(DRAFT) - Taxonomy
Species PIGTOE, SHINY
Species Id ESIS404001
Date 13 MAR 96
TAXONOMY
NAME - PIGTOE, SHINY
OTHER COMMON NAMES - PIGTOE, SHINY; MUSSEL, PIGTOE, SHINY; MUSSEL, PEARLY, PIGTOE and SHINY
ELEMENT CODE -
CATEGORY - Aquatic Molluscs
PHYLUM AND SUBPHYLUM - MOLLUSCA,
CLASS AND SUBCLASS - BIVALVIA,
ORDER AND SUBORDER - UNIONOIDEA,
FAMILY AND SUBFAMILY - UNIONIDAE,
GENUS AND SUBGENUS - FUSCONAIA,
SPECIES AND SSP - EDGARIANA,
SCIENTIFIC NAME - FUSCONAIA EDGARIANA
AUTHORITY -
TAXONOMY REFERENCES -
COMMENTS ON TAXONOMY -
Shiny Pigtoe
Fusconaia edgariana (Lea, 1840)
KINGDOM: Animal GROUP: Clam
PHYLUM: Mollusca CLASS: Bivalvia
ORDER: Unionoidea FAMILY: Unionidae
The shiny pigtoe is a medium-sized species distinguished by very
smooth and shiny periostracum with prominent dark green to blackish
rays on a yellow to brown background. Young rays generally have bold
ray patterns whereas older specimens are dull brown with indistinct
rays. Valves are subtriangular, with surfaces marked by concentric
growth checks and a median sulcus. Beaks are turned forward and
anterior to the midline with rather deep beak cavities. The left
valve contains 2 irregular pseudocardinal and 2 nearly straight
lateral teeth, whereas the right valve has 3 pseudocardinals and 1
lateral tooth (occasional vestigial tooth ventrad). The pallial line
is well defined anteriorly and nacre color is white. Valves of male
and female specimens exhibit no known sexual dimorphism (01).
The taxonomic history of this species is complicated (02) and
will not be discussed in detail here. The species was described as
Unio cor by Conrad in 1834 from the Elk and Flint Rivers in Alabama,
Taxonomy - 1 (DRAFT) - Taxonomy
Species PIGTOE, SHINY
Species Id ESIS404001
Date 13 MAR 96
and as Fusconaia (Unio) edgarianus by Lea in 1840 (03 and 04 as cited
in 01). A compressed headwater form (Fusconaia edgariana analoga) was
described by Ortmann (1918) (05). Fusconaia cor (Conrad 1834) is
indicated as a synonym by Ahlstedt (Unpubl. report) (06), and Weber et
al. (1981) (07). F. edgariana is closely related to F. cuneolus,
differing primarily in characteristics of the epidermis (14). Bogan
and Parmalee (08) provide a list of the synonymy for the shiny pigtoe
as follows:
Unio edgarianus Lea, 1840;
Margaron (Unio) edgarianus (Lea);
Pleurobema edgarianus (Lea);
Fusconaia edgariana (Lea);
Fusconaia edgariana analoga Ortmann, 1918;
Quadrula analogia (Ortmann);
Unio obuncus Lea, 1871;
Unio andersonensis Lea, 1972;
Unio cor Conrad, 1834;
Margaron (Unio) cor (Conrad);
Pleurobema cor (Conrad);
Quadrula cor (Conrad);
Quadrula (Pleuronaia) cor (Conrad); and
Fusconaia cor (Conrad).
Other common names for this species include shiny pigtoe mussel
and shiny pigtoe pearly mussel.
Photographs/slides useful in identifying the species are on file
at the following Fish and Wildlife Service field offices:
U.S. Fish and Wildlife Service & U.S. Fish and Wildlife Service
Annapolis Field Office Asheville Field Office
1825-B Virginia St. 100 Otis St.
Annapolis, MD 21401 Ashville, NC 28801.
Taxonomy - 2 (DRAFT) - Status
Species PIGTOE, SHINY
Species Id ESIS404001
Date 13 MAR 96
STATUS
Coded Status
Alabama; Federal Endangered
Alabama; Unofficially Listed
Tennessee; Federal Endangered
Tennessee; State Listed
Virginia; Federal Endangered
Virginia; State Recognized
Virginia; Unofficially Listed
E: Federal Endangered
Commercial
COMMENTS ON STATUS -
U.S. STATUSES AND LAWS:
The shiny pigtoe (Fusconaia edgariana) is listed as Endangered
pursuant to the Endangered Species Act of 1973, as amended (50 CFR
17.11). This designated status applies wherever found.
This species is protected by the Lacey Act (P.L. 97-79, as
amended; 16 U.S.C. 3371 et seq.) which makes it unlawful to import,
export, transport, sell, receive, acquire, or purchase any wild animal
(alive or dead including parts, products, eggs, or offspring):
(1) in interstate or foreign commerce if taken, possessed,
transported or sold in violation of any State law or
regulation; or
(2) if taken or possessed in violation of any U.S. law,
treaty, or regulation or in violation of Indian tribal law.
It is also unlawful to possess any wild animal (alive or dead
including parts, products, eggs, and offspring) within the U.S.
territorial or special maritime jurisdiction (as defined in
18 U.S.C. 7) that is taken, possessed, transported, or sold in
violation of any State law or regulation, foreign law, or Indian
tribal law.
RESPONSIBLE FEDERAL AGENCIES:
USFWS -Responsible for the management/recovery, listing, and
law enforcement/protection of this species.
USFS -Responsible for the law enforcement/protection of the
species with applicable State and Federal laws on
public lands under their control. Also responsible
for management/recovery on Forest Service lands. The
management, protection, and conservation of federally
listed species into the Forest Planning process
(36 CFR 219.19 and 219.20). Management practices that
would cause detrimental changes in water temperature
or composition, water course blockage, or sediment
deposits within 100 feet of the edges of perennial
streams, lakes or other bodies of water are prohibited
(36 CFR 219.27(e)).
Status - 1 (DRAFT) - Status
Species PIGTOE, SHINY
Species Id ESIS404001
Date 13 MAR 96
Status - 2 (DRAFT) - Status
Species PIGTOE, SHINY
Species Id ESIS404001
Date 13 MAR 96
All Federal agencies have responsibility to ensure that any
action authorized, funded, or carried out by that agency is not likely
to jeopardize the continued existence of the species or result in the
destruction or adverse modification of Critical Habitat (50 CFR 402),
and to utilize their authorities to carry out programs for the
conservation of the species.
STATE STATUSES AND LAWS:
STATE: Alabama
UNOFFICIAL LIST: Endangered, IN: Endangered and threatened
plants and animals of Alabama. Alabama Museum
of Natural History, Bulletin No. 2. (The shiny
pigtoe is listed under the synonym Fusconaia
cor.)
STATE: Virginia
DESIGNATED STATUS: Recognized Endangered
ADMINISTRATIVE AGENCY: VA Commission of Game and Inland
Fisheries.
STATE STATUTES: State Code 29.231 to 29.237
UNOFFICIAL LIST: Endangered, IN: Proceedings of the Symposium
on Endangered and Threatened Plants and Animals
of Virginia. Held May 19-20, 1978, VPI&SU,
Blacksburg, VA.
STATE: Tennessee
DESIGNATED STATUS: Endangered
ADMINISTRATIVE AGENCY: TN Wildlife Resources Agency.
STATE STATUTES: TN Code Ann., Chapter 9, Sec. 51-901 through
51-912, and Proclamations 75-15, 76-4 and
amendments.
INTERNATIONAL STATUSES, TREATIES, AND AGREEMENTS:
This species is listed in Appendix I of CITES as endangered.
ECONOMIC STATUSES:
Historically, freshwater mussels like the shiny pigtoe were
commercially valuable as a source of material for buttons. This
species' sedentary nature and filter feeding habits may make it useful
as a water quality indicator. It has been shown that mussels
accumulate such pollutants as heavy metals and pesticides.
74/10/17:39 FR 37078/37079 - Notice of review
75/09/26:40 FR 44329/44333 - Proposed rule, list as Endangered
76/06/14:41 FR 24062/24067 - Final rule, listed as Endangered
76/06/16:41 FR 24367/24378 - Proposed rule, CITES I
77/02/22:42 FR 10484/10485 - Final rule, CITES I
81/02/27:46 FR 14652/14658 - Five year review
87/07/07:52 FR 25523/25528 - Five year review
87/07/07:52 FR 25523/25528 - Notice of Review
Status - 3 (DRAFT) - Status
Species PIGTOE, SHINY
Species Id ESIS404001
Date 13 MAR 96
Status - 4 HABITAT ASSOCIATIONS
HABITAT - AQUATIC
INLAND AQUATIC
SOCIETY OF AMERICAN FORESTRY TYPES
SAF TYPE STAGE CLOSURE
Shortleaf Pine-Oak shrub--seedling
Shortleaf Pine-Oak young tree
Shortleaf Pine-Oak mature tree
Shortleaf Pine-Oak Old Growth
shrub--seedling
young tree
mature tree
Old Growth
LAND USE -
Industrial
Transportation, communications, and Util
Cropland and Pasture
Deciduous Forest Land
Mixed Forest Land
Streams and Canals
Strip Mines, Quarries, and Gravel Pits
NATIONAL WETLAND INVENTORY CODES
NWI NWICLS NWIMOD NWISPEC
Riverine, upper perennial UB2
Riverine, upper perennial UB1
Riverine, upper perennial SB1
Riverine, upper perennial BB1
COMMENTS ON HABITAT ASSOCIATIONS -
The shiny pigtoe is typically a riffle species, found along
riffles, fords, and shoals of clear, moderate to fast-flowing streams
and rivers with a stable substrate (08). It does not inhabit deep
pools, impounded waters, or other lentic habitats (01). The species
is usually observed well buried in the sand and gravel substrate
during most of the year, and is more readily visible in early summer
(15,16,17).
Although this species occurs only in riverine habitats, it can be
affected (through run-off) by land uses and treatments on surrounding
areas and is therefore "associated" with other habitats within the
upper Tennessee River basin. In Virginia, rivers inhabited by the
shiny pigtoe flow through oak-hickory and oak-pine forests (13).
Major agricultural areas in southwest Virginia include pasturelands,
hay and corn, with some areas of burly tobacco (18). Effluents from
industrial, municipal and mining operations are discharged into rivers
inhabited by the species (01,14), and silt input from bridge
construction has been observed by Neves et al. (14).
Ellis (1936) demonstrated that mussels could not survive in
substrate on which silt (0.6-2.5 cm) was allowed to accumulate; death
was attributed to interference with feeding and suffocation (01,10).
However, the shiny pigtoe appears to be able to tolerate small amounts
of silt over the substrate (2 mm or less) but requires ample water
flow and a stable, sand or gravel substrate (01,15,16).
Neves et al. (1980) collected large amounts of data on water
Habitat Associations - 1 quality, flow rates, dissolved solids, pH, dissolved oxygen, etc.,
from rivers inhabited by endangered mussels in VA (14). Hydrologic
data demonstrated that the streams of the upper TN River basin are
subject to extreme and rapid fluctuations in flow to which the mussel
fauna is exposed and apparently adapted (14). Within a single year,
maximum flows may exceed minimum flows by nearly 400 times in the
Clinch River and 500 times in the Powell River (14). Dissolved oxygen
measurements at sites inhabited by the shiny pigtoe ranged from 5.5
mg/l to 16 mg/l in the Clinch River, 6 to 17.8 mg/l in the Powell
River, and 6 to 19 mg/l in the North Fork Holston River, between
January 1975 and June 1980 (14). Measurements of pH during the same
period and at the same sites ranged from 6.8 to 9.2 in the Clinch, 7.5
to 9.0 in the Powell, and 7.0 to 9.1 in the North Fork Holston River
(14). Numerous other characteristics of these rivers were also
measured. It is important to note, however, that this information
from sites inhabited by the shiny pigtoe helps define only what is
(apparently) tolerated by the species. Without historical data on
concurrent riverine conditions and mussel distribution to compare with
that at the present, one cannot define the limiting factors, or
specific environmental parameters required by the species.
Habitat of the glochidia (embryonic life stage) is within the
gills of the female, then in the water column, and finally attached to
a suitable fish host (30). Any alteration of these life
stage-specific habitats during its life cycle would likely affect the
long-term success of a population (01). Habitat requirements or
associations for the juvenile stage are unknown.
Habitat Associations - 2 (DRAFT) - Food Habits
Species PIGTOE, SHINY
Species Id ESIS404001
Date 13 MAR 96
FOOD HABITS
TROPHIC LEVEL -
OMNIVORE
LIFESTAGE FOOD FOOD PART
General Detritus
General Bacteria
General Phytoplankton
General Diatoms
General Algae
General Zooplankton
General Fish
Food Habits - 1 (DRAFT) - Environment Associations
Species PIGTOE, SHINY
Species Id ESIS404001
Date 13 MAR 96
ENVIRONMENTAL ASSOCIATIONS
G = General A = Adult
LIM = Limiting RA = Resting Adult
J = Juvenile FA = Feeding Adult
RJ = Resting Juvenile BA = Breeding Adult
FJ = Feeding Juvenile P = Pupae
L = Larvae E = Egg
RL = Resting Larvae
FL = Feeding Larvae
LIFESTAGE ENVIRONMENTAL ASSOCIATIONS
G Aquatic Features: Pool areas
Environment Associations - 1 (DRAFT) - Life History
Species PIGTOE, SHINY
Species Id ESIS404001
Date 13 MAR 96
LIFE HISTORY
FOOD HABITS:
There are no known interspecific differences in feeding amony
adult freshwater mussels (22). The glochidia are obligate parasites
on the gills or fins of fish (01).
Adult shiny pigtoes, like other freshwater mussels, are filter
feeders (15,16). Water is drawn into the mussel through the inhalant
siphon and passed over specialized gills which filter out suspended
food particles (16). Food material commonly found in the intestinal
tract includes desmids, diatoms, filamentous algae, detritus, bacteria
and plankton (02,16,19,20). It is not known, however, which of these
items are used as nutritional sources, or if some are passed through
the gut intact (19).
Mature glochidia, or larvae, are released by the female during
the spring and summer (01). These glochidia attach to the fins or
gills of certain host fish to encyst and metamorphose to the juvenile
stage (01). During this period the glochidia are sustained by the
tissues of their hosts (16).
HOME RANGE/TERRITORY:
The shiny pigtoe is non-territorial and the concept of home
range/territory does not apply to this species. Fusconaia edgariana
is sedentary during its adult life and generally occurs in sections of
river with others of its kind (17).
PERIODICITY:
Irregular or unpredictable factors, such as turbidity, probably
regulate daily and short-term activity of the species (02). The
pigtoe does exhibit seasonal periodicity in terms of vertical movement
within the substrate. During most of the year, the species is
well-buried in the substrate; when mature glochidia are released
during June or July, the species is found much closer to the surface
(02,17).
MIGRATION PATTERNS:
This is a sedentary, non-migratory species.
COVER/SHELTER REQUIREMENTS:
The shiny pigtoe is typically a riffle species, found along
riffles, fords, and shoals of clear, moderate to fast flowing rivers
with a stable substrate of gravel, mixed sand, pebble, and cobble (01,
08,15,16). A minimum depth of 5 or 6 inches of coarse substrate is
probably required, based on observations of well-buried mussels (02).
Water depths are commonly shallow (15-30 cm or less) in riffles where
mussels are common (12).
REPRODUCTIVE SITE REQUIREMENTS:
For sedentary mussels like the pigtoe, reproductive site
requirements are the same as cover/shelter requirements.
REPRODUCTIVE CHARACTERISTICS:
The shiny pigtoe is a short-term breeder (31). During the
Life History - 1 (DRAFT) - Life History
Species PIGTOE, SHINY
Species Id ESIS404001
Date 13 MAR 96
spawning period in late spring, male pigtoes release sperm into the
water column and the sperm are taken in by the females during
syphoning (01,16). Females are "receptive" during 3 or 4 weeks in
May, and ovulation may be triggered by the detection of sperm in the
water column (02). Eggs are fertilized in the suprabranchial cavity
or gills, which also serve as marsupia for larval development into
mature glochidia (01). Based on studies of similar short-term
breeders (Quadrula sp.), fertilized eggs develop into mature glochidia
in about 3 to 4 weeks, depending on water temperature (02). Each
gravid female releases up to several hundred thousand mature glochidia
in June or early July (01,02,17). Embryos (glochidia) are released
into the water column as conglutinal masses, the size, shape and color
of which are unique to the species. Glochidia will die in a matter of
days if they fail to attach to the gills or fins of certain host fish
where they encyst and metamorphose to the juvenile stage (01,02,15).
Fully developed juvenile pigtoes drop to the stream bottom about 3 to
5 weeks (depending on water temperature), after infecting the host
fish (02). Juvenile mussels reach sexual maturity in about 4 years
(02).
Female shiny pigtoes have been found gravid (marsupial gill
chambers filled with glochidia) in May (31), June and July (17) and
ranged in age from 6 to 20 years (17). Conglutinates are
subcylindrical in shape, range from pink to red in color (31,17) and
contain approximately 350 - 400 eggs and/or developing glochidia (17).
Glochidia are horseshoe shaped and hookless, and shell length averages
143 microns. Females release glochidia from June to August, with peak
release periods in July. Females from the North Fork Holston River
near Saltville, VA, released conglutinates containing few developing
glochidia and numerous unfertilized eggs (17).
Fish of the family Cyprinidae have been found to be host fish.
Species found naturally encysted with shiny pigtoe glochidia in the
North Fork Holston River were Notropis galacturus (whitetail shiner),
N. cornutus (common shiner), N. coccigenus (warpaint shiner), and N.
telescopus (telescope shiner). Labaroratory induced infections
indicate the whitetail and common shiners are probably host species
(01,17).
PARENTAL CARE:
Glochidia are retained within the gills of the female prior to
release (30). No other parental care occurs.
POPULATION BIOLOGY:
The most severe limiting factor to the species continues to be
habitat degradation, primarily from siltation due to poor mining
practices and other land uses (15,16). Predation, especially from
muskrats, may also be a significant limiting factor (02). At a site
on the North Fork Holston River, Neves observed the loss of 25% of the
mussel population to predation by muskrats - during only a 2 year
period (02). Periodic disease outbreaks and natural die-offs may also
occur (02). Accidental industrial chemical spills remain a potential
limiting factor (16).
The shiny pigtoe is found in association with diverse mussel
assemblages, in low densities (1 to 5 individuals per 2 sq m) relative
Life History - 2 (DRAFT) - Life History
Species PIGTOE, SHINY
Species Id ESIS404001
Date 13 MAR 96
Life History - 3 (DRAFT) - Life History
Species PIGTOE, SHINY
Species Id ESIS404001
Date 13 MAR 96
to densities of other species (14).
Freshwater mussels are long lived, many reaching ages of 20 to 50
years (15). Shiny pigtoes are known to live as long as 25 years (02).
Shiny pigtoes from the North Fork Holston River ranged from 12.8 mm in
length (3 years) to 59.8 mm in length (20+ years). Individuals aged
between 7 to 20 years dominated the majority of the population, with
very few specimens less than 6 years of age. The sex ratio,
determined by comparing gravid females to non-gravid individuals,
appears to be 1:1 in the North Fork Holston River (17). Sex ratios of
sexually dimorphic freshwater mussel species approximate 1:1 (02).
Survival and mortality rates are not known.
The shiny pigtoe has a good potential for recovery if habitat
containing F. edgariana is protected and enhanced, and populations are
established or expanded in rivers and river corridors which
historically contained the species (01). Population will be
considered recovered when reproducing populations occur in: 1) the
North Fork Holston River above Saltville, Smyth Co., VA; 2) the Clinch
River from backwaters of Norris Reservoir, TN upstream to Nash Ford
(CRM 280), Russell Co., VA; 3) the Powell River from the backwaters of
Norris Reservoir, TN upstream to Flanary Bridge (PRM 130) Lee Co., VA;
4) the Elk River in Lincoln Co., TN; 5) the Paint Rock River in
Jackson Co., AL; and 6) Copper Creek in Scott Co., VA. In addition,
re-establishment and/or discoveries of new populations must result in
viable populations in one additional river or two additional river
corridors which historically contained the species (01).
SPECIES INTERRELATIONSHIPS:
The shiny pigtoe is dependent on one or more fish species during
the larval stage of its life cycle (02,15,16). Glochidia attach to
the gills or fins of these fish, where they encyst, feed off the
fish's tissues and metamophose into juvenile mussels (01,15,16).
Kitchel (1983) found the gill lamellae of several cyprinid species
infected with shiny pigtoe glochidia in the North Fork Holston River
(01,17). These species included Notropis galacturus (whitetail
shiner), N. cornutus (common shiner), N. coccogenis (warpaint shiner),
and N. telescopus (telescope shiner) (01,17). Based on
laboratory-induced infections, the common shiner and the whitetail
shiner were tentatively identified as fish hosts for the shiny pigtoe
(01,17).
Freshwater mussels serve as food for muskrats and raccoons (32).
Predation begins in late fall, after frost eliminates available
vegetation, and occurs near shore. Moderate to small shells are pried
open and found in piles (middens) in the stream or on the riverbank
(33). A study of muskrat predation on the shiny pigtoe in the North
Fork Holston River, VA, indicated that adult shells comprised 12% of
the middens (21). Muskrats consumed roughly 26% of the shiny pigtoe
population at North Holston Ford, North Fork Holston River (21).
OTHER LIFE HISTORY DESCRIPTORS:
Because juvenile mussels are rarely observed evenly interspersed
through an adult mussel bed, it is believed that they may have
different microhabitat requirements (02). Studies investigating this
possibility are currently underway at Virginia Tech (02).
Life History - 4 (DRAFT) - Life History
Species PIGTOE, SHINY
Species Id ESIS404001
Date 13 MAR 96
Life History - 5 (DRAFT) - Management Practices
Species PIGTOE, SHINY
Species Id ESIS404001
Date 13 MAR 96
MANAGEMENT PRACTICES
RESULT MANAGEMENT PRACTICE
Beneficial Developing/maintaining stream structures
Beneficial Maintaining/Controlling Water Flow
Beneficial Controlling/Restricting Mining
Beneficial Controlling/Restricting Road Maintainance Actions
Beneficial Maintaining undisturbed/undeveloped areas
Beneficial Land Acquisition
Beneficial Controlling pollution [thermal, chemical, physical]
Beneficial Controlling/Restricting Pesticide Use
Beneficial Controlling/Restricting Herbicide Use
Beneficial Controlling/Restricting Agricultural Practice
Beneficial Stocking captive-reared wild-strain animals
Beneficial Transplanting wild animals
Beneficial Transplanting Wild Eggs/Wild Seeds
Beneficial Restricting Poaching
Beneficial Controlling/Restricting Noncommercial Harvest
Adverse Collecting
Existing Collecting
Adverse Commercial Exploitation
Existing Commercial Exploitation
Adverse Off Road Vehicles
Existing Off Road Vehicles
Adverse Inherent Reproductive Characteristics
Existing Inherent Reproductive Characteristics
Adverse Surface Mines
Existing Surface Mines
Adverse Rural Residential/Industrial Areas
Existing Rural Residential/Industrial Areas
Adverse Soil compaction by heavy equipment in mine areas
Existing Soil compaction by heavy equipment in mine areas
Adverse Siltation
Existing Siltation
Adverse Water Temperature Alteration
Existing Water Temperature Alteration
Adverse Dissolved Oxygen Reduction
Existing Dissolved Oxygen Reduction
Adverse Water Level Stabilization
Existing Water Level Stabilization
Adverse Water Level Fluctuation
Existing Water Level Fluctuation
Adverse Irrigating
Existing Irrigating
Adverse Reservoirs
Existing Reservoirs
Adverse Migration barriers
Existing Migration barriers
Adverse Dredging
Existing Dredging
Adverse Applying fertilizers
Existing Applying fertilizers
Management Practices - 1 (DRAFT) - Management Practices
Species PIGTOE, SHINY
Species Id ESIS404001
Date 13 MAR 96
RESULT MANAGEMENT PRACTICE
Adverse Applying herbicides
Existing Applying herbicides
Adverse Applying pesticides
Existing Applying pesticides
Adverse Environmental Contamination/Pollution
Existing Environmental Contamination/Pollution
Adverse Exotic/Feral/Introducted Species
Existing Exotic/Feral/Introducted Species
Adverse Erosion
Existing Erosion
Adverse
Existing
Adverse Harvesting
Existing Harvesting
COMMENTS ON MANAGEMENT PRACTICES -
The mussel fauna in many streams of the upper Tennessee River
drainage have been impacted by dam construction, channelization,
siltation, and water pollution, which directly affect all mussel
species (01,22). This change from lotic to lentic habitat has also
altered the species composition of the fish community, thus
jeopardizing the reproductive success of some mussel species by
removing required fish hosts (01).
Dam construction and impoundments in the Tennessee River and its
tributaries has probably been the most significant factor contributing
to the decline of the shiny pigtoe and other Cumberlandian species. A
total of 51 impoundments on the Tennessee and Cumberland Rivers have
eliminated large sections of riverine habitat within the historic
range of the shiny pigtoe (01). The shiny pigtoe is typically a
riffle species, found along fords and shoals of clear, moderate to
fast-flowing streams and rivers with a stable substrate (08 as cited
in 01). It is quite sedentary, susceptible to stream degradation, and
does not inhabit deep pools or impoundments. Although siltation has
been suggested as the most significant adverse affect of impoundments
on mussels (22,09), other detrimental factors have included lowered
water temperature, pH changes, oxygen depletion in the hypolimnion,
and dewatering of mussel beds below dams (22). Hypolimnial discharges
from reservoirs produce cold tailwater conditions which alter typical
fish and benthic assemblages. Fuller stressed that these changes
adversely affected both juvenile and adult mussels, and may further
jeopardize the reproductive potential of the mussels by altering the
native fish species, eliminating possible fish hosts essential for
glochidial metamorphosis (01).
Silt derived from erosion in the Tennessee Valley originates from
poorly implemented land use practices associated with strip-mining,
road construction, forestry and agricultural operations (including the
use of associated heavy equipment). Ellis (10) found that mussels
could not survive in substrate on which silt (0.6-2.5 cm) was allowed
to accumulate; death resulted from interference with feeding and
suffocation (10). Ellis also found that erosional silt reduces light
Management Practices - 2 (DRAFT) - Management Practices
Species PIGTOE, SHINY
Species Id ESIS404001
Date 13 MAR 96
penetration, alters heat exchange in the water, and allows organic and
toxic substances to be carried to the bottom where they remain for a
long time and affect benthic organisms (10). This physical process
leads to oxygen depletion and the possible absorption of toxicants by
mussels (11). Erosional silt is now a common element of the impounded
Tennessee River, much of it originating from surrounding agricultural
land (23,24,25).
Coal mining wastes, including coal washings, also contribute to
the sediment load in the Tennessee River and its tributaries,
especially the upper Powell River and tributary streams of the Clinch
(01). Coal wastes react chemically with water to reduce pH. Kitchel
et al. (12) observed in laboratory experiments, with coal fines in
suspension and coal waste in the substrate, that coal fines apparently
interfere with normal feeding processes and may produce chronic
effects (12). Negative impacts on mussels from coal mining, coal
washing, and fly ash waste have been identified as major problems to
mussel recovery in the Clinch River (22).
Water pollution (heavy metal and chemical pollution) is another
major factor that has contributed to the endangered status of the
shiny pigtoe. Nitrogen and phosphorus from agricultural run-off
organically enrich streams and affect both mussel and their fish
hosts. The shiny pigtoe was eradicated from the North Fork Holston
River below Saltville by sodium, chloride and mercury released by a
now defunct chemical plant at Saltville, VA (14). These wastes
contaminated the river for more than 80 river miles (128 km) below
Saltville and the shiny pigtoe now occurs only upstream of Saltville,
VA, in this river (01). The Holston River above Cherokee Reservoir in
TN receives discharges from major industrial and municipal sources.
The distribution of the shiny pigtoe in the Clinch River was severely
reduced by 2 chemical spills (in 1967 and 1970) at a power plant in
Carbo, VA. The fauna was eliminated for roughly 18 river miles
(28 km) below Carbo in 1967 due to the accidental release of 198
million cubic meters of fly ash slurry (pH 12) and 11 river miles
(18 km) in 1970 due to a sulfuric acid spill (01,26,14). Recent
biological surveys indicate that the mussel fauna has not recovered
from these spills (28,29,14). The siphoning period and metabolic rate
of mussels can also be affected by such comtaminants as heavy metals
and agricultural chemicals (27).
In the late 1800s, mussel shells were widely used in
manufacturing buttons for the clothing industry, and commercial
harvesting led to the decline of many species (15). Currently,
unknowing but illegal collection of endangered mussels occurs in
several southeastern states (14).
Habitat destruction by channelization, sand and gravel
acquisition from fords and shoals, and vehicle crossings over
streambeds has been observed in Virginia by Neves et al. (14).
The invasion of the Asiatic clam (Corbicula fluminea) into
Eastern rivers has been implicated as a competitor of freshwater
mussels (23). This exotic clam is now widespread in the Tennessee
River drainage and may be affecting populations of the shiny pigtoe.
No species specific data exists to document the deleterious effects of
the Asiatic clam or the previously mentioned environmental
disturbances on Fusconaia edgariara. It can only be assumed that
Management Practices - 3 (DRAFT) - Management Practices
Species PIGTOE, SHINY
Species Id ESIS404001
Date 13 MAR 96
most, if not all, mussels respond similarly to the same environmental
perturbations.
APPROVED PLAN:
U.S. Fish and Wildlife Service. 1984. Shiny Pigtoe Pearly Mussel
(Fusconaia edgariana) Recovery Plan. U.S. Fish and Wildlife Service,
Atlanta, GA. 67 pp.
The recovery of the shiny pigtoe can be achieved by protecting
and enhancing habitat containing the species, and by establishing or
expanding populations within rivers and river corridors which
historically contained the species. Specific recovery recommendations
include:
1) Preserve populations and habitats of F. edgariana in the North
Fork Holston, Clinch, Powell, Elk and Paint Rock Rivers & in
Copper Creek.
a) Conduct population surveys and critical habitat analyses.
b) Identify current and future anthropogenic threats to the
species and take actions that will lead to their mitigation or
elimination. Known and probable threats include coal mining,
toxic spills, road and bridge construction, gravel dredging,
flood control, pesticide/herbicide use, and agricultural or
urban development runoff.
c) Solicit support from various public agencies and private groups
or individuals for the protection and recovery of the species,
and provide copies of the recovery plan to all interested
parties. Investigate the feasibility of protecting the species
through special sanctuaries, state refuges, collecting permit
restrictions, or other means. Control incidental take and
collecting for scientific or other purposes.
2) Conduct life history research on the species, to include
gametogenesis, fish host identification, age class structure,
growth rate, life tables, and mortality factors.
3) Determine feasibility of introducing the species into 1
additional river or establishing new population centers in 2
rivers where it currently resides; implement such activities
where feasible; e.g, through introduction of transplanted adults
or juveniles, artificially cultured or otherwise, or introduction
of glochidia infested fish hosts.
4) Outline and implement a schedule to monitor population levels and
trends in extant and introduced populations and population
centers.
5) Evaluate success of individual activities and overall success of
recovery program; recommend revisions or additional actions as
necessary to recover the species.
Present recovery efforts involve studies to determine the impact
Management Practices - 4 (DRAFT) - Management Practices
Species PIGTOE, SHINY
Species Id ESIS404001
Date 13 MAR 96
of chlorine, enforcement of regulations, information/education effort,
and to determine the distribution of juvenile mussels.
Management Practices - 5 (DRAFT) - References
Species PIGTOE, SHINY
Species Id ESIS404001
Date 13 MAR 96
References
***** REFERENCES FOR ALL NARRATIVES EXCEPT N-OCCURRENCE *****
01 U.S. Fish and Wildlife Service. 1984. Recovery Plan for the Shiny
Pigtoe Pearly Mussel (Fusconaia edgariana). U.S. Fish and Wildlife
Service, Atlanta, GA. 67 pp.
02 Neves, Richard J. September 22, 1983. Personal communication.
Assistant Unit Leader, VA Coop. Fisheries Res. Unit, VPI & SU,
Blacksburg, VA 24061.
03 Conrad, T.A. 1834. Description of some new species of freshwater
shells from Alabama, Tenn., etc. Am. J. Sci. Arts 35(s):338-343.
04 Lea, I. 1840. Descriptions of new freshwater and land shells.
Proc. Am. Phil. Soc., Phila. 1:284-289.
05 Ortmann, A.E. 1918. The nayades (freshwater mussels) of the upper
Tennessee drainage with notes on synonymy and distribution. Proc.
Am. Phil. Soc., Phila. 57:521-626.
06 Ahlstedt, Steven. Jan 20, 1980. Critical habitat recommendations
for the shiny pigtoe pearly mussel - Fusconaia edgariana (Lea
1840). Unpubl. report. on file at: TVA, Office Nat. Resour. East
Area Office Oper. Group, Norris, TN 37828. Prepared under USFWS
Contract No. TV50926A.
07 Weber, C.I., C.D. Silver, and P.A. Lewis. 1981. A coded master
list of aquatic organisms, 2nd ed. Aquatic Biology Section,
Biological Methods Branch, Environmental Monitoring and Support
Lab., EPA, Cincinnati, OH 45268. 162 pp.
08 Bogan, A. and P. Parmalee. 1983. Tennessee's rare wildlife. Vol.
II: The mollusks. Tenn. Wildl. Resour. Agency, Nashville, TN.
123 pp.
09 Fuller, S.L.H. 1974. Clams and mussels (Mollusca:Bivalvia).
Pages 215-273. IN: Pollution ecology of Freshwater Invertebrates.
C.W. Hart, Jr and S.L.H. Fuller, eds. Academic Press, NY.
10 Ellis, M.M. 1936. Erosion silt as a factor in aquatic
environments. Ecology 17:29-42.
11 Harman, W.N. 1974. The effects of reservoir construction and
chanalization on the mollusks of the upper Delaware watershed.
Bull. Amer. Malacol. Union 1973:12-14.
12 Kitchel, H.E., J.C. Widlak and R.J. Neves. 1981. The impact of
coal mining wastes on endangered mussel populations in the Powell
River, Lee Co., Virginia. Final report. VA Coop. Fishery Res.
Unit, VPI&SU, Blacksburg, VA. 26 pp.
13 Eyre, F.H. 1980. Forest cover types of the United States and
Canada. Soc. of American Foresters. 148 pp.
14 Neves, R.J., G.B. Pardue, E.F. Benfield and S.D. Dennis. 1980. An
evaluation of endangered mollusks in Virginia. Final report, Va.
Comm. Game and Inland Fish., Proj. No. E-F-1. Richmond, VA.
140 pp.
15 Parker, W. and L. Dixon. 1980. Endangered and threatened wildlife
of Kentucky, North Carolina, South Carolina and Tennessee. U.S.
Fish and Wildlife Service and the NC Agric. Extension Serv.
AG-185. 115 pp.
16 White, C.P. 1982. Endangered and threatened wildlife of the
Chesapeake Bay Region: Delaware, Maryland and Virginia. Tidewater
References - 1 (DRAFT) - References
Species PIGTOE, SHINY
Species Id ESIS404001
Date 13 MAR 96
Publishers, Centreville, MD. 147 pp.
17 Kitchell, H.E. 1983. The life history of Fusconaia edgariana
(Mollusca:Bivalvia) from the North Fork Holston River, Smyth Co.,
VA. M.S. Thesis, VPI&SU, Blacksburg, VA. 105 pp.
18 Moser, G.A. September 1983. Personal communication. Endangered
species specialist, U.S. Fish and Wildlife Service, 1825 Virginia
St., Annapolis, MD 21401.
19 Dennis, S.D. 1978. Characterization of freshwater mussel habitat.
Unpubl. research proposal. VPI&SU, Blacksburg, VA.
20 Allen, W.R. 1914. The food and feeding habits of freshwater
mussels. Marine Biol. Lab., Woods Hole, MA. Biol. Bull. 27(3).
21 Neves, R.J., H.E. Kitchel, J.C. Widlak. 1983. Life history of the
endangered shiny pigtoe, Fusconaia edgariana. Report to Office of
Endangered Species, U.S. Fish and Wildlife Service. Coop.
Agreement 14-16-0009-81-919. 102 pp.
22 Alhstedt, S. 1984. Twentieth century changes in the freshwater
mussel fauna of the Clinch River (Tennessee and Virginia). MS
Thesis, Univ. Tenn., Knoxville, TN. 102 pp.
23 Scruggs, G.D. 1960. Status of freshwater mussel stocks in the
Tennessee River. U.S. Fish and Wildife Service Special Rept.,
Fish. No. 37:1-44.
24 Bates, J.M. 1962. The impact of impoundment on the mussel fauna
of Kentucky Reservoir, Tennessee River. Am. Midl. Nat. 68:232-236.
25 Williams, J.C. 1969. Mussel fishery investigstion of Tennessee,
Ohio and Green Rivers. Final Rept., Kentucky Proj. No. 4-19-R.
107 pp.
26 Cairns, J., J.S. Crossman, K.L. Dickson, and E.E. Herrides. 1971.
The recovery of damaged streams. Assoc. Southeast. Biolog. Bull.
18-79-106.
27 Salanki, J. 1979. Behavioral studies in mussels under changing
environmental conditions. Symp. Biol. Hung. 19:167-176.
28 Bates, J.M. and S.D. Dennis. 1978. The mussel fauna of the Clinch
River, Tennessee and Virginia. Sterkiana 69-70:3-23.
29 Tennessee Valley Authority. Aug. and Nov. 1979. An evaluation of
mussel populations in the Clinch River, Tennessee and Virginia.
Unpubl. report available from: Division of Water Resources,
Fisheries and Aquatic Ecology Branch, Norris, TN 37828. 14 pp.
30 Stein, C. 1971. Naiad life cycles: Their significance in the
conservation of the fauna. Pages 19-25. IN: Rare and endangered
mollusks (naiads) of the U.S. S.E. Jorgensen and R.W. Sharp, eds.
Dept. of Interior, Twin Cities, MN.
31 Ortmann, A.E. 1921. The anatomy of certain mussels from the upper
Tennessee. Nautilus 34:81-91.
32 Dennis, S. 1979. Freshwater and terrestrial molluscs. Pages
123-127. IN: Endangered and threatened plants and animals of
Virginia. D.W. Linzey, ed. Center for Environ. Studies, VPI & SU,
Blacksburg, VA.
33 Evermann, B.W. and H.W. Clark. 1920. Lake Maxinkuckee, a physical
and biological survey. Ind. Conserv. Publ. No. 7. 512 pp.
***** REFERENCES FOR N-OCCURRENCE NARRATIVE ONLY *****
References - 2 (DRAFT) - References
Species PIGTOE, SHINY
Species Id ESIS404001
Date 13 MAR 96
01 U.S. Fish and Wildlife Service. 1984. Recovery Plan for the Shiny
Pigtoe Pearly Mussel (Fusconaia edgariana). U.S. Fish and Wildlife
Service. 67 pp.
02 Stansberry, D.H. 1972. The mollusk fauna of the North Fork
Holston River at Saltville, Virginia. Bull. Amer. Malacol. Union.
1971:45-46.
03 Stansberry, D.H. and W.J. Clench. 1974. The Pleuroceridae and
Unionidae of the North Fork Holston River above Saltville, VA.
Bull. Amer. Malacol. Union 1973:33-36.
04 Neves, R.J., G.B. Pardue, E.F. Benfield and S.D. Dennis. 1980. An
evaluation of endangered mollusks in Virginia. Final report. VA
Commission of Game and Inland Fisheries Project No. E-F-1.
Richmond, VA. 140 pp.
05 Kitchel, H.E. 1983. The life history of Fusconaia edgariana
(Mollusca:Bivalvia) from the North Fork Holston River, Smyth Co.,
VA. MS Thesis, VPI & SU, Blacksburg, VA.
06 Barr, W.C., S.A. Allstedt, G.D. Hickman and D.M. Hill. 1982.
Cumberlandian mollusk conservation program - activity 8: macrofauna
analysis. Tenn. Valley Authority, Knoxville, TN.
07 Dennis, S.D. 1981. Mussel fauna of the Powell River, Tennessee
and Virginia. Sterkiana 71:1-7.
08 Tennessee Valley Authority. June 1979. An evaluation of mussel
populations in the Powell River, Tennessee and Virginia.
Unpublished report available from: Division of Water Resources,
Fisheries and Aquatic Ecology Branch, Norris, TN 37828. 15 pp.
09 Tennessee Valley Authority. Aug. and Nov. 1979. An evaluation of
mussel populations in the Clinch River, Tennessee and Virginia.
Unpubl. report available from: Division of Water Resources,
Fisheries and Aquatic Ecology Branch, Norris, TN 37828. 14 pp.
10 Tennessee Valley Authority. Unpublished field records collected by
Steven Ahlstedt (North Fork Holston and Clinch Rivers). On file at:
Div. of Water Res., Fish and Aquatic Ecol. Branch, Norris, TN
37828.
11 Bates, J. and S.D. Dennis. 1978. The mussel fauna of the Clinch
River, Tennessee and Virginia. Sterkiana 69-70:3-23.
12 Tennessee Valley Authority. 1980. Unpublished field records
compiled by Steven Ahlstedt from the Elk, Paint Rock, Estill Fork,
Sequatchie, Little Rivers and Hurricane Creek. On file at: Office
Nat. Resour., East. Area Field Oper. Group., Norris, TN 37828.
13 Ahlstedt, S.A. and S. Brown. 1980. The naiad fauna of the Powell
River in Virginia and Tennessee (Bivalvia:Unionacea). Bull. Amer.
Malacol. Union 1979:40-43.
14 Ortmann, A.E. 1918. The nayades (freshwater mussels) of the upper
Tennessee drainage with notes on synonymy and distribution. Proc.
Amer. Philos. Soc. Philadelphia 57:521-626.
15 Ortmann, A.E. 1925. The naiad-fauna of the Tennessee River system
below Walden Gorge. Amer. Midl. Nat. 9:321-372.
16 Ahlstedt, Steven A. Jan 20, 1980. Critical habitat
recommendations for the shiny pigtoe pearly mussel Fusconaia
edgariana (Lea 1840). Unpubl. report. on file at: TVA, Office
Nat. Resour., East Area Field Oper. Group, Norris, TN 37828.
Prepared under USFWS Contract No. TV50926A.
17 Neves, Richard J. September 20, 1983. Personal communication.
References - 3 (DRAFT) - References
Species PIGTOE, SHINY
Species Id ESIS404001
Date 13 MAR 96
Assistant Unit Leader. VA Coop. Fishery Research Unit, VPI & SU,
Blacksburg, VA 24061.
18 Stansberry, D.H. 1973. A preliminary report on the naiad fauna of
the Clinch River in the southern Appalachian Mountains of Virginia
and Tennessee (Mollusca:Bivalvia:Unionidae). Bull. Amer. Malacol
Union 1972:20-22.
19 Conrad, T.A. 1834. Description of some new species of freshwater
shells from Alabama, Tennessee, etc. Am. J. Sci. Arts
35(s):338-343.
20 Stansberry, D.H. and W.S. Clench. 1977. The Pleuroceridae and
Unionidae of the Upper South Fork Holston River in Virginia. Bull.
Malacol. Union 1977:75-78.
21 Tennessee Valley Authority. 1980. Freshwater mussels of the
Nolichucky River. Unpublished data on flie at: Office of Natural
Resources, East Area Field Oper. Group, Norris, TN. 14 pp.
22 Isom, B.G., P. Yokley, and P.G. Gooch. 1973. Mussels of the Elk
River basin in Alabama and Tennessee, 1965-1968. Am. Midl. Nat.
89:437-442.
23 Tennessee Valley Authority. 1980. Freshwater mussels of the
Buffalo River. Unpublished data on file at: Office of Natural
Resources, East Area Field Oper. Group, Norris, TN. 14 pp.
24 Tennessee Valley Authority. 1981. Freshwater mussels of the
Holston River. Unpublished data on file at: Office of Natural
Resources, East Area Field Oper. Group, Norris, TN. 14 pp.
25 Cairns, J., J.S. Crossman, K.L. Dickson, and E.E. Herricks. 1971.
The recovery of damaged streams. Assoc. Southeast. Biolog. Bull.
18-79-106.
26 Neves, R.J. 1984. Unpublished data. Assistant Unit Leader.
VA Coop. Fishery Research Unit, VPI & SU, Blacksburg, VA 24061.
References - 4