Jennifer Doerr

2015

2016

2017

The queen conch, Strombus gigas, is a highly valued marine resource throughout the Caribbean, but habitat degradation and overfishing have caused steep reductions in population numbers. Wild populations of conch have been slow to recover in spite of drastic management measures (e.g., complete fishery closures, shortened harvest seasons, size restrictions). In our previous surveys around St. Croix we found higher overall densities of conch outside Buck Island Reef National Monument (BIRNM) boundaries, in areas open to fishing. However, this was because juvenile densities were highest in these open areas, and overshadowed adult densities, which were actually highest within BIRNM. Whether this is governed by fishing pressure or habitat availability is not certain. We will use acoustic tagging and tracking to determine movement patterns of conch between the management zones of the northern shelf of St. Croix (BIRNM – no-take marine reserve, St. Croix East End Marine Park – zoned-use territorial waters, and open fishing areas). Our research objectives are to examine time spent in protected areas and migration to open fishing areas, and to identify spawning grounds and nursery habitats inside and outside of existing MPA boundaries.The National Park Service initiated this project to evaluate the ecological connectivity between marine reserves around St. Croix and between the reserves and surrounding areas. Their goals include documenting the habitat condition and recovery of depleted fisheries in BIRNM, testing the long-term effectiveness of the marine reserve, and identifying the marine resource connectivity between the adjoining zones of the St. Croix EEMP and Lang Bank. The queen conch portion of the tagging project will support NPS goals by locating critical spawning grounds and documenting migration patterns in relation to existing reserve boundaries. Data obtained from the acoustic tracking component will provide information on resource connectivity by determining if and when conch move between management zones, most importantly into the open fishing areas between no-take zones, and the frequency of these movements. The NPS is particularly interested in determining if juvenile conch from the inshore EEMP migrate further offshore into the BIRNM once they mature. We plan to address this question and our project objectives by deploying acoustic tags on 20 conch in 2017. This project is part of a larger effort coordinated by the NPS involving multiple partners. The USGS has deployed 22 underwater acoustic receivers and is tagging and tracking movements of sea turtles within BIRNM. We have contributed 18 receivers to the effort and researchers from the Massachusetts Division of Fish and Wildlife and The Nature Conservancy (former collaborators from St. John) will deploy 21 receivers and implant acoustic tags in sharks. NOAA’s Center for Coastal and Marine Assessment Biogeography Branch has committed 40 acoustic receivers and is tagging reef fish. The NPS is performing periodic data downloads and receiver maintenance as well as contributing to tagging efforts.

Data from this project will contribute to the understanding of the efficacy of the marine reserve system around St. Croix. Through this project we expect to be able to describe the movement and distribution of queen conch in and around the BIRNM and St. Croix EEMP, including residence times and utilization of habitats in the different management zones. Queen conch populations are considered depleted and are currently managed with size limits, bag limits, annual catch quotas, and seasonal closures during spawning. Little evidence of success exists with these measures. We expect that results from this project will contribute to the conservation and recovery of this species in the region. Federal and territorial managers will be able to use our results to understand the connectivity between marine reserves and thus refine management strategies for each.

• U.S. Virgin Islands

• St. Croix East End Marine Park

Fishing

Ongoing

Funding Ended

https://www.coris.noaa.gov/search/rest/find/document?searchText=projectNumber%3A1100%20OR%20projectTitle%3A"Assessing%20performance%20and%20connectivity%20of%20St.%20Croix%20MPAs"&start=1&max=10&f=searchPage