Each year during the full moon, more than 15,000 Camouflage Grouper, Epinephelus polyphekadion, converge in French Polynesia to spawn in the early morning hours. They are joined by hundreds of sharks, including gray reef sharks, whitetip reef sharks, oceanic blacktip sharks and lemon sharks. The sharks take advantage of this massive gathering of large-bodied grouper to feast on distracted individuals. Divers are very fortunate to witness this spectacular natural event, and last month, REEF volunteer and scientist Tom Sparke joined a team of citizen science divers from Ocean Blue Tree Foundation in Fakarava, French Polynesia, to monitor the Camouflage Grouper spawning aggregation.

The spawning aggregation was a perfect opportunity to collect thousands of images of individual Camouflage Grouper in a very short period of time. Thanks to the generous support of Ocean Blue Tree Foundation, these citizen science divers collected valuable image data, including stereo-video imagery, which will allow for length measurements of the individuals. REEF, as part of the new GrouperSpotter project, will use the images to develop an AI-powered facial recognition platform for this species and other grouper species, allowing individuals to be matched across days, years and locations. This information will improve knowledge of population size and recruitment as well as individual growth, behavior, and mortality.

This project is a collaborative effort between REEF, Scripps Institute of Oceanography, The Semmens Lab at Scripps Institution of Oceanography, Wildme, and Ocean Blue Tree Foundation. Be sure to stay tuned for more information about the GrouperSpotter project!