[Federal Register: November 2, 2010 (Volume 75, Number 211)]
[Proposed Rules]
[Page 67551-67583]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr02no10-26]
[[Page 67551]]
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Part IV
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; Listing the Rayed Bean
and Snuffbox as Endangered; Proposed Rule
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DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 17
[Docket No. FWS-R3-ES-2010-0019; MO 92210-0-0008-B2]
RIN 1018-AV96
Endangered and Threatened Wildlife and Plants; Listing the Rayed
Bean and Snuffbox as Endangered
AGENCY: Fish and Wildlife Service, Interior.
ACTION: Proposed rule.
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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), propose to
list the rayed bean (Villosa fabalis) and snuffbox (Epioblasma
triquetra) as endangered throughout their ranges, under Endangered
Species Act of 1973, as amended (Act). This proposed rule, if made
final, would extend the Act's protection to the rayed bean and the
snuffbox. We have determined that designating critical habitat for
these species is prudent, but not determinable at this time. The
Service seeks data and comments from the public on this proposed
listing rule.
DATES: We will consider comments we receive on or before January 3,
2011. We must receive requests for public hearings, in writing, at the
address shown in the FOR FURTHER INFORMATION CONTACT section on or
before December 17, 2010.
ADDRESSES: You may submit comments by one of the following methods:
Federal eRulemaking Portal: http://www.regulations.gov.
Follow the instructions for submitting comments on Docket No. FWS-R3-
2010-0019.
U.S. mail or hand-delivery: Public Comments Processing,
Attn: FWS-R3-2010-0019; Division of Policy and Directives Management;
U.S. Fish and Wildlife Service; 4401 N. Fairfax Drive, Suite 222;
Arlington, VA 22203.
We will post all comments on http://www.regulations.gov. This
generally means that we will post any personal information you provide
us (see the Public Comments section below for more information).
FOR FURTHER INFORMATION CONTACT: Angela Boyer at the U.S. Fish and
Wildlife Service, Ohio Ecological Services Field Office, 4625 Morse
Road, Suite 104, Columbus, OH 43230; telephone 614-416-8993, ext. 22.
SUPPLEMENTARY INFORMATION:
Public Comments
Our intent is to use the best available commercial and scientific
data as the foundation for all endangered and threatened species
listing determinations. We therefore request comments or suggestions
from other concerned governmental agencies, the scientific community,
industry, or any other interested party concerning this proposed rule
to list the rayed bean and snuffbox as endangered. We particularly seek
comments concerning:
(1) Survey results for the rayed bean or snuffbox, as well as any
studies that may show distribution, status, population size, or
population trends, including indications of recruitment;
(2) Pertinent aspects of life history, ecology, and habitat use of
the rayed bean or snuffbox;
(3) Current and foreseeable threats faced by the rayed bean or
snuffbox, or both species, in relation to the five factors (as defined
in section 4(a)(1) of the Act (16 U.S.C. 1531 et seq.));
(4) The specific physical and biological features to consider, and
specific areas that may meet the definition of critical habitat and
that should or should not be considered for a proposed critical habitat
designation as provided by section 4 of the Act; and
(5) The data and studies to which this proposal refers.
You may submit your comments and materials concerning this proposed
rule by one of the methods listed in the ADDRESSES section. We will not
accept comments sent by e-mail or fax or to an address not listed in
the ADDRESSES section. Comments must be submitted to http://
www.regulations.gov before midnight (Eastern Time) on the date
specified in the DATES section. Finally, we will not consider hand-
delivered comments that we do not receive, or mailed comments that are
not postmarked, by the date specified in the DATES section.
We will post your entire comment --including your personal
identifying information--on http://www.regulations.gov. If you provide
us personal identifying information such as your street address, phone
number, or e-mail address, you may request at the top of your document
that we withhold this information from public review. However, we
cannot guarantee that we will be able to do so.
Comments and materials we receive, as well as supporting
documentation we used in preparing this proposed rule, will be
available for public inspection on http://www.regulations.gov, or by
appointment, during normal business hours at the Ohio Ecological
Services Field Office (see FOR FURTHER INFORMATION CONTACT).
Public Hearing
The Act provides for one or more public hearings on this proposal,
if requested. We must receive requests by the date listed in the DATES
section above. Such requests must be made in writing and addressed to
the Field Supervisor of the Ohio Ecological Services Field Office (see
FOR FURTHER INFORMATION CONTACT).
Background
Species Descriptions
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 hinge line 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 is its small size, thick valves, unusually heavy
teeth for a small mussel, and color pattern (Cummings and Mayer 1992,
p. 142).
The snuffbox is a small- to medium-sized mussel with males reaching
up to 2.8 in. (7.0 cm) in length (Cummings
[[Page 67553]]
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, 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 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.
The type locality 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 of the snuffbox was summarized by
Johnson (1978, pp. 248-249), Parmalee and Bogan (1998, p. 108), and Roe
(no date, 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 are 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. 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 among and within species (0-9 years) (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). The only published research identifies the
Tippecanoe darter (Etheostoma tippecanoe) as a 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
[[Page 67554]]
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, pp. 244). They are usually found
in or near shoal or riffle 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, pp. 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 displayed 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. He 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 112 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 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 28 streams and
1 lake in six States and one Canadian province: Indiana (St. Joseph
River (stream) (Fish Creek (tributary)), 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, French 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 (Cussewago Creek))), 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 from only 28 streams and 1
lake (down from 112), a 74 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,
Tennessee, and Virginia. The rayed bean was also extirpated in West
Virginia until the 2006 reintroduction into the Elk River (Clayton
2007, pers. comm.).
In this proposed rule, mussel shell collection records have been
classified according to the condition of shell material. Fresh dead
(FD) 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 (R) 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, FD shells indicate the
continued presence of the species at a site (Metcalf 1980, p. 4). The
presence of R shells only, along with repeated failure to find live (L)
animals or FD 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 it is reproducing and
has enough individuals to sustain the population at its current level
for the foreseeable future.
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Table 1--Rayed Bean Status at Historical Locations
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Last observed (R =
River basin Stream relic) Current status Comments
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Upper Great Lakes Sub-basin.... Pigeon River...... 1996 (R) Extirpated........ ..................
Lower Great Lakes Sub-basin.... Black River....... 2001 Unknown........... Small and of
questionable
viability.
Mill Creek........ 2002 Unknown........... Unknown.
Pine River........ 2002 Declining......... Recruiting.
Belle River....... 2003 Unknown........... ..................
Clinton River..... 1992 Unknown........... Recruiting.
North Fork Clinton 1933 Extirpated........ ..................
River.
Sydenham River 2003 Stable............ Recruiting.
(Canada).
Thames River...... 2008 Unknown........... Unknown.
Detroit River..... 1983 Extirpated........ ..................
Rouge River....... <1914 Extirpated........
Huron River....... 1931-32 Extirpated........
Raisin River...... 1941 Extirpated........
Macon Creek....... 1976-78 (R) Extirpated........
Maumee River...... 1913 Extirpated........
Swan Creek........ 2009 Stable............ Recruiting.
St. Joseph River.. 1998 Declining......... Probably not
recruiting.
West Branch St. 1997 (R) Extirpated........
Joseph River.
Fish Creek........ 2009 Declining......... Unknown.
Cedar Creek....... 1985 Extirpated........
Feeder Canal to 1988 (R) Extirpated........
St. Joseph River.
Auglaize River.... 1964 Extirpated........
Ottawa River...... 1998 (R) Extirpated........
Blanchard River... 2009 Unknown........... Recruiting.
Sandusky River.... 1978 Extirpated........
Tymochtee Creek... 1996 Unknown........... Unknown.
Wolf Creek........ 1971 (R) Extirpated........
Lake Erie......... 1977-87 Extirpated........
Ohio River system.............. Ohio River <1960 Extirpated........
mainstem.
Allegheny River... 2007 Stable............ Recruiting.
Chautauqua Lake <1919 Extirpated........
outlet.
Chautauqua Lake... <1919 Extirpated........
Olean Creek....... 2000 Unknown........... Recruiting.
Cassadaga Creek... 1994 Unknown........... Recruiting.
Conewango Creek... ~1908 Extirpated........
Oil Creek......... <1970 Extirpated........
French Creek...... 2005 Stable............ Recruiting.
Cussewago Creek... 1991 Unknown...........
Crooked Creek..... ~1908 Extirpated........
West Fork River... <1913 Extirpated........
Beaver River...... ~1910 Extirpated........
Shenango River.... ~1908 Extirpated........
Pymatuning Creek.. ~1908 Extirpated........
Mahoning River.... <1921 Extirpated........
Middle Island 1980 (R) Extirpated........
Creek.
Muskingum River... 1980 (R) Extirpated........
Tuscarawas River.. ? Extirpated........
Walhonding River.. 1991-95 Declining......... Probably not
recruiting.
Mohican River..... 1969 Extirpated........
Elk River......... 2008 Reintroduced in
2006.
Scioto River...... 1964 Extirpated........
Mill Creek........ 2007 Unknown...........
Alum Creek........ 1970 Extirpated........
Blacklick Creek... ? Extirpated........
Olentangy River... 1962 Extirpated........
Whetstone Creek... 1961 Extirpated........
Big Walnut Creek.. 1961 Extirpated........
Walnut Creek...... 1994 (R) Extirpated........
Big Darby Creek... 2008 Declining......... Unknown.
Little Darby Creek 1990 (R) or 1986 Extirpated........
(R)
Deer Creek........ 1981 Extirpated........
Sugar Creek....... <1900 Extirpated........
Scioto Brush Creek 1987 Unknown........... Probably not
recruiting.
Cedar Creek....... ? Extirpated........
Buckeye Lake...... ? Extirpated........
Ohio and Erie ? Extirpated........ ..................
Canal.
Great Miami River. 2009 Unknown........... Unknown.
Little Miami River 1990-91 Unknown........... Probably not
recruiting.
East Fork Little 1990-91 Unknown...........
Miami River.
[[Page 67556]]
Stillwater River.. 1987 Unknown........... Probably not
recruiting.
South Fork Licking 1982 (R) Extirpated........
River.
North Fork Elkhorn 1982 (R) Extirpated........
Creek.
Eagle Creek....... 1981 (R) Extirpated........
Brashears Creek... 1983 (R) Extirpated........
Green River....... 1964 Extirpated........
Nolin River....... 1983 (R) Extirpated........
Barren River...... <1900, ? Extirpated........
Wabash River...... 1962 (R) Extirpated........
Salamonie River... 1971 Extirpated........
Mississinewa River 1994 (R) Extirpated........
Tippecanoe River.. 1995 Declining......... Possibly
recruiting.
Tippecanoe Lake... <1920 Extirpated........
Winona Lake....... 1934 Extirpated........
Pike Lake......... 1906 Extirpated........
Lake Maxinkuckee.. 1997 Declining......... Unknown.
Vermilion River... 1999 (R) Extirpated........
Salt Fork 1956-57 Extirpated........
Vermilion River.
Middle Fork 1991 Extirpated........
Vermilion River.
North Fork 1995 (R) Extirpated........
Vermilion River.
Embarras River.... 1956 Extirpated........
Sugar Creek....... 1998 Unknown........... Unknown.
White River....... <1903 Extirpated........
West Fork White 1989-91 (R) Extirpated........
River.
East Fork White ? Extirpated........
River.
Big Blue River.... 1944 Extirpated........
Walnut Creek...... 1992 (R) Extirpated........
Mill Creek........ 1992 (R) Extirpated........
Fall Creek........ ? Extirpated........
Sugar Creek....... 1950 Extirpated........
Tennessee River system......... Tennessee River <1939 Extirpated........
mainstem.
Holston River..... 1914-15 Extirpated........
North Fork Holston 1913 Extirpated........
River.
South Fork Holston 1914 Extirpated........
River.
Nolichucky River.. 1968 Extirpated........
Lick Creek........ 1967 (R) Extirpated........
First Creek....... ? Extirpated........
Clinch River...... 1965 Extirpated........
North Fork Clinch <1921 Extirpated........
River.
Powell River...... 1913-15 Extirpated........
Elk River......... 1965 Extirpated........
Richland Creek.... 1892 Extirpated........
Duck River........ 1982 Extirpated........
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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 a tributary to
the St. Joseph River, a tributary to Lake Michigan. No extant
populations of the rayed bean are currently known from this system.
Lower Great Lakes Sub-Basin
Of the 112 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, but failed to find the rayed
bean. The rayed bean was not discovered there until the summer of 2001
when a single live (L) 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.
[[Page 67557]]
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 L individuals and 23 FD 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 L
individuals were found. The last survey in the Pine River occurred in
2002 (Badra 2008, pers. comm.), and one L rayed bean was documented
(Badra and Goforth 2003, p. 6). The species may have declined
significantly since the 1980s, but 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 FD specimens
were collected (OSUM 1965:0106). The same site was revisited in 1978,
but only one FD shell is represented in OSUM 1978:0013. Since that
time, L individuals or FD specimens have been found in 1983 and 1992,
while only R shells were found in 1994 (Badra 2008, pers. comm.).
During summer 2002 sampling, single L specimens were found at two new
sites, with an additional four and two FD specimens, respectively, also
found from these sites (Badra 2008, pers. comm.). The status of the
population is still not well known, but appears to be small.
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 L individuals
using a suction dredge from a bridge site slated for widening where
Strayer (1980, p. 146) found only R shells. The rayed bean represented
1.2 percent relative abundance of the 10 species collected at the site.
The population is probably viable but currently restricted to about 3
mi (4.8 km) of stream in the western suburbs of Pontiac. Its long-term
status appears to be highly precarious.
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 L and FD material they gathered, West et al. (2000, p. 256)
considered the population to be ``healthy'' and ``reproducing''
(recruiting). Data from sampling in 2001 shows evidence of 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)
estimates 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 (full of eggs) females were collected at two north
branch sites (Woolnough 2008, pers. comm.). In September 2008, four L
females and two L 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) estimates 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 FD 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 L individuals and FD
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 L and three FD
rayed bean in 2005 at the County Road 3 bridge in Ohio. In 2009, two FD
rayed bean were found in lower Fish Creek in Ohio (personal
observation). The viability and status of this population is 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
[[Page 67558]]
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. 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
FD 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 L 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 71 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
16 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 wholesale destruction of
mussels in several streams (Ortmann 1909b, pp. 11-12). It currently
occurs in Pennsylvania downstream of Allegheny (Kinzua) Reservoir in
Warren County to the pool of Lock and Dam 8 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 L individual was located with R shells from the other two sites.
Only R shells were found in Olean Creek in 1994, but three L
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 L 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 L 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 L specimens were found in 1994
(Strayer 1995). Muskrat middens collected during the winter of 2002
produced 38 FD 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. The
highly restricted extent of the population combined with its proximity
to roads and retail development, including a gas station close to the
flood zone upstream, makes it extremely susceptible to a stochastic
event (such as a toxic chemical spill).
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 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
Vanango. 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).
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 L
individual and one FD specimen at one site, while four R 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-
[[Page 67559]]
minute search yielded two L individuals, but efforts were discontinued
due to high water and excessive habitat disturbance caused by the
search effort (Clayton 2008, 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 meta-population 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 meta-population 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 FD specimens were
found during a survey in the City of Marysville (Hoggarth 2005, p. 7).
In 2007, Hoggarth (2007a, pp. 5-6) found two L rayed bean at the same
site and one L 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 FD specimens in 1986, but none in 1990, and
indicated that the rayed bean was probably extirpated from Big Darby
Creek. In 2006, one L individual was 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 L individuals were subsequently found at
the relocation site (Hoggarth 2006, p. 6). In 2007, three L 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 FD and two R specimens from a site, and a R
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 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 L
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 FD specimens were reported from a site
in eastern Clermont County in 1973. Hoggarth (1992, p. 265) reported
one L, three FD, and one R 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 FD and one R, 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.
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 FD 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 FD 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 and 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
[[Page 67560]]
1930. Harmon (1992, p. 33) sampled 27 mainstem and 16 tributary sites
finding FD specimens at 3 mainstem sites and R specimens from 2 other
sites. The sites with FD 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 L rayed bean records from the system, with the
exception of the Duck River, were from the 1960s or earlier. The
species held on in the Duck until the early 1980s. Recent intensive
sampling in the Duck watershed has failed to locate even a R shell of
the rayed bean (Ahlstedt et al. 2004, p. 29). Tributaries in this
system have been extensively sampled over the past 25 years. It is
highly probable that this species is extirpated from the entire
Tennessee River system.
A project was initiated in 2008 to reintroduce rayed bean into the
Duck River by translocating over 1,000 adults from the Allegheny River
system. Although the rayed bean was extirpated from the Duck River
about 25 years ago, major improvements in water 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 reintroduction
has not yet occurred.
The information presented in this document 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, Swan, Blanchard, and Allegheny Rivers, and
French Creek). 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 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 208 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. 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 74 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, Maple River, Pine
River, Belle River, Clinton River, Huron River, Davis Creek, South Ore
Creek, and Portage River), Minnesota (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, Muddy Creek,
Conneaut Outlet, Little Mahoning Creek, Dunkard 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, Dunkard Creek, Middle Island Creek, North Fork
Hughes River, and Elk River), Wisconsin (St. Croix River, Wolf River,
Embarrass River, Little Wolf River, and Willow Creek), and Ontario
(Ausable River and Sydenham River). It is probable that the species
persists in some of the 134 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 from only 74 streams (down
from 208 historically), representing a 65 percent decline in occupied
streams (Table 2). Since multiple streams may comprise a single
snuffbox population (French Creek system), the actual number of extant
populations is less than 74. Extant populations, with few exceptions,
are highly fragmented and restricted to short reaches. Available
records indicate that 24 of 74, or 33 percent, of streams considered to
harbor extant populations of the snuffbox are represented by only one
or two recent L or FD individuals (Embarrass, Little Wolf, Maple,
Pigeon, Kankakee, Meramec, Ohio, Muskingum, Olentangy, Stillwater,
Green, Powell, Duck, and Black Rivers; and Little Mahoning, Middle
Island, Big Darby, Little Darby, Salt, South Fork Scioto Brush, Slate,
and Buck (Indiana), Graham, Buck (Kentucky) Creeks.
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 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 6 stronghold populations, 23 significant
populations,
[[Page 67561]]
and 45 marginal populations of snuffbox.
A population is considered extant if L individuals or FD 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--Snuffbox Extant Stream Population Summary by Stream of Occurrence
--------------------------------------------------------------------------------------------------------------------------------------------------------
Last Potential
Stream (state) observed Recruiting viability Population size Population trend Status category
--------------------------------------------------------------------------------------------------------------------------------------------------------
Wolf River (WI)................ 2006 Yes............... High.............. Large............. Declining......... Stronghold.
Embarrass River (WI)........... 1995 ?................. ?................. Small............. ?................. Marginal.
Little Wolf River (WI)......... 1999 ?................. ?................. Small............. ?................. Marginal.
Willow Creek (WI).............. 2001 ?................. ?................. Small............. ?................. Marginal.
Grand River (MI)............... 2002 Yes............... High.............. Medium............ ?................. Significant.
Maple River (MI)............... 2001 ?................. ?................. Small............. ?................. Marginal.
Pine River (MI)................ 2002 ?................. Low............... Small............. Stable............ Marginal.
Belle River (MI)............... 2002 Yes............... High.............. Small............. ?................. Significant.
Clinton River (MI)............. 2003 Yes............... High.............. Large............. Declining......... Significant.
Huron River (MI)............... 2001 ?................. Low............... Medium............ ?................. Significant.
Davis Creek (MI)............... 2005 Yes............... High.............. Medium............ ?................. Significant.
South Ore Creek (MI)........... 1999 Yes............... High.............. Small............. ?................. Significant.
Portage River (MI)............. 1998 Yes............... High.............. Medium............ ?................. Significant.
Grand River (OH)............... 2006 Yes............... High.............. Medium............ ?................. Significant.
St. Croix River (MN and WI).... 2004 Yes............... High.............. Large............. Declining......... Significant.
Kankakee River (IL)............ 1991 ?................. ?................. Small............. ?................. Marginal.
Meramec River (MO)............. 1997 ?................. ?................. Small............. Declining......... Marginal.
Bourbeuse River (MO)........... 2006 Yes............... High.............. Large............. Improving......... Stronghold.
Ohio River (OH)................ 2001 ?................. Low............... Small............. ?................. Marginal.
Muskingum River (OH)........... 2005 ?................. ?................. Small............. ?................. Marginal.
Walhonding River (OH).......... 1991 ?................. ?................. Small............. Declining......... Significant.
Killbuck Creek (OH)............ 2009 ?................. ?................. Small............. Declining......... Marginal.
Olentangy River (OH)........... 1989 ?................. ?................. Small............. Declining......... Marginal.
Big Darby Creek (OH)........... 2008 ?................. ?................. Small............. Declining......... Marginal.
Little Darby Creek (OH)........ 1999 ?................. ?................. Small............. Declining......... Marginal.
Salt Creek (OH)................ 1987 ?................. ?................. Small............. ?................. Marginal.
Scioto Brush Creek (OH)........ 1987 ?................. ?................. Small............. ?................. Marginal.
South Fork Scioto Brush Creek 1987 ?................. ?................. Small............. ?................. Marginal.
(OH).
Little Miami River (OH)........ 1991 ?................. ?................. Small............. ?................. Marginal.
Stillwater River (OH).......... 1987 ?................. ?................. Small............. ?................. Marginal.
Pigeon River (IN).............. 1998 ?................. ?................. Small............. ?................. Marginal.
Salamonie River (IN)........... 2004 Yes............... Low............... Small............. ?................. Significant.
Tippecanoe River (IN).......... 2003 ?................. ?................. Small............. Declining......... Marginal.
Embarras River (IL)............ 2008 Yes............... Low............... Small............. Declining......... Significant.
Sugar Creek (IN)............... 1990 ?................. ?................. Small............. Declining......... Marginal.
Buck Creek (IN)................ 1990 ?................. ?................. Small............. ?................. Marginal.
Muscatatuck River (IN)......... 1988 ?................. ?................. Small............. ?................. Marginal.
Graham Creek (IN).............. 1990 ?................. ?................. Small............. Declining......... Marginal.
St. Francis River (MO)......... 2006 Yes............... High.............. Medium............ Stable............ Significant.
Black River (MO)............... 2002 Yes............... Low............... Small............. ?................. Significant.
Tygarts Creek (KY)............. 1995 ?................. ?................. Small............. Declining......... Marginal.
Kinniconick Creek (KY)......... 2005 ?................. Low............... Small............. Declining......... Marginal.
Licking River (KY)............. 2006 ?................. Low............... Small............. ?................. Marginal.
Slate Creek (KY)............... 1992 ?................. ?................. Small............. Declining......... Marginal.
Middle Fork Kentucky River (KY) 1997 ?................. ?................. Small............. ?................. Marginal.
[[Page 67562]]
Red Bird River (KY)............ 1995 ?................. ?................. Small............. ?................. Marginal.
Red River (KY)................. ~2002 ?................. ?................. Small............. ?................. Significant.
Rolling Fork Salt River (KY)... ~2005 ?................. ?................. Small............. ?................. Marginal.
Green River (KY)............... 1989 ?................. ?................. Small............. Declining......... Marginal.
Buck Creek (KY)................ 1987-90 ?................. ?................. Small............. Declining......... Marginal.
Clinch River (TN and VA)....... 2006 Yes............... High.............. Large............. Stable or Stronghold.
Declining.
Powell River (TN and VA)....... 2008 ?................. ?................. Small............. Declining......... Marginal.
Tennessee River (AL)........... 2006 ?................. ?................. Small............. ?................. 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 ?................. ?................. Small............. ?................. Marginal.
Buffalo River (AR)............. 2006 ?................. ?................. Small............. ?................. Marginal.
Spring River (AR).............. 2005 ?................. Low............... Medium............ ?................. Significant.
Strawberry River (AR).......... 1997 ?................. ?................. Small............. ?................. Marginal.
Allegheny River (PA)........... 2001 ?................. ?................. Small............. ?................. Marginal.
French Creek (PA).............. 2008 Yes............... High.............. Large............. Stable............ Stronghold.
West Branch French Creek (PA).. 2008 ?................. ?................. Small............. ?................. Marginal.
Le Boeuf Creek (PA)............ 2006 Yes............... Low............... Small............. ?................. Marginal.
Muddy Creek (PA)............... 2008 Yes............... Low............... Medium............ ?................. Significant.
Conneaut Outlet (PA)........... 1997 ?................. ?................. Small............. ?................. Marginal.
Little Mahoning Creek (PA)..... 1991 ?................. ?................. Small............. ?................. Marginal.
Dunkard Creek (PA and WV)...... 2009 ?................. ?................. Small............. Declining......... Significant.
Shenango River (PA)............ 2002 ?................. ?................. Small............. ?................. Marginal.
Little Shenango River (PA)..... 2002 ?................. ?................. Small............. ?................. Significant.
Middle Island Creek (WV)....... 2001 ?................. ?................. Small............. Declining......... Marginal.
North Fork Hughes River (WV)... 2001 ?................. Low............... Small............. Declining......... Significant.
Elk River (WV)................. 2004 ?................. Low............... Medium............ Improving......... Significant.
Ausable River (ON)............. 2006 Yes............... High.............. Medium............ Declining......... Significant.
Sydenham River (ON)............ 2002 Yes............... High.............. Large............. ?................. Stronghold.
--------------------------------------------------------------------------------------------------------------------------------------------------------
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 seven 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 L individuals and two dead specimens during
1987-1988 and a single D 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
[[Page 67563]]
Wolf River in Waupaca County, Wisconsin. The snuffbox is known from a
single L individual collected in 1988 at RM 14 below the Mill Pond dam
at Manawa (Butler 2007, p. 22). Five D 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 L
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 have a
low level of viability, with recruitment noted in 1999 (Badra 2008,
pers. comm.).
Maple River--The Maple River is a northeastern tributary of the
Grand River draining south-central Michigan. A single snuffbox record
(one L 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 FD 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 R shells were found at three of nine sites sampled in 2004
(Butler 2007, p. 24). The snuffbox 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 L and FD 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 Ontario.
The lack of impounded area on these streams has likely prevented the
introduction or the establishment of zebra mussels (Ausable River
Recovery Team 2005, p. 12; Dextrase et al. 2000, p. 10). The snuffbox
is considered extant in 10 streams of the lower Great Lakes sub-basin,
including a stronghold population in the Sydenham River and sizable but
reach-limited populations in the Clinton River and Davis Creek. A
single FD 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 2006 found that a sizable population of snuffbox occurs in the lower
portion of the stream in over 23 river mi (37 river km) (McGoldrick
2007, pers. comm.). The size range of individuals found in the 2006
survey indicates recent recruitment in the viable population
(McGoldrick 2007, pers. comm.; Staton 2007, 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 L and FD
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). 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) 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 D shells) and 1991
(Butler 2007, p. 28). During the 1997-99 sampling, a total of 10 L and
FD 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 1997-98 (Metcalfe-Smith et al.
2000, p. 728). More recent sampling found 57 L and FD individuals from
21 collection events (some individuals may have been counted multiple
times) at six sites during 2000-02. 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
[[Page 67564]]
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 L, 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 FD 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 no date, p. 6), with early surveys
summarized by van der Schalie and van der Schalie (1950, p. 456). The
species was reported L 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)) and is now extirpated
from the mainstem of the Mississippi River (Havlik and Sauer 2000, p.
4). Only 4 of 17 historical 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.
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
(NSPD) 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 six stronghold 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 Will County, Illinois, sites; 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 FD specimens in Illinois
(Will County in 1988, Kankakee County in 1991) were subsequently found.
Only R 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 FD specimens at three sites and R 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
FD specimens at RM 33.5, 48.8, and 59.8; and one L individual at RM
39.8. The L 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.).
[[Page 67565]]
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, which collectively represented the
largest block of available habitat for this species. 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 40 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 FD and L
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 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, pp. 3-9). Live and FD 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 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 L
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 FD and
6 R shells were reported in 1988 (Evans 2003b, pers. comm.), and 1 L,
16 FD, and 8 R specimens were found in 1991 (Butler 2007, p. 40). Three
L individuals were found at a site in 2006 (Smith 2006, pers. comm.).
The snuffbox population has recently recruited and exhibits some level
of viability, but appears to be very limited in extent.
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.). Low numbers were
found at most sites, but 18 L individuals were collected from a site
near the mouth. This occurrence is considered to be part of the more
extensive French Creek snuffbox population. Zimmerman (2008c, pers.
comm.) documented one L 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.).
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 L 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 of Little Mahoning
Creek is 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. Viability is unknown.
Dunkard Creek--Dunkard Creek is an easterly flowing, western
tributary of the middle Monongahela River, straddling the Pennsylvania
and West Virginia State lines. Snuffbox records occur in both States
from several museum collections from 1969-74. Small numbers of
specimens, of undocumented condition, were found at four sites during
1993-94 sampling in Pennsylvania (Bogan 1993, p. 8; Evans 2003b, pers.
comm.). Eight specimens, of undocumented condition, were collected at a
West Virginia site in 1997. On September 1, 2009, a fish kill was
reported in Dunkard Creek due to an unknown cause (Clayton 2009, pers.
comm.). The Upper Monongahela River Association (2009) reported that
161 aquatic species including fish, mussels, and plants died along
Dunkard Creek due to this toxic event. According to Clayton (2009,
pers. comm.), the event may have killed 100 percent of the mussel fauna
in the entire stream. The status of this population is not known at
this time, but the snuffbox may now be extirpated from Dunkard Creek.
Shenango River--The Shenango River is a large tributary in the
Beaver River system, a northern tributary of the upper Ohio River in
west-central Pennsylvania. The snuffbox was
[[Page 67566]]
reported from four sites on the Shenango in 1908 (Ortmann 1919, p.
328). Six L individuals were collected from three sites sampled in
2001-02 between Jamestown and New Hamburg (about 25 river mi (40.2
river km)). 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.).
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 FD 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 record
was for a single L individual collected in Tyler County in 2001
(Zimmerman 2008b, pers. comm.). This snuffbox population has declined,
is currently rare, and its viability is questionable (Zimmerman 2008b,
pers. comm.).
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 L individuals and two FD shells were
found in 1979, but no L or FD 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 L specimen was located during sampling for a
construction project in 2005 near Dresden (Taylor 2006, pers. comm.).
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 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 FD 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 L adults were found at 2 sites
approximately 3 river mi (4.8 river km) apart, while 9 large L
individuals and a single FD specimen were collected near RM 13 during
fall 2006 (Ahlstedt 2007, pers. comm.; Butler 2007, p. 45). 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.
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 1981-82 survey of the Little
Kanawha River system (Schmidt et al. 1983). A total of 41 L 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 L individuals were found at a
site in the park in 1997 (Butler 2007, p. 46), and a single FD 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 L individuals were collected
during 1991-1995, the smallest being about 5 years old (Butler 2007,
pp. 46-47). Collectively, 16 L individuals were identified at 8 sites
in a 13-river-mi (20.9-river-km) reach in Kanawha County in 2002, and 4
L individuals were found at 4 sites in 2004 over a 16.8-river-mi (27-
river-km) reach further 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). FD specimens are also known from 1981 and 1987 (Cicerello 2003,
pers. comm.). Nine L (Butler 2007, p. 47) and 36 FD specimens were
found at 2 sites, respectively, in 1988, while 1 L and 2 FD 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 (WWTP) 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.
[[Page 67567]]
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 1960-61 survey, when it
appeared ``fairly common'' in the lower river (Stein 1963, p. 138). A
single L individual in southern Delaware County and two FD specimens in
eastern Marion County were found among 30 sites in 1989, with R shells
at 7 other sites (Hoggarth 1990, pp. 20-27). The small population has
declined (Hoggarth 1990, p. 14), and 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 L and FD 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 L and FD
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 L and FD specimens was reduced
from 54 to 16 and its distribution declined from 17 to 8 sites. Two FD
specimens were found at sites in Franklin (1996) and Pickaway (2000)
Counties, and three other sites produced only R 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 five specimens per lot), date to the
early 1960s, and represent lower mainstem sites in Madison County.
Single FD and R specimens were collected in 1999 from a Union County
site (OSUM 66740), where L individuals were collected in 1964 (Stein
1966, p. 23). This site yielded only R 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 L 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 Bush 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
L and FD specimens from 2 sites and R 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 was reported L
from 4 of 15 sites sampled in 1982 with R shells from an additional 2
sites (Warren et al. 1984, pp. 48-49). Single FD and L snuffbox were
collected in 2001 and 2004, respectively, from sampling efforts at
several sites (Butler 2007, p. 51), and a single FD specimen was found
while resurveying four sites in 2005 (Butler 2007, p. 51). The snuffbox
declined in the past few decades, 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 FD specimens were
found at 4 of 46 mainstem sites surveyed during 1990-91, with 10 R
shells at 6 other sites (Hoggarth 1992, p. 265). The FD 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 L individual and a FD specimen
were found at 2 sites and R shells were reported from 7 other sites
among 49 sites sampled in 1991 (Laudermilk 1993, p. 45). Single L and
FD snuffbox were collected in 1999 (Cicerello 2003, pers. comm.), and a
single L individual was found in 2006 (Butler 2007, p. 53). The
snuffbox has become very rare, 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 D specimens were recorded from a
site in 1987 (Cicerello 2003, pers. comm.). A single FD and seven R
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 L individuals were found in 1992 (Cicerello 2003,
pers. comm.). Subsequent sampling has produced no additional snuffbox;
two sites and four sites yielded only R 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 FD specimen below
Englewood Dam in Montgomery County was found among 18 sites surveyed in
1987, with R 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
[[Page 67568]]
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 L individuals and a R shell were found at three sites in
1996, and a single L 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 FD
specimens were recorded from two sites in 1988, and three L and one FD
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 L
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 FD and one L snuffbox were found at
three sites in 1988, while five L individuals were found in 1996
(Cicerello 2006, pers. 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 FD specimens
and a single L 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 1998-99 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 1961-66, but only six R
shells were reported there in 1967. The snuffbox has been rare since.
Five L and FD snuffbox were collected at 4 of 42 sites during 1987-89
sampling in Mammoth Cave National Park (Cicerello and Hannan 1990, pp.
16-17). Three L and six FD snuffbox were reported in the upper Green
River from 1984-90 (Cicerello 2003, pers. comm.). A single L 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 1993-94 without finding any evidence of the
snuffbox (ESI 1995, p. 19). The snuffbox was rediscovered in 2004 above
Salamonie Reservoir, where two L individuals at one site and FD 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 1991-92 (ESI 1993, p. 68). One L
individual and over 32 FD 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 FD
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 L and 15 FD
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 L and three FD 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 has declined
to some extent. Recent surveys, however, documented only one L
individual in 2005 and one L and one FD in 2008, indicating that the
Embarras River population may be closer to a marginal population than a
significant one (Tiemann 2009, pers. comm.).
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 L individual from one site, FD specimens from
seven sites, and R shells from an additional eight sites were reported
in 1990 (Harmon 1992, pp. 40-41 1998). The snuffbox population
[[Page 67569]]
occurred sporadically over 35 river mi (56 km) to near the mouth. Only
R 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 FD snuffbox was found near the mouth and R 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). FD 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 FD (numbers unknown) at six
sites over 10 river mi (16 river km) of the lower stream in Jennings
County in 1988 (Harmon 1989, p. 117), and a single FD specimen was
found in 1990 (Harmon 1998). Viability of these small population 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 D valve was found at a site in 1981 (Clarke 1981b,
Appendix), and two L and one FD snuffbox were reported from three sites
during 1983-84 (Schuster et al. 1989, p. 82). The species was also
reported L from a lower mainstem site among seven sites sampled from
1987-90 (Layzer and Anderson 1992, p. 16). A recent survey found only R
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 L
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 Knoxville
in northeastern Tennessee. No other river in North America has extant
populations of more federally endangered (15) and candidate (4) 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 1965-71
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 1973-78 by Dennis (1981, p. 3), four
sites from 1975-78 by Ahlstedt and Brown (1979, p. 42), and four
Virginia sites in 1988-89 by Wolcott and Neves (1994, p. 7). Large
collections attest to its former abundance. The species was found L and
FD in the Powell River, Tennessee, during 1989-90 (Hubbs et al. 1991,
Appendix A). Johnson (2008) collected two L individuals at RM 95. 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 Tennesssee River.''
However, Yokley (2002, p. 1) collected a single FD male in 2002 at the
U.S. 231 Bridge, Madison and Morgan Counties. In 2006, one L female was
found at the same location, though 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 1965-67 (Isom and
Yokley 1973, p. 444) and a 1980 survey (Butler 2007, p. 64). Twelve L
and FD snuffbox were found at four sites between RMs 13 and 21
(Ahlstedt 1995-96, p. 70). The species was again absent from 10 upper
mainstem sites surveyed in 2002 (Godwin 2002, p. 9). Four FD 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 L and 11 FD specimens were found at RM 21 in 2005,
and 2 L and 16 FD were collected at RM 31 in 2007 (Gangloff 2007, pers.
comm.). In July 2008, Freeman (2008, pers. comm.) observed multiple age
classes (sizes) of FD snuffbox in middens between RM 34.7 and 32.5.
Fobian et al. (2008, p. 14) collected 21 L snuffbox at 7 sites and FD
specimens at 8 sites between RM 46.7 and 13.1. The stronghold snuffbox
population exists between RMs 13 and 44, and is
[[Page 67570]]
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 L 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 FD specimen
was found at RM 51 among 4 sites sampled in 2001 (Hubbs 2002, p. 5;
Butler 2007, p. 65). A single L and a FD 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 FD specimens at Stairstep Shoals in Giles County, Tennessee,
in July 2007. The small snuffbox population has recently recruited,
exhibits some level of viability, and its numbers appear relatively
stable in recent history.
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 L individuals
were collected from 2 of 99 sites surveyed in 1979 (Butler 2007, p.
66). A single L individual was discovered in Maury County among 72
sites sampled during 2000-03 (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 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 a single stream in this sub-basin, outside of the White River
system.
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 L
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) and 1995 (40 sites; Harris 1996, p. 9), but two L
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 L 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. The 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 L adult male was found in Lawrence County
in 2005, and represents the first L specimen found in Arkansas in more
than 20 years (Butler 2007, p. 69). Further, 53 FD 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 of unknown
viability.
Summary of Snuffbox Population Estimates and Status
The snuffbox has declined rangewide and appears to be extant in 74
of 208 streams and lakes of historical occurrence, a 65 percent decline
in occupied streams. Realistically, much more than 65 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. Since 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.
[[Page 67571]]
Previous Federal Action
We identified the rayed bean as a Category 2 species in a notice of
review published in the Federal Register on May 22, 1984 (49 FR 21664).
The rayed bean remained a Category 2 species in subsequent notices
including January 6, 1989 (54 FR 554), November 21, 1991 (56 FR 58804),
and November 15, 1994 (59 FR 58982). Prior to 1996, a Category 2
species was one that we were considering for possible addition to the
Federal List of Endangered and Threatened Wildlife but for which
conclusive data on biological vulnerability and threats were not
available to support a proposed rule. We stopped designating Category 2
species in the February 28, 1996, Notice of Review (61 FR 7596). We now
define a candidate species as a species for which we have on file
sufficient information to propose it for protection under the Act. We
designated the rayed bean as a candidate species on May 4, 2004 (69 FR
24876).
We identified the snuffbox as a Category 2 species in the notice of
review published in the Federal Register on November 21, 1991 (56 FR
58804). The snuffbox remained a Category 2 in the subsequent notice on
November 15, 1994 (59 FR 58982) but was dropped from the list in the
February 28, 1996, Notice of Review (61 FR 7596), when we stopped
designating Category 2 species. The snuffbox is not currently listed as
a candidate species for listing.
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 74 percent of the streams it historically
occurred in. 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 65 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 33 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, and only the snuffbox persists in large
rivers with dams (Ohio River), and then only in 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.
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
[[Page 67572]]
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 two navigation pools of the Allegheny River.
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 rayed bean (Olentangy,
Salamonie, Mississinewa, Vermilion, North Fork Vermilion, Embarras
Rivers) and snuffbox (Grand, Kankakee, Sangamon, Kaskaskia, Olentangy,
Salamonie, Mississinewa, Eel, Vermilion, and North Fork Vermilion,
Embarras, Paint Rock, and St. Francis Rivers; and Tonawanda, Killbuck,
Chickamauga, and Bear Creeks) streams 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 of sodium
dimethyl dithiocarbamate, a chemical used to reduce and precipitate
hexachrome, starting in 1999 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.
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, high level of toxicity, and because the highest
concentrations
[[Page 67573]]
typically occur in mussel microhabitats (Augspurger et al. 2003, p.
2574). In addition, studies 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
established ammonia water quality criteria (EPA 1985, p. 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 recent 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
believe 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/waters10/attains_nation_
cy.control?p_report_type=T, 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
life span 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 pesticide 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), 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 L. siliquoidea glochidia were the most
sensitive organism tested to date (Bringolf et al. 2007a, p. 2094).
Roundup, 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 L. siliquoidea 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 non-permitted sites throughout the country. Permitted
discharge sites are
[[Page 67574]]
ubiquitous in watersheds with rayed bean and snuffbox populations,
providing ample opportunities for contaminants to impact the species
(for 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 has 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 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 is resulting in
``blackwater'' events (Jones and Neves 2004, p. 2). Anecdotal evidence
suggests that coal fines 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, coal mining activities occur only in the Elk River in
West Virginia (Douglas 2010, pers. comm.). However, if coal mining
activities are reinitiated in western Pennsylvania, they could 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 (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, 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.
Siltation--Excessive sedimentation affects an estimated 46 percent
of all U.S. streams (Judy et al. 1984), 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, pp. 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 from 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).
[[Page 67575]]
Interstitial spaces in the substrate provide essential habitat for
juvenile mussels. When 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 run-off) 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 run-off, 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, 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 lots, building construction,
general infrastructure (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 limits
mussel communities, reduces abundance (particularly for juveniles), and
increasingly dislodges mussels and moves them downstream (Layzer and
Madison 1995, p. 337; Myers-Kinzie et al. 2002, p. 822; Gangloff and
Feminella 2006, 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 2007, p. 88;
Butler 2002, p. 25).
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. U.S. 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.
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 is a threat to the rayed bean and snuffbox throughout all of
their range. Based on our analysis of the best available information,
we have no reason to believe that the present or threatened
destruction, modification, or curtailment of rayed bean or snuffbox
habitat will 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.
[[Page 67576]]
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 their 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 has 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 this analysis, we find that overutilization for
commercial, recreational, scientific, or educational purposes is not
now 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). 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). Generally, parasites are not
suspected of being a major limiting factor (Oesch 1984, p. 16), but a
recent study provides contrary evidence. Reproductive output and
physiological condition were negatively correlated with mite and
trematode abundance, respectively (Gangloff and Feminella 2004).
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, being nearly four
times more abundant than in quantitative surveys (Tyrrell and Hornbach
1998, p. 304). 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.
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). 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 a negative impact on mussel populations. However,
based on our analysis of the best available information, we do not
believe that disease or predation is a significant threat to the
overall status of rayed bean or snuffbox, nor do we believe that it is
likely to become a significant threat 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.
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 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 information, we have no
reason to believe that the aforementioned regulations, which currently
do not offer adequate protection to the rayed bean and snuffbox, will
be improved in the foreseeable future.
[[Page 67577]]
E. Other Natural or Manmade Factors Affecting Its 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).
Isolated populations eventually die out when population size drops
below the EPS or threshold level of sustainability. 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. 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. They may also reduce food
concentrations to levels too low to support reproduction, or even
survival in extreme cases.
Another way zebra mussels may impact native mussels is through
filtering their 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). Additionally, an indirect impact is the proliferation of
aquatic plants from increased water clarity in lakes, which in turn has
prompted managers to increase the use of herbicides that may threaten
mussels via food reduction (Marangelo 2005b, pers. comm.).
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. 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). Significant but highly fluctuating zebra mussel populations remain
largely restricted to navigational waterways, although smaller streams
have also had their mussel fauna virtually eliminated by them (Martel
et al. 2001, p. 2188). 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
[[Page 67578]]
(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), preying 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.
Additional exotic species will invariably become established 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). 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 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, p. 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.
The majority of the remaining populations of the rayed bean and
snuffbox are generally small and geographically isolated (Butler 2002,
2007). 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).
Proposed 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
scope 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. Therefore, on the basis of the
best available scientific and commercial information, we propose
listing the rayed bean and snuffbox as endangered 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 range. Therefore, we assessed the
status of the species throughout their entire range. 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 proposed determination applies to the
species throughout their entire range.
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.
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 determine 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
[[Page 67579]]
final recovery plan will be available on our Web site (http://
www.fws.gov/endangered), or from our Ohio 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.
If this 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.
Although the rayed bean and snuffbox are only proposed for listing
under the Act at this time, 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; if you submit information after the date listed in
the DATES section above, you will need to send it to the street address
provided in the FOR FURTHER INFORMATION CONTACT 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 a species or to destroy or adversely modify
its critical habitat. If a Federal action may affect a listed species
or its critical habitat, the responsible Federal agency must enter into
formal consultation with 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 proposed 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. If we finalize listing of the rayed bean and snuffbox, these
prohibitions would be 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.
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 proposed listing on proposed and
ongoing activities within a species' range. We believe, based on the
best available information, that the following actions will not result
in a violation of the provisions of section 9 of the Act, provided
these actions are carried out in accordance with existing regulations
and permit requirements:
(1) Activities authorized, funded, or carried out by Federal
agencies (e.g., bridge and highway construction, pipeline construction,
hydropower licensing, etc.), 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
[[Page 67580]]
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 believe 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 Ohio Ecological Services Field Office (see
FOR FURTHER INFORMATION CONTACT 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, Henry Whipple Federal Building, 1 Federal
Drive, Fort Snelling, MN 55111 (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, 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 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
[[Page 67581]]
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, since
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.
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' occurrences
observed in recent years indicates that current conditions are not
sufficient to meet the basic biological requirements of these species
in many rivers. Since 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, which limit 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
[[Page 67582]]
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.
Peer Review
In accordance with our policy, ``Notice of Interagency Cooperative
Policy for Peer Review in Endangered Species Act Activities,'' that was
published on July 1, 1994 (59 FR 34270), we will seek the expert
opinion of at least three appropriate independent specialists regarding
this proposed rule. The purpose of such review is to ensure listing
decisions are based on scientifically sound data, assumptions, and
analysis. We will send copies of this proposed rule to the peer
reviewers immediately following publication in the Federal Register. We
will invite these peer reviewers to comment, during the public comment
period, on the specific assumptions and the data that are the basis for
our conclusions regarding the proposal to list rayed bean and snuffbox
as endangered and our proposal regarding critical habitat for this
species.
We will consider all comments and information we receive during the
comment period on this proposed rule during preparation of a final
rulemaking. Accordingly, our final decision may differ from this
proposal.
Public Hearings
The Act provides for one or more public hearings on this proposal,
if requested. Requests must be received within 45 days after the date
of publication of this proposal in the Federal Register (see DATES).
Such requests must be sent to the address shown in the FOR FURTHER
INFORMATION CONTACT section. We will schedule public hearings on this
proposal, if any are requested, and announce the dates, times, and
places of those hearings, as well as how to obtain reasonable
accommodation, in the Federal Register and local newspapers at least 15
days before the hearing.
Persons needing reasonable accommodation to attend and participate
in a public hearing should contact the Ohio Ecological Services Field
Office at 614-416-8993, ext. 22, as soon as possible. To allow
sufficient time to process requests, please call no later than one week
before the hearing date. Information regarding this proposed rule is
available in alternative formats upon request.
Required Determinations
Clarity of Rule
We are required by Executive Orders 12866 and 12988 and by the
Presidential Memorandum of June 1, 1998, to write all rules in plain
language. This means that each rule we publish must:
(a) Be logically organized;
(b) Use the active voice to address readers directly;
(c) Use clear language rather than jargon;
(d) Be divided into short sections and sentences; and
(e) Use lists and tables wherever possible.
If you feel that we have not met these requirements, send us
comments by one of the methods listed in the ADDRESSES section. To
better help us revise the rule, your comments should be as specific as
possible. For example, you should tell us the names of the sections or
paragraphs that are unclearly written, which sections or sentences are
too long, the sections where you feel lists or tables would be useful,
etc.
Paperwork Reduction Act (44 U.S.C. 3501, et seq.)
This proposed 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 proposed rule is
available on the Internet at http://www.regulations.gov or upon request
from the Field Supervisor, Ohio Ecological Services Field Office (see
FOR FURTHER INFORMATION CONTACT section).
Author
The primary author of this proposed rule is Angela Boyer of the
Ohio Ecological Services Field Office (see FOR FURTHER INFORMATION
CONTACT section).
List of Subjects in 50 CFR Part 17
Endangered and threatened species, Exports, Imports, Reporting and
recordkeeping requirements, Transportation.
Proposed Regulation Promulgation
Accordingly, we propose to amend part 17, subchapter B of chapter
I, title 50 of the Code of Federal Regulations, as follows:
PART 17--[AMENDED]
1. The authority citation for part 17 continues to read as follows:
Authority: 16 U.S.C. 1361-1407; 16 U.S.C. 1531-1544; 16 U.S.C.
4201-4245; Pub. L. 99-625, 100 Stat. 3500; unless otherwise noted.
2. Amend Sec. 17.11(h) 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.
* * * * *
--------------------------------------------------------------------------------------------------------------------------------------------------------
Species Vertebrate
------------------------------------------------------------ population
where Critical Special
Historic range endangered Status When listed habitat rules
Common name Scientific name or
threatened
--------------------------------------------------------------------------------------------------------------------------------------------------------
* * * * * * *
[[Page 67583]]
Clams
* * * * * * *
Mussel, rayed bean................. Villosa fabalis....... U.S.A. (IL, IN, KY, NA E ........... NA NA
MI, NY, OH, PA, TN,
VA, WV, WI).
* * * * * * *
Mussel, snuffbox................... Epioblasma triquetra.. U.S.A. (AL, AR, IL, NA E ........... NA NA
IN, IA, KS, KY, MI,
MN, MS, MO, NY, OH,
PA, TN, VA, WV, WI).
* * * * * * *
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* * * * *
Dated: October 15, 2010.
Gary D. Frazer,
Acting Director, U.S. Fish and Wildlife Service.
[FR Doc. 2010-27413 Filed 11-1-10; 8:45 am]
BILLING CODE 4310-55-P