Taxonomy [top]

Kingdom Phylum Class Order Family
Animalia Arthropoda Malacostraca Decapoda Cambaridae

Scientific Name: Orconectes virilis
Species Authority: (Hagen, 1870)
Common Name(s):
English Virile Crayfish

Assessment Information [top]

Red List Category & Criteria: Least Concern ver 3.1
Year Published: 2010
Date Assessed: 2010-06-01
Assessor(s): Adams, S., Schuster, G.A. & Taylor, C.A.
Reviewer(s): Collen, B. & Richman, N.
Contributor(s): Livingston, F., Soulsby, A.-M., Batchelor, A., Dyer, E., Whitton, F., Milligan, H.T., Smith, J., Lutz, M.L., De Silva, R., McGuinness, S., Kasthala, G., Jopling, B., Sullivan, K. & Cryer, G.
Orconectes virilis has been assessed as Least Concern (LC). This species has a wide distribution occurring naturally in Canada and many states in the USA, in addition to introduced populations as far as Europe. It is a habitat generalist, being found in both stream and lake habitats with a variety of substrates utilized. Threats are mainly from water pollution and the introduced Rusty Crayfish (Orconectes rusticus) which is causing localized reductions in fecundity and displacement. It is harvested commercially from the wild, but it is unclear at what tonnage this is harvested. However, due to this species' wide distribution and dispersed localized threats, it has many stable subpopulations persisting.

Geographic Range [top]

Range Description: This species is found widely in Canada. It is found from Alberta to Quebec (Taylor et al. 2005). It is also widespread in North America, where it occurs from New York in the north to Texas in the south (Taylor et al. 2005). Its most western reach is Utah (Taylor et al. 2005).

This species has also been introduced to other areas in the US including, but also Mexico and Europe (Taylor et al. 2005). The native extent of occurrence (EOO) of this species has been estimated to exceed 11 million km2, not including the wide ranging introduced regions. 


Countries occurrence:
Canada (Alberta, Manitoba, Ontario, Québec, Saskatchewan); United States (Alabama - Introduced, Arkansas - Introduced, California - Introduced, Colorado, Connecticut - Introduced, Illinois, Indiana, Iowa, Kansas, Kentucky, Maine - Introduced, Maryland - Introduced, Michigan, Montana, Nebraska, New Hampshire - Introduced, New Jersey - Introduced, New York, Ohio, Oklahoma, Pennsylvania - Introduced, Rhode Island - Introduced, Tennessee - Introduced, Utah - Introduced, Vermont - Present - Origin Uncertain, Virginia - Introduced, West Virginia - Introduced, Wisconsin, Wyoming)
France (France (mainland)); Mexico; Sweden
Continuing decline in area of occupancy (AOO): No
Extreme fluctuations in area of occupancy (AOO): No
Estimated extent of occurrence (EOO) - km2: 11725627
Continuing decline in extent of occurrence (EOO): No
Extreme fluctuations in extent of occurrence (EOO): No
Continuing decline in number of locations: No
Extreme fluctuations in the number of locations: No
Range Map: Click here to open the map viewer and explore range.

Population [top]

Population: This species is widespread and abundant (Fetzner 2008, Pflieger 1996, Thoma and Jezerinac 2000, Aiken 1965).
Current Population Trend: Stable
Additional data:
Continuing decline of mature individuals: No
Extreme fluctuations: No Population severely fragmented: Unknown

Habitat and Ecology [top]

Habitat and Ecology: This is a generalist species, found in a wide variety of freshwater habitats, primarily streams and lakes, but not in swift flows or rapids (Fetzner 2008, Pflieger 1996, Thoma and Jezerinac 2000, Aiken 1965).

It is commonly found on rocky substrates, however in slower rivers it is found on a variety of material such as: mud, silt, and sand (Taylor et al. 2005). Sometimes it constructs burrows in river banks, which have been found to occur at up to 10 m deep (Taylor et al. 2005).
Systems: Freshwater
Continuing decline in area, extent and/or quality of habitat: No

Use and Trade [top]

Use and Trade: Wild populations have been commercially harvested (Taylor et al. 2005).

Threats [top]

Major Threat(s): There are localised threats from competition and pollution in some Canadian watersheds (Taylor et al. 2005). In Ontario it has to compete with Orconectes rusticus, an introduced species (Taylor et al. 2005). Other declines have been attributed to air and water pollution associated with run-off from surrounding watersheds. 
Reduced fecundity has been attributed to acidification of water bodies (Taylor et al. 2005)

Conservation Actions [top]

Conservation Actions: This species has been given the heritage rank of G5, apparently secure, by NatureServe (Taylor et al. 2007, NatureServe 2009) and Currently Stable by the American Fisheries Society (Taylor et al. 2007).

Citation: Adams, S., Schuster, G.A. & Taylor, C.A. 2010. Orconectes virilis. The IUCN Red List of Threatened Species 2010: e.T153831A4551026. . Downloaded on 05 October 2015.
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