Description

Taxonomy

Kingdom	Phylum	Class	Order	Family	Genus
Animalia	Chordata	Osteichthyes	Salmoniformes	Salmonidae	Oncorhynchus

Synonyms

Salmo kisutch; Salmo tsuppitch

Invasion History

Chesapeake Bay Status

First Record	Population	Range	Introduction	Residency	Source Region	Native Region	Vectors
1985	Failed	Unknown	Introduced	Regular Resident	North America	Asia-North America	Fisheries(Fisheries Intentional)

History of Spread

Oncorhynchus kisutch (Coho Salmon, Silver Salmon) is an anadromous fish, with a native spawning range in: 'Arctic and Pacific drainages; Cape Hope AK to Monterey Bay CA. Also in northeast Asia' (Page and Burr 1991), while the adults range widely in the cooler waters of the North Pacfic. It has been widely introduced outside its range in North America by state agencies, especially in recent decades. After many unsuccessful stockings of O. tshawytscha (Chinook Salmon), in the Eastern US,O. kisutch or 'Silver' Salmon was regarded as possibly better adapted to East Coast river conditions (Smith 1907), and stocked from 'Maine to Maryland' in the early 1900's. This salmon was stocked in the Great Lakes in 1933, but no reproducing populations occurred until more extensive stocking there in 1966 (Mills et al. 1993). This fish was also stocked at several New England locations in the 70's and 80's including the North River MA and Lamprey River, NH (Raasch and Altemus 1991), where some reproduction has been reported. It is also reared for aquaculture in the New England region and northwards. Just outside the Chesapeake watershed. O. kisutch was stocked in Philpott Reservoir and Smith Mountain Lake VA, in the Ohio drainage 1968. The last fish was caught 1973 (Jenkins and Burkhead 1993). Altogether, O. kisutch has been introduced to non-native drainages in at least 32 states, but aside from the Great Lakes populations, most of these efforts have been unsuccessful (Fuller et al. 1999). They are established in rivers in France, and possibly also in Chile (Lever 1996).

Scott and Crossman (1973) mention introductions from 'Maine to Maryland' in the early 1900's but we've found little documentation of these introductions so far. However, according to United States Fish Commission records, 100,000 O. kisutch were shipped to PA in 1908 and 75,000 in 1909 (Bowers 1910; Bowers 1911). Most of these fish were apparently stocked in the Delaware River (Bowers 1910; Bowers 1911a), but some (1,000+ fish) were released in the Susquehanna drainage.

York River- One specimen was caught at the mouth of the Back River, a York tributary. This fish had been stocked in the North River estuary MA. The date of capture was not given, but was probably in the 1980's (Murdy et al. 1997).

Susquehanna River- Oncorhynchus kisutch was Introduced into Harvey's Lake (Central PA) by PA Fish Commission in 1910 (1,000 fish) and again in 1967 (Pennsylvania Department of Fisheries 1911; Denoncourt et al. 1975b), but was not reported from the lower Susquehanna (McKeown 1984).

Delaware River- Oncorhynchus kisutch was extensively stocked (100,000+ fish) in the Delaware drainage PA, in 1908-1911 (Bowers 1911; Pennsylvania Department of Fisheries 1911), but without success. Two fish were caught in Delaware Bay, 1985, strays from MA or NH, where this species was stocked (Raasch and Altemus 1991). In the early 1990s, NJ was considering renewed stocking of Chinook and Coho in the Delaware River (Raasch and Altemus 1991).

Strays in the Chesapeake are possible from anadromous northern stocked or aquaculture populations; or from stocked reservoir populations. History Reference - Bowers 1911 Denoncourt et al. 1975b; Fuller et al. 1999; Jenkins and Burkhead 1993; Lever 1996; McKeown 1984; Mills et al. 1993; Pennsylvania Department of Fisheries 1911; Raasch and Altemus 1991

Invasion Comments

Population Status - Attempts to establish reproductive populations in Chesapeake Bay tributaries have failed, but at least one stray fish from New England stockings has reached the Chesapeake (Murdy et al. 1997).

Ecology

Environmental Tolerances

	For Survival		For Reproduction
	Minimum	Maximum	Minimum	Maximum
Temperature (ºC)	0.0	25.1
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
Sexuality Mode(s)
Mode(s) of Asexual Reproduction
Fertilization Type(s)
More than One Reproduction Event per Year
Reproductive Startegy
Egg/Seed Form

Impacts

Economic Impacts in Chesapeake Bay

Oncorhynchus kisutch (Coho Salmon) is a failed early introduction to Delaware and Chesapeake Bay tributaries. There have been later, failed, introductions to the watershed, status and strays from other stocked populations (Denoncourt et al. 1975; Murdy et al. 1997; Raasch and Altemus 1991), but this species has had no economic impacts in Chesapeake Bay.

References - Denoncourt et al. 1975; Murdy et al. 1997; Raasch and Altemus 1991

Economic Impacts Outside of Chesapeake Bay

Oncorhynchus kisutch (Coho Salmon) is a leading commercial and gamefish in the North Pacific and in river systems from the Sacramento to AK (Scott and Crossman 1973). In its introduced range, it has become an important sport fish in the Great Lakes, and supports put-and-take fisheries in some states with suitable cold, deep lakes (Mills et al. 1993; Scott and Crossman 1973). Oncorhynchus kisutch have been stocked in 32 states (Fuller et al. 1999), and has also become established in France (Lever 1996).

References - Mills et al. 1993; Scott and Crossman 1973

Ecological Impacts on Chesapeake Native Species

Oncorhynchus kisutch (Coho Salmon) has been present only as stocked populations in upland reservoirs (Denoncourt et al. 1975; Stauffer et al. 1978), or as stray juveniles from stocked populations further north (Murdy et al. 1997; Raasch and Altemus 1991). These introductions have had no reprted impacts on native Chesapeake Bay biota.

References- Denoncourt et al. 1975; Murdy et al. 1997; Raasch and Altemus 1991; Stauffer et al. 1978

Ecological Impacts on Other Chesapeake Non-Native Species

Oncorhynchus kisutch (Coho Salmon) has been present only as stocked populations in upland reservoirs (Denoncourt et al. 1975; Stauffer et al. 1978), or as stray juveniles from stocked populations further north (Murdy et al. 1997; Raasch and Altemus 1991). These introductions have had no reprted impacts on introduced Chesapeake Bay biota.

References- Denoncourt et al. 1975; Murdy et al. 1997; Raasch and Altemus 1991; Stauffer et al. 1978

References

Bowers, George (1911) Bureau of Fisheries- Report of the Commissioner of Fisheries for the fiscal year 1909 and special papers., , Washington DC. Pp.

Carlander, Kenneth D. (1969) Handbook of freshwater fishery biology. Vol. 1., In: (Eds.) . , Ames. Pp.

Denoncourt, Robert F.; Robbins, Timothy W.; Hesser, Robert (1975) Recent introductions and reintroductions to the Pennsylvania fish fauna of the Susquehanna River drainage above Conowingo Dam, Proceedings of the Pennsylvania Academy of Science 49: 57-58

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

Fuller, Pam. L.; Nico, Leo; Williams, J. D. (1999) Nonindigenous fishes introduced into inland waters of the United States, , Bethesda MD. Pp.

Jenkins, Robert E.; Burkhead, Noel M. (1993) Freshwater fishes of Virginia., , Bethesda, MD. Pp.

Lee, David S.; Gilbert, Carter R.; Hocutt, Charles H.; Jenkins, Robert E.; McAllister, Don E.; Stauffer, Jay R. (1980) Atlas of North American Freshwater Fishes, , Raleigh. Pp.

Lee, David S.; Platania, S. P.; Gilbert, Carter R.; Franz, Richard; Norden, Arnold (1981) A revised list of the freshwater fishes of Maryland and Delaware, Proceedings of the Southeastern Fishes Council 3: 1-9

Lever, Christopher (1996) Naturalized fishes of the world., , London, England. Pp.

McKeown, Paul E. (1984) Additions to ichthyofauna of the Susquehanna River with a checklist of fishes of the Susquehanna River drainage below Conowingo Dam, Proceedings of the Pennsylvania Academy of Science 58: 187-192

Mills, Edward L.; Leach, Joseph H.; Carlton, James T.; Secor, Carol L. (1993) Exotic species in the Great Lakes: a history of biotic crises and anthropogenic introductions., Journal of Great Lakes Research 19: 1-54

Morrow, James E. (1980) The Freshwater Fishes of Alaska, , Anchorage. Pp.

Murdy, Edward O.; Birdsong, Ray S.; Musick, John A. (1997) Fishes of Chesapeake Bay, , Washington, D.C.. Pp. 57-289

Page, Lawrence M.; Burr, Brooks M. (1991) Freshwater Fishes., , Boston. Pp.

Pennsylvania Department of Fisheries (1911) Silver Salmon, , Harrsiburg PA. Pp.

Raasch, Maynard S.; Altemus, Vaughn L., Sr. (1991) Delaware's freshwater and brackish water fishes: a popular account, , Wilmingotn, Delaware. Pp.

Scott, W. B.; Crossman, E. J. (1973) Freshwater fishes of Canada, , Ottawa. Pp.

Stauffer, Jay R. Jr.; Hocutt, Charles H.; Lee, David S. (1978) The zoogeography of the freshwater fishes of the Potomac River Basin, In: Flynn, Kevin G.; Mason, William T.(Eds.) The Freshwater Potomac: Aquatic Communities and Environmental Stresses. , Rockville, MD. Pp. 44-54