Feeding Ecology of Great Barracuda (Sphyraena barracuda) in South Florida

Great barracuda ( Sphyraena barracuda ) are a large predatory species that is frequently caught by fishermen off of South Florida. This species exhibits an ontogenetic shift in habitat moving from seagrass and mangrove areas as juveniles to offshore reefs and wrecks as adults. The food habits of great barracuda were investigated by analyzing the stomachs of both juveniles and adults. Fish were obtained by several different fishing methods, including hook-and-line fishing, spearfishing and a seine net. Barracuda were also donated by local fishermen and charter boat captains. Index of relative importance (IRI) was used to compare food types across size ranges. A high percentage of the stomach analyzed throughout this study were empty. As of January 2014, 251 barracuda have been analyzed, with 67 (27%) being adults. Of all 251 fish analyzed, only 55 had identifiable prey items in their stomachs. Preliminary results show that barracuda caught in the juvenile habitat fed primarily on killifish (Cyprinodontidae) and penaeid shrimp. Results with juveniles show that they were able to feed on a variety of prey items without being dependent on one particular food source. Although previous work has shown that juvenile barracuda were almost entirely piscivorous, our preliminary work has shown that penaeids play a major part (%) in their diet as well. Further research is needed to establish any seasonal trends in the adult barracuda diet. This study will provide valuable information about the feeding ecology of barracuda off South Florida, which could lead to better conservation of the species.