After nesting on Nicaraguan beaches, hawksbill sea turtles visit the brackish waters of mangrove swamps in the internal gulf of Nicoya. The information was confirmed by a group of researchers from the Eastern Pacific Hawksbill Initiative, in collaboration with students from the University of Costa Rica and Costa Rican researchers from the non-governmental organizations Pretoma and Widecast.
The biologists were first alerted by the Nicaraguan organization Paso Pacífico, that a hawksbill turtle that nested at Playa Brasilón, along Nicaragua’s southern Pacific on Aug. 9, 2012, had made its way into Costa Rica’s gulf of Nicoya. Because the Nicaraguan researchers had equipped the turtle with a satellite transmitter, they were able to determine that it had stayed more than 150 days within the mangroves and lagoons surrounding Abangares.
When the researchers inspected the site last Feb. 28, they didn’t only catch an adult hawksbill sea turtle, they also found out that it had nested five times throughout 2012 in Estero Padre Ramos, northern Nicaragua. This was possible because the turtle carried a metal tag on one of its fore flippers, which had been applied by the international organization Flora and Fauna International.
“This discovery highlights the importance of reaching bi-national agreements to guarantee the survival of the hawksbill sea turtle, a critically endangered species,” said Alexander Gaos, director of the Eastern Pacific Hawksbill Initiative. “The species is essential in the maintenance of the marine ecosystem, a function that is extremely important for the coastal communities of both countries, which depend on healthy and productive seas,” pointed out the expert.
For Astrid Sánchez, a member of the Eastern Pacific Hawksbill Initiative and graduate student in tropical coastal area integrated management at the University of Costa Rica, a study of the ecology of the hawksbill’s diet in this area could contribute to the understanding of why adult hawksbills choose mangrove habitats within the gulf of Nicoya. “Because the species is critically endangered in the eastern tropical Pacific, it’s particularly important to identify critical nesting and feeding habitats alike, and work towards the development of the most convenient local and regional management strategies.
Researchers also made note of the presence of numerous boats practicing illegal fishing methods, including drag nets (an artisanal version of a shrimp trawl net) and gill nets with illegal mesh sizes.
“Costa Rica needs to immediately attend to this problem, as it’s evident that illegal overfishing is being done under a veil of absolute impunity,” said Randall Arauz. “If ecosystem based fisheries are not promoted in the Gulf of Nicoya, it will be impossible to reestablish populations of fish that coastal communities depend on, and endangered species like the hawksbill turtle may succumb,” Arauz is with Pretoma, an acronym for the Programa Restauración de Tiburones y Tortugas Marinas.