In recent decades, many shark and ray populations have declined dramatically. In the wider Caribbean, this trend became apparent in the 2000s, when researchers from Dalhousie University used REEF survey data to conduct a regional assessment of reef-associated shark sightings. This publication, published in the journal PLoS ONE, assessed the effects of exploitation on population trends. Now, more than 15 years later, scientists from Scripps Institution of Oceanography are revisiting the same dataset to evaluate sightings of sharks and rays in the REEF Volunteer Fish Survey Project database from 1993 to 2025. Dr. Brendan Talwar will be attending the Joint Meeting of Ichthyologists and Herpetologists later this month to present findings from this analysis, giving a talk titled "Citizen science surveys reveal decades-long trajectories of reef-associated shark and ray sightings in the wider Caribbean"
Dr. Talwar and colleagues have generated decades-long time series of sightings probabilities for the most common shark and ray species across multiple countries, using models that account for variable survey effort across space and time. They also assessed changes in sightings following the establishment of International Shark Sanctuaries, which prohibit shark and/or ray fishing. For many of these nations, the resulting time series provide the first long-term insights into reef-associated shark and ray population trajectories, offering critical information for conservation and management decisions. These findings arrive at a pivotal moment as many countries in the wider Caribbean work to balance fisheries, dive tourism, and conservation, often in the absence of reliable data.
Photo by: Daryl Duda