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BC Conservation Data Centre: Species Summary


Oncorhynchus mykiss
Rainbow Trout/Steelhead

 
Scientific Name: Oncorhynchus mykiss (Walbaum, 1792)
English Name: Rainbow Trout/Steelhead
 
Classification / Taxonomy
Scientific Name - Concept Reference: Robins, C.R., R.M. Bailey, C.E. Bond, J.R. Brooker, E.A. Lachner, R.N. Lea, and W.B. Scott. 1991. Common and scientific names of fishes from the United States and Canada. American Fisheries Society, Special Publication 20. 183 pp.
Classification Level: Species
Species Group: Vertebrate Animal
Species Code: F-ONMY
Kingdom Phylum Class Order Family
Animalia Craniata Actinopterygii Salmoniformes Salmonidae
   
Conservation Status / Legal Designation
Global Status: G5 (Jul 2022)
Provincial Status: S5 (Mar 2011)
BC List: Yellow
Provincial FRPA list:   
Provincial Wildlife Act:
COSEWIC Status:
SARA Schedule:
General Status Canada: 4 - Secure (2005)
   
Ecology & Life History
General Description:
Global Reproduction Comments: Spawns usually in spring (February-June), or later depending on water temperature and location. Lays 200-9000 eggs (Wydoski and Whitney 1979), which hatch in 3-4 weeks at 10-15 C. Fry emerge from gravel 2-3 weeks after hatching. Many are sexually mature in 2-3 years. See Stearley (1992) for a discussion of the historical ecology and life history evolution of Pacific salmons and trouts (Oncorhynchus).
Global Ecology Comments: Normal life span 5-6 years (Simpson and Wallace 1982). Predation by Caspian terns and double-crested cormorants causes significant mortality of juvenile steelhead in the Columbia River estuary (Ryan et al. 2003). Aggressively defends feeding territories in streams. Has caused contraction of range of native brook trout in southern Appalachian Mountains region (Larson and Moore 1985).
Migration Characteristics:
(Global / Provincial)		 
    Nonmigrant:
    Local Migrant:
    Distant Migrant:
    Within Borders Migrant: 		Y /
Y /
Y /
na /
Global Migration Comments: Anadromous forms migrate up to at least hundreds of miles between spawning streams and nonspawning marine waters. Stream-dwelling trout may spend an entire life in few hundred meters of stream (Moyle 1976). Lake-dwelling trout typically migrate to tributaries to spawn.
Habitats:
(Type / Subtype / Dependence)
Global Habitat Comments: Capable of surviving in a wide range of temperature conditions. Does best where dissolved oxygen concentration is at least 7 ppm. Anadromous populations occur in coastal rivers. Resident populations now inhabit small headwater streams, large rivers, lakes, or reservoirs; often in cool clear lakes and cool swift streams with silt-free substrate. In streams, deep low velocity pools are important wintering habitats (Sublette et al. 1990).

Usually requires a gravel stream riffle for successful spawning. Lake populations move to tributaries to spawn. Eggs are laid in gravel in a depression made by the female. Salinity of 8 ppt is the upper limit for normal development of eggs and alevins (Morgan et al. 1992).
Food Habits: Invertivore: Adult, Immature
Piscivore: Adult, Immature
Global Food Habits Comments: In lakes, feeds mostly on bottom-dwelling invertebrates (e.g., aquatic insects, amphipods, worms, fish eggs, sometimes small fish) and plankton. In streams, feeds primarily on drift organisms. May ingest aquatic vegetation (probably for attached invertebrates). Diet changes seasonally. In the ocean, the diet consists of fishes and crustaceans.
Global Phenology:
Global Phenology Comments: May feed at any time throughout a 24-hour period, but usually feeds most actively around dusk.
Provincial Phenology:
(1st half of month/
2nd half of month)
Colonial Breeder: N
Length(cm)/width(cm)/Weight(g): 100/ /
Elevation (m) (min / max): Global: 
Provincial: 
   
 
Distribution
Endemic: N
Global Range Comment: Native to streams along the Pacific coast of North America from the Kuskokwim River, Alaska, south to northern Baja California; also the upper Mackenzie River drainage (Arctic basin), Alberta and British Columbia, and endorheic (i.e. having no outflow of water) basins of southern Oregon (Page and Burr 1991). The species has been widely introduced and established in suitable habitats all over the world (Lee et al. 1980). At sea, O. mykiss occurs throughout the North Pacific above 40° N from the North American coast to the Sea of Okhotsk (Burgner et al. 1992); it is most abundant in the Gulf of Alaska and eastern part of the North Pacific, conforming to the 5°C isotherm in the north and 15°C isotherm in the south. Seasonal shifts in distribution are correlated with changes in water temperature (Sutherland 1973).
 
Authors / Contributors
Global Information Author: Hammerson, G.
Last Updated: Jan 05, 2004
Provincial Information Author:
Last Updated:
   
References and Related Literature
Barnhart, R. A. 1986. Species profiles: life histories and environmental requirements of coastal fishes and invertebrates (Pacific Southwest)--steelhead. U.S. Fish and Wildlife Service Biological Report 82(11.60).
Behnke, R. J. 1992. Native trout of western North America. American Fisheries Society Monograph 6. xx + 275 pp.
Currens, K. P., C. B. Schreck, and H. W. Li. 1990. Allozyme and morphological divergence of rainbow trout (Oncorhynchus mykiss) above and below waterfalls in the Deschutes River, Oregon. Copeia 1990:730-746.
Larson, G. L., and S. E. Moore. 1985. Encroachment of exotic rainbow trout into stream populations of native brook trout in the southern Appalachian Mountains. Transactions of the American Fisheries Society 114:195-203.
Leary, R. F., W. R. Gould, and G. K. Sage. 1996. Success of basibranchial teeth in indicating pure populations of rainbow trout and failure to indicate pure populations of westslope cutthroat trout. North American Journal of Fisheries Management 16:210-213.
Lee, D. C., and J. Hyman. 1992. The stochastic life-cycle model (SLCM): simulating the population dynamics of anadromous salmonids. United States Department of Agriculture, Forest Service, Intermountain Research Paper INT-459, Ogden, Utah. 30 pp.
Lee, D. S., C. R. Gilbert, C. H. Hocutt, R. E. Jenkins, D. E. McAllister, and J. R. Stauffer, Jr. 1980. Atlas of North American freshwater fishes. North Carolina State Museum of Natural History, Raleigh, North Carolina. i-x + 854 pp.
MacCrimmon, H.R. 1971. World distribution of rainbow trout, Salmo gairdneri. Journal of the Fisheries Research Board of Canada 28(5):663-704.
MacCrimmon, H.R. 1972. World distribution of rainbow trout, Salmo gairdneri: Further observations. Journal of the Fisheries Research Board of Canada 29(12): 1788-1791.
McAfee, W. R. 1966. Rainbow trout. pp. 192-215 in A. Calhoun (editor), Inland fisheries management, California Department of Fish and Game, Sacramento, California. 546 pp.
Metcalfe, C. D. 1989. Tests for predicting carcinogenicity in fish. Reviews in Aquatic Sciences 1(1):111-129.
Morgan, J. D., J. O. T. Jensen, and G. K. Iwama. 1992. Effects of salinity on aerobic metabolism and development of eggs and alevins of steelhead trout (Oncorhynchus mykiss) and fall chinook salmon (Oncorhynchus tshawytscha). Canadian Journal of Zoology 70(7):1341-1346.
Morrow, J.E. 1980. The freshwater fishes of Alaska. Alaska Northwest Publishing Company, Anchorage, AK. 248 pp.
Moyle, P. B. 1976a. Inland fishes of California. University of California Press, Berkeley, California. 405 pp.
National Marine Fisheries Service (NMFS). 11 February 2000c. Threatened status for one evolutionarily significant unit of steelhead in California. Federal Register 65(29):6960-6975..
National Marine Fisheries Service (NMFS). 18 August 1997. Listing of several Evolutionary [sic] Significant Units (ESUs) of west coast steelhead. Federal Register 62(159):43937-43954.
Nehlsen, W., J. E. Williams, and J. A. Lichatowich. 1991. Pacific salmon at the crossroads: stocks at risk from California, Oregon, Idaho, and Washington. Fisheries 16(2):4-21.
Page, L. M., and B. M. Burr. 1991. A field guide to freshwater fishes: North America north of Mexico. Houghton Mifflin Company, Boston, Massachusetts. 432 pp.
Rainbow Trout. 1999. B.C. Fish Facts. Conserv. Sect., Fish. Manage. Branch, B.C. Minist. Fish. 2pp.
Robins, C.R., R.M. Bailey, C.E. Bond, J.R. Brooker, E.A. Lachner, R.N. Lea, and W.B. Scott. 1991. Common and scientific names of fishes from the United States and Canada. American Fisheries Society, Special Publication 20. 183 pp.
Scott, W. B., and E. J. Crossman. 1973. Freshwater fishes of Canada. Fisheries Research Board of Canada, Bulletin 184. 966 pp.
Shapovalov, L. and A.C. Taft. 1954. The life history of the steelhead rainbow trout and silver salmon with special reference to Waddell Creek, California, and recommendations for their management. California Department of Fish and Game, Fish Bulletin 98:1-375.
Simpson, J. and R. Wallace. 1982. Fishes of Idaho. The University Press of Idaho, Moscow, Idaho. 238 pp.
Slaney, T. L., K. D. Hyatt, T. G. Northcote, and R. J. Fielden. 1996. Status of anadromous salmon and trout in British Columbia and Yukon. Fisheries 21(10):20-35.
Smith, G. R., and R. F. Stearley. 1989. The classification and scientific names of rainbow and cutthroat trouts. Fisheries (Bethesda) 14(1):4-10.
Stearley, R. F. 1992. Historical ecology of Salmoninae, with special reference to Oncorhynchus. Pages 622-658 in R.L. Mayden, editor. Systematics, historical ecology, and North American freshwater fishes. Stanford University Press, Stanford, California. xxvi + 969 pp.
Steelhead Trout. 1999. B.C. Fish Facts. Conserv. Sect., Fish. Manage. Branch, B.C. Minist. Fish. 2pp.
Stoltz, J., and J. Schnell (eds.). 1991. Trout: The Wildlife Series. Stackpole Books, Harrisburg, Pennsylvania. 384 pp.
Stow, C. A., S. R. Carpenter, L. A. Eby, J. F. Amrhein, and R. J. Hesselberg. 1995. Evidence that PCBc are approaching stable concentrations in Lake Michigan fishes. Ecological Applications 5:248-260.
Sublette, J. E., M. D Hatch, and M. Sublette. 1990. The fishes of New Mexico. University New Mexico Press, Albuquerque, New Mexico. 393 pp.
U.S. Fish and Wildlife Service (USFWS). 16 November 1998. 90-day finding on a petition to list the redband trout in the Great Basin as threatened or endangered. Federal Register 63(220):63657-63659.
Williams, J. E., J. A. Lichatowich, and W. Nehlsen. 1992b. Declining salmon and steelhead populations: new endangered species concerns for the West. Endangered Species Update 9(4):1-8.
Wishard, L.N., J.E. Seeb, F.M. Utter and D. Stefan 1984. A genetic investigation of suspected redband trout populations. Copeia 1984(1):120-132.
Wydoski, R. S., and R. R. Whitney. 1979. Inland fishes of Washington. The University of Washington Press, Seattle. 220 pp.
 

Please visit the website Conservation Status Ranks for definitions of the data fields used in this summary report.

Suggested Citation:

B.C. Conservation Data Centre. 2004. Species Summary: Oncorhynchus mykiss. B.C. Minist. of Environment. Available: https://a100.gov.bc.ca/pub/eswp/ (accessed Sep 9, 2025).