Abundance and Home Range of Great Barracuda Sphyraena barracuda Inhabiting Coastal Waters in the Northern Caribbean

Great barracuda are top predators of tropical marine systems. Given their use of a wide range of habitats, large global distribution and locally high abundances, barracuda can play an important ecological role, yet few studies quantify their spatial ecology. Tracking via passive acoustic telemetry is being conducted in Culebra, Puerto Rico and Buck Island Reef National Monument (BIRNM) in St. Croix, U.S. Virgin Islands. To date, 12 (mean length = 105.5cm, SD = 25cm) and 36 (mean length = 91.7cm, SD = 16.5cm) fish are being monitored in Culebra and St. Croix, respectively. Barracuda were sampled by trolling with heavy action recreational fishing gear and artificial lures. A random survey was undertaken to infer population abundance in the two locations. Randomization tests on the catch per unit effort (CPUE) data were used to compare population densities between sites. Home ranges were estimated using minimum convex polygons (MCP) and kernel density estimators (KDE) in order to compare habitat use as a function of fish size classes and between study sites, as well as to determine whether home range size estimates are consistent across these two commonly used methods. KDEs were also used to model habitat use across each study site.