COMMERCIAL HARVEST AND POPULATION STRUCTURE OF A NORTHERN QUAHOG (MERCENARIA MERCENARIA LINNAEUS 1758) POPULATION IN ST. MARY'S BAY, NOVA SCOTIA, CANADA

Innovative Fishery Products Inc. (IFP) has managed a 1682-ha northern quahog (Mercenaria mercenaria) lease in St. Mary's Bay, Nova Scotia, Canada, since 1997. This study describes the commercial harvest and age structure of the northern quahog population from St. Mary's Bay and provides estimates of total mortality and exploitation rates for the lease area. Overall, mean densities ranged from 48.3–88.4 individuals/m2 for surveys conducted in June 2001 and 2002, and in May 2003. Catch and effort in the fishery increased from 1999 to 2001. The mean age to market was 7 y. Recruitment of spat (SL 60 mm or >8 y old) was low. Catch curve analyses resulted in a high estimate of total mortality (Z) for quahogs of ages 7–10. Commercial exploitation only represented 5% to 10% of the estimated standing stock of commercial size quah...