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Big Sandy crayfish. Photo by Zachary Loughman, West Liberty University.

Big Sandy crayfish

Cambarus callainus

  • Taxa: Crustacea
  • Range: Kentucky
  • Status: Threatened

The Big Sandy crayfish (Cambarus callianus) is a freshwater crustacean found in streams and rivers in the Appalachian region of Kentucky, Virginia, and West Virginia. The Fish and Wildlife Service has worked with state partners to determine where this dynamic creature is found, and whether it is in danger of extinction. In May 2016, the Service listed the Big Sandy crayfish as a threatened species, protected under the Endangered Species Act.


Like all crayfish found in North America, the adult big sandy crayfish resembles a miniature lobster, ranging from 3 to 4 inches in size. Its shell is an olive brown to light green color, with blue and red accents around its eyes and legs.


A wide, shallow stream cuts through a valley banked by trees with fallen leaves.
The Dry Fork stream in McDowell County, West Virginia, supports a Big Sandy crayfish population.

The Big Sandy Crayfish needs clean, medium-sized streams and rivers for its social reproductive, and energetic needs. They are usually found in faster moving sections of the water, in areas with large boulders and rocks, and little sedimentation or pollution. The stream reaches are at higher elevations in the Appalachian mountain region, in areas with steep hills and ridges that are dissected by a network of deeply cut valleys.


Big Sandy crayfish are opportunistic omnivores, which means they feed on both plants and animals, living and dead, that are readily available in their habitat.

Historical range

Records of the Big Sandy crayfish’s presence in from the Virginia portions of the Big Sandy basin date to 1937, when a single specimen was collected from the Russell Fork drainage in Dickenson County, Virginia. A series of surveys conducted in following years confirmed its presence in West Virginia and Kentucky. The Big Sandy crayfish once had a wider range, but widespread habitat loss and fragmentation of its streams have significantly reduced places where it can be found.

Current range

The Big Sandy crayfish is known only from the Big Sandy River basin in eastern Kentucky, southwestern Virginia, and southern West Virginia. The main river and its streams flow northward until it joins with the Ohio River.

Conservation challenges

​Historical and ongoing erosion and sedimentation from mining, timber harvesting, unpaved roads, and off-road vehicle (ORV) use have degraded the majority of the streams in these crayfishes’ historical ranges, making them unsuitable for the crayfishes’ survival. Though coal extraction in the region has declined from the highs of the 20th century, ongoing and legacy effects of coal mining, including the erosion from closed and abandoned mine lands, are expected to continue. Other activities that may cause erosion and sedimentation, including natural gas development, highway construction, and ORV use, also are expected to continue or increase. It also is likely that general water quality problems such as chemical drainage from mine lands, sewage discharges, and runoff from roads may continue to contribute to the decline of these species.

​The isolated, small populations of both crayfishes make them vulnerable to single catastrophic events like coal slurry spills or to ongoing activities that degrade habitat over time, either of which can wipe out crayfish populations. Suitable sites continue to be fragmented by dams and their associated reservoirs in the watersheds, reducing gene flow and making natural dispersal between sites highly unlikely or impossible without human intervention.


​The Big Sandy crayfish is state-listed as endangered in Virginia and recognized as a species of concern in Kentucky. Only the Virginia designation provides legal protections, which require projects within known Big Sandy crayfish habitat to include actions that reduce or eliminate effects to the species. The species’ habitat is afforded some federal protection under the Clean Water Act and the Surface Mining Control and Reclamation Act, as well as some protection from various other state erosion and sedimentation regulations and best management practices. While these regulations and best management practices help improve overall water quality, they have not been sufficient to alleviate the threats to the species. The following activities can reduce threats to this species, potentially improving its conservation status:

  • Drive ORVs and vehicles on designated trails and not through or in streams.
  • Don’t dump chemicals into streams, and do report spills to state environmental protection agencies.
  • During timber harvest, construction, or other projects, implement best management practices for sediment and erosion control.
  • Start a watershed group or assist in stream and water quality monitoring efforts.
  • Plant trees and other native woody vegetation along stream banks to help restore and preserve water quality.
  • Replace or remove culverts and low-water bridge crossings that are barriers to passage for these species, fishes, and other aquatic organisms.

Other resources

Federal Register notices

The following Federal Register documents were automatically gathered by searching the Federal Register Official API with this species’ scientific name ordered by relevance. You can conduct your own search on the Federal Register website.

  • We're sorry but an error occurred. Visit the Federal Register to conduct your own search.

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