Chinook Salmon of British Columbia, the official name by the American Fisheries Society, is derived from the Indians name that once lived along the Fraser River. In California and Alaskan fisheries the species is commonly referred to as the king salmon. Spring or spring salmon is often applied to the Chinook race which ascends rivers in early to late spring, while one particular race, which enters the Fraser River after the first fall freshets, is referred to as the fall-bright. Another common name, especially in Puget Sound, is blackmouth. Males are termed bucks; females, does or hens; 1 year old mature returning males are called jacks. The scientific name, Oncorynchus, means hooked snout; tshawytscha is the name given to these fish by the people of Kamchatka Peninsula, U.S.S.R.
The Chinook is by far the largest of the five species of Pacific salmon, with recorded weights to over 100 pounds; one specimen tipped the scales at 126 pounds! Average sizes vary geographically, and even from river to river. In general, average weights for California, Oregon, and Washington fish would be somewhere around 18-22 pounds. British Columbia Chinooks average larger sizes with the heaviest specimens coming from Alaskan rivers, and in particular, the Kenai River where 50 and even 60 pounders are not uncommon among sport fishermen’s catches.
Biological Sampling Manual for Salmonids
Chapter 1 – Chinook Salmon (Oncorhynchus tshawytscha)
Spring, king, blackmouth, jacks, Columbia River salmon, Fraser River salmon, quinnat, hookbill, smilie, mild cure, and tyee.
Chinook salmon is the largest of the salmon species. It is noted for the numerous black spots on the back, dorsal fin, and both lobes of the caudal fin. The bases of the teeth are black, and loose conical teeth are present in mature individuals. When the peduncle is grasped, the tail fin rays remain spread and do not collapse easily. Pyloric caecae count is >120. It is interesting to note that chinook salmon have a specific metallic odour, and smaller sized fish have more mucous surrounding the body compared to the other salmonids.
Pre-spawning adults are greenish blue to black on the dorsal surface, frequently with a faint reddish to rusty hue. They have numerous, moderately large, irregular black spots on the back, upper sides, dorsal fin and both lobes of the caudal fin. The bases of the teeth are black. The flesh colour ranges from red to white, occasionally pink, and sometimes mottled red/pink/white.
At spawning time the back and sides become very dark or bright red.
The body is elongate, depth about 4 into standard length, deepest around tip of pectoral fin, and moderately compressed. Head length is about 3.7 into standard length. Mouth is terminal, large, and directed forward. The upper jaw extends beyond the posterior margin of the orbit. Snout is roundly pointed. Teeth in jaws are movable, moderately sharp, and become enlarged and hooked in spawning males. Teeth are also on the mandibles, premaxillaries, maxillaries, palatines, and on the anterior part of the tongue.
The interorbital space is high, wide, convex, rounded, its width about 2.8 into head length. Gill membranes are free of each other and of the isthmus. The first gill arch has from 18 to 30 rough and widely spaced gill rakers. Branchiostegals range from 13 to 19. Caudal peduncle is moderately compressed, its least depth about 12 into standard length. Pyloric caecae range from 140 to 185. Scales are cycloid with 140 to 153 scales in rows above the lateral line, and 130 to 165 on the lateral line canal.
Adipose fin is stout and fleshy. The number of rays in each of the fins are: dorsal, 10-14; anal, 13-19; pectorals, about 14; and, pelvics, about 10 (each of the abdominal fins have a free tipped fleshy appendage above its insertion). The caudal fin is moderately forked and the outer rays are stiff.
In spawning males the upper jaw forms an elongated hooked snout and the teeth are enlarged. In spawning females the upper jaw is not so strongly hooked, except for very large females.
While Chinooks have been successfully transplanted to the Great Lakes, and to New Zealand, the species is native in North America only to waters draining into the Pacific Ocean from central California to Point Hope, Alaska. Southernmost runs once existed as far south as San Diego, California; how- ever, the southern extremes are now the Sacramento-San Joaquin systems. In general, most Pacific Coast rivers have had, still have occasionally, or sustain Chinook runs if they are large enough to provide adequate flows and temperatures and the other environmental conditions important for ascending, spawning, and rearing. Hatchery runs of Chinook also occur in the San Joaquin tributaries: the Mokelumne, Stanislaus, Tuolumne, and Consumes rivers. Many of British Columbia’s, Oregon’s and Washington’s coastal streams carry runs of fall or spring Chinook, sometimes both. Oregon’s heaviest producers are the Rogue, Umpqua, and Columbia rivers. British Columbia’s Frazer river along with many more play host to excellent Chinook runs; Alaska rivers contain not only the largest runs numerically, but the largest fish as well.