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Home/Species/ New River Crayfish

Cambarus chasmodactylus

James, 1966

New River Crayfish

G4Apparently Secure Found in 4 roadless areas NatureServe Explorer →
G4Apparently SecureGlobal Rank
Least concernIUCN
HighThreat Impact
Identity
Unique IDELEMENT_GLOBAL.2.112361
Element CodeICMAL07130
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryInvertebrate Animal
IUCNLeast concern
Endemicendemic to a single nation
KingdomAnimalia
PhylumArthropoda
ClassMalacostraca
OrderDecapoda
FamilyCambaridae
GenusCambarus
Concept Reference
Hobbs, H. H., Jr. 1989. An Illustrated Checklist of the American Crayfishes (Decapoda: Astacidae, Cambaridae, and Parastacidae). Smithsonian Contributions to Zoology 480:1-236.
Conservation Status
Review Date2010-05-17
Change Date1996-02-19
Edition Date2010-08-05
Edition AuthorsCordeiro, J. (2010); Whittaker, J. C.; C. Taylor
Threat ImpactHigh
Range Extent5000-20,000 square km (about 2000-8000 square miles)
Number of Occurrences21 - 80
Rank Reasons
The species is fairly widespread (10,000-20,000 sq. km), but is endemic to the New River drainage. Although most populations are secure, there is some decline due to development pressure and increased siltation. There are still several dozen occurrences, however, many with decent viability.
Range Extent Comments
Endemic to the New River drainage system, from upper reaches of Greenbrier River, Pocahontas and Monroe counties, West Virginia, south through Virginia to Alleghany, Ashe and Watauga counties, North Carolina.
Occurrences Comments
Jezerinac et al. (1995) recorded species from 33 localities. In West Virginia, it inhabits streams in the Greenbrier River system across high and low elevations and is stable (Loughman and Welsh, 2010). LeGrand et al. (2006) cite rivers and large streams in the New River drainage in North Carolina. In North Carolina, it occurs throughout the New River basin in North Carolina in Watauga, Ashe, and Alleghany Cos. (McGrath, 1998 in 16 of 27 sites, Simmons and Fraley, 2010 in 9 of 13 sites).
Threat Impact Comments
According to Cooper and Cooper (1977), the species is endemic to the New River and requires lotic waters of considerable size. "Although it is now often common within its range, impoundment of these moving waters would eliminate the riffle habitat required by the species. Thus it would almost certainly be eliminated from all areas converted to lentic habitats. Survival of the species in North Carolina might be possible in unimpounded headwater streams of South Fork, but it would be rendered tenuous by isolation from remaining populations elsewhere. Furthermore, its apparent preference for large streams could prevent its establishment in smaller headwaters. Preservation of the North Carolina populations of the species is given added importance by the already limited availability of appropriate habitat in the Virginia and West Virginia portions of its range, and by other apparent encroachments on the few known populations in those states." Another threat may be the bait bucket introduction of non-native species of aggressive crayfish or fish, but there is no indication of this occurring at the present time.
Ecology & Habitat

Description

"This is a relatively large crayfish, with carapace lengths ranging from 30 to 55 mm (1 1/8 to 2 1/8 in) and total body lengths of about 60 to 95 mm (2 3/8 to 3 1/4 in) in adults. The impression of even larger size is enhanced, particularly in breeding males, by the very large chelae, which are commonly much longer than the carapace. The chelae of at least one individual reached a length of 78 mm (over 3 in). As in other members of the subgenus the chelae are further distinctive in having smooth surfaces, almost lacking the ridges and tubercles common to most crayfishes, and in the often enormous gape or space between the fingers for most of their length. Overall body color is 'concolorous blue green tinged with shades of cream to rust' (James 1966). The areola is broad (length about 4 to 6 times width) and densely studded with punctations, and the rostral margins are smooth with no spines or tubercles. As in most members of the genus, the first pleopod of males has two terminal elements recurved at nearly right angles to the main shaft." (Cooper and Cooper, 1977). [LENGTH: to 55 TCL, to 95 TL] [WIDTH: to 16]

Diagnostic Characteristics

Can be distinguished from C. LONGULUS by its "relatively longer fingers on the chelae, with the movable finger being more than twice as long as the mesial margin of the palm. Keys precisely distinguishing the New River Riffle Crayfish from other members of the subgenus are provided by Hobbs (1969, p. 106; 1972, p. 120). Diagnostic illustrations for the species are in James (1966, p. 15 and Plate 1) and Hobbs (1974, p. 92)." (Cooper and Cooper, 1977).

Habitat

Cambarus chasmodactylus can be found in permanent rocky streams often beneath slab rock (Simmons and Fraley, 2010). They are however limited to fast-flowing, often large, turbulent tributaries. (Cooper and Braswell 1995). It does not frequent quiet pools, springs or mountain "feeder brooks" (James 1996).

Ecology

In general crayfish occupy a small home range; are subject to predation by mammals, birds and herptiles. Helms and Creek (2005) found no influence of Cambarus chasmodactylus and coexisting Orconectes cristavarius (and associated differences in diet) on sediment accumulation and benthic invertebrate populations in a large river in North Carolina.

Reproduction

"While there are no published reproductive data for this species itself, the general patterns might be expected to parallel those of its relative," C. LONGULUS, which "has rather well-defined reproductive cycles. Eggs are laid from late April to mid-July, hatching in about three weeks. Sexual maturity is attained in 16 to 17 months, and copulation occurs from September to April. Adults apparently survive through two breeding seasons, with a longevity of 36 or 37 months. Females produce relatively few eggs each season, with a maximum of 45 observed attached to any individual." (Cooper and Cooper, 1977). In North Carolina, Form I males were collected in October in 11-17C (Simmons and Fraley, 2010).
Other Nations (1)
United StatesN4
ProvinceRankNative
North CarolinaS4Yes
West VirginiaS3Yes
VirginiaS3Yes
Threat Assessments
ThreatScopeSeverityTiming
4 - Transportation & service corridorsUnknownUnknownLow (long-term)
4.3 - Shipping lanesUnknownUnknownLow (long-term)
7 - Natural system modificationsUnknownUnknownHigh (continuing)
7.2 - Dams & water management/useUnknownUnknownHigh (continuing)

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Roadless Areas (4)
Virginia (1)
AreaForestAcres
Bear CreekJefferson National Forest18,274
West Virginia (3)
AreaForestAcres
East Fork Of GreenbrierMonongahela National Forest7,167
Little MountainMonongahela National Forest8,172
Middle MountainMonongahela National Forest19,020
References (19)
  1. Cooper, J.E. 2010. Annotated checklist of the crayfishes of North Carolina, and correlations of distributions with hydrologic units and physiographic provinces. Journal of the North Carolina Academy of Science 126(3):69-76.
  2. Cooper, J.E., S.S. Robinson, and J.B. Funderburg (eds.). 1977. Endangered and threatened plants and animals of North Carolina. North Carolina State Museum of Natural History, Raleigh, North Carolina. 444 pp.
  3. Cooper, M. R., and J. E. Cooper. 1977. CAMBARUS (HIATICAMBARUS) CHASMODACTYLUS James, New River riffle crayfish. Pages 204-6 in Cooper, J. E., S. S. Robinson, and J. B. Funderburg (editors). Endangered and threatened plants and animals of North Carolina. North Carolina State Museum of Natural History, Raleigh, Virginia.
  4. Crandall, K. A., and S. De Grave. 2017. An updated classification of the freshwater crayfishes (Decapoda: Astacidea) of the world, with a complete species list. Journal of Crustacean Biology 37(5):615-653.
  5. Helms, B.S. and R.P. Creed. 2005. The effects of 2 coexisting crayfish on an Appalachian river community. Journal of the North American Benthological Society 24(1): 113-122.
  6. Hobbs, H.H. 1969. On the distribution and phylogeny of the crayfish genus <i>Cambarus</i>. Pages 93-178 in Holt, P.C. (editor). Part I: Invertebrates, in The distributional history of the biota of the southern Appalachians. Virginia Polytechnic Institute, Blacksburg, Virginia.
  7. Hobbs, H. H. Jr. 1972. Biota of freshwater ecosystems. Pages 120-1 in Identificational Manual No. 9: Crayfishes (Astacidae) of North and Middle America. EPA.
  8. Hobbs, H.H., Jr. 1974. A checklist of the North American and middle American crayfishes (Decapoda: Astacidae and Cambari dae). Smithsonian Contrib. to Zool. 166:1-161.
  9. Hobbs, H. H., Jr. 1989. An Illustrated Checklist of the American Crayfishes (Decapoda: Astacidae, Cambaridae, and Parastacidae). Smithsonian Contributions to Zoology 480:1-236.
  10. Hobbs, Jr., H. H. 1976a. Crayfishes (Astacidae) of North and Middle America. Biological Methods Branch, Environmental Protection Agency, Cincinnati, Ohio. 173 pp.
  11. James, H. A. 1966. Range and variations of subspecies of CAMBARUS LONGULUS (Decapoda: Astacidae). Proc. U.S. Nat. Mus. 119:1-24.
  12. Jezerinac, R. F., G. W. Stocker, and D. C. Tarter. 1995. The Crayfishes (Decapoda: Cambaridae) of West Virginia. Bulletin of the Ohio Biological Survey, Vol. 10, No. 1. Ohio Biological Survey, College of Biological Sciences, The Ohio State University, and Nongame Wildlife and Natural Heritage Programs, West Virginia Division of Natural Resources, Columbus, Ohio. 193 pp.
  13. Jones, T. Biology Dept. University of Louisville. Belknap Campus. Louisville, KY
  14. LeGrand, H.E., Jr., S.P. Hall, S.E. McRae, and J.T. Finnegan. 2006. Natural Heritage Program List of the Rare Animal Species of North Carolina. North Carolina Natural Heritage Program, Raleigh, North Carolina. 104 pp.
  15. Loughman, Z.J. and S.A. Welsh. 2010. Distribution and conservation standing of West Virginia crayfishes. Southeastern Naturalist 9 (special issue 3):63-78.
  16. McLaughlin, P. A., D. K. Camp, M. V. Angel, E. L. Bousfield, P. Brunel, R. C. Brusca, D. Cadien, A. C. Cohen, K. Conlan, L. G. Eldredge, D. L. Felder, J. W. Goy, T. Haney, B. Hann, R. W. Heard, E. A. Hendrycks, H. H. Hobbs III, J. R. Holsinger, B. Kensley, D. R. Laubitz, S. E. LeCroy, R. Lemaitre, R. F. Maddocks, J. W. Martin, P. Mikkelsen, E. Nelson, W. A. Newman, R. M. Overstreet, W. J. Poly, W. W. Price, J. W. Reid, A. Robertson, D. C. Rogers, A. Ross, M. Schotte, F. Schram, C. Shih, L. Watling, G. D. F. Wilson, and D. D. Turgeon. 2005. Common and Scientific Names of Aquatic Invertebrates from the United States and Canada: Crustaceans. American Fisheries Society Special Publication 31. 545 pp.
  17. Simmons, J.W. and S.J. Fraley. 2010. Distribution, status, and life-history observations of crayfishes in western North Carolina. Southeastern Naturalist 9 (special issue 3):79-126.
  18. Taylor, C. A., G. A. Schuster, J. E. Cooper, R. J. DiStefano, A. G. Eversole, P. Hamr, H. H. Hobbs III, H. W. Robison, C. E. Skelton, and R. F. Thoma. 2007. A reassessment of the conservation status of crayfishes of the United States and Canada after 10+ years of increased awareness. Fisheries 32(8):371-389.
  19. U.S. Fish and Wildlife Service (USFWS). 2011. Endangered and threatened wildlife and plants; partial 90-day finding on a petition to list 404 species in the southeastern United States as threatened or endangered with critical habitat. Federal Register 76(187):59836-59862.