Human impacts on Eastern Pacific green turtles in Costa Rica

GABRIELA S. BLANCO; STEPHEN J. MORREALE; ROTNEY PIEDRA; FRANK V. PALADINO; JAMES R. SPOTILA

Beijin, China

Simposio; 3rd International Symposium of Integrative Zoology; 2009

International Society of Zoological Sciences

The Pacific coast of Costa Rica hosts important nesting sites for the endangered green turtle (Chelonia mydas). We studied the nesting of this species, the areas it occupied and its behavior during an inter-nesting period. We observed turtles on the nesting beach and attached ten satellite transmitters to turtles nesting on Playa Nombre de Jesús and Playa Zapotillal. The satellite transmitters were equipped with a data recorder and allowed us to analyze diving behavior. Turtles spent the 14 day inter-nesting interval in the vicinity of the nesting beach (from the Papagayo Gulf to the Tamarindo Bay). Turtles occupied depths between five and 15 m and executed dives that lasted between two and 25 min. Diving profiles obtained for four turtles were characterized by ?U? shaped dives and suggests that the predominant behavior during this interval was resting. Through direct observation we encountered fishing boats using artisanal longlines and gillnets operating in the area and turtles caught on longlines. This population is also threatened by poaching of eggs and uncontrolled tourism activity on nesting beaches. Thus, human activity threatens this turtle both on land and in the water. Conservation of this species will require not only beach patrols to protect nesting turtles and their eggs but water patrols to control unregulated fishing by local people.