Chinook salmon
Scientific Name: Oncorhynchus tshawytscha
"Oncorhynchus" means hooked snout in Latin; "tshawytscha" is a West Coast First Nations name for this species.
Chinook are a popular native sport fish along the Pacific Coast of Canada. Although attempts to introduce them to the Great Lakes extend back to 1873, introductions in the late 60’s and early 70's, and continued stocking, have helped control baitfish populations and provided a thriving sport fishery, particularly in Lake Ontario.
Description
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Chinook salmon, courtesy U.S.F.W.S.; public domain |
- Back is blue or green; sides are silvery; belly is white; breeding fish are olive-brown to purple, males darker with hooked jaw
- Black mouth and gums
- Tail entirely spotted
- Short, narrow caudal peduncle (tail)
- Has small adipose fin between dorsal fin and tail, typical of fish in the salmon family
- Leading anal fin ray extends 1/3 the length of the fin
- Jaw extends past eye in adults
- Caudal fin is shallowly forked
Similar To
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| Angler with Chinook salmon on the bank of the stream in which the fish was caught. Note the black mouth and the jaw extending past the eye. Photo credit: Iain Rayner |
- pink salmon
- brown trout
- Atlantic salmon
- Coho salmon
- rainbow trout (Great Lakes)
Key Identifying Features
- Black mouth and gums
- Tail entirely spotted
- Caudal fin shallowly forked
- Mouth extends past eye
Size
- Average length range in Great Lakes: 30-100 centimetres (12-39 inches); typical weight: 3.1–6.8 kilograms (7-15 pounds)
- Ontario record: weight – 21 kilograms (46.4 pounds), length – 119.4 cm (47 in.), Lake Ontario
Distribution and Habitat
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Ontario range of Chinook salmon; modified from Mandrak and Crossman, 1992 |
- Pacific Ocean off northwest coast of North America; young and spawning adults in adjacent rivers and tributary streams
- In Ontario, cold, deep waters of Great Lakes; young in tributary streams and rivers; adults enter streams to spawn in the fall
- Considered a coldwater fish, preferring temperatures of 12-14 ºC (53-57 ºF)
Food
- Juveniles: insect larvae, insects, and other invertebrates
- Adults: primarily smaller fish such as alewife, cisco and rainbow smelt
Predators
- On young: larger fish, including trout and salmon; kingfisher, osprey
- On adults: bears (spawning fish)
- Numerous parasites, including sea lamprey
- Humans
Reproduction
- Reproduce generally at 3 to 5 years old
- Spawn over gravel in rivers and headwater streams, deeper than other salmon; occasionally
over rocky, lakeshore reefs - Females create nests (redds), fanning the bottom clean of silt and digging up to 0.3 m
into the gravel - Spawning temperature is usually between 5.6-12.8 ºC (42-55 ºF); spawning at higher
temperatures has been observed in Ontario - Several males will mate with a singe female
- When spawning is done, the female covers the nest with gravel
- No parental care is given
- Spawning fish die after mating
- Eggs overwinter five to six months before hatching; young Chinook migrate to the lakes
by June, avoiding warmer summer stream temperatures - There is now natural reproduction in all Great Lakes, and it is significant in Lakes Huron
and Ontario - Hatchery stock are used to supplement natural reproduction and support the sport fishery
Management Tips
- Continue to control sea lamprey in the Great Lakes
- Ensure that fishing limits and opportunities are in line with populations; respect
fishing regulations - Where possible, emphasize growth of naturalized populations rather than stocking
- Protect habitat and habitat quality
- Protect and rehabilitate riparian zones to prevent erosion, pollutant run-off and
increased water temperatures - Use "best management practices" with respect to urban and rural development, agriculture, forestry and other industry
- Reduce hard surfaces such as concrete near water bodies that results in higher water
run-off temperatures - Ensure that septic systems are working properly
- Reduce greenhouse gas emissions driving climate change which contribute to increased
water temperatures - Collect long-term data to help monitor the health of aquatic communities, and identify
and address problems
