ECOLOGICAL DATA
Distribution: occur only on surf-swept beaches in Long
Beach region on the west coast of Vancouver Island and on beaches east of Masset on the
northeast coast of Graham Island in the Queen Charlotte Islands.
Habitat: sandy, exposed beaches; usually burrows from just below surface to a
depth of 25 cm; can burrow to depths greater than 60 cm in less than a minute; planktonic
larvae dispersed by currents; do not form permanent burrows.
Tidal elevation: mid-tide level to 20 m subtidal depth.
Food: filter feeder; mainly planktonic diatoms, but also zooplankton and
detritus.
Predators: gulls, ducks, crabs and fishes.
GROWTH RATE
Variable, fastest at lower beach levels; sexually mature after
1 yr in south and 3 yr in north; minimum legal size of 90 mm is reached in 1-2 yr at Long
Beach and 3-4 yr on Queen Charlotte Islands; largest and oldest clams found in B.C. are
from Queen Charlotte Islands.
FISHERY
Commercial, native and sport fisheries; accounts for less than
5% (142 t in 1986) of commercial intertidal clam harvest.
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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: 41.
Bourne, N. 1979. Razor clam, Siliqua patula Dixon, breeding and recruitment at
Masset, British Columbia. Proc. Natl. Shellfish. Assoc. 69: 21-29.
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.
Bourne, N., and D.B. Quayle. 1970. Breeding and growth of razor clams in British
Columbia. Fish. Res. Board Can. Tech. Rep. 232: 42 p.
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.
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.
Ricketts, E.F., J. Calvin, and J.W. Hedgpeth. 1985. Between Pacific tides. 5th ed.
Stanford Univ. Press, Stanford, Calif.: 256-257.
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