Abstract
Marine fish communities have declined over time in the U.S. Virgin Islands due to habitat degradation and overexploitation, leading management to take multiple approaches such as no-take zones, size limits, and increased monitoring and enforcement. The National Park Services (NPS) monitoring methods switched to RVC protocols in 2017 and continued until 2019. Using this new sampling method has allowed an up-to-date snapshot of fish stocks in both St. Thomas/St. John and St. Croix. Using these data, this report strives to display recent changes in the reef fish populations of the U.S. Virgin Islands across a variety of managed areas. We examined eight species of economically and ecologically important fishes using data from sites within and outside of managed zones: Buck Island Reef National Monument (BUIS), Salt River Bay National Historical Park and Ecological Preserve (SARI), and Virgin Islands National Park (VIIS). The eight species analyzed included: Coney (Cephalopholis fulva), Red Hind (Epinephelus guttatus), Yellowtail Snapper (Ocyurus chrysurus), French Grunt (Haemulon flavolineatum), Foureye Butterflyfish (Chaetodon capistratus), Stoplight Parrotfish (Sparisoma viride), Queen Triggerfish (Balistes vetula), and Blue Tang (Acanthurus coeruleus). These species were further analyzed by examining their length frequencies in protected and unprotected zones. Overall, it was found that the U.S. Virgin Islands is complex in its fish community structures, herbivorous/non-fishery targeted species had higher densities in protected areas and predatory/targeted species had higher densities in open areas. Species’ length frequency graphs were subject to variation depending on each species in terms of their largest individuals. Results seemed to be equivale. The reason for the difference in protected versus unprotected cannot be explained solely by density and length frequency. Instead, we conclude it is caused by a combination of several other factors including inherent reef differences, ecological shifts, and the combination of enforcement/management in the region. This study considers those aspects, and explains the need for re-evaluation and the demand for the implementation of regulations in management zones. Similarly, managers need to reflect of species importance for the ecology of the fish communities.