Movements and diving behavior of internesting green turtles (Chelonia mydas, Linnaeus 1758) along Pacific Costa Rica

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

Integrative Zoology

Blackwell Publishing Asia Pty Ltd and IOZ/CAS

Año: 2013 vol. 8 p. 293 - 306

1749-4877

Using satellite transmitters, we determined the internesting movements, spatial ecology and diving behavior of East Pacific green turtles (Chelonia mydas Linnaeus 1758) nesting on  Nombre de Jesús and Zapotillal beaches along the Pacific coast of north-western Costa Rica.  Kernel density analysis indicated that turtles spent most of their time in a particularly small area in the vicinity of the nesting beaches (50% utilization distribution was an area of 3 km2). Minimum daily distance traveled during a 12-day internesting period was 4.6 ± 3.5 km. Dives were short and primarily occupied the upper 10 m of the water column. Turtles spent most of  their time resting at the surface and conducting U-dives (ranging from 60 to 81% of the total  tracking time involved in those activities). Turtles showed a strong diel pattern, U-dives mainly took place during the day and turtles spent a large amount of time resting at the surface at night. The lack of long-distance movements demonstrated that this area was heavily utilized by turtles during the nesting season and, therefore, was a crucial location for conservation of this highly endangered green turtle population. The unique behavior of these turtles in resting at the surface at night might make them particularly vulnerable to fishing activities near the nesting beaches.