Oncorhynchus clarkii clarkii
• Widely variable colouration and marking patterns
• Very similar to Rainbow Trout at all life stages
• Upper jaw long; extends behind eye when mouth is closed (Rainbow does not)
• Usually has red (rarely yellow) 'cut' marks on underside of gill covers
• Black spots on dorsal fin (Pacific Salmon species have none as juveniles)
|COSEWIC||Species at Risk Act|
|Blue List||Not Assessed||None||G4T4, S3S4|
• Spawn in later winter/early spring; usually peaks in February
• Three general life history types; Resident, Freshwater Migratory and Sea Run
• Many variations of these types within and among populations
• Unlike Pacific Salmon, Cutthroat and Rainbow Trout may spawn in more than one year.
• May mature at very small size; 15 cm in some populations
• Rarely live longer than 5 years
• Some populations in coastal BC are isolated above waterfalls (colonized stream when sea level higher)
• Move between freshwater habitats including streams, large rivers, and lakes.
• Typically larger body size (to 60 cm in some lakes); may live to 10 years
• Spend one to 3 (rarely 4) summers in freshwater before migrating to sea at 25-30 cm in length
• Typically at sea for summer months and in freshwater over winter
• Most mature at age 4.
• Arrive in spawning streams between August and April to spawn in spring.
Smaller juveniles and residents eat zooplankton and aquatic invertebrates
Larger migratory and sea run individuals also consume fish
• Require cool-water (<18 C) • Most spawn in gravels of small, low gradient coastal streams; often <1 m wide • Rearing and foraging habitat is highly variable. • In streams highest densities are in low gradient reaches with extensive pools, gravel substrate and abundant large woody debris • Commonly use off channel habitats of small streams for overwintering
• Entire BC coast including most coastal islands.
• Rarely more than 200 km inland on South coast (Hope, in Fraser system)
• Introduced into Kootenay and Lower Arrow Lakes
• Coastal drainages from Northern California to Prince William Sound, Alaska
• Over 600 sea run stocks in BC
• At least 15 extirpated and 14 at risk in Lower Mainland and Southern Vancouver Island
• Coho stocked in streams tends to displace wild Cutthroat fry and juveniles from preferred habitats
Primary Information Source:
McPhail, J.D. 2007. The Freshwater Fishes of British Columbia. University of Alberta Press. Edmonton, Alberta.