ECOLOGICAL DATA
Distribution: common in protected beaches in bays and
estuaries along B.C. coast, and near rocky outcrops on outer coast.
Habitat: firm, gravel beaches; often in association with butter clam; burrow to
a maximum depth of 15 cm, but usually 3-8 cm below surface; planktonic larvae dispersed by
currents; adults remain in same burrow for life.
Tidal elevation: slightly above mid-intertidal to subtidal; may occur to 12 m
subtidal depth. Food: suspension feeder; mainly phytoplankton, but also zooplankton
and detritus.
Predators: crabs and fishes prey on juveniles; moon snail, birds, and sea stars
prey on adults.
GROWTH RATE
Slow; sexually mature at 25 mm (about 2 yr.); legal size of 38
mm is reached in 3.5 yr in Strait of Georgia and 5-6 yr in north coast.
FISHERY
Commercial, Native and sport intertidal fisheries; accounts for
about 10% (285 t in 1986) of commercial intertidal clam harvest; sewage and paralytic
shellfish poisoning (PSP) have closed large areas of coast to harvesting.
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REFERENCES
Anon. (no date). Clams of British Columbia. Fish. Oceans Can.,
leaflet: 4 p.
Bernard, F.R. 1983. Catalogue of the living bivalvia of the eastern Pacific Ocean:
Bering Strait to Cape Horn. Can. Spec. Publ. Fish. Aquat. Sci. 61: 52.
Bourne, N. 1984. Clam predation by scoter ducks in the Strait of Georgia, British
Columbia. Can. Tech. Rep. Fish. Aquat. Sci. 1331: 17 p.
Bourne, N. 1986. Intertidal clams, p. 22-31. In G.S. Jamieson and K. Francis
[ed.] Invertebrate and marine plant resources of British Columbia. Can. Spec. Publ. Fish.
Aquat. Sci. 91.
Jamieson, G.S. 1986. Paralytic shellfish poisoning, p. 44-46. In G.S. Jamieson
and K. Francis [ed.] Invertebrate and marine plant resources of British Columbia. Can.
Spec. Publ. Fish. Aquat. Sci. 91.
Kozloff, E.N. 1983. Seashore life of the northern Pacific coast. Douglas &
McIntyre, Vancouver: 292-293.
Quayle, D.B. 1978. The intertidal bivalves of British Columbia. B.C. Prov. Mus. Handb.
17: 63-64.
Quayle, D.B., and N. Bourne. 1972. The clam fisheries of British Columbia. Fish. Res.
Board Can. Bull. 179: 70 p.
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