DNA Barcoding of Fish Eggs in the Gulf of Mexico

DNA barcoding of fish eggs is a relatively new technique that enables more accurate identification of early life stages of ecologically and economically important fish species. Using DNA barcoding of individual planktonic percomorph eggs, this thesis determines putative spawning locations of neritic and oceanic fish species in the Gulf of Mexico (GoM). Surveys at 40 stations in the Gulf of Mexico showed a clear delineation of spawning sites, with neritic fish eggs generally found on continental shelves, and oceanic fish eggs found at the surface of deeper waters. However, samples collected between Florida and Cuba revealed exceptions to this trend driven by physical oceanographic processes, with mesoscale eddies transporting eggs of neritic fishes off the Florida continental shelf into the deep Florida Straits. This thesis highlights new spawning information for many marine species, including numerous economically important species (e.g., tunas, groupers, dolphinfishes, billfishes). Methods developed in this thesis allow new interpretation of the interplay of species life history, hydrodynamics of GoM waters and varying habitats. Better understanding of the distribution of fish eggs can help identify regions where additional protection of spawners and recruits may be appropriate