The Habitat, Movements, and Management of Dolphin, Coryphaena hippurus, in the Western North Atlantic, Caribbean, and Gulf of Mexico

by Farrell, Edward

Dolphin, Coryphaena hippurus, is a highly migratory cosmopolitan pelagic fish that is found seasonally in the Caribbean, Gulf of Mexico, and along the Atlantic coast of the United States. Dolphin are considered as one unit stock throughout the study area. This study used release-recapture data from a long-term tagging project to investigate baseline environmental preferences, habitat suitability based on dynamic ecogeographical variables, spatio-temporal movement through marine cadastral zones, and related policy implications. The data was collected from hundreds of recreational fishermen that tagged dolphin and also recaptured dolphin. A combination of in situ observations from recreational taggers and remotely sampled physical and biological variables (depth, bathymetric slope, distance to shore, distance to continental shelf, sea surface temperature, and sea surface chlorophyll-a) were used to establish an updated and novel baseline of environmental characteristics. A presence-only spatially explicit multivariate modeling approach was used to reveal the bio-physical seasonal preferences of dolphin that define the ecological niche. The results of the models show strong spatial sensitivity to sea surface temperature and surface chlorophyll-a concentration. The tagrecapture analysis showed that dolphin are capable of crossing multiple national and international marine jurisdictional zones throughout their lives. These movements bring the current management insufficiencies to light. Recommendations based on this multifaceted analysis focus on horizontal domestic and international fisheries integration.