Nearly two decades of adaptive fisheries regulations, including marine protected areas and seasonal closures, in the Cayman Islands have led to a tripling of populations of critically endangered Nassau Grouper on Little Cayman, according to a study. Many reef fish species that come together in large numbers to spawn are at increased risk of overfishing during such aggregations. Lynn Waterhouse, Brice Semmens, and colleagues analyzed data collected from 2005 to 2018 to determine the effect of governmental fishery management on two populations of Nassau grouper in the Cayman Islands whose breeding areas had been closed seasonally or from which the catch had been limited. Early in each spawning season, the authors tagged a small subset of the large reef fish with colored tags. On subsequent dives during the aggregation, divers obtained a census of the proportion of tagged individuals. This data, together with video census data, was used to develop an integrated population model over time. By the end of 2018, the two Nassau Grouper populations had tripled in size. According to the authors, seasonal and spatial closures can lead to conservation success in rebuilding populations of aggregation-based fisheries.
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Article # 19-17132: " Recovery of critically endangered Nassau grouper ( Epinephelus striatus ) in the Cayman Islands following targeted conservation actions," by Lynn Waterhouse et al.
MEDIA CONTACT: Brice Semmens, Scripps Institution of Oceanography, San Diego, CA; tel: 858-822-0518; email: < bsemmens@ucsd.edu >; Lynn Waterhouse, John G. Shedd Aquarium, Chicago, IL; e-mail: < lwaterhouse@sheddaquarium.org >
Proceedings of the National Academy of Sciences