Comparison of trap and underwater video gears for indexing reef fish presence and abundance in the southeast United States

It is challenging to manage reef fish species in the Southeast U.S. Continental Shelf Large Marine Ecosystem (SUSLME) due to life history strategies that make them vulnerable to overexploitation, difficulty of sampling reef fish in high-relief hard bottom habitats, and fluctuations in utility of fishery-dependent data. In response to declines in fishery-dependent data due to fishery closures, fishery-independent sampling of reef fish has become even more critical to stock assessment. Here we test whether a long-term chevron trapping survey could benefit from the addition of underwater video cameras. Sampling occurred on continental shelf and shelf break habitats (15-83 m deep) between northern Georgia and central Florida. Reef fish frequency of occurrence was significantly higher on video compared to traps for 11 of 15 species analyzed, and the increase ranged from 38% to infinity for these 11 species. Frequency of occurrence for the four remaining species was not significantly different between traps and video. Although positive relationships were observed between log-transformed trap and video indices of abundance for five selected reef fish species, considerable amounts of unexplained variation existed and the relationship for three species was nonlinear. Underwater video can be a beneficial addition to a long-term trapping survey by increasing the frequency of occurrence for most reef fish species, which should translate into improved indices of reef fish abundance in the SUSLME.