Bottom Whitefish

Distinguished by the gill rakers that are longer than 20% of the interorbital width, 19 to 25 gill rakers (with modal counts of 22 or 23), and a pronounced hump behind the head in adults (Ref. 27547). Adipose fin well developed, often larger in males; axillary process present in pelvic fins (Ref. 27547). Dark brown to midnight blue above fading to silver on sides and wide beneath; no parr marks in young (Ref. 27547).

Upstream spawning migrations may be extensive but some populations seldom venture far upstream and still others may never go to sea at all (Ref. 593). Mature adults migrate upstream as early as June to spawn in October. It is assumed that the young hatch in late winter and spring, subsequently moving downstream, to return as mature adults 4 to 6 years later (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 - 13; Analspines: 0; Analsoft rays: 10 - 14; Vertebrae: 58 - 63

Feeds on worms, mollusks and crustaceans.

Inhabits coastal waters near shore (Ref. 5723), lower reaches of rivers with slow current, large lakes with tributaries, floodplain lakes, deltas and estuaries, brackish waters (Ref. 59043). Migrates up to more than 1,200 km inland for spawning (Ref. 5723). Overwinters near river mouths (Ref. 5723). There are non-migratory freshwater populations. Adults feed mostly on mollusks, crustaceans and chironomid larvae (Ref. 28219).

fisheries: commercial; aquaculture: commercial