Description
Synonymy - All Pacific trouts (excluding Charrs; Salvelinus spp.) have been recently moved into the Pacific salmon genus Oncorhynchus (Jenkins and Burkhead 1993).
Taxonomy
| Kingdom | Phylum | Class | Order | Family | Genus |
|---|---|---|---|---|---|
| Animalia | Chordata | Osteichthyes | Salmoniformes | Salmonidae | Oncorhynchus |
Synonyms
Invasion History
Chesapeake Bay Status
| First Record | Population | Range | Introduction | Residency | Source Region | Native Region | Vectors |
|---|---|---|---|---|---|---|---|
| 1992 | Unknown | Expanding | Introduced | Unconfirmed | North America | North America | Fisheries(Fisheries Intentional) |
History of Spread
Oncorhynchus clarki (Cutthroat Trout) is native to Arctic and Pacific drainages from Prince William Sound AK to the Eel River in northern CA. Freshwater populations range through Rocky Mountains in Hudson Bay, Missisippi River, Great Basin, and Pacific Basins from south Alberta to the Rio Grande drainage (Page and Burr 1991). This species is widely introduced outside its native range, established in Quebec in 1940's (Scott and Crossman 1973), but now extinct (Dumont 1988), with scattered introductions elsewhere. Some fish were propagated in 1890-94, and some escaped at the United States Fish Commission Hatchery in Wytheville VA (Ohio drainage), but none are known to have become established in VA (Jenkins and Burkhead 1993).
Potomac River - O. clarki was recently stocked (1992 to present) by Maryland Department of Natural Resources in Piedmont tributaries of the Potomac (North Branch Potomac River, and Murleys Branch Run, Allegany County), and has had some successful reproduction (Kazyak 1995; USGS Florida Caribbean Science Center 2001).
Susquehanna River - O. clarki was stocked in Center and Susquehanna counties (Fowler 1919), but apparently did not become established, and was not on Denoncourt and Cooper's (1975) checklist.
History References - Denoncourt and Cooper 1975; Fowler 1919; Jenkins and Burkhead 1993; Kazyak 1995; Scott and Crossman 1973; USGS Florida Caribbean Science Center 2001
Invasion Comments
Native Region - Arctic & Pacific drainages; Prince William Sound AK to Eel River; northern CA; Freshwater populations range through Rocky Mountains in Hudson Bay, Missisippi River, Great Basin, and Pacific Basins from south Alberta to Rio Grande drainage (Page and Burr 1991).
Invasion Status - Oncorhynchus clarki might be a potential stray in tidal Potomac if it spreads or is more widely stocked. However, it is unlikely to reproduce on the Coastal Plain (Kazyak 1995 personal communication).
Ecology
Environmental Tolerances
| For Survival | For Reproduction | |||
|---|---|---|---|---|
| Minimum | Maximum | Minimum | Maximum | |
| Temperature (ºC) | 0.0 | 10.0 | 5.0 | |
| Salinity (‰) | 0.0 | 35.0 | 0.0 | 0.0 |
| Oxygen | ||||
| pH | ||||
| Salinity Range | fresh-oligo |
Age and Growth
| Male | Female | |
|---|---|---|
| Minimum Adult Size (mm) | ||
| Typical Adult Size (mm) | ||
| Maximum Adult Size (mm) | ||
| Maximum Longevity (yrs) | ||
| Typical Longevity (yrs |
Reproduction
| Start | Peak | End | |
|---|---|---|---|
| Reproductive Season | |||
| Typical Number of Young Per Reproductive Event |
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| Sexuality Mode(s) | |||
| Mode(s) of Asexual Reproduction |
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| Fertilization Type(s) | |||
| More than One Reproduction Event per Year |
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| Reproductive Startegy | |||
| Egg/Seed Form |
Impacts
Economic Impacts in Chesapeake Bay
Oncorhynchus clarki (Cutthroat Trout) is very unlikely to occur in Chesapeake Bay, but could become a valued sportfish in parts of the Chesapeake drainage (mountains and upper Piedmont) if it continues to reproduce (Kazyak 1995).
References- Kazyak 1995
Economic Impacts Outside of Chesapeake Bay
Oncorhynchus clarki (Cutthroat Trout) is an esteemed sport fish in its native range and where stocked populations have become established (Scott and Crossman 1973). Introductions to eastern North America have been largely unsuccessful (Fuller et al. 1999).
References- Fuller et al. 1999; Scott and Crossman 1973
Ecological Impacts on Chesapeake Native Species
Oncorhynchus clarki (Cutthroat Trout) is a potential stray in the uppermost tidal fresh Potomac (Kazyak 1995), but is likely to have no ecological impacts there. In Piedmont and Mountain (MD) streams, predation on native fishes and invertebrates and competition with native brook trout (Salvelinus fontinalis) is possible.
References- Kazyak 1995
Ecological Impacts on Other Chesapeake Non-Native Species
Oncorhynchus clarki (Cutthroat Trout) is likely to have no impacts on introduced fishes of tidal waters of Chesapeake Bay, but competition with introduced rainbow trout (Oncorhynchus mykiss) in Piedmont and Mountain streams is possible.
References
Carlander, Kenneth D. (1969) Handbook of freshwater fishery biology. Vol. 1., In: (Eds.) . , Ames. Pp.Denoncourt, Robert F.; Cooper, Edwin L. (1975) A review of the literature and checklist of fishes of the Susquehanna River drainage above Conowingo Dam, Proceedings of the Pennsylvania Academy of Science 49: 121-125
2002 Nonindigenous aquatic species. Web page: http://nas.er.usgs.gov/queries/SpFactSheet.asp?speciesID=1261
Fowler, Henry W. (1919) A list of the fishes of Pennsylvania, Proceedings of the Biological Society of Washington 32: 49-74
Jenkins, Robert E.; Burkhead, Noel M. (1993) Freshwater fishes of Virginia., , Bethesda, MD. Pp.
1995 Telephone conservation- Nonindigenous fishes in the Chesapeake Bay watershed.
Page, Lawrence M.; Burr, Brooks M. (1991) Freshwater Fishes., , Boston. Pp.
Scott, W. B.; Crossman, E. J. (1973) Freshwater fishes of Canada, , Ottawa. Pp.