ECOLOGICAL DATA
Distribution: sparse along inshore; appears to prefer
lower reaches of large rivers, e.g. Fraser and Skeena.
Habitat: adults spawn in freshwater near rapids or below waterfalls during May
and Jun; eggs adhere to bottom; juveniles may rear in sloughs in estuaries; appears to
reside in turbid, current swept lower reaches of rivers or estuaries, e.g. mouth of
Fraser Main Arm; feeding migration occurs in April in Fraser River, following the eulachon
run; may be a migration downstream to brackish water in Jul and Aug.
Tidal elevation: utilize deeper sections of lower reaches of river, sloughs or
estuaries.
Food: bottom feeder; young-of-the-year feed on chironomids (e.g. Corophium),
oligochaetes, mysids and midge larvae and adults, molluscs and freshwater invertebrates;
adults prey on fish (e.g. spawned-out eulachon, lamprey, sculpins, stickleback),
chironomids and crayfish.
Predators: few due to bony plates; lamprey.
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GROWTH RATE
Slow; 1 yr old 11-37 cm; 30 yr old male is 145 cm and female
183 cm; males sexually mature 11-22 yr and females at 11-34; maximum recorded size is 6.1
m and 816 kg; may live to be over 100 yr.
FISHERY
Small commercial and sport fisheries; 1986 commercial catch was
6 t valued at $12,000.
REFERENCES
Hart, J.L. 1973. Pacific fishes of Canada. Fish. Res. Board
Can. Bull. 180: 83-84.
Lamb, A., and P. Edgell. 1986. Coastal fishes of the Pacific Northwest. Harbour
Publishing, Madeira Park, B.C.: 18-19.
Lane, E.D. 1985. A bibliography on the white sturgeon, Acipenser transmontanus
Richardson, 1836. Can. MS Rep. Fish. Aquat. Sci. 1828: 33 p.
Northcote, T.G. 1974. Biology of the lower Fraser River: a review. Univ. B.C.
Westwater Res. Cen. Tech. Rep. 3: 94 p.
Schreiber, M.R. 1962. Observations on the food habits of juvenile white sturgeon.
Calif. Fish Game 48: 79-80.
Scott, W.B., and E.J. Crossman. 1973. Freshwater fishes of Canada. Fish. Res. Board
Can. Bull. 184: 96-100.
Semakula, S.N., and P.A. Larkin. 1968. Age, food, and yield of the white sturgeon (Acipenser
transmontanus) of the Fraser River, British Columbia. J. Fish. Res. Board Can. 25:
2589-2602.
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