Marine reserves for Caribbean spiny lobster: empirical evaluation and theoretical metapopulation recruitment dynamics

Field data on spiny-lobster abundance, habitat quality, and hydrodynamic transport patterns for a reserve (ECLSP) and three exploited sites (CI, EI, LSI) were used to assess reserve success in reducing fishing mortality and increasing theoretical metapopulation recruitment. Fishing mortality was estimated empirically by quantification of lobster density at ECLSP and the three exploited sites before and after the start of the fishing season in two years. Fishing mortality was estimated to be 47-98% lower at the reserve. Using a circulation model, we theoretically assessed effectiveness of ECLSP and nominal reserves at the exploited sites in augmenting recruitment through redistribution of larvae to all sites. Larvae discharged from ECLSP and EI recruited throughout Exuma Sound, whereas those from LSI and CI recruited only to CI and LSI. Hence, only reserves at EI and ECLSP would be suitable for metapopulation recruitment. In selecting an optimal reserve for metapopulation recruitment, use of information on habitat quality or adult density did not yield a higher probability of success than did determining the reserve location by chance. The only successful strategy was one that used information on transport processes. Designation of effective marine reserves therefore requires careful attention to metapopulation dynamics and recruitment processes.