylvania Fish and Boat Commission provided 
information on threats to both species from natural gas extraction from 
the Marcellus Shale formation. Current increases in natural gas 
extraction related to Marcellus Shale present a number of potential 
threats to the rayed bean and snuffbox, including the removal of large 
volumes of surface and groundwater for hydraulic fracturing (fracking), 
spills of untreated fracking flowback water, and development of 
infrastructure associated with natural gas extraction.
    Our Response: We appreciate the submission of information on the 
potential threats of natural gas extraction as it supports our 
assumption that this activity could threaten multiple populations of 
both species. The information has been incorporated into this rule in 
the sections discussing listing Factor A: The Present or Threatened 
Destruction, Modification, or Curtailment of Their Habitat or Range and 
Factor E: Other Natural or Manmade Factors Affecting Their Continued 
Existence.
    (11) Comment: The Wisconsin Department of Natural Resources Bureau 
of Endangered Species provided a comment regarding black carp 
(Mylopharyngodon piceus), a notorious molluscivore (mussel-eater), as a 
potential threat to these species due to its occurrence in the Illinois 
and Mississippi Rivers.
    Our Response: We appreciate the submission of the updated 
information. Information on the black carp as a threat to these species 
has been incorporated into this rule in the section discussing

[[Page 8651]]

listing Factor E: Other Natural or Manmade Factors Affecting Their 
Continued Existence.
    (12) Comment: The Wisconsin Department of Natural Resources Bureau 
of Endangered Species provided a comment that the proposed rule did not 
discuss the significance of the host fish and that if the host fish are 
negatively impacted, the mussels are also negatively impacted.
    Our Response: Discussion on the role of the host fish was included 
in the proposed rule in the Life History section and in the discussion 
of listing Factor A: The Present or Threatened Destruction, 
Modification, or Curtailment of Their Habitat or Range and Factor E: 
Other Natural or Manmade Factors Affecting Their Continued Existence.
    (13) Comment: The Virginia Department of Conservation and 
Recreation was not aware of multiple historical records of the rayed 
bean in the Clinch River in Virginia.
    Our Response: Seven records of the rayed bean from the Clinch River 
can be found at the Ohio State University Museum of Biological 
Diversity (OSUM) and the Museum of Fluviatile Mollusks (MFM). Two OSUM 
records exist for the Clinch River from 1965 in Russell and Scott 
Counties, Virginia. Three OSUM records also exist for the Clinch River 
in 1963 in Russell, Wise, and Scott Counties, Virginia. MFM holds two 
records for the rayed bean from the Clinch River from 1953 and 1955.

Comments From Federal Agencies

    (14) Comment: The Natural Resources Conservation Service and Genoa 
National Fish Hatchery provided comments supporting the proposal to 
list both species.
    Our Response: These comments support the Service's proposal. We are 
grateful for support of these Federal agencies and recognize that 
partnerships are essential for the conservation of these species.
    (15) Comment: The Natural Resources Conservation Service provided 
comments encouraging agency partnerships with the Service to conserve 
both species.
    Our Response: The Service seeks partnerships with all interested 
parties to conserve these species. We encourage the Natural Resources 
Conservation Service to be an active participant in the recovery 
planning and implementation process for these species.
    (16) Comment: The Genoa National Fish Hatchery provided information 
on propagation of the snuffbox and recommends propagation as a tool for 
recovery of the species.
    Our Response: The data will be incorporated into recovery planning 
for these species. We encourage the Genoa National Fish Hatchery to be 
an active participant in the recovery planning and implementation 
process.

Comments From Groups

    (17) Comment: The Service received comments from three groups 
supporting the proposal to list both species.
    Our Response: These comments support the Service's proposal. We are 
grateful for support of these non-governmental organizations and 
recognize that partnerships are essential for the conservation of these 
species.
    (18) Comment: Pennsylvania Biological Survey, Western Pennsylvania 
Conservancy, and The Nature Conservancy provided updated historical and 
current information on populations of both species in Pennsylvania, 
Virginia, and West Virginia.
    Our Response: We appreciate the submission of the updated 
information. The updates have been incorporated into this rule, where 
appropriate.
    (19) Comment: The Nature Conservancy, Pennsylvania Biological 
Survey, and Western Pennsylvania Conservancy provided information on 
threats to both species from natural gas extraction from the Marcellus 
Shale formation.
    Our Response: We appreciate the submission of information on the 
potential threats of natural gas extraction as it supports our 
assumption that this activity could threaten multiple populations of 
both species. The information has been incorporated into this rule in 
the sections discussing listing Factor A: The Present or Threatened 
Destruction, Modification, or Curtailment of Their Habitat or Range and 
Factor E: Other Natural or Manmade Factors Affecting Their Continued 
Existence.
    (20) Comment: Western Pennsylvania Conservancy provided information 
on the potential future threats to both species from natural gas 
extraction from the Utica Shale formation within the French Creek 
drainage.
    Our Response: We appreciate the submission of information on the 
potential threats of natural gas extraction as it supports our 
assumption that this activity could threaten multiple populations of 
both species. The information has been incorporated into this rule in 
the sections discussing listing Factor A: The Present or Threatened 
Destruction, Modification, or Curtailment of Their Habitat or Range and 
Factor E: Other Natural or Manmade Factors Affecting Their Continued 
Existence.
    (21) Comment: American Rivers provided the Service with a list of 
14 mussel references that reported on the species' ranges and 
populations.
    Our Response: We appreciate the submission of the updated 
information. Information from these references has been incorporated 
into this rule, where appropriate.
    (22) Comment: Pennsylvania Biological Survey provided information 
on sand and gravel extraction from the Allegheny River's navigational 
pools as a threat to the rayed bean.
    Our Response: We appreciate the submission of information on this 
threat to the Allegheny River rayed bean population. The information 
has been incorporated into this rule in the section discussing listing 
Factor A: The Present or Threatened Destruction, Modification, or 
Curtailment of Their Habitat or Range.
    (23) Comment: The Western Pennsylvania Conservancy provided a 
comment regarding black carp (Mylopharyngodon piceus) as a potential 
threat to these species as this species of carp specializes in the 
consumption of mollusks (snails and mussels).
    Our Response: We appreciate the submission of information on this 
threat to mussels. Information on the black carp as a threat to these 
species has been incorporated into this rule in the section discussing 
listing Factor E: Other Natural or Manmade Factors Affecting Their 
Continued Existence.
    (24) Comment: The Nature Conservancy provided information on 
current and foreseeable threats to both species from mountaintop 
removal mines in the Elk River drainage in West Virginia.
    Our Response: We appreciate the submission of information on this 
threat to the Elk River snuffbox and rayed bean populations. The 
information has been incorporated into this rule in the section 
discussing listing Factor A: The Present or Threatened Destruction, 
Modification, or Curtailment of Their Habitat or Range.
    (25) Comment: The Nature Conservancy provided information on 
current threats to both species from old deep coal mining operations 
still affecting water quality in some Elk River tributaries in West 
Virginia.
    Our Response: We appreciate the submission of information on this 
threat to the Elk River snuffbox and rayed bean populations. The 
information has been incorporated into this rule in the section 
discussing listing Factor A: The Present or Threatened Destruction,

[[Page 8652]]

Modification, or Curtailment of Their Habitat or Range.

Comments From Individuals

    (26) Comment: The Service received two comments from individuals 
supporting the proposal to list both species.
    Our Response: We are grateful for support of private citizens and 
recognize that partnerships are essential for the conservation of these 
species. These comments support the Service's proposal.
    (27) Comment: The Service received information from one individual 
providing updated information on a population of snuffbox in Tygarts 
Creek in Kentucky.
    Our Response: We appreciate the submission of the updated 
information. The information has been incorporated into this rule, 
where appropriate.

Summary of Information Pertaining to the Five Factors

    Section 4 of the Act (16 U.S.C. 1533), and its implementing 
regulations at 50 CFR part 424, set forth the procedures for adding 
species to the Federal Lists of Endangered and Threatened Wildlife and 
Plants. Under section 4(a)(1) of the Act, we may determine a species to 
be endangered or threatened due to one or more of the following five 
factors: (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. Listing actions may be warranted based on any of 
the above threat factors, singly or in combination. Each of these 
factors is discussed below.

A. The Present or Threatened Destruction, Modification, or Curtailment 
of Their Habitat or Range

    Both species have experienced significant curtailment of their 
occupied habitats (see Background, above). The rayed bean has been 
eliminated from about 73 percent of the streams in which it 
historically occurred. This species has also been eliminated from long 
reaches of former habitat in hundreds of miles of the Maumee, Ohio, 
Wabash, and Tennessee Rivers, and from numerous stream reaches in their 
tributaries. The snuffbox has been eliminated from about 62 percent of 
the streams in which it historically occurred. Furthermore, extant 
populations, with few exceptions, are highly fragmented and restricted 
to short reaches. Available records indicate that 32 percent of streams 
considered to harbor extant populations of the snuffbox are represented 
by only one or two recent L or FD individuals. The primary cause of 
range curtailment for both species has been modification and 
destruction of river and stream habitats, primarily by the construction 
of impoundments.
    Impoundment--Impoundments result in the dramatic modification of 
riffle and shoal habitats and a resulting loss of mussel resources, 
especially in larger rivers. Neves et al. (1997, pp. 63-64) and Watters 
(2000, pp. 261-262) reviewed the specific effects of impoundments on 
freshwater mollusks. Dams interrupt a river's ecological processes by 
modifying flood pulses; controlling impounded water elevations; 
altering water flow, sediments, nutrients, and energy inputs and 
outputs; increasing depth; decreasing habitat heterogeneity; decreasing 
stability due to subsequent sedimentation; blocking host fish passage; 
and isolating mussel populations from fish hosts. Even small, low-head 
dams can have some of these effects on mussels.
    The reproductive process of riverine mussels is generally disrupted 
by impoundments, making the rayed bean and snuffbox unable to 
successfully reproduce and recruit under reservoir conditions. 
Population losses due to impoundments have likely contributed more to 
the decline and imperilment of the rayed bean and snuffbox than has any 
other single factor. Neither species occurs in reservoirs lacking 
riverine characteristics, although both persist in some reaches of 
large rivers with dams (Ohio River and Allegheny River), they are 
restricted to sections retaining riverine characteristics (generally 
tailwaters). Both species, however, historically occurred in the wave-
washed shallows of several glacial lakes, an environment very different 
from that found in impoundments.
    Stream habitat throughout major portions of the range of both 
species has been impounded. The majority of the Tennessee and 
Cumberland River mainstems and many of their largest tributaries are 
now impounded. There are 36 major dams located in the Tennessee River 
system, and about 90 percent of the Cumberland River downstream of 
Cumberland Falls is either directly impounded by U.S. Army Corps of 
Engineers (Corps) structures or otherwise impacted by cold tailwater 
released from dams. Watters (2000, pp. 262-263) summarizes the 
tremendous loss of mussel species from various portions of the 
Tennessee and Cumberland River systems. The rayed bean has been 
eliminated from the Tennessee River system and the snuffbox, once 
widespread throughout both systems, now persists in only five Tennessee 
River tributaries and one Cumberland River tributary.
    This impoundment scenario is similar in many other parts of the 
range of the rayed bean and snuffbox, and includes numerous 
navigational locks and dams (Ohio, Allegheny, Muskingum and Green 
Rivers), major dams (Shenango, Elk, Walhonding, Scioto, Little Miami, 
Green, Nolin, Barren, Tippecanoe, Wabash, Mississinewa, Salamonie, and 
Duck Rivers), and low-head dams (Pine, Belle, Clinton, Huron, Maumee, 
Auglaize, Sandusky, Mahoning, Tuscarawas, Walhonding, Scioto, 
Olentangy, Wabash, Mississinewa, East Fork White, West Fork White, and 
Duck Rivers; and Middle Island, Big Walnut, Alum, Big Darby, Little 
Darby, Sugar, and Richland Creeks) that have contributed to the loss of 
the species' habitat. Sediment accumulations behind dams of all sizes 
generally preclude the occurrence of the rayed bean and snuffbox 
(Butler 2002, p. 22; Butler 2007, p. 73).
    Dredging and Channelization--Dredging and channelization activities 
have profoundly altered riverine habitats nationwide. Hartfield (1993, 
pp. 131-141), Neves et al. (1997, pp. 71-72), and Watters (2000, pp. 
268-269) reviewed the specific effects of channelization on freshwater 
mollusks. Channelization impacts a stream's physical (accelerated 
erosion, reduced depth, decreased habitat diversity, geomorphic 
instability, and riparian canopy loss) and biological (decreased fish 
and mussel diversity, changed species composition and abundance, 
decreased biomass, and reduced growth rates) characteristics (Hartfield 
1993, p. 131; Hubbard et al. 1993, pp. 136-145). Channel construction 
for navigation has been shown to increase flood heights (Belt 1975, p. 
189). This is partially attributed to a decrease in stream length and 
increase in gradient (Hubbard et al. 1993, p. 137). Flood events may 
thus be exacerbated, conveying into streams large quantities of 
sediment, potentially with adsorbed contaminants. Channel maintenance 
may result in profound impacts downstream (Stansbery 1970, p. 10), such 
as increases in turbidity and sedimentation, which may smother benthic 
(bottom-dwelling) organisms such as the rayed bean and snuffbox.
    The only known rayed bean populations that remain in navigation 
channels are in the upper four navigation pools of the Allegheny River. 
Sand and gravel extraction from these

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pools continues to occur, and a recent study found evidence that 
habitat alteration and loss from sand and gravel dredging has had an 
adverse effect on the mussel fauna in the navigation pools of the 
Allegheny River (Walsh 2010, pers. comm.; Smith and Meyer 2010, p. 
556). Activities associated with navigation channels may have 
contributed to the elimination of the rayed bean from the Ohio, lower 
Allegheny, and Muskingum Rivers, and potentially others. Channel 
maintenance operations for barge navigation have impacted habitat for 
the snuffbox in several large rivers. Impacts associated with barge 
traffic, which include construction of fleeting areas, mooring cells, 
docking facilities, and propeller wash, also disrupt habitat. 
Navigation maintenance activities may continue to adversely affect this 
species in the upper Ohio River. Hundreds of miles of streams 
containing rayed bean (Olentangy, Salamonie, Mississinewa, Vermilion, 
North Fork Vermilion, Embarras Rivers) and snuffbox (Grand, Kankakee, 
Sangamon, Kaskaskia, Olentangy, Salamonie, Mississinewa, Eel, 
Vermilion, North Fork Vermilion, Embarras, Paint Rock, and St. Francis 
Rivers; and Tonawanda, Killbuck, Chickamauga, and Bear Creeks) were 
dredged and channelized decades ago, and some populations have been 
eliminated from these streams. The entire length of the Kankakee River 
in Indiana was channelized by 1917. In addition, hundreds of drains 
(formed from ditching low-gradient creeks and swales) were created 
around 100 years ago in Illinois, Michigan, and other midwestern 
States. Stream channelizations were attempts to reduce flooding, drain 
low-lying areas, and ``improve'' storm flow runoff.
    Chemical Contaminants--Chemical contaminants are ubiquitous 
throughout the environment and are considered a major threat in the 
decline of freshwater mussel species (Cope et al. 2008, p. 451; Richter 
et al. 1997, p. 1081; Strayer et al. 2004, p. 436; Wang et al. 2007, p. 
2029). Chemicals enter the environment through both point and nonpoint 
discharges, including spills, industrial sources, municipal effluents, 
and agricultural runoff. These sources contribute organic compounds, 
heavy metals, pesticides, and a wide variety of newly emerging 
contaminants to the aquatic environment. As a result, water and 
sediment quality can be degraded to the extent that mussel populations 
are adversely impacted.
    Chemical spills can be especially devastating to mussels because 
they may result in exposure of a relatively immobile species to 
extremely elevated concentrations that far exceed toxic levels and any 
water quality standards that might be in effect. Some notable spills 
that released large quantities of highly concentrated chemicals 
resulting in mortality to mussels include: Massive mussel kills on the 
Clinch River at Carbo, Virginia, occurred from a power plant alkaline 
fly ash pond spill in 1967 and a sulfuric acid spill in 1970 (Crossman 
et al. 1973, p. 6); approximately 18,000 mussels of several species 
including 750 individuals from three endangered mussel species were 
eliminated from the upper Clinch River near Cedar Bluff, Virginia, in 
1998, when an overturned tanker truck released 1,600 gallons (6,056 
liters) of a chemical used in rubber manufacturing (Jones et al. 2001, 
p. 20; Schmerfeld 2006, p. 12); and an ongoing release starting in 1999 
of sodium dimethyl dithiocarbamate, a chemical used to reduce and 
precipitate hexachrome, impacted approximately 10 river miles (16 km) 
of the Ohio River and resulted in an estimated loss of one million 
mussels, including individuals from two federally listed species 
(DeVault 2009, pers. comm.; Clayton 2008, pers. comm.). These are not 
the only instances where chemical spills have resulted in the loss of 
high numbers of mussels (Brown et al. 2005, p. 1457; Neves 1991, p. 
252; Jones et al. 2001, p. 20; Schmerfeld 2006, pp. 12-13), but are 
provided as examples of the serious threat chemical spills pose to 
mussel species. The rayed bean and snuffbox are especially threatened 
by chemical spills because these spills can occur anywhere there are 
highways with tanker trucks, industries, or mines and where these 
overlap with rayed bean and snuffbox distribution. For example, a gas 
station close to the flood zone upstream of the rayed bean population 
in Cassadaga Creek makes the rayed bean extremely susceptible to a 
stochastic event, such as a toxic chemical spill.
    Exposure of mussels to lower concentrations of contaminants more 
likely to be found in aquatic environments can also adversely affect 
mussels and result in the decline of freshwater mussel species. Such 
concentrations may not be immediately lethal, but, over time, can 
result in mortality, reduced filtration efficiency, reduced growth, 
decreased reproduction, changes in enzyme activity, and behavioral 
changes to all mussel life stages. Frequently, procedures which 
evaluate the `safe' concentration of an environmental contaminant (for 
example, national water quality criteria) do not have data for 
freshwater mussel species or exclude data that is available for 
freshwater mussels (March et al. 2007, pp. 2066-2067, 2073).
    Current research is now starting to focus on the contaminant 
sensitivity of freshwater mussel glochidia and newly-released juvenile 
mussels (Goudreau et al. 1993, pp. 219-222; Jacobson et al. 1997, p. 
2390; Wang, 2007a, pp. 2041-2046; Valenti 2005, pp. 1244-1245; Valenti 
2006, pp. 2514-2517; March 2007, pp. 2068-2073) and juveniles (Bartsch 
et al. 2003, p. 2561; Augspurger et al. 2003, p. 2569; Mummert et al. 
2003, p. 2549, Wang, 2007b, pp. 2053-2055, Wang, 2007a, pp. 2041-2046, 
Valenti 2005, pp. 1244-1245; Valenti 2006, pp. 2514-2517; March 2007, 
pp. 2068-2073) to such contaminants as ammonia, metals, chlorine, and 
pesticides. The toxicity information presented in this section focuses 
on recent water-only laboratory acute (sudden and severe exposure) and 
chronic (prolonged or repeated exposure) toxicity tests with early life 
stages of freshwater mussels using the standard testing methodology 
published by the American Society for Testing and Materials (ASTM) 
(American Society for Testing and Materials 2008, pp. 1442-1493). Use 
of this standard testing method generates consistent, reliable toxicity 
data with acceptable precision and accuracy (Wang et al. 2007a, p. 
2035) and was used for toxicity tests on ammonia, copper, chlorine, and 
select pesticides (Augspurger et al. 2007, p. 2025; Bringolf et al. 
2007a, p. 2087; Bringolf et al. 2007c, p. 2101; Wang et al. 2007a, p. 
2029; Wang et al. 2007b, p. 2036; Wang et al. 2007c, p. 2048). Use of 
these tests has documented that while mussels are sensitive to some 
contaminants, they are not universally sensitive to all contaminants 
(Augspurger et al. 2007, pp. 2025-2026).
    One chemical that is particularly toxic to early life stages of 
mussels is ammonia. Sources of ammonia include agricultural sources 
(animal feedlots and nitrogenous fertilizers), municipal wastewater 
treatment plants, and industrial waste (Augspurger et al. 2007, p. 
2026), as well as precipitation and natural processes (decomposition of 
organic nitrogen) (Goudreau et al. 1993, p. 212; Hickey and Martin 
1999, p. 44; Augspurger et al. 2003, p. 2569; Newton 2003, p. 1243). 
Therefore, ammonia is considered a limiting factor for survival and 
recovery of some mussel species due to its ubiquity in aquatic 
environments and high level of toxicity, and because the highest 
concentrations typically occur in sediment pore water where mussels are 
found (Augspurger et al. 2003, p. 2574). In addition, studies

[[Page 8654]]

have shown that ammonia concentrations increase with increasing 
temperature and low-flow conditions (Cherry et al. 2005, p. 378; Cooper 
et al. 2005, p. 381), which may be exacerbated by the effects of 
climate change, and may cause ammonia to become more problematic for 
juvenile mussels. The Environmental Protection Agency's (EPA's) 
established ammonia water quality criteria (EPA 1985, pp. 94-99) may 
not be protective of mussels (Augspurger et al. 2003, p. 2572; Sharpe 
2005, p. 28) under current and future climate conditions.
    Mussels are also affected by metals (Keller and Zam 1991, p. 543), 
such as cadmium, chromium, copper, mercury, and zinc, which can 
negatively affect biological processes such as growth, filtration 
efficiency, enzyme activity, valve closure, and behavior (Naimo 1995, 
pp. 351-355; Keller and Zam 1991, p. 543; Jacobson et al. 1997, p. 
2390; Valenti et al. 2005, p. 1244). Metals occur in industrial and 
wastewater effluents and are often a result of atmospheric deposition 
from industrial processes and incinerators. Glochidia and juvenile 
freshwater mussels have recently been studied to determine the acute 
and chronic toxicity of copper to these life stages (Wang 2007a, pp. 
2036-2047; Wang 2007b, pp. 2048-2056). The chronic values determined 
for copper ranged from 8.5 to 9.8 micrograms per liter (ug/L) for 
survival and from 4.6 to 8.5 ug/L for growth of juveniles. These 
chronic values are below the EPA's 1996 chronic water quality criterion 
of 15 ug/L (hardness 170 mg/L) for copper (Wang 2007b, pp. 2052-2055). 
March (2007, pp. 2066, 2073) identifies that copper water quality 
criteria and modified State water quality standards may not be 
protective of mussels.
    Mercury is another heavy metal that has the potential to negatively 
affect mussel populations, and it is receiving attention due to its 
widespread distribution and potential to adversely impact the 
environment. Mercury has been detected throughout aquatic environments 
as a product of municipal and industrial waste and atmospheric 
deposition from coal-burning plants. One study evaluated the 
sensitivity of early life stages of mussels to mercury (Valenti 2005, 
p. 1242). This study determined that, for the mussel species used 
(rainbow mussel, Villosa iris), glochidia were more sensitive to 
mercury than were juvenile mussels, with the median lethal 
concentration value of 14 ug/L compared to 114 ug/L for the juvenile 
life stage. The chronic toxicity tests conducted determined that 
juveniles exposed to mercury greater than or equal to 8 ug/L exhibited 
reduced growth. These observed toxicity values are greater than EPA's 
Criteria Continuous Concentration and Criteria Maximum Concentration, 
which are 0.77 ug/L and 1.4 ug/L, respectively. Based on these data, we 
find that EPA's water quality standards for mercury should be 
protective of juvenile mussels and glochidia, except in cases of 
illegal dumping, permit violations, or spills. However, impacts to 
mussels from mercury toxicity may be occurring in some streams. 
According to the National Summary Data reported by States to the EPA, 
3,770 monitored waters do not meet EPA standards for mercury in the 
United States (http://iaspub.epa.gov, accessed 6/28/2010). Acute 
mercury toxicity was determined to be the cause of extirpation of a 
diverse mussel fauna for a 70-mile (112-km) portion of the North Fork 
Holston River (Brown et al. 2005, pp. 1455-1457).
    In addition to ammonia, agricultural sources of chemical 
contaminants include two broad categories that have the potential to 
adversely impact mussel species: nutrients and pesticides. Nutrients 
(such as nitrogen and phosphorus) can impact streams when their 
concentrations reach levels that cannot be assimilated, a condition 
known as over-enrichment. Nutrient over-enrichment is primarily a 
result of runoff from livestock farms, feedlots, and heavily fertilized 
row crops (Peterjohn and Correll 1984, p. 1471). Over-enriched 
conditions are exacerbated by low-flow conditions, such as those 
experienced during typical summer-season flows and that might occur 
with greater frequency and magnitude as a result of climate change. 
Bauer (1988, p. 244) found that excessive nitrogen concentrations can 
be detrimental to the adult freshwater pearl mussel (Margaritifera 
margaritifera), as was evident by the positive linear relationship 
between mortality and nitrate concentration. Also, a study of mussel 
lifespan and size (Bauer 1992, p. 425) showed a negative correlation 
between growth rate and eutrophication, and longevity was reduced, as 
the concentration of nitrates increased. Nutrient over-enrichment can 
result in an increase in primary productivity, and the subsequent 
respiration depletes dissolved oxygen levels. This may be particularly 
detrimental to juvenile mussels that inhabit the interstitial spaces in 
the substrate where lower dissolved oxygen concentrations are more 
likely than on the sediment surface where adults tend to live (Sparks 
and Strayer 1998, pp. 132-133).
    Elevated concentrations of pesticides frequently occur in streams 
due to pesticide runoff, overspray application to row crops, and lack 
of adequate riparian buffers. Agricultural pesticide applications often 
coincide with the reproductive and early life stages of mussels, and 
thus impacts to mussels due to pesticides may be increased (Bringolf et 
al. 2007a, p. 2094). Little is known regarding the impact of currently 
used pesticides to freshwater mussels even though some pesticides, such 
as glyphosate (Roundup[supreg]), are used globally. Recent studies 
tested the toxicity of glyphosate, its formulations, and a surfactant 
(MON 0818) used in several glyphosate formulations, to early life 
stages of the fatmucket (Lampsilis siliquoidea), a native freshwater 
mussel (Bringolf et al. 2007a, p. 2094). Studies conducted with 
juvenile mussels and glochidia determined that the surfactant (MON 
0818) was the most toxic of the compounds tested and that fatmucket 
glochidia were the most sensitive organism tested to date (Bringolf et 
al. 2007a, p. 2094). Roundup[supreg], technical grade glyphosate 
isopropylamine salt, and isopropylamine were also acutely toxic to 
juveniles and glochidia (Bringolf et al. 2007a, p. 2097). The impacts 
of other pesticides, including atrazine, chlorpyrifos, and permethrin, 
on glochidia and juvenile life stages have also recently been studied 
(Bringolf et al. 2007b, p. 2101). This study determined that 
chlorpyrifos was toxic to both fatmucket glochidia and juveniles 
(Bringolf et al. 2007b, p. 2104). The above results indicate the 
potential toxicity of commonly applied pesticides and the threat to 
mussel species as a result of the widespread use of these pesticides. 
All of these pesticides are commonly used throughout the range of the 
rayed bean and snuffbox.
    A potential, but undocumented, threat to freshwater mussel species, 
including rayed bean and snuffbox, are contaminants referred to as 
``emerging contaminants'' that are being detected in aquatic ecosystems 
at an increasing rate. Pharmaceuticals, hormones, and other organic 
contaminants have been detected downstream from urban areas and 
livestock production (Kolpin et al. 2002, p. 1202). A large potential 
source of these emerging contaminants is wastewater being discharged 
through both permitted (National Pollutant Discharge Elimination System 
(NPDES)) and nonpermitted sites throughout the country. Permitted 
discharge sites are ubiquitous in watersheds with rayed bean and 
snuffbox populations, providing ample opportunities for contaminants to 
impact the species (for

[[Page 8655]]

example, there are more than 250 NPDES sites in the Meramec River, 
Missouri system, which harbors a declining population of snuffbox) 
(Roberts and Bruenderman 2000, p. 78).
    The information presented in this section represents some of the 
threats from chemical contaminants that have been documented, both in 
the laboratory and field, and demonstrates that chemical contaminants 
pose a substantial threat to the rayed bean and snuffbox. This 
information indicates the potential for contaminants to contribute to 
declining rayed bean and snuffbox populations--from spills that are 
immediately lethal to species, to chronic contaminant exposure, which 
results in death, reduced growth, or reduced reproduction of rayed bean 
and snuffbox.
    Mining--The low pH commonly associated with coal mine runoff can 
reduce glochidial encystment rates, thus impacting mussel recruitment 
(Huebner and Pynn[ouml]nen 1992, p. 2350). Additionally, adverse 
impacts from heavy-metal-rich drainage from coal mining and associated 
sedimentation have been documented in portions of historical rayed bean 
and snuffbox habitat in the upper Ohio River system in western 
Pennsylvania (Ortmann 1909c, p. 97), West Virginia, and southeastern 
Ohio. Likewise, coal mining has impacted rayed bean habitat in the 
upper Tennessee River system, Virginia (Kitchel et al. 1981, p. 21), 
and snuffbox habitat in eastern Kentucky (lower Ohio and Mississippi 
River systems in southeastern Illinois and western Kentucky; upper 
Cumberland River system in southeastern Kentucky and northeastern 
Tennessee; and upper Tennessee River system in southwestern Virginia) 
(Ortmann 1909c, p. 103; Neel and Allen 1964, pp. 428-430; Kitchel et 
al. 1981, p. 21; Anderson et al. 1991, pp. 6-7; Gordon 1991, p. 2; 
Bogan and Davis 1992, p. 2; Layzer and Anderson 1992, pp. 91-94; 
Ahlstedt and Tuberville 1997, p. 75; Milam et al. 2000, p. 53; Warren 
and Haag 2005, p. 1394). Acid mine drainage was implicated in the 
mussel die-off in the Little South Fork Cumberland River, Kentucky 
(Anderson et al. 1991, pp. 6-7; Layzer and Anderson, 1992, p. 94; 
Ahlstedt and Saylor 1995-96, pp. 92-93; Warren and Haag 2005, p. 1394). 
Tailings (the materials left over after extracting the desirable 
component of an ore) pond failures have also impacted aquatic resources 
(Powell River, Virginia; Butler 2007, p. 83). A decline of the snuffbox 
and other imperiled mussels in the Powell River was blamed on coal-
mining impacts (Ahlstedt and Tuberville 1997, p. 75). Increased mining 
activities in the upper Clinch River system are resulting in 
``blackwater'' events (Jones and Neves 2004, p. 2). Anecdotal evidence 
suggests that coal fines (very small coal particles) are increasing in 
the Clinch River reach that harbors a stronghold snuffbox population 
(Butler 2007, p. 84). A coal-fired power plant planned for the upper 
Clinch River in Virginia would further increase mining in the Clinch 
and Powell watersheds.
    Currently, active coal mining activities occur in the range of both 
species in the Elk River in West Virginia and Dunkard Creek, a 
tributary to the Monongahela River that straddles the Pennsylvania and 
West Virginia State lines (Douglas 2010, pers. comm.). The coal mining 
threat to the rayed bean and snuffbox in the Elk River in West Virginia 
includes new and scheduled-to-expand mountaintop removal mines in large 
tributaries to the Elk (Cimarolli and Beaty 2011, pers. comm.). 
Additionally, deep mining operations are still affecting water quality 
in some Elk River tributaries in West Virginia and in Dunkard Creek 
(Cimarolli and Beaty 2011, pers. comm.; Welte 2001, pers. comm.). In 
2009, a golden algae bloom caused an aquatic life kill in 43 mi (69 km) 
of Dunkard Creek, eliminating the stream's mussel community, which 
included the snuffbox (USEPA 2009, p. 5). The algal bloom was 
associated with a spike in conductivity (dissolved impurities) thought 
to be associated with a discharge from an underground mine (USEPA 2009, 
p. 5; Anderson and Kreeger 2010, p. 9). If coal mining activities are 
reinitiated in western Pennsylvania, they could also become a threat to 
populations of both species in the lower French Creek and the Allegheny 
River.
    Instream and alluvial (clay, silt, sand, or other material 
deposited by running water) gravel mining has been implicated in the 
destruction of several mussel populations (Hartfield 1993, pp. 135-136; 
Brown and Curole 1997, pp. 239-240). Negative impacts associated with 
gravel mining include stream channel modifications (altered habitat, 
disrupted flow patterns, sediment transport), water quality 
modifications (increased turbidity, reduced light penetration, 
increased temperature), macroinvertebrate population changes 
(elimination, habitat disruption, increased sedimentation), and changes 
in fish populations (impacts to spawning and nursery habitat, food web 
disruptions) (Kanehl and Lyons 1992, pp. 26-27; Roell 1999, p. 5). 
Gravel mining may continue to be a localized threat to rayed bean and 
snuffbox populations (Allegheny River (Pennsylvania), Kankakee, 
Bourbeuse, Walhonding, Elk (Tennessee), and Strawberry Rivers; Big 
Darby and Buck (Kentucky) Creeks).
    Other mining activities that impact snuffbox populations include 
mining for metals (lead, cadmium, zinc) in Missouri. Mining has been 
implicated in the decline of mussels from the upper St. Francis River 
(Hutson and Barnhart 2004, pp. 86-87). Lead and barite mining is common 
in the Big River, a Meramec River tributary. A tailings-pond blowout 
discharged 81,000 cubic yards of mine tailings in 1977 that impacted 
approximately 80 river mi (129 river km) (Buchanan 1980, p. 9; Roberts 
and Bruenderman 2000, p. 24). As of 2000, high levels of heavy metals 
were still detected in the system (Roberts and Bruenderman 2000, p. 24) 
and may continue to hinder stream recovery. Forty-five tailings ponds 
and numerous tailings piles remain in the watershed (Roberts and 
Bruenderman 2000, p. 24).
    Oil and gas production may have contributed to the decline of the 
rayed bean and snuffbox in certain drainages (Sangamon River in the 
upper Mississippi River system; Slippery Rock and Connoquenessing 
Creeks in the upper Ohio River system; Green, Kentucky, Salamonie, and 
Mississinewa Rivers in the lower Ohio River system) (Ortmann 1909c, 
p.104; Schanzle and Cummings 1991, p. 1; ESI 1995, p. 39; Cicerello 
1999, p. 11). Pollutants include brines (salt water), high levels of 
potassium, and numerous organic compounds (Imlay 1971, p. 39). An 
increasing demand for domestic energy resources is expected to 
accelerate oil and gas exploration in certain rayed bean and snuffbox 
streams in the foreseeable future.
    Oil and natural gas resources are present in some of the watersheds 
that are known to support rayed bean and snuffbox, including the 
Allegheny River, Middle Island Creek, and the Elk River. Exploration 
and extraction of these energy resources can result in increased 
siltation, fluctuating levels of water flow, and altered water quality 
even at a distance from the mine or well field. Suspended sediments can 
interfere with mussel respiration and feeding. Low water levels can 
expose mussels to the atmosphere, which can result in stress and 
mortality, especially during cold or hot conditions. Rayed bean and 
snuffbox habitat in larger streams can be threatened by the cumulative 
effects of multiple mines and well fields (USFWS 2008, p. 11).
    Oil and gas resources extraction has increased dramatically in 
recent years,

[[Page 8656]]

particularly in Pennsylvania and West Virginia (USFWS 2008, p. 10; 
Urban 2010, pers. comm.; Walsh 2010, pers. comm.; Bier 2011, pers. 
comm.). Although oil and gas extraction generally occurs away from the 
river, extensive road networks are required to construct and maintain 
wells. These road networks frequently cross or occur near tributaries, 
contributing sediment to the receiving waterway. In addition, the 
construction and operation of wells may result in the discharge of 
brine (salt water), which can cause acute toxicity and mortality of 
mussels if mussel tolerance levels are exceeded (Anderson and Kreeger 
2010, p. 8). Point source discharges are typically regulated; however, 
nonpoint inputs such as silt and other contaminants may not be 
sufficiently regulated, particularly those originating some distance 
from a waterway. In 2006, the Pennsylvania Department of Environmental 
Protection issued more than 3,700 permits for oil and gas wells and 98 
citations for permit violations at 54 wells (Hopey 2007, p. 1; USFWS, 
2008, p. 12).
    One issue of particular concern is the increase in natural gas 
extraction from the Marcellus Shale formation. The Marcellus formation 
is a black shale that is found from southern New York, across 
Pennsylvania, and into western Maryland, West Virginia, and eastern 
Ohio (Marcellus Formation 2011, p. 2). This shale contains significant 
quantities of natural gas that is now being extracted using new 
drilling technologies and because of an increased demand for natural 
gas (Soeder and Kappel 2009, p. 1). In order to extract the natural gas 
from the shale, large volumes of water are needed to drill and 
hydraulically fracture the rock. After the drilling and fracturing is 
completed, the water must be removed from the well before the gas can 
flow. Extensive water withdrawals associated with the Marcellus Shale 
wells can dewater mussel beds and reduce habitat suitability (Douglas 
2010, pers. comm.). Concerns about the availability of water supplies 
needed for gas production and questions about wastewater disposal have 
been raised by water-resource agencies and citizens throughout the 
Marcellus Shale gas development region (Soeder and Kappel 2009, pp. 3-
4).
    Below the Marcellus Shale lies the Utica Shale, which also holds a 
significant amount of natural gas (http://geology.com 2011). The Utica 
Shale is thicker than the Marcellus, it is more geographically 
extensive, and it has already proven its ability to support commercial 
production (http://geology.com 2011). Extraction of natural gas from 
the Utica Shale would employ the same drilling and fracturing methods 
as with Marcellus Shale and, therefore, the same potential impacts on 
surface water. Natural gas extraction in the Marcellus and Utica Shales 
has the potential to negatively impact rayed bean and snuffbox 
populations throughout New York, Pennsylvania, West Virginia, eastern 
Ohio, and Ontario, Canada.
    Siltation--Excessive sedimentation affects an estimated 28 percent 
of all U.S. streams (Judy et al. 1984, p. 38), including the majority 
of the streams with extant rayed bean and snuffbox populations. 
Sedimentation has been implicated in the decline of mussel populations 
nationwide and is a threat to rayed bean and snuffbox (Kunz 1898, p. 
328; Ellis 1936, pp. 39-40; Marking and Bills 1979, p. 204; Vannote and 
Minshall 1982, p. 4105-4106; Dennis 1984, p. 212; Wolcott and Neves 
1990, pp. 74-75; Brim Box 1999, p. 79; Fraley and Ahlstedt 2000, p. 
194; Poole and Downing 2004, pp. 119-120). Specific biological impacts 
include reduced feeding and respiratory efficiency due to clogged 
gills, disrupted metabolic processes, reduced growth rates, limited 
burrowing activity, and physical smothering (Ellis 1936, pp. 39-40; 
Stansbery 1971, p. 6; Imlay 1972, p. 76; Marking and Bills 1979, p. 
210; Vannote and Minshall 1982, p. 4105; Waters 1995, p. 7).
    Studies indicate that excessive sediment level impacts are 
sublethal, with detrimental effects not immediately apparent (Brim Box 
and Mossa 1999, p. 101). Physical habitat effects include altered 
suspended and bed material loads, and bed sediment composition 
associated with increased sediment production and run-off; clogged 
interstitial habitats and reduced interstitial flow rates and dissolved 
oxygen levels; changed channels in form, position, and degree of 
stability; altered depth or width-depth ratio that affects light 
penetration and flow regime; aggraded (filling) or degraded (scouring) 
channels; and changed channel positions that dewater mussel beds 
(Vannote and Minshall 1982, p. 4105; Gordon et al. 1992, pp. 296-297; 
Kanehl and Lyons 1992, pp. 26-27; Brim Box and Mossa 1999, p. 102).
    Interstitial spaces in the substrate provide essential habitat for 
juvenile mussels. When they are clogged, interstitial flow rates and 
spaces may become reduced (Brim Box and Mossa 1999, p. 100), thus 
reducing juvenile habitat availability. The rayed bean burrows deep 
into interstitial substrates, making it particularly susceptible to 
degradation of this habitat. Sediment may act as a vector for 
delivering contaminants, such as nutrients and pesticides, to streams. 
Juveniles can readily ingest contaminants adsorbed to silt particles 
during normal feeding activities. These factors may explain, in part, 
why so many mussel populations, including those of the rayed bean and 
snuffbox, appear to be experiencing recruitment failures.
    Agricultural activities produce the most significant amount of 
sediment that enters streams (Waters 1995, pp. 17-18). Neves et al. 
(1997, p. 65) stated that agriculture (including both sediment and 
chemical runoff) affects 72 percent of the impaired river miles in the 
country. Unrestricted access by livestock is a significant threat to 
many streams and their mussel populations (Fraley and Ahlstedt 2000, p. 
193). Soil compaction for intensive grazing may reduce infiltration 
rates and increase runoff, and trampling of riparian vegetation 
increases the probability of erosion (Armour et al. 1991, pp. 8-10; 
Trimble and Mendel 1995, pp. 238-239; Brim Box and Mossa 1999, p. 103).
    The majority of extant rayed bean and snuffbox populations are 
threatened by some form of agricultural runoff (e.g., nutrients, 
pesticides, and sediment). The Maumee River system, for example, has a 
drainage area that contains approximately 89 percent agricultural land 
(Sanders 2002, p. 10.1). The decline of rayed bean and snuffbox in this 
system may be largely attributed to stream habitat impacts resulting 
from intensive farming and associated runoff. The rayed bean and 
snuffbox once occurred in the Maumee River mainstem, as well as in up 
to nine of its tributaries. Currently, the snuffbox is extirpated from 
the Maumee River system and the rayed bean is only found in distinct 
but small reaches of the St. Joseph River, Fish Creek, Swan Creek, and 
Blanchard River. All of these remaining populations (which comprise 
about 20 percent of all remaining rayed bean populations rangewide) are 
currently threatened by ongoing agricultural activities. This scenario 
is echoed across the remaining extant range of the rayed bean and 
snuffbox.
    Other Activities Affecting Rayed Bean and Snuffbox Habitat--
Activities associated with urbanization can be detrimental to stream 
habitats (Couch and Hamilton 2002, p. 1) and were summarized by 
Feminella and Walsh (2005, pp. 585-587). Developmental activities may 
impact streams and their mussel fauna where adequate streamside buffers 
are not maintained and erosion of impacted land is allowed to enter 
streams (Brainwood et al. 2006, p. 511). Types of development may 
include highway construction, parking

[[Page 8657]]

lots, building construction, general infrastructure (e.g., utilities, 
sewer systems), and recreation facilities. Factors impacting rayed bean 
and snuffbox populations in urban and suburban areas include lawn care 
chemicals (Conners and Black 2004, pp. 366-367), sedimentation, toxic 
effluents, domestic sewage, road salts, and general runoff.
    Impervious surfaces are detrimental to mussel habitat by altering 
various hydrological factors, including: Increased volumes of flow, 
annual flow rates, peak flows and duration, and temperature; decreased 
base flow; and changes in sediment loadings (Galli 1991, p. 28; EPA 
1997, p. 4; DeWalle et al. 2000, p. 2655; Myers-Kinzie et al. 2002, p. 
822). These factors result in flooding, erosion, channel widening, 
altered streambeds, channel instability, riparian and instream habitat 
loss, and loss of fish populations (EPA 1997, p. 4). As little as 10 
percent of a watershed being impervious can cause channel instability 
and a host of other stream habitat effects (Booth 1991, p. 98; Booth 
and Reinelt 1993, p. 549). Impervious surfaces may reduce sediment 
input into streams but result in channel instability by accelerating 
stormwater runoff, which increases bank erosion and bed scouring (Brim 
Box and Mossa 1999, p. 103). Stream channels become highly unstable as 
they respond to increased flows by eroding a groove in the bottom of 
the channel (incising), which increases the force of the water against 
the channel (shear stress) and bed mobilization (Doyle et al. 2000, p. 
156). Hydrological variability influences the distribution of mussels 
in streams, with distinct communities associated with hydrologically 
flashy and hydrologically stable streams (Di Maio and Corkum 1995, p. 
669). High shear stress, peak flows, and substrate movement limit 
mussel communities, reduce abundance (particularly for juveniles), and 
increasingly dislodge mussels and move them downstream (Layzer and 
Madison 1995, p. 337; Myers-Kinzie et al. 2002, p. 822; Gangloff and 
Feminella 2007, p. 70). Recruitment is also significantly reduced in 
high discharge years (Howard and Cuffey 2006, p. 688). Most rayed bean 
and snuffbox streams have been impacted by general developmental 
activities and increased impervious surface levels (Butler 2002, p. 25; 
Butler 2007, p. 88).
    All rayed bean or snuffbox streams are crossed by bridges and 
roads. Effects from these structures were reviewed by Wheeler et al. 
(2005). Categories of impacts include primary effects (construction), 
secondary effects (post-construction), and indirect effects 
(development associated with highway presence) (Angermeier et al. 2004, 
pp. 21-24). Culverts act as barriers to fish passage (Wheeler et al. 
2005, p. 149), particularly by increasing flow velocity (Warren and 
Pardew 1998, p. 637). Stream channels become destabilized when 
culverted or improperly bridged by interrupting the transport of woody 
debris, substrate, and water (Wheeler et al. 2005, p. 152).
    Anthropogenic activities can lower water tables, making rayed bean, 
snuffbox, and other mussel populations susceptible to depressed flow 
levels. Water withdrawals for irrigation, municipal, and industrial 
water supplies are an increasing concern. United States water 
consumption doubled from 1960 to 2000 and is likely to increase further 
(Naiman and Turner 2000, p. 960). Therefore, we anticipate water 
withdrawals and potential stream dewatering to be a threat to rayed 
bean and snuffbox in the foreseeable future.
    Summary of Factor A: We have identified a number of threats to the 
habitat of the rayed bean and snuffbox which have operated in the past, 
are impacting the species now, and will continue to impact the species 
in the foreseeable future. On the basis of this analysis, we find that 
the present and threatened destruction, modification, or curtailment of 
the species' habitats are a threat to the rayed bean and snuffbox 
throughout all of their range. Based on our analysis of the best 
available data, we determine that the present or threatened 
destruction, modification, or curtailment of rayed bean or snuffbox 
habitat will not change in the foreseeable future. The decline of the 
freshwater mussels in the eastern United States is primarily the result 
the long-lasting effects of habitat alterations such as impoundments, 
channelization, chemical contaminants, mining, and sedimentation. 
Although efforts have been made to restore habitat in some areas, the 
long-term effects of large-scale and wide-ranging habitat modification, 
destruction, and curtailment will last far into the foreseeable future.

B. Overutilization for Commercial, Recreational, Scientific, or 
Educational Purposes

    The rayed bean and snuffbox are not commercially valuable species. 
Rare species like the rayed bean and snuffbox may increasingly be 
sought by lay and experienced collectors. Most stream reaches inhabited 
by these species are restricted, and the populations are generally 
small. Although scientific collecting is not thought to represent a 
significant threat, localized populations could become impacted and 
possibly extirpated by over-collecting, particularly if this activity 
is unregulated. Native Americans were known to harvest the rayed bean 
for food, but because of its size, utilization rates were very low 
(Bogan 1990, p. 134). Localized declines of snuffbox from use as bait 
by fishermen have been noted (Cumberland River; Wilson and Clark 1914, 
p. 45), although it is unlikely that exploitation activities have 
eliminated any snuffbox populations.
    On the basis of the best scientific and commercial data available, 
we find that overutilization for commercial, recreational, scientific, 
or educational purposes is currently not a threat to the rayed bean or 
snuffbox in any portion of their range or likely to become a 
significant threat in the foreseeable future.

C. Disease or Predation

    Little is known about diseases in freshwater mussels (Grizzle and 
Brunner 2007, p. 2). However, mussel die-offs have been documented in 
rayed bean and snuffbox streams (Neves 1986, p. 9), and some 
researchers believe that disease may be a factor contributing to the 
die-offs (Buchanan 1986, p. 53; Neves 1986, p. 11). Mussel parasites 
include water mites, trematodes, oligochaetes, leeches, copepods, 
bacteria, and protozoa (Grizzle and Brunner 2007, p. 2). Generally, 
parasites are not suspected of being a major limiting factor (Oesch 
1984, p. 16), but a study provides contrary evidence. Reproductive 
output and physiological condition were negatively correlated with mite 
and trematode abundance, respectively (Butler 2007, p. 88). Stressors 
that reduce fitness may make mussels more susceptible to parasites 
(Butler 2007, p. 90). Furthermore, nonnative mussels may carry diseases 
and parasites that are potentially devastating to native mussel fauna, 
including rayed bean and snuffbox (Strayer 1999b, p.88).
    The muskrat (Ondatra zibethicus) is cited as the most prevalent 
mussel predator (Kunz 1898, p. 328; Hanson et al. 1989, p. 15). Muskrat 
predation may limit the recovery potential of endangered mussels or 
contribute to local extirpations of previously stressed populations, 
according to Neves and Odom (1989, p. 940), but they consider it 
primarily a seasonal or localized threat. The snuffbox ranked fourth 
among 12 species in a St. Croix River muskrat midden (shell pile), 
being nearly four times more abundant than in quantitative surveys 
(Tyrrell and Hornbach 1998, p. 304). Mussel

[[Page 8658]]

numbers were too low to determine selectivity indices or statistics.
    Muskrats were not thought to be a threat to the rayed bean by West 
et al. (2000, pp. 255-256), due to their general selection of mussels 
larger than 1.4-1.6 in (3.6-4.1 cm) long (Convey et al. 1989, p. 656; 
Hanson et al. 1989, p. 24). Neves and Odom (1989, pp. 938-939) also 
noted that muskrats did not select for small mussels. Nevertheless, 
some muskrat predation on the rayed bean has recently been documented 
in Cassadaga Creek, New York, but is generally considered insignificant 
(Butler 2002, p. 26).
    Other mammals (raccoon (Procyon lotor), mink (Mustela vison), river 
otter (Lutra canadensis), striped skunk (Mephitis mephitis), hog (Sus 
scrofa), rat (Rattus spp.)), amphibians (hellbender (Cryptobranchus 
alleganiensis)), turtles, aquatic birds, and fishes (freshwater drum 
(Aplodinotus grunniens), redear sunfish (Lepomis microlophus)) feed on 
mussels (Kunz 1898, p. 328; Meek and Clark 1912, p. 6; Neck 1986, p. 
64; Tyrrell and Hornbach 1998, p. 301). Hydra, non-biting midge larvae, 
dragonfly larvae, crayfish, and especially flatworms are invertebrate 
predators on newly metamorphosed juveniles (Zimmerman and Neves 2003, 
p. 28; Klocker and Strayer 2004, p. 174). However, the overall threat 
posed by these predators on the rayed bean and snuffbox is not 
considered significant.
    Studies indicate that, in some localized areas, disease and 
predation may have negative impacts on mussel populations. However, 
based on our analysis of the best available scientific and commercial 
data available, we find that neither disease nor predation is a 
significant threat to the overall status of rayed bean or snuffbox, and 
we determine that these are not likely to become significant threats in 
the foreseeable future.

D. The Inadequacy of Existing Regulatory Mechanisms

    Most States with extant rayed bean and snuffbox populations 
prohibit collection of mussels without a State collecting permit. 
However, enforcement of this permit requirement is difficult. Until 
recently, it was legal to collect 50 mussels per day for use as fish 
bait in Pennsylvania. This practice was banned by a Pennsylvania Fish 
and Boat Commission final rulemaking, effective January 1, 2011 (Welte 
2011, pers. comm.; 40 Pennsylvania Bulletin 7233).
    Sources of nonpoint source pollution include timber clearcutting, 
clearing of riparian vegetation, urbanization, road construction, and 
other practices that allow bare earth to enter streams (The Nature 
Conservancy 2004, p. 13). Current Federal and State laws do not 
adequately protect rayed bean and snuffbox habitat from nonpoint source 
pollution, as the laws to prevent sediment entering waterways are 
poorly enforced. Best management practices for sediment and erosion 
control are often recommended or required by local ordinances for 
construction projects; however, compliance, monitoring, and enforcement 
of these recommendations are often poorly implemented. Furthermore, 
there are currently no requirements within the scope of Federal 
environmental laws to specifically consider the rayed bean or snuffbox 
during Federal activities, or to ensure that Federal projects will not 
jeopardize their continued existence.
    Point source discharges within the range of the rayed bean and 
snuffbox have been reduced since the inception of the Clean Water Act 
(33 U.S.C. 1251 et seq.), but this may not provide adequate protection 
for filter-feeding organisms that can be impacted by extremely low 
levels of contaminants (see Chemical Contaminants discussion under 
Factor A). There is no specific information on the sensitivity of the 
rayed bean and snuffbox to common industrial and municipal pollutants 
and very little information on other freshwater mussels. Therefore, it 
appears that a lack of adequate research and data prevents existing 
regulations, such as the Clean Water Act (administered by the EPA and 
the U.S. Army Corps of Engineers), from being fully used or effective.
    Despite these existing regulatory mechanisms, the rayed bean and 
snuffbox continue to decline due to the effects of habitat destruction, 
poor water quality, contaminants, and other factors. We find that these 
regulatory measures have been insufficient to significantly reduce or 
remove the threats to the rayed bean and snuffbox and, therefore, that 
the inadequacy of existing regulatory mechanisms is a threat to these 
species throughout all of their range.
    Based on our analysis of the best available scientific and 
commercial data, we do not find that the aforementioned regulations, 
which currently do not offer adequate protection to the rayed bean and 
snuffbox, will be improved in the foreseeable future.

E. Other Natural or Manmade Factors Affecting Their Continued Existence

    Other factors have played a role in the decline of rayed bean and 
snuffbox populations. Reduced numbers of host fish have an indirect 
impact by contributing to reduced recruitment (Watters 1996, p. 83; 
Khym and Layzer 2000, p. 183). Factors associated with climate change 
likely to affect regional mussel populations include changes in stream 
temperature regimes and precipitation levels that may indirectly result 
in reduced habitat and declines in host fish stocks (Hastie et al. 
2003, p. 44). Remedial (such as flood control structures) and 
preventative (for example, more renewable energy from hydroelectric 
facilities to reduce greenhouse gas emissions) measures to address 
climate change issues (Hastie et al. 2003, p. 45) may impact rayed bean 
and snuffbox populations in the future.
    Population Fragmentation and Isolation--The majority of the 
remaining populations of the rayed bean and snuffbox are generally 
small and geographically isolated. The patchy distributional pattern of 
populations in short river reaches makes them much more susceptible to 
extirpation from single catastrophic events, such as toxic chemical 
spills (Watters and Dunn 1993-94, p. 257). Furthermore, this level of 
isolation makes natural repopulation of any extirpated population 
unlikely without human intervention. Population isolation prohibits the 
natural interchange of genetic material between populations, and small 
population size reduces the reservoir of genetic diversity within 
populations, which can lead to inbreeding depression (Avise and 
Hambrick 1996, p. 461).
    The Scioto River system provides a good example of the impacts of 
population fragmentation and isolation. Historically, the rayed bean 
and snuffbox were widespread and locally abundant in the mainstem and 
numerous tributaries. The Scioto River became highly contaminated over 
a century ago (Trautman 1981, p. 33; Yoder et al. 2005, p. 410), and 
these species eventually died out in the mainstem and most tributaries. 
The population segments that persist have become increasingly isolated 
due to impoundments and other factors; all are very small, highly 
fragmented, and appear to be on a trend towards extirpation.
    Many rayed bean and snuffbox populations are potentially below the 
effective population size (EPS) required to maintain genetic 
heterogeneity and population viability (Soul[eacute] 1980, p. 162). The 
EPS is the number of individuals in a population who contribute 
offspring to the next generation. Isolated populations eventually die 
out when population size drops below the EPS or below the

[[Page 8659]]

number of individuals needed to sustain the population. Recruitment 
reduction or failure is a potential problem for many small rayed bean 
and snuffbox populations rangewide, a condition likely exacerbated by 
their reduced range and increasingly isolated populations. Evidence of 
recruitment has not been documented in many populations, indicating 
that recruitment reduction or outright failure is possible. Many 
populations of both species may be experiencing the bottleneck effect 
of not attaining EPS. This is supported by research by Zanatta and 
Murphy (2008, pp. 378-381) that suggests strong genetic isolation among 
snuffbox populations. Small, isolated, below-EPS-threshold populations 
of short-lived species (most host fishes) theoretically die out within 
a decade or so, while below-threshold populations of long-lived species 
(like the rayed bean and snuffbox) might take decades to die out, even 
given years of total recruitment failure.
    We find that fragmentation and isolation of small, remaining 
populations of the rayed bean and snuffbox are current and ongoing 
threats to both species throughout all of their range that will 
continue into the foreseeable future.
    Exotic Species--Various exotic or nonnative species of aquatic 
organisms are firmly established in the range of the rayed bean and 
snuffbox. The exotic species that poses the most significant threat to 
the rayed bean and snuffbox is the zebra mussel (Dreissena polymorpha). 
The invasion of the zebra mussel poses a threat to the mussel fauna in 
many regions, and species extinctions are expected as a result of its 
continued spread in the eastern United States (Ricciardi et al. 1998, 
p. 616). Strayer (1999b, pp. 77-80) reviewed in detail the mechanisms 
by which zebra mussels impact native mussels. The primary means of 
impact is direct fouling of the shells of live native mussels. Zebra 
mussels attach in large numbers to the shells of live native mussels 
and are implicated in the loss of entire native mussel beds. Fouling 
impacts include impeding locomotion (both laterally and vertically), 
interfering with normal valve movements, deforming valve margins, and 
locally depleting food resources and increasing waste products. Heavy 
infestations of zebra mussels on native mussels may overly stress the 
animals by reducing their energy stores. Zebra mussels may also reduce 
food concentrations to levels too low to support native mussel 
reproduction, or even survival, in extreme cases.
    Another way zebra mussels may impact native mussels is by filtering 
native mussel sperm and possibly glochidia from the water column, thus 
reducing reproductive potential. Habitat for native mussels may also be 
degraded by large deposits of zebra mussel pseudofeces (undigested 
waste material passed out of the incurrent siphon) (Vaughan 1997, p. 
11).
    Zebra mussels are thoroughly established in the Great Lakes 
drainages and much of the Ohio River system, overlapping much of the 
current range of the rayed bean and snuffbox. Zebra mussels have 
eliminated populations of the rayed bean in Lakes Erie and Tippecanoe 
and the Detroit River. The greatest current potential for zebra mussels 
to impact the rayed bean and snuffbox are in the Lake St. Clair 
drainages, Allegheny River, Tippecanoe River, French Creek, and Lake 
Maxinkuckee. In addition, there is long-term potential for zebra mussel 
invasions into other systems that currently harbor rayed bean and 
snuffbox populations. Significant, but highly fluctuating, zebra mussel 
populations remain largely restricted to navigational waterways, 
although smaller streams have also had their native mussel fauna 
virtually eliminated by zebra mussels (Martel et al. 2001, p. 2188). 
However, zebra mussels are not always a serious threat to rayed bean 
and snuffbox (Tippecanoe River, Fisher 2005, pers. comm.; Clinton 
River, Butler 2007, p. 94; French Creek, Butler 2007, p. 94). At least 
two of the stronghold snuffbox populations (Wolf River and French 
Creek) presently have low numbers of zebra mussels.
    The Asian clam (Corbicula fluminea) has spread throughout the range 
of the rayed bean and snuffbox since its introduction in the mid-1900s. 
Asian clams compete with native mussels, especially juveniles, for 
food, nutrients, and space (Neves and Widlak 1987, p. 6; Leff et al. 
1990, p. 415) and may ingest sperm, glochidia, and newly metamorphosed 
juveniles of native mussels (Strayer 1999b, p. 82; Yeager et al. 2001, 
p. 257). Dense Asian clam populations actively disturb sediments that 
may reduce habitat for juvenile mussels (Strayer 1999b, p. 82).
    Asian clam densities vary widely in the absence of native mussels 
or in patches with sparse mussel concentrations, but clam density is 
never high in dense mussel beds, indicating that the clam is unable to 
successfully invade small-scale habitat patches with high unionid 
biomass (Vaughn and Spooner 2006, p. 335). The invading clam therefore 
appears to preferentially invade sites where mussels are already in 
decline (Strayer 1999b, p. 82; Vaughn and Spooner 2006, p. 332) and 
does not appear be a causative factor in the decline of mussels in 
dense beds. However, an Asian clam population that thrives in 
previously stressed, sparse mussel populations can exacerbate unionid 
imperilment through competition and impeding mussel population 
expansion (Vaughn and Spooner 2006, p. 335).
    The round goby (Neogobius melanostomus) is another exotic fish 
species released into the Great Lakes that is well established and 
likely to spread through the Mississippi River system (Strayer 1999b, 
pp. 87-88). This species is an aggressive competitor of similar sized 
benthic fish (sculpins, darters), as well as a voracious carnivore 
despite its size (less than 10 in (25.4 cm) in length) that preys on a 
variety of foods, including small mussels and fishes that could serve 
as glochidial hosts (Strayer 1999b, p. 88; Janssen and Jude 2001, p. 
325). Round gobies may therefore have indirect effects on the rayed 
bean and snuffbox through negative impacts to their host fishes.
    The black carp (Mylopharyngodon piceus) is native to eastern Asia 
and a potential threat to the rayed bean and snuffbox (Strayer 1999b, 
p. 89). Nico et al. (2005) prepared a risk assessment of this species 
and summarized all known aspects of its ecology, life history, and 
intentional introduction (since the 1970s) into North America. A 
molluscivore, the black carp has been known to feed on unionids 
(bivalve mussels) and is proposed for widespread use by aquaculturists 
to control snails, the intermediate host of a trematode (flatworm) 
parasite infesting catfish in culture ponds. They are the largest of 
the Asian carp species, reaching 5 feet (1.5 meters) in length and 
achieving a weight in excess of 150 pounds (68 kilograms (kg)) (Nico et 
al. 2005, p. 25). Foraging rates for a 4-year-old fish average 3 or 4 
pounds (1.4-1.8 kg) a day, indicating that a single individual could 
consume 10 tons (9,072 kg) of native mollusks over its lifetime (MICRA 
2005, p. 1). Several black carp escaped from an aquaculture facility in 
Missouri during a flood in 1994, and a fish was caught a few years 
later in southern Illinois. The escape of nonsterile black carp is 
considered imminent by conservation biologists (Butler 2007, pp. 95-
96). The black carp was officially added to the Federal list of 
injurious wildlife species on October 18, 2007 (72 FR 59019).
    Another exotic species that has the potential to impact the rayed 
bean and snuffbox is Didymosphenia geminate, a diatom commonly known as 
``didymo''

[[Page 8660]]

or ``rock snot.'' This species, native to portions of North America, 
has recently expanded its range, and has begun occurring in large 
nuisance blooms that can dominate stream surfaces by covering 100 
percent of the substrate (USFWS 2010, pp. 17-18). Such dramatic 
alterations to streambed surfaces alone has the potential to directly 
affect embedded mussels and indirectly affect the ability of mussels to 
complete their life cycles by modifying the habitat of their host fish. 
Didymo has been found in the Elk River in West Virginia, a stream that 
currently supports both a snuffbox and rayed bean population. The 
extent of the didymo range in the Elk River currently appears to be 
upstream of the rayed bean and snuffbox occurrences. However, the 
potential for didymo to spread downstream poses a threat to both mussel 
species.
    Another exotic species that has recently been found within the 
range of the snuffbox is golden algae (Prymnesium parvum) (USEPA 2009, 
p. 2). Golden algae is a saltwater algae with blooms associated with 
increased salinity. In 2009, an aquatic life kill in Dunkard Creek in 
Pennsylvania and West Virginia was attributed to bloom of this algae in 
response to high levels of total dissolved solids, possibly stemming 
from briny discharges from an underground coal mine (USEPA 2009, pp. 1-
3). The toxic event is thought to have eliminated the snuffbox from 
Dunkard Creek (Clayton 2009, pers. comm.; USEPA 2009, p. 5).
    Additional exotic species will invariably become established in the 
United States in the foreseeable future (Strayer 1999b, pp. 88-89). 
These include Limnoperna fortunei, a biofouling mussel (an animal that 
undesirably accumulates on wetted surfaces), from southeast Asia that 
has already spread to Japan and South America, and ``probably will have 
strong effects'' on native mussels (Strayer 1999b, p. 89). Furthermore, 
exotic species could carry diseases and parasites that may be 
devastating to the native biota. Because of our ignorance of mollusk 
diseases and parasites, ``it is imprudent to conclude that alien 
diseases and parasites are unimportant'' (Strayer 1999b, p. 88). Exotic 
species, such as those described above, are an ongoing threat to the 
rayed bean and snuffbox--a threat that is likely to increase as these 
exotic species expand their occupancy within the range of the rayed 
bean and snuffbox.
    Summary of Factor E: The majority of the remaining populations of 
the rayed bean and snuffbox are generally small and geographically 
isolated, making natural repopulation of extirpated populations 
unlikely without human intervention. Furthermore, many of the remaining 
populations are likely below the EPS, making future extirpations likely 
within the foreseeable future. In addition, various exotic species are 
well established with the range of the rayed bean and snuffbox. Exotic 
species, including the zebra mussel, Asian clam, round goby, and black 
carp, threaten the rayed bean and snuffbox, or their host fish, or 
both, through mechanisms such as habitat modification, competition, and 
predation.

Summary of Threats

    The decline of the rayed bean and snuffbox (described by Butler 
2002, 2007) is primarily the result of habitat loss and degradation 
(Neves 1991, p. 252). These losses have been well documented since the 
mid-19th century (Higgins 1858, p. 551). Chief among the causes of 
decline are impoundments, channelization, chemical contaminants, 
mining, and sedimentation (Neves 1991, pp. 260-261; 1993, pp. 4-5; 
Williams et al. 1993, p. 7; Neves et al. 1997, pp. 60-72; Watters 2000, 
p. 269). These stressors have had profound impacts on rayed bean and 
snuffbox populations and their habitat.
    Current Federal and State laws do not adequately protect rayed bean 
and snuffbox from non-point source pollution. The lack of information 
on the sensitivity of the rayed bean and snuffbox to point source 
discharges of common industrial and municipal pollutants prevents 
existing regulations, such as the Clean Water Act, from being fully 
used or effective. Despite the existing regulatory mechanisms, the 
rayed bean and snuffbox continue to decline due to the effects of 
habitat destruction, poor water quality, contaminants, and other 
factors.
    The majority of the remaining populations of the rayed bean and 
snuffbox are generally small and geographically isolated (Butler 2002, 
p. 26; 2007, p. 92). The patchy distributional pattern of populations 
in short river reaches makes those populations much more susceptible to 
extirpation from single catastrophic events, such as toxic chemical 
spills (Watters and Dunn 1993-94, p. 257). Furthermore, this level of 
isolation makes natural repopulation of any extirpated population 
virtually impossible without human intervention. Various nonnative 
species of aquatic organisms are firmly established in the range of the 
rayed bean and snuffbox; however, the exotic species that poses the 
most significant threat to the rayed bean and snuffbox is the zebra 
mussel (Dreissena polymorpha) (Butler 2002, p. 27; 2007, p. 93).

Determination

    Section 3 of the Act defines an endangered species as any species 
that is ``in danger of extinction throughout all or a significant 
portion of its range'' and a threatened species as any species that 
``is likely to become an endangered species within the foreseeable 
future throughout all or a significant portion of its range.'' We find 
that the rayed bean and snuffbox are presently in danger of extinction 
throughout their entire range, based on the immediacy, severity, and 
extent of the threats described above. Although there are ongoing 
attempts to alleviate some threats, there appear to be no populations 
without current significant threats and many threats are without 
obvious or readily available solutions. On the basis of the best 
available scientific and commercial data, the rayed bean and snuffbox 
meet the definition of endangered species under the Act, rather than 
threatened species, because the significant threats are occurring now, 
making these species in danger of extinction at the present time. 
Therefore, endangered status is appropriate for the rayed bean and 
snuffbox in accordance with sections 3(6) and 4(a)(1) of the Act.
    Under the Act and our implementing regulations, a species may 
warrant listing if it is endangered or threatened throughout all or a 
significant portion of its range. Threats to the rayed bean and 
snuffbox occur throughout their ranges. Therefore, we assessed the 
status of the species throughout their entire ranges. The threats to 
the survival of the species occur throughout the species' ranges and 
are not restricted to any particular significant portion of those 
ranges. Accordingly, our assessment and determination applies to the 
species throughout their entire ranges.

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 results in public awareness and 
conservation by Federal, State, Tribal, and local agencies, private 
organizations, and individuals. The Act encourages cooperation with the 
States and requires that recovery actions be carried out for all listed 
species. The protection required by Federal agencies and the 
prohibitions against certain activities are discussed, in part, below.

[[Page 8661]]

    The primary purpose of the Act is the conservation of endangered 
and threatened species and the ecosystems upon which they depend. The 
ultimate goal of such conservation efforts is the recovery of these 
listed species, so that they no longer need the protective measures of 
the Act. Subsection 4(f) of the Act requires the Service to develop and 
implement recovery plans for the conservation of endangered and 
threatened species. The recovery planning process involves the 
identification of actions that are necessary to halt or reverse the 
species' decline by addressing the threats to its survival and 
recovery. The goal of this process is to restore listed species to a 
point where they are secure, self-sustaining, and functioning 
components of their ecosystems.
    Recovery planning includes the development of a recovery outline 
shortly after a species is listed, preparation of a draft and final 
recovery plan, and revisions to the plan as significant new information 
becomes available. The recovery outline guides the immediate 
implementation of urgent recovery actions and describes the process to 
be used to develop a recovery plan. The recovery plan identifies site-
specific management actions that will achieve recovery of the species, 
measurable criteria that guide when a species may be downlisted or 
delisted, and methods for monitoring recovery progress. Recovery plans 
also establish a framework for agencies to coordinate their recovery 
efforts and provide estimates of the cost of implementing recovery 
tasks. Recovery teams (comprised of species experts, Federal and State 
agencies, non-government organizations, and stakeholders) are often 
established to develop recovery plans. When completed, the recovery 
outline, draft recovery plan, and the final recovery plan will be 
available on our Web site (http://www.fws.gov/endangered), or from our 
Columbus Ecological Services Field Office (see FOR FURTHER INFORMATION 
CONTACT).
    Implementation of recovery actions generally requires the 
participation of a broad range of partners, including other Federal 
agencies, States, Tribal, non-governmental organizations, businesses, 
and private landowners. Examples of recovery actions include habitat 
restoration (e.g., restoration of native vegetation), research, captive 
propagation and reintroduction, and outreach and education. The 
recovery of many listed species cannot be accomplished solely on 
Federal lands because their range may occur primarily or solely on non-
Federal lands. To achieve recovery of these species requires 
cooperative conservation efforts on private, State, and Tribal lands.
    Once a species is listed, funding for recovery actions will be 
available from a variety of sources, including Federal budgets, State 
programs, and cost share grants for non-Federal landowners, the 
academic community, and nongovernmental organizations. Additionally, 
under section 6 of the Act, we would be able to grant funds to the 
States of Illinois, Indiana, Kentucky, Michigan, New York, Ohio, 
Pennsylvania, Tennessee, Virginia, and West Virginia for management 
actions promoting the conservation of the rayed bean and to the States 
of Alabama, Arkansas, Illinois, Indiana, Iowa, Kansas, Kentucky, 
Michigan, Minnesota, Mississippi, Missouri, New York, Ohio, 
Pennsylvania, Tennessee, Virginia, West Virginia, and Wisconsin for the 
conservation of the snuffbox. Information on our grant programs that 
are available to aid species recovery can be found at: http://www.fws.gov/grants.
    Please let us know if you are interested in participating in 
recovery efforts for these species. Additionally, we invite you to 
submit any new information on these species whenever it becomes 
available and any information you may have for recovery planning 
purposes. Please send it to the street address provided in the 
ADDRESSES section.
    Section 7(a) of the Act 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)(4) requires Federal agencies to confer informally with us 
on any action that is likely to jeopardize the continued existence of a 
proposed species or result in destruction or adverse modification of 
proposed critical habitat. If a species is listed subsequently, section 
7(a)(2) 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 such 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 us.
    Federal agency actions that may require conference or consultation 
as described in the preceding paragraph include the issuance of permits 
for reservoir construction, stream alterations, wastewater facility 
development, water withdrawal projects, pesticide registration, 
agricultural assistance programs, mining, road and bridge construction, 
and Federal loan programs. Activities will trigger consultation under 
section 7 of the Act if they may affect the rayed bean or snuffbox, or 
both species, addressed in this final rule.

Jeopardy Standard

    Prior to and following listing and designation of critical habitat, 
if prudent and determinable, the Service applies an analytical 
framework for jeopardy analyses that relies heavily on the importance 
of core area populations to the survival and recovery of the species. 
The section 7(a)(2) analysis is focused not only on these populations 
but also on the habitat conditions necessary to support them.
    The jeopardy analysis usually expresses the survival and recovery 
needs of the species in a qualitative fashion without making 
distinctions between what is necessary for survival and what is 
necessary for recovery. Generally, if a proposed Federal action is 
incompatible with the viability of the affected core area 
populations(s), inclusive of associated habitat conditions, a jeopardy 
finding is considered to be warranted, because of the relationship of 
each core area population to the survival and recovery of the species 
as a whole.

Section 9 Take

    The Act and implementing regulations set forth a series of general 
prohibitions and exceptions that apply to all endangered and threatened 
wildlife. With this final rule listing the rayed bean and snuffbox as 
endangered, these prohibitions are applicable to the rayed bean and 
snuffbox. The prohibitions of section 9(a)(2) of the Act, codified at 
50 CFR 17.21 for endangered wildlife, 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, 
deliver, receive, carry, transport, or ship in interstate or foreign 
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 such 
wildlife that has been taken illegally. Further, it is illegal for any 
person to attempt to commit, to solicit another person to commit, or to 
cause to be committed, any of these acts. Certain exceptions apply to 
our agents and State conservation agencies.

[[Page 8662]]

    We may issue permits to carry out otherwise prohibited activities 
involving endangered wildlife under certain circumstances. We codified 
the regulations governing permits for endangered species at 50 CFR 
17.22. Such permits are available for scientific purposes, to enhance 
the propagation or survival of the species, or for incidental take in 
the course of otherwise lawful activities.
    It is our policy, published in the Federal Register on July 1, 1994 
(59 FR 34272), to identify, to the maximum extent practicable at the 
time a species is listed, those activities that would or would not 
constitute a violation of section 9 of the Act and associated 
regulations at 50 CFR 17.21. The intent of this policy is to increase 
public awareness of the effect of this final listing on proposed and 
ongoing activities within a species' range. We determine, based on the 
best available data, 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) Activities authorized, funded, or carried out by Federal 
agencies (e.g., bridge and highway construction, pipeline construction, 
hydropower licensing), when such activities are conducted in accordance 
with the consultation and planning requirements for listed species 
under section 7 of the Act.
    (2) Any action carried out for scientific research or to enhance 
the propagation or survival of the rayed bean or snuffbox that is 
conducted in accordance with the conditions of a 50 CFR 17.22 permit.
    (3) Any incidental take of rayed bean or snuffbox resulting from an 
otherwise lawful activity conducted in accordance with the conditions 
of an incidental take permit issued under 50 CFR 17.22. Non-Federal 
applicants may design a habitat conservation plan (HCP) for the species 
and apply for an incidental take permit. HCPs may be developed for 
listed species and are designed to minimize and mitigate impacts to the 
species to the greatest extent practicable.
    We determine that the following activities would be likely to 
result in a violation of section 9 of the Act; however, possible 
violations are not limited to these actions alone:
    (1) Unauthorized killing, collecting, handling, or harassing of 
individual rayed bean or snuffbox, or both species, at any life stage.
    (2) Sale or offer for sale of rayed bean or snuffbox in addition to 
delivering, receiving, carrying, transporting, or shipping in 
interstate or foreign commerce any rayed bean or snuffbox.
    (3) Unauthorized destruction or alteration of the species' habitat 
(instream dredging, channelization, impoundment, streambank clearing, 
discharge of fill material) that actually kills or injures individual 
rayed bean or snuffbox by significantly impairing their essential 
behavioral patterns, including breeding, feeding, or sheltering.
    (4) Violation of any discharge or water withdrawal permit within 
these species' occupied ranges that results in the death or injury of 
individual rayed bean or snuffbox by significantly impairing their 
essential behavioral patterns, including breeding, feeding, or 
sheltering.
    (5) Discharge or dumping of toxic chemicals or other pollutants 
into waters supporting the species that actually kills or injures 
individual rayed bean or snuffbox by significantly impairing their 
essential behavioral patterns, including breeding, feeding, or 
sheltering.
    We will review other activities not identified above on a case-by-
case basis to determine whether they may be likely to result in a 
violation of section 9 of the Act. We do not consider these lists to be 
exhaustive and provide them as information to the public.
    You should direct questions regarding whether specific activities 
may constitute a future violation of section 9 of the Act to the Field 
Supervisor of the Service's Columbus Ecological Services Field Office 
(see ADDRESSES section). 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, 5600 American Blvd. West, Suite 990, Bloomington, MN 55437 
(Phone 612-713-5350; Fax 612-713-5292).

Critical Habitat

Background

    Critical habitat is defined in section 3 of the Act as:
    (i) The specific areas within the geographical area occupied by a 
species, at the time it is listed in accordance with the Act, on which 
are found those physical or biological features
    (I) essential to the conservation of the species and
    (II) that may require special management considerations or 
protection; and
    (ii) Specific areas outside the geographical area occupied by a 
species at the time it is listed, upon a determination that such areas 
are essential for the conservation of the species.
    ``Conservation'' is defined in section 3 of the Act as meaning the 
use of all methods and procedures needed to bring the species to the 
point at which listing under the Act is 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) requires consultation on Federal actions that 
may affect critical habitat. The designation of critical habitat does 
not affect land ownership or establish a refuge, wilderness, reserve, 
preserve, or other conservation area. Such designation does not allow 
the government or public to access private lands. Such designation does 
not require implementation of restoration, recovery, or enhancement 
measures by non-Federal landowners. Where a landowner seeks or requests 
Federal agency funding or authorization for an action that may affect a 
listed species or critical habitat, the consultation requirements of 
section 7(a)(2) of the Act would apply, but 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.
    For inclusion in a critical habitat designation, the habitat within 
the geographical area occupied by the species at the time it was listed 
must contain the physical and biological features essential to the 
conservation of the species, and be included only if those features may 
require special management considerations or protection. Critical 
habitat designations identify, to the extent known using the best 
scientific and commercial data available, habitat areas that provide 
essential life cycle needs of the species (areas on which are found the 
physical and biological features (PBFs) laid out in the appropriate 
quantity and spatial arrangement for the conservation of the species). 
Under the Act and regulations at 50 CFR 424.12, we can designate 
critical habitat in areas outside the geographical area occupied by the 
species at the time it is listed only when we determine that those 
areas are essential for the conservation of the species and that 
designation limited to those areas occupied at the time of listing 
would be inadequate to ensure the conservation of the species.
    Section 4 of the Act requires that we designate critical habitat on 
the basis of the best scientific and commercial data

[[Page 8663]]

available. Further, our Policy on Information Standards Under the 
Endangered Species Act (published in the Federal Register on July 1, 
1994 (59 FR 34271)), the Information Quality Act (section 515 of the 
Treasury and General Government Appropriations Act for Fiscal Year 2001 
(Pub. L. 106-554; H.R. 5658)), and our associated Information Quality 
Guidelines, provide criteria, establish procedures, and provide 
guidance to ensure that our decisions are based on the best scientific 
data available. They require our biologists, to the extent consistent 
with the Act and with the use of the best scientific data available, to 
use primary and original sources of information as the basis for 
recommendations to designate critical habitat.
    When we are determining which areas should be designated as 
critical habitat, our primary source of information is generally the 
information developed during the listing process for the species. 
Additional information sources may include the recovery plan for the 
species, articles in peer-reviewed journals, conservation plans 
developed by States and counties, scientific status surveys and 
studies, biological assessments, or other unpublished materials and 
expert opinion or personal knowledge.
    Habitat is often dynamic, and species may move from one area to 
another over time. Furthermore, we recognize that critical habitat 
designated at a particular point in time may not include all of the 
habitat areas that we may later determine are necessary for the 
recovery of the species. For these reasons, a critical habitat 
designation does not signal that habitat outside the designated area is 
unimportant or may not be required for recovery of the species.
    Areas that are important to the conservation of the species, but 
are outside the critical habitat designation, will continue to be 
subject to conservation actions we implement under section 7(a)(1) of 
the Act. Areas that support populations are also subject to the 
regulatory protections afforded by the section 7(a)(2) jeopardy 
standard, as determined on the basis of the best available scientific 
information at the time of the agency action. Federally funded or 
permitted projects affecting listed species outside their designated 
critical habitat areas may still result in jeopardy findings in some 
cases. Similarly, critical habitat designations made on the basis of 
the best available information at the time of designation will not 
control the direction and substance of future recovery plans, habitat 
conservation plans (HCPs), or other species conservation planning 
efforts if new information available at the time of these planning 
efforts calls for a different outcome.

Prudency Determination

    Section 4(a)(3) of the Act, as amended, and implementing 
regulations (50 CFR 424.12), require that, to the maximum extent 
prudent and determinable, we designate critical habitat at the time we 
determine that a species is endangered or threatened. Our regulations 
(50 CFR 424.12(a)(1)) state that the designation of critical habitat is 
not prudent when one or both of the following situations exist: (1) The 
species is threatened by taking or other human activity, and 
identification of critical habitat can be expected to increase the 
degree of threat to the species, or (2) such designation of critical 
habitat would not be beneficial to the species.
    There is currently no imminent threat of take attributed to 
collection or vandalism under Factor B (overutilization for commercial, 
recreational, scientific, or educational purposes) for the rayed bean 
or snuffbox, and identification of critical habitat is not expected to 
initiate such a threat. In the absence of finding that the designation 
of critical habitat would increase threats to a species, if there are 
any benefits to a critical habitat designation, then a prudent finding 
is warranted. The potential benefits include: (1) Triggering 
consultation under section 7(a)(2) of the Act in new areas for actions 
in which there may be a Federal nexus where it would not otherwise 
occur because the species may not be present; (2) focusing conservation 
activities on the most essential habitat features and areas; (3) 
increasing awareness of important habitat areas among State or county 
governments, or private entities; and (4) preventing inadvertent harm 
to the species.
    Critical habitat designation includes the identification of the 
physical and biological features of the habitat essential to the 
conservation of each species that may require special management and 
protection. As such, these designations will provide useful information 
to individuals, local and State governments, and other entities engaged 
in activities or long-range planning that may affect areas essential to 
the conservation of the species. Conservation of the rayed bean and 
snuffbox and essential features of their habitats will require habitat 
management, protection, and restoration, which will be facilitated by 
disseminating information on the locations and the key physical and 
biological features of those habitats. In the case of the rayed bean 
and snuffbox, these aspects of critical habitat designation would 
potentially benefit the conservation of the species. Therefore, as we 
have determined that the designation of critical habitat will not 
likely increase the degree of threat to these species and may provide 
some measure of benefit, we find that designation of critical habitat 
is prudent for the rayed bean and snuffbox. However, a designation of 
critical habitat would be limited to lands within the jurisdiction of 
the United States and not include stream reaches in Canada (50 CFR 
424.12(h)).

Critical Habitat Determinability

    As stated above, section 4(a)(3) of the Act requires the 
designation of critical habitat concurrently with the species' listing 
``to the maximum extent prudent and determinable.'' Our regulations at 
50 CFR 424.12(a)(2) state that critical habitat is not determinable 
when one or both of the following situations exist:
    (i) Information sufficient to perform required analyses of the 
impacts of the designation is lacking, or
    (ii) The biological needs of the species are not sufficiently well 
known to permit identification of an area as critical habitat.
    When critical habitat is not determinable, the Act provides for an 
additional year to publish a critical habitat designation (16 U.S.C. 
1533(b)(6)(C)(ii)).
    In accordance with sections 3(5)(A)(i) and 4(b)(1)(A) of the Act 
and regulations at 50 CFR 424.12, in determining which areas to propose 
as critical habitat, we must consider those physical and biological 
features essential to the conservation of the species. 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.
    We are currently unable to identify the physical and biological 
features essential for the conservation of the rayed bean and snuffbox 
because information on those features for these species is not known at 
this time. The apparent poor viability of the species'

[[Page 8664]]

occurrences observed in recent years indicates that current conditions 
are not sufficient to meet the basic biological requirements of these 
species in many rivers. Because the rayed bean and snuffbox have not 
been observed for decades in many of their historical locations, and 
much of the habitat in which they still persist has been drastically 
altered, the optimal conditions that would provide the biological or 
ecological requisites of these species are not known. Although we can 
surmise that habitat degradation from a variety of factors has 
contributed to the decline of these species, we do not know 
specifically what essential physical or biological features of that 
habitat are currently lacking for the rayed bean and snuffbox.
    Key features of the basic life history, ecology, reproductive 
biology, and habitat requirements of most mussels, including the rayed 
bean and snuffbox, are unknown. Species-specific ecological 
requirements have not been determined (for example, minimum water flow 
and effects of particular pollutants). Population dynamics, such as 
species' interactions and community structure, population trends, and 
population size and age class structure necessary to maintain long-term 
viability, have not been determined for these species. Of particular 
concern to both species is that many of the remaining rayed bean and 
snuffbox populations consist of very low densities, a fact that limits 
our ability to investigate their population dynamics. Basics of 
reproductive biology for these species are unknown, such as age and 
size at earliest maturity, reproductive longevity, and the level of 
recruitment needed for species' survival and long-term viability. As we 
are unable to identify many physical and biological features essential 
to the conservation of the rayed bean and snuffbox, we are unable to 
identify areas that contain these features. Therefore, although we have 
determined that the designation of critical habitat is prudent for the 
rayed bean and snuffbox, because the biological and physical 
requirements of these species are not sufficiently known, we find that 
critical habitat for the rayed bean and snuffbox is not determinable at 
this time.

Required Determinations

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

    This final rule does not contain any new collections of information 
that require approval by the Office of Management and Budget (OMB) 
under the Paperwork Reduction Act. This rule will not impose new 
recordkeeping or reporting requirements on State or local governments, 
individuals, businesses, or organizations. We may not conduct or 
sponsor, and you are not required to respond to, a collection of 
information unless it displays a currently valid OMB control number.

National Environmental Policy Act (42 U.S.C. 4321 et seq.)

    We have determined that we do not need to prepare an environmental 
assessment, as defined under the authority of the National 
Environmental Policy Act of 1969, 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).

References Cited

    A complete list of all references cited in this final rule is 
available on the Internet at http://www.regulations.gov or upon request 
from the Field Supervisor, Columbus Ecological Services Field Office 
(see ADDRESSES section).

Author

    The primary author of this final rule is a staff member of the 
Columbus Ecological Services Field Office (see ADDRESSES section).

List of Subjects in 50 CFR Part 17

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

Regulation Promulgation

    Accordingly, we hereby amend part 17, subchapter B of chapter I, 
title 50 of the Code of Federal Regulations, as follows:

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) by adding new entries for ``Mussel, rayed 
bean'' and ``Mussel, snuffbox'' in alphabetical order under CLAMS to 
the List of Endangered and Threatened Wildlife as follows:


Sec.  17.11  Endangered and threatened wildlife.

* * * * *
    (h) * * *

--------------------------------------------------------------------------------------------------------------------------------------------------------
                            Species                                                       Vertebrate population
---------------------------------------------------------------      Historic range        where endangered or     Status     When    Critical   Special
             Common name                   Scientific name                                      threatened                   listed    habitat    rules
--------------------------------------------------------------------------------------------------------------------------------------------------------
 
                                                                      * * * * * * *
                Clams
 
                                                                      * * * * * * *
Mussel, rayed bean...................  Villosa fabalis........  U.S.A. (IL, IN, KY, MI,  NA.....................        E       798        NA        NA
                                                                 NY, OH, PA, TN, VA,
                                                                 WV); Canada (ON).
 
                                                                      * * * * * * *
Mussel, snuffbox.....................  Epioblasma triquetra...  U.S.A. (AL, AR, IL, IN,  NA.....................        E       798        NA        NA
                                                                 IA, KS, KY, MI, MN,
                                                                 MS, MO, NY, OH, PA,
                                                                 TN, VA, WV, WI);
                                                                 Canada (ON).
 
                                                                      * * * * * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------


[[Page 8665]]

* * * * *

    Dated: January 26, 2012.
Hannibal Bolton,
Acting Director, U.S. Fish and Wildlife Service.
[FR Doc. 2012-2940 Filed 2-13-12; 8:45 am]
BILLING CODE 4310-55-P