If you have been following along the conservation success of the REEF Grouper Moon Project, you know that our team has made great strides for the preservation of Nassau Grouper populations in the Cayman Islands over the last 20 years. Did you know that this project goes beyond conducting research on the iconic Nassau Grouper? The spawning site on Little Cayman, where much of our Grouper Moon work happens, is an important location for more than 20 other species of fish. We're excited to share the results of several studies that were recently conducted on Tiger Grouper and Yellowfin Grouper, two species that also spawn nearby during winter full moons.
Janelle Layton, a graduate student at Oregon State University, presented preliminary findings on early life history of Yellowfin Grouper at the American Fisheries Society Annual Meeting in August. Early life history stages of fish have been shown to be sensitive to environmental changes. As our oceans undergo significant changes, it is important to evaluate how these changes can impact growth and survival of species with commercial and ecological importance, such as Yellowfin Grouper. For the past few years, our Grouper Moon team has been conducting studies with eggs and larvae collected from a Yellowfin Grouper spawning aggregation that is adjacent to the larger Nassau Grouper aggregation. The work has focused on growth and condition of eggs and larvae reared in different water temperatures. This information will help inform future studies to better understand how a warming ocean will affect the species.
Toni Sleugh, a graduate student at Scripps Institution of Oceanography at UC San Diego, recently submitted a paper to the Journal of Fish Biology that presents findings from a study of migratory behavior of aggregating male Tiger Grouper. To track the movements of these fish, we used special underwater devices called hydrophones, which detect and record acoustic tags attached to animals. The hydrophones, which were deployed around Little Cayman, tracked the movements of ten acoustically-tagged male Tiger Grouper over a 13-month period. Based on findings from this study, it appears that Tiger Grouper establish multiple spawning aggregations around Little Cayman. Unlike other large grouper species, male Tiger Grouper attend one or several aggregations near their home territories instead of visiting a single aggregation site. These findings help us better understand the link between spawning populations and regional populations of Tiger Grouper. In the future, this information can be used to develop management plans for this economically and ecologically important species.
Both of these ancillary projects were conducted as part of the larger Grouper Moon Project. This research will enable better conservation, understanding, and management of these important Caribbean reef predators. To find out more, visit www.REEF.org/groupermoonproject.