Population parameters of American lobster inside and outside no-take reserves in Bonavista Bay, Newfoundland

Abstract

Marine no-take reserves are being used increasingly to conserve exploited populations and fisheries, but there have been few studies of whether they achieve the goals for which they were created. To determine the potential effectiveness of no-take reserves as a fisheries conservation tool for American lobster ( Homarus americanus), I quantified the consequences to population structures of two small, no-take reserves (Round Island and Duck Islands) in Bonavista Bay, Newfoundland, during 1997–1999. Although this study concerned only the first 3 years following reserve establishment, there were obvious differences in lobster population parameters inside and outside no-take reserves. At the Round Island reserve, population density was high and stable over time, and female and male size increased, as did the proportion of ovigerous females. However, at the Duck Islands reserve, population density increased dramatically between 1997 and 1998, and male size increased over time, but there was no change in female size or in the proportion of ovigerous females. Lobster density, female and male size, and the proportion of ovigerous females were greater within the Round Island reserve compared to an adjacent harvested area. At the Duck Islands, females and males were larger in size within the reserve, but I found no difference in lobster density or the proportion of females that were ovigerous between the reserve and an adjacent harvested area. Taken together, these data suggest that no-take reserves offered increased survival to lobsters (particularly at the Round Island site) and thereby may, over time, provide benefits to the local fishery.