長頜北鮭

Distinguished by its large mouth, the protruding lower jaw, and the presence of only 13 to 17 gill rakers on the lower limb of the first gill arch (Ref. 27547). Dorsal fin high and pointed; pelvic fins with well developed axillary process (Ref. 27547). Generally silvery, with the back usually rather green, blue or pale brown; silvery white below; dorsal and caudal fins have dusky margins, other fins pale (Ref. 27547).

Upstream migration from wintering areas begins at ice break-up. Early upstream movement may be associated with feeding, but movement soon becomes a definite migration to the spawning area. Spawning begins at dusk, and continuing well into the night. A female accompanied by a male, swims to the surface near the upstream end of the spawning ground. She rapidly moves across the current, extruding her eggs. The male, stays below the female so that as the eggs sink, sperm released, fertilizes the eggs. After completing a spawning pass, the female drifts downstream. She may repeat the spawning act over the downstream portion of the spawning area or may move upstream to the head of the grounds before releasing more eggs. Following spawning, there is a fairly rapid downstream migration to wintering grounds (Ref. 27547). It is not certain if spawning occurs annually or at longer intervals (Ref. 27547). Russian fish appear to spawn only every third or fourth year (Ref. 28219). Spawning frequency at Selawik, Alaska may be every other year (Ref. 27547).

Anadromous. Fish that ascend rivers to spawn, as salmon and hilsa do. Sub-division of diadromous. Migrations should be cyclical and predictable and cover more than 100 km.

Dorsal spines (total): 0; Dorsal soft rays (total): 11 - 19; Analspines: 0; Analsoft rays: 14 - 19; Vertebrae: 63 - 69

Occurs in coastal brackish waters near mouths of rivers, but usually in rivers or some land-locked lakes (Ref. 4779). Nerito-pelagic (Ref. 58426). Adults feed mostly on small fishes; young eat aquatic insect larvae and planktonic crustaceans (Ref. 4779). Adults are found in upper reaches of rivers while young ones are in lower reaches (Ref. 45563).

Nerito-pelagic (Ref. 58426). Occurs in coastal brackish waters near mouths of rivers, but usually in rivers or some land-locked lakes (Ref. 4779). At the sea, it is found throughout basin in pelagic zone with temperatures below 18° C and 20-50 m deep (Ref. 59043). Juveniles and adult overwinter and forage at the sea. Encountered in large lowland rivers during migration (Ref. 59043). Adults feed mostly on small fishes; young eat aquatic insect larvae and planktonic crustaceans (Ref. 4779). During spawning migration, it feeds little if at all (Ref. 27547). Spawns on gravel shallows (Ref. 59043). Flesh is white, sweet and slightly oily (Ref. 27547). Sold fresh or frozen.

fisheries: minor commercial; aquaculture: commercial; gamefish: yes; price category: very high; price reliability: very questionable: based on ex-vessel price for species in this family