Dromus dromas - (I. Lea, 1834)
Dromedary Pearlymussel
Other English Common Names: Dromedary Naiad
Taxonomic Status: Accepted
Related ITIS Name(s): Dromus dromas caperatus Lea (TSN 80247) ;Dromus dromas dromas (Lea, 1834) (TSN 80246) ;Dromus dromas (I. Lea, 1834) (TSN 80245)
Unique Identifier: ELEMENT_GLOBAL.2.110730
Element Code: IMBIV12010
Informal Taxonomy: Animals, Invertebrates - Mollusks - Freshwater Mussels
 
Kingdom Phylum Class Order Family Genus
Animalia Mollusca Bivalvia Unionoida Unionidae Dromus
Genus Size: A - Monotypic genus
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Concept Reference
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Concept Reference: Turgeon, D.D., J.F. Quinn, Jr., A.E. Bogan, E.V. Coan, F.G. Hochberg, W.G. Lyons, P.M. Mikkelsen, R.J. Neves, C.F.E. Roper, G. Rosenberg, B. Roth, A. Scheltema, F.G. Thompson, M. Vecchione, and J.D. Williams. 1998. Common and scientific names of aquatic invertebrates from the United States and Canada: Mollusks. 2nd Edition. American Fisheries Society Special Publication 26, Bethesda, Maryland: 526 pp.
Concept Reference Code: B98TUR01EHUS
Name Used in Concept Reference: Dromus dromas
Taxonomic Comments: This species is placed in a monotypic genus closely related to the genus Elliptio.
Conservation Status
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NatureServe Status

Global Status: G1
Global Status Last Reviewed: 28Apr2009
Global Status Last Changed: 25Nov1996
Rounded Global Status: G1 - Critically Imperiled
Reasons: Formerly widespread throughout the Cumberland and Tennessee River systems in Tennessee, Alabama, and Virginia, this species has become extremely rare throughout its present range with only three (possibly two) viable populations remaining. The species is declining at all extant sites apparently because of unmanageable threats, habitat degradation and population sizes below viability levels.
Nation: United States
National Status: N1 (25Nov1996)

U.S. & Canada State/Province Status
Due to latency between updates made in state, provincial or other NatureServe Network databases and when they appear on NatureServe Explorer, for state or provincial information you may wish to contact the data steward in your jurisdiction to obtain the most current data. Please refer to our Distribution Data Sources to find contact information for your jurisdiction.
United States Alabama (SX), Kentucky (S1), Tennessee (S1), Virginia (S1)

Other Statuses

U.S. Endangered Species Act (USESA): LE, XN: Listed endangered, nonessential experimental population (14Jun1976)
Comments on USESA: Listed Endangered throughout its range, except in the free-flowing reach of the Tennessee River from the base of Wilson Dam downstream to the backwaters of Pickwick Reservoir and the lower 5 RM of all tributaries to this reach in Colbert and Lauderdale Counties, Alabama. Here it is listed as an experimental, non-essential population. (USFWS, 2001).

The USFWS, in cooperation with the State of Tennessee and Conservation Fisheries, Inc., announced a final rule to reintroduce this species into its historical habitat in the free-flowing reach of the French Broad River below Douglas Dam to its confluence with the Holston River, Knox County Tennessee, and in the free-flowing reach of the Holston River below Cherokee Dam to its confluence with the French Broad River (Federal Register, 12 September 2007). The proposed rule for this action was published on June 13, 2006.

U.S. Fish & Wildlife Service Lead Region: R4 - Southeast
IUCN Red List Category: CR - Critically endangered
Convention on International Trade in Endangered Species Protection Status (CITES): Appendix I
American Fisheries Society Status: Endangered (01Jan1993)

NatureServe Global Conservation Status Factors

Range Extent: 1000-5000 square km (about 400-2000 square miles)
Range Extent Comments: This species is known from the Cumberland and Tennessee river systems in Tennessee and Virginia. It was once common throughout the Tennessee River system. It is currently known from the middle Cumberland River in Smith County, Tennessee; the Tennessee River in Meigs County, Tennessee; and in the upper Powell and Clinch rivers in Tennessee and Virginia (Parmalee and Bogan, 1998; Jones et al., 2004). In Alabama, it historically occurred in the Tennessee River downstream of Muscle Shoals but has not been reported in Alabama since the 1930s, thus it is likely extirpated; but current reintroduction efforts are underway (Mirarchi et al., 2004).

Area of Occupancy: 26-500 4-km2 grid cells
Area of Occupancy Comments: Reproducing populations occur only in the upper Clinch (158 river km) and Powell Rivers (79 river km) in Tennessee and Virginia above Norris Reservoir (Jones et al., 2004).

Number of Occurrences: 1 - 5
Number of Occurrences Comments: A 1980 survey by Virginia Tech and TVA found nine occurrences in Virginia. Currently the dromedary is reduced to possibly three reproducing populations. Reproducing populations occur only in the upper Clinch (158 river km) and Powell Rivers (79 river km) in Tennessee and Virginia above Norris Reservoir (Jones et al., 2004; USFWS, 1984). Back in 1984, the population in the Tennessee River was considered extremely rare since only three live specimens had been found in the Chickamauga Reservoir below Watts Bar Dam (USFWS, 1984) but this site is likely extirpated. Jones et al. (2004) report that based on shells recovered from aboriginal sites, it was once one of the most abundant species in the Tennessee River. Apparently, it is declining at four remaining populations, only older individuals are found in Tennessee River.

Population Size: 1 - 1000 individuals
Population Size Comments: At least prehistorically, Dromus dromas was one of the most abundant species in the Tennessee River. It is apparently declining or has been eliminated from the 3 or 4 remaining populations (likely fewer than 1000 individuals), with only older, non-reproducing, individuals found in the Tennessee River.

Number of Occurrences with Good Viability/Integrity: Very few (1-3)
Viability/Integrity Comments: Barr et al. (1994) determined (based on 1981 survey data) that viable populations exist in the Powell River. Reproducing populations occur only in the upper Clinch (158 river km) and Powell Rivers (79 river km) in Tennessee and Virginia above Norris Reservoir (Jones et al., 2004; USFWS, 1984).

Overall Threat Impact: Very high - high
Overall Threat Impact Comments: Impoundments, siltation and pollution leading to water quality and habitat deterioration inadequate sewage treatment, coal mining, oil and gas drilling and poor land-use practices. USFWS (1984) cites alteration and destruction of stream habitat due to impoundment of the Tennessee and Cumberland Rivers and tributaries for flood control, navigation, hydroelectric power production, and recreation as the single greatest factor contributing to this species' decline. A second factor that has severely affected this species is siltation. This is especially evident with this species as it requires clean, flowing water over stable, silt-free rubble, gravel, and sand shoals to prevent smothering. Also coal production in the Appalachian region has increased in the last few decades; which results in increased silt runoff. A third factor, although on a much broader scale, is the impact caused by various pollutants. Evidence of pollution and associated mussel disappearance in these areas dates back to Ortmann (1918).

Short-term Trend: Decline of 30-70%
Short-term Trend Comments: USFWS (1984) reported extant populations in the Tennessee, Cumberland, Clinch, and Powell Rivers. Back in 1984, the population in the Tennessee River was considered extremely rare since only three live specimens had been found in the Chickamauga Reservoir below Watts Bar Dam (USFWS, 1984) but this site is likely extirpated. Bogan and Parmalee (1998) and Jones et al. (2004) report that based on shells recovered from aboriginal sites, it was once one of the most abundant species in the Tennessee River. Apparently, it is declining at four remaining populations, only older individuals are found in Tennessee River.

Long-term Trend: Decline of 70-90%
Long-term Trend Comments: Bogan and Parmalee (1998) and Jones et al. (2004) report that based on shells recovered from aboriginal sites, it was once one of the most abundant species in the Tennessee River. Apparently declining at four remaining populations, only older individuals found in Tennessee River. Historically, this species was widespread in the Tennessee and Cumberland Rivers including major tributary streams, but has become increasingly rare throughout its range (USFWS, 1984) including the upper Elk (Isom et al., 1973). It once occurred across Alabama in the Tennessee River and some tributaries but was extirpated from Alabama during the early 1900s, although a reintroduction program is underway (Williams et al., 2008). Ortmann (1925) reported it from the Elk River in Alabama but no museum specimens are known.

Intrinsic Vulnerability: Unknown

Environmental Specificity: Narrow. Specialist or community with key requirements common.
Environmental Specificity Comments: This species only occurs in clean, silt-free, flowing water and is sensitive to changes in water quality (domestic pollution and coal washing) and physical disruption (USFWS, 1984).

Other NatureServe Conservation Status Information

Inventory Needs: Define extent, number and viability in existing population.

Protection Needs: Continue Clinch Valley Bioreserve initiatives to improve water quality and land-use practices through variety of governmental and private partners. Listed Endangered throughout its range, except in the free-flowing reach of the Tennessee River from the base of Wilson Dam downstream to the backwaters of Pickwick Reservoir and the lower 5 RM of all tributaries to this reach in Colbert and Lauderdale Counties, Alabama (USFWS, 2001).

The USFWS, in cooperation with the State of Tennessee and Conservation Fisheries, Inc., proposes to reintroduce this species into its historical habitat in the free-flowing reach of the French Broad River below Douglas Dam to its confluence with the Holston River, Knox County Tennessee, and in the free-flowing reach of the Holston River below Cherokee Dam to its confluence with the French Broad River (USFWS, 2006).

Distribution
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Global Range: (1000-5000 square km (about 400-2000 square miles)) This species is known from the Cumberland and Tennessee river systems in Tennessee and Virginia. It was once common throughout the Tennessee River system. It is currently known from the middle Cumberland River in Smith County, Tennessee; the Tennessee River in Meigs County, Tennessee; and in the upper Powell and Clinch rivers in Tennessee and Virginia (Parmalee and Bogan, 1998; Jones et al., 2004). In Alabama, it historically occurred in the Tennessee River downstream of Muscle Shoals but has not been reported in Alabama since the 1930s, thus it is likely extirpated; but current reintroduction efforts are underway (Mirarchi et al., 2004).

U.S. States and Canadian Provinces

Due to latency between updates made in state, provincial or other NatureServe Network databases and when they appear on NatureServe Explorer, for state or provincial information you may wish to contact the data steward in your jurisdiction to obtain the most current data. Please refer to our Distribution Data Sources to find contact information for your jurisdiction.
Color legend for Distribution Map
Endemism: endemic to a single nation

U.S. & Canada State/Province Distribution
United States ALextirpated, KY, TN, VA

Range Map
No map available.


U.S. Distribution by County Help
State County Name (FIPS Code)
AL Jackson (01071)*, Lauderdale (01077)*, Limestone (01083)*, Madison (01089)*, Morgan (01103)*
KY Clinton (21053)*, Cumberland (21057)*, Livingston (21139)*, Lyon (21143)*, McCreary (21147), Monroe (21171)*, Pulaski (21199)*, Russell (21207)*, Wayne (21231)*
TN Anderson (47001)*, Campbell (47013)*, Claiborne (47025), Clay (47027)*, DeKalb (47041)*, Giles (47055)*, Grainger (47057)*, Hamilton (47065)*, Hancock (47067), Jackson (47087)*, Jefferson (47089)*, Knox (47093)*, Marion (47115)*, Meigs (47121)*, Putnam (47141)*, Rhea (47143), Sevier (47155)*, Smith (47159), Trousdale (47169)
VA Lee (51105), Scott (51169)*
* Extirpated/possibly extirpated
U.S. Distribution by Watershed Help
Watershed Region Help Watershed Name (Watershed Code)
05 Upper Cumberland (05130101)*, Upper Cumberland-Lake Cumberland (05130103)+*, South Fork Cumberland (05130104)+, Obey (05130105)+*, Upper Cumberland-Cordell Hull (05130106)+*, Collins (05130107)*, Caney (05130108)+, Lower Cumberland-Old Hickory Lake (05130201)+, Lower Cumberland-Sycamore (05130202)*, Harpeth (05130204)*, Lower Cumberland (05130205)+*
06 Holston (06010104)+, Pigeon (06010106)*, Lower French Broad (06010107)+*, Watts Bar Lake (06010201)+, Lower Little Tennessee (06010204)*, Upper Clinch (06010205)+, Powell (06010206)+, Lower Clinch (06010207)+, Middle Tennessee-Chickamauga (06020001)+, Hiwassee (06020002)*, Guntersville Lake (06030001)+*, Wheeler Lake (06030002)+*, Upper Elk (06030003)+*, Lower Elk (06030004)+*, Pickwick Lake (06030005)+*, Bear (06030006)*, Lower Tennessee-Beech (06040001)*
+ Natural heritage record(s) exist for this watershed
* Extirpated/possibly extirpated
Ecology & Life History
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Basic Description: A freshwater mussel - dromedary pearlymussel.
General Description: see USFWS (1984)
Reproduction Comments: Females are gravid from October through May and contain 33 to 151 conglutinates/female thus the species is bradytictic. Conglutinates are contained only in water tubes of outer gills, and typically observed in all the water tubes from anterior to posterior portion of the gill. Conglutinates are released one at at a time from late March to late April. This species is one of a few mussels in Lampsilinae that produce modified conglutinates released through the suprabranchial cavity. The species is bradytictic, but females release conglutinates over a relatively short period of time once glochidia are mature (similar to many tachytictic or short-term brooders) (Jones et al., 2004).

Hosts (from Jones et al., 2004 and Watson and Neves, 1998):
Cottus baileyi (black sculpin), Etheostoma blennioides (greenside darter), Etheostoma flabellare (fantail darter), Etheostoma simoterum (snubnose darter), Percina aurantiaca (tangerine darter), Percina burtoni (blotchside logberch), Percina caprodes (Logperch), Percina copelandi (channel darter), Percina evides (gilt darter), Percina roanoka (roanoke darter).

Habitat Type: Freshwater
Non-Migrant: N
Locally Migrant: N
Long Distance Migrant: N
Riverine Habitat(s): BIG RIVER, MEDIUM RIVER, Riffle
Special Habitat Factors: Benthic
Habitat Comments: This is a riffle dwelling species occurring at shoals with sand and gravel and moderate current velocities, but also found in deeper, slower moving water in Tennessee. It is most often observed in clean, fast-flowing water in substrates that contain relatively firm rubble, gravel, and stable, clean substrates (USFWS, 2004).
Adult Phenology: Diurnal
Phenology Comments: Live to 25 years (Jones et al., 2004).
Length: 8.3 centimeters
Economic Attributes Not yet assessed
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Management Summary
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Stewardship Overview: This species was listed as federally endangered in the U.S. in 1976 and a recovery plan was created (USFWS, 1984).

Listed Endangered throughout its range, except in the free-flowing reach of the Tennessee River from the base of Wilson Dam downstream to the backwaters of Pickwick Reservoir and the lower 5 RM of all tributaries to this reach in Colbert and Lauderdale Counties, Alabama (USFWS, 2001).

The USFWS, in cooperation with the State of Tennessee and Conservation Fisheries, Inc., proposes to reintroduce this species into its historical habitat in the free-flowing reach of the French Broad River below Douglas Dam to its confluence with the Holston River, Knox County Tennessee, and in the free-flowing reach of the Holston River below Cherokee Dam to its confluence with the French Broad River (USFWS, 2006).

Biological Research Needs: Biological and ecological studies to determine life history and population traits.
Population/Occurrence Delineation
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Group Name: Freshwater Mussels

Use Class: Not applicable
Minimum Criteria for an Occurrence: Occurrences are based on some evidence of historical or current presence of single or multiple specimens, including live specimens or recently dead shells (i.e., soft tissue still attached and/or nacre still glossy and iridescent without signs of external weathering or staining), at a given location with potentially recurring existence. Weathered shells constitute a historic occurrence. Evidence is derived from reliable published observation or collection data; unpublished, though documented (i.e. government or agency reports, web sites, etc.) observation or collection data; or museum specimen information.
Mapping Guidance: Based on the separation distances outlined herein, for freshwater mussels in STANDING WATER (or backwater areas of flowing water such as oxbows and sloughs), all standing water bodies with either (1) greater than 2 km linear distance of unsuitable habitat between (i.e. lotic connections), or (2) more than 10 km of apparently unoccupied though suitable habitat (including lentic shoreline, linear distance across water bodies, and lentic water bodies with proper lotic connections), are considered separate element occurrences. Only the largest standing water bodies (with 20 km linear shoreline or greater) may have greater than one element occurrence within each. Multiple collection or observation locations in one lake, for example, would only constitute multiple occurrences in the largest lakes, and only then if there was some likelihood that unsurveyed areas between collections did not contain the element.

For freshwater mussels in FLOWING WATER conditions, occurrences are separated by a distance of more than 2 stream km of unsuitable habitat, or a distance of more than 10 stream km of apparently unoccupied though suitable habitat. Standing water between occurrences is considered suitable habitat when calculating separation distance for flowing water mussel species unless dispersal barriers (see Separation Barriers) are in place.

Several mussel species in North America occur in both standing and flowing water (see Specs Notes). Calculation of separation distance and determination of separation barriers for these taxa should take into account the environment in which the element was collected. Juvenile mussels do not follow this pattern and juveniles are typically missed by most standard sampling methods (Hastie and Cosgrove, 2002; Neves and Widlak, 1987), therefore juvenile movement is not considered when calculating separation distance.

Separation Barriers: Separation barriers within standing water bodies are based solely on separation distance (see Separation Distance-suitable, below). Separation barriers between standing water bodies and within flowing water systems include lack of lotic connections, natural barriers such as upland habitat, absence of appropriate species specific fish hosts, water depth greater than 10 meters (Cvancara, 1972; Moyle and Bacon, 1969) or anthropogenic barriers to water flow such as dams or other impoundments and high waterfalls.
Separation Distance for Unsuitable Habitat: 2 km
Separation Distance for Suitable Habitat: 10 km
Alternate Separation Procedure: None
Separation Justification: Adult freshwater mussels are largely sedentary spending their entire lives very near to the place where they first successfully settled (Coker et al., 1921; Watters, 1992). Strayer (1999) 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. Movement occurs with the impetus of some stimulus (nearby water disturbance, physical removal from the water such as during collection, exposure conditions during low water, seasonal temperature change or associated diurnal cycles) and during spawning. Movement is confined to either vertical movement burrowing deeper into sediments though rarely completely beneath the surface, or horizontal movement in a distinct path often away from the area of stimulus. Vertical movement is generally seasonal with rapid descent into the sediment in autumn and gradual reappearance at the surface during spring (Amyot and Downing, 1991; 1997). Horizontal movement is generally on the order of a few meters at most and is associated with day length and during times of spawning (Amyot and Downing, 1997). Such locomotion plays little, if any, part in the distribution of freshwater mussels as these limited movements are not dispersal mechanisms. Dispersal patterns are largely speculative but have been attributed to stream size and surface geology (Strayer, 1983; Strayer and Ralley, 1993; van der Schalie, 1938), utilization of flow refuges during flood stages (Strayer, 1999), and patterns of host fish distribution during spawning periods (Haag and Warren, 1998; Watters, 1992). Lee and DeAngelis (1997) modeled the dispersal of freshwater into unoccupied habitats as a traveling wave front with a velocity ranging from 0.87 to 2.47 km/year (depending on mussel life span) with increase in glochidial attachment rate to fish having no effect on wave velocity.

Nearly all mussels require a host or hosts during the parasitic larval portion of their life cycle. Hosts are usually fish, but a few exceptional species utilize amphibians as hosts (Van Snik Gray et al., 2002; Howard, 1915) or may metamorphose without a host (Allen, 1924; Barfield et al., 1998; Lefevre and Curtis, 1911; 1912). Haag and Warren (1998) found that densities of host generalist mussels (using a variety of hosts from many different families) and displaying host specialists (using a small number of hosts usually in the same family but mussel females have behavioral modifications to attract hosts to the gravid female) were independent of the densities of their hosts. Densities of non-displaying host specialist mussels (using a small number of hosts usually in the same family but without host-attracting behavior) were correlated positively with densities of their hosts. Upstream dispersal of host fish for non-displaying host specialist mussels could, theoretically, transport mussel larvae (glochidia) over long distances through unsuitable habitat, but it is unlikely that this occurs very often. D. Strayer (personal communication) suggested a distance of at least 10 km, but a greater distance between occurrences may be necessary to constitute genetic separation of populations. As such, separation distance is based on a set, though arbitrary, distance between two known points of occurrence.

Date: 18Oct2004
Author: Cordeiro, J.
Notes: Contact Jay Cordeiro (jay_cordeiro@natureserve.org) for a complete list of freshwater mussel taxa sorted by flow regime.
Population/Occurrence Viability
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U.S. Invasive Species Impact Rank (I-Rank) Not yet assessed
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Authors/Contributors
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NatureServe Conservation Status Factors Edition Date: 28Apr2009
NatureServe Conservation Status Factors Author: Cordeiro, J.
Element Ecology & Life History Edition Date: 17Oct2006
Element Ecology & Life History Author(s): Cordeiro, J.

Zoological data developed by NatureServe and its network of natural heritage programs (see Local Programs) and other contributors and cooperators (see Sources).

References
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  • Alabama Department of Conservation and Natural Resources, Division of Wildlife and Freshwater Fisheries. 2015. Alabam's Wildlife Action Plan 2015-2025. Alabama Department of Conservation and Natural Resources, Division of Wildlife and Freshwater Fisheries. Montgomery, Alabama. 514 pages. [Available online at http://www.outdooralabama.com/sites/default/files/AL%20SWAP%20FINAL%20POST-REVIEW%2004-22-2016.pdf}

  • Gordon, M.E. and J.B. Layzer. 1989. Mussels (Bivalvia: Unionoidea) of the Cumberland River review of life histories and ecological relationships. U.S. Fish and Wildlife Service Biological Report, 89(15): 1-99.

  • Howard, A.D. 1915. Some exceptional cases of breeding among the Unionidae. The Nautilus 29:4-11.

  • Isom, B.G., P. Yokley, Jr., and C.H. Gooch. 1973. Mussels of Elk River Basin in Alabama and Tennessee- 1965-1967. American Midland Naturalist 89(2):437-442.

  • Lefevre, G. and W.T. Curtis. 1912. Studies on the reproduction and artificial propogation of fresh-water mussels. Bulletin of the Bureau of Fisheries 30:102-201.

  • Moyle, P. and J. Bacon. 1969. Distribution and abundance of molluscs in a fresh water environment. Journal of the Minnesota Academy of Science 35(2/3):82-85.

  • Ortmann, A.E. 1925. The naiad fauna of the Tennessee River system below Walden Gorge. The American Midland Naturalist, 9(7): 321-371.

  • Parmalee, P.W. and A.E. Bogan. 1998. The freshwater mussels of Tennessee. University of Tennessee Press, Knoxville, Tennesee. 328 pp.

  • Shelton-Nix, E. 2017. Alabama Wildlife, Volume 5. University of Alabama Press, Tuscaloosa, Alabama. 355 pages.

  • Strayer, D. 1983. The effects of surface geology and stream size on freshwater mussel (Bivalvia, Unionidae) distribution in southeastern Michigan, U.S.A. Freshwater Biology 13:253-264.

  • Strayer, D.L. 1999a. Use of flow refuges by unionid mussels in rivers. Journal of the North American Benthological Society 18(4):468-476.

  • Strayer, D.L. and J. Ralley. 1993. Microhabitat use by an assemblage of stream-dwelling unionaceans (Bivalvia) including two rare species of Alasmidonta. Journal of the North American Benthological Society 12(3):247-258.

  • Turgeon, D.D., J.F. Quinn, Jr., A.E. Bogan, E.V. Coan, F.G. Hochberg, W.G. Lyons, P.M. Mikkelsen, R.J. Neves, C.F.E. Roper, G. Rosenberg, B. Roth, A. Scheltema, F.G. Thompson, M. Vecchione, and J.D. Williams. 1998. Common and scientific names of aquatic invertebrates from the United States and Canada: Mollusks. 2nd Edition. American Fisheries Society Special Publication 26, Bethesda, Maryland: 526 pp.

  • U.S. Fish and Wildlife Service (USFWS). 1984. Recovery plan for the Dromedary Pearly Mussel; Dromus dromas, Dromus dromas form caperatus. U.S. Fish and Wildlife Service, Region 4, Atlanta, Georgia.

  • U.S. Fish and Wildlife Service (USFWS). 2001. Endangered and Threatened Wildlife and Plants; establishment of nonessential experimental population status for 16 freshwater mussels and 1 freshwater snail (Anthony's Riversnail) in the free-flowing reach of the Tennessee River below the Wilson Dam, Colbert and Lauderdale Counties, Alabama. Federal Register, 66(115): 32250-32264.

  • U.S. Fish and Wildlife Service (USFWS). 2006. Endangered and threatened wildlife and plants; establishment of nonessential experimental population status for 15 freshwater mussels, 1 freshwater snail, and 5 fishes in the lower French Broad River and in the lower Holston River, Tennessee; Proposed Rule. Federal Register, 71(113): 34195-34230.

  • Van der Schalie, H. 1938a. The naiad fauna of the Huron River in southeastern Michigan. Miscellaneous Publication of the Museum of Zoology, University of Michigan 40:7-78.

  • Watson, B.T. and R.J. Neves. 1998. Fish host identification for two federally endangered unionids in the upper Tennessee River drainage. Triannual Unionid Report, 14: 7

  • Watters, G.T. 1992a. Unionids, fishes, and the species-area curve. Journal of Biogeography 19:481-490.

  • Williams, J. D., A. E. Bogan, and J. T Garner. 2008. Freshwater mussels of Alabama & the Mobile Basin in Georgia, Mississippi, & Tennessee. University of Alabama Press, Tuscaloosa, Alabama. 908 pages.

  • Williams, J.D., M.L. Warren, Jr., K.S. Cummings, J.L. Harris, and R.J. Neves. 1993b. Conservation status of freshwater mussels of the United States and Canada. Fisheries 18(9): 6-22.

References for Watershed Distribution Map
  • Barr, W.C., S.A. Ahlstedt, G.D. Hickman, and D.M. Hill. 1993-1994. Cumberlandian mollusk conservation program. Activity 8: Analysis of macrofauna factors. Walkerana 7(17/18):159-224.

  • Biological Resources Division, USGS. 1997. Database of museum records of aquatic species. Compiled by J. Williams (USGS-BRD, Gainesville, FL).

  • Cicerello, R.R. and G.A. Schuster. 2003. A guide to the freshwater mussels of Kentucky. Kentucky State Nature Preserves Commission Scientific and Technical Series 7:1-62.

  • Jones, J.W., R.J. Neves, S.A. Ahlstedt, and R.A. Mair. 2004. Life history and propagation of the endangered dromedary pearlymussel (Dromus dromas) (Bivalvia: Unionidae). Journal of the North American Benthological Society, 23(3): 515-525.

  • Mirarchi, R.E., J.T. Garner, M.F. Mettee, and P.E. O'Neil. 2004b. Alabama wildlife. Volume 2. Imperiled aquatic mollusks and fishes. University of Alabama Press, Tuscaloosa, Alabama. xii + 255 pp.

  • Parmalee, P.W. and A.E. Bogan. 1998. The Freshwater Mussels of Tennessee. University of Tennessee Press: Knoxville, Tennessee. 328 pp.

  • Williams, J.D., A.E. Bogan, and J.T. Garner. 2008. Freshwater Mussels of Alabama & the Mobile Basin in Georgia, Mississippi & Tennessee. University of Alabama Press: Tuscaloosa, Alabama. 908 pp.

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"Data provided by NatureServe in collaboration with Bruce Patterson, Wes Sechrest, Marcelo Tognelli, Gerardo Ceballos, The Nature Conservancy-Migratory Bird Program, Conservation International-CABS, World Wildlife Fund-US, and Environment Canada-WILDSPACE."

Citation for Amphibian Range Maps of the Western Hemisphere:
IUCN, Conservation International, and NatureServe. 2004. Global Amphibian Assessment. IUCN, Conservation International, and NatureServe, Washington, DC and Arlington, Virginia, USA.

Acknowledgement Statement for Amphibian Range Maps of the Western Hemisphere:
"Data developed as part of the Global Amphibian Assessment and provided by IUCN-World Conservation Union, Conservation International and NatureServe."

NOTE: Full metadata for the Bird Range Maps of North America is available at:
http://www.natureserve.org/library/birdDistributionmapsmetadatav1.pdf.

Full metadata for the Mammal Range Maps of North America is available at:
http://www.natureserve.org/library/mammalsDistributionmetadatav1.pdf.

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