Manta season comes to an end in Costa Rica

CREMA is proud to announce that our 2023 manta season (January – May) has come to an end, with the successful tagging of 14 manta rays with acoustic transmitters in the Cabo Blanco Absolute Nature Reserve, where we are describing the existence of a new aggregation site and cleaning station for oceanic mantas. Since this manta ray monitoring project initiated in 2018, we have deployed 37 acoustic tags! Furthermore, throughout 2023 we extended our network of acoustic receivers to the Caño Island Biological Reserve, the Catalina Islands (unprotected) and Bajo Negro (Guanacaste National Park), sites where manta ray aggregations are also known to occur. Finally, we keep a photographic record of every manta possible, as reliable individual ID is possible by studying the unique markings on their bellies.

The use of acoustic tags has allowed us to determine that manta rays visit the cleaning station in Cabo Blanco between 11 am and 4 pm. April has been determined to be the month with peak activity. So far, we have detected the movements of manta rays tagged in Cabo Blanco to all the aforementioned sites , including Cocos Island National Park. Since April of 2022 we have also deployed three satellite transmitters. Two of these mantas moved north to waters several hundred kilometers in front of the coast of El Salvador, while one manta stayed in the nearby waters of the Gulf of Nicoya.

Photo identification is a very useful tool that has allowed us to identify more than 100 individuals along the Pacific coast of Costa Rica over the last 3 year. Photo ID for instance, has allowed us to estimate that the population of mantas in Costa Rica is 66% female.

Despite their high ecological value, manta rays have been subjected to fishing pressure in many parts of the world, either for domestic use of meat or the extraction of their gill rakers to supply traditional oriental medicine. Manta rays are also caught incidentally in different fishing gear, causing injuries that can end in amputation of parts of your body.

Understanding the movements of manta rays would allow us to propose better management

measures for the species. We now better understand the movements of these animals and the biological connectivity among the different aggregations sits, providing insight into the most critical habitats in need of strict protection.

The establishment of management measures that allow us to enjoy these wonderful animals, will safeguard essential ecosystem processes for humanity, and at the same time generate millions of dollars in annual by providing the non-consumptive use of manta rays as an economic option to coastal communities.