Steelhead Trout

Steelhead Trout or Rainbow Trout or Kamloops Trout (Oncorhynchus mykiss)

Identification:

Juveniles: Large parr marks, including along the dorsal ridge. Spots on the dorsal surface and dorsal fin, but rarely on the caudal fin. Upper jaw does not extend past the hind margin of the eye. No red or yellow markings on throat. Sides usually silver with a pinkish hue along midline.

Adults: Dorsal surface is dark metallic blue. Sides and underparts are silvery to white below the lateral line. Back and dorsal, adipose and caudal fins have bold dark spots. No red or yellow marking on throat. Length usually 20-30 inches.

Rainbow Trout

Spawning adults: Males have a continuous deep pink to red vertical band along each side of the body, also somewhat pointed or hooked snout. Females also have a red band, but it is less vivid than that of the males.

Life History: Variable life histories including river resident Rainbow trout, early and late migrating anadromous Steelhead and lake resident Kamloops trout. Generally spring to summer spawners, from MR.h to August. The female chooses the redd site, usually a gravel bed in a riffle above a pool. She digs the nest, and deposits her eggs as the male fertilizes them. Some individuals may survive to spawn in a second year, but survival rate is generally less than 10%. Fecundity can range from 200 to 12 749 eggs per female (average number around 4200). After emergence, the fry of river resident spawners remain in the spawning streams where they complete their life cycle. The fry of anadromous spawners spend one to four years in fresh water, and then migrate to the ocean. The fry of lake resident spawners can move from the spawning river to the lake almost immediately, by autumn, or spend up to three years in the stream. Sexual maturity is usually reached after three to five years, but can be as early as one year, or as late as six years.

Feeding: Feed mainly on invertebrates including zooplankton, crustaceans and snails, also other fishes and fish eggs.

References:

Groot, C and Margolis, L. Eds. 1991. Pacific Salmon Life Histories. UBC Press. Vancouver, B.C.

Juvenile fish id key. 1995. The Streamkeepers Handbook: a Practical Guide to Stream and Wetland Care. Community Involvement Division, Salmonid Enhancement Program, Department of Fisheries and Oceans. Vancouver, B.C.

Scott, W and Crossman, E. 1973. Freshwater Fishes of Canada. Fisheries Research Board of Canada. Bulletin 184. Ottawa, Ontario.