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Razor Clam
Generalized life cycle of the razor clam: Male and female clams spawn in late May and June at Long Beach and in July and early August in Queen Charlotte Islands. Mass fertilization occurs in water column. Fertilized eggs develop into ciliated, motile larvae within 12 h of fertilization. Larval phase includes several stages (i.e. trochophore, veliger and umbone) and lasts for about 3-4 weeks, during which time the larvae drift in the plankton and are dispersed by water currents. The larval phase ends when larvae settle from the plankton and attach themselves to sand or broken shell by byssal threads, referred to as spatting. At about 5 mm the spat or juvenile clam burrows into sand, but no permanent burrow can be constructed due to instability of sand. Recruitment of juvenile clams has occurred at low levels in Queen Charlotte beaches since 1971. Adult clams may live to over 10 years and reach a maximum shell length of 18 cm.