GROWTH, SPATIAL-DISTRIBUTION, AND ABUNDANCE OF BENTHIC STAGES OF THE SNOW CRAB (CHIONOECETES-OPILIO) IN BONNE BAY, NEWFOUNDLAND, CANADA

The growth and spatial distribution of postlarval snow crab (Chionoece tes opilio) from a relatively unexploitated stock in Bonne Bay, Newfou ndland (Gulf of St. Lawrence), were described from the analysis of siz e distributions from trawls and a dredge sampled between 1988 and 1993 . Immature crabs molted twice a year for instars I-V and then molted a nnually until females reached a terminal molt at maturity (instar X or XI) and males a juvenile stage (instar VIII). Thereafter, juvenile ma les could molt to another juvenile size, skip a molt, or achieve a ter minal molt at the onset of the morphometric differentiation of their c laws depending on the relative abundance of mature males. The life exp ectancy of females and males was 13 and 19 years, respectively. Males should recruit to the commercial size of 95 mm carapace width at insta r XII, 9 years or more after settlement. Relative abundance of early b enthic to commercial-size individuals suggests that small immature cra bs (instar V) migrate from shallow rocky to deep muddy bottoms. The pa tchy spatial distribution observed for the snow crab appeared to be de termined more by substrate and intraspecific factors than by depth. Se asonal movements to shallow waters by larger animals was related to de nsity-and temperature-dependent factors associated with the reproducti ve and growth cycle.