Trophic Dynamics and Feeding Ecology within the Southeast Florida Coastal Pelagic Fish Complex

The trophic interactions and feeding ecology of coastal pelagic fishes remains poorly known. To elucidate these ecological relationships, this study focused on six species: king mackerel, blackfin tuna, skipjack tuna, little tunny, wahoo, and dolphinfish. From March 2010 to March 2012, samples from over 500 fishes were collected opportunistically from recreational anglers in southeast Florida. The stomach, gonads, muscle tissue, and liver tissue were collected from each specimen, as well as length data. Stable isotope analysis of carbon δ13C and δ15N in the muscle tissue was conducted along with descriptions of stomach contents. The combined analyses provide a more complete evaluation of the trophic interactions and positions among the coastal pelagic community. The preliminary analysis of stomach contents and 13C data for blackfin tuna, king mackerel, and little tunny (-16.5 to 20.5) shows a diverse diet of fish, squid, and crustaceans. The 13C and 15N data together indicates differences in trophic position and diet among the species in the coastal pelagic complex.