The biology of lobsters (Homarus Americanus Milne-Edwards) transplanted to St. Michael's Bay, Labrador

Abstract

In 1982, 1983 and 1985 the Newfoundland and Labrador Department of Fisheries transplanted a total of 4484 adult lobsters (Homarus americanus) to St. Michael's Bay, Labrador with the intention of creating a self-propagating population. Studies done during the summers of 1986 to 1988 were designed to assess whether or not the population is propagating and were concentrated on the lobsters of the 1982 and 1985 transplants. -- The 1985 transplants had few molting events to 1987, and no spawning events to 1988. The stress associated with the transplant caused the paucity of molting and the lack of spawning observed in 1986. Low water temperature is thought responsible for prolonging the effects of the initial stresses. The 1982 transplants were undergoing more molting events than expected. Possible reasons for this are suggested. The percentage of females that were potentially ovigerous was high, but the percentage of ovigerous lobsters was low; of the latter, the fecundities tended to be low and embryo development retarded. Low temperature is probably responsible; however, the possibility of other complicating factors is also discussed. -- The potential reproductive output of the St. Michael's Bay lobsters is too low for the population to become self-propagating. This suggests the physiology of Homarus americanus dictates the southerly limit for the species.