Sea turtle depredation by jaguars at Tortuguero National Park, Costa Rica

Sebastian Troëng, Eddy Rankin, and Alonso Rankin
Caribbean Conservation Corporation, Apdo. Postal 246-2050, San Pedro, Costa Rica

Depredation of green turtles by jaguars in Tortuguero National Park has previously been reported. The scarce published and anecdotal information available indicate that depredation levels until recently have been low. In an effort to quantify jaguar depredation, the number of sea turtles killed by jaguars were recorded during regular track surveys along 30 km of nesting beach in Tortuguero National Park, 1997-1999. Jaguars killed both green turtles (Chelonia mydas) and leatherbacks (Dermochelys coriacea). Jaguars ate only the neck muscle and a part of the internal organs of the turtle; the carapace was always left intact. The number of jaguar-depredated green turtles increased from a minimum of four in 1997 to 25 in 1998 and 22 in 1999. Two leatherbacks killed by jaguars were encountered in 1999. Several factors may be involved in causing the increase in jaguars depredating nesting turtles. The jaguar population may have increased in recent years as a result of protective measures in Tortuguero National Park or by immigration of jaguars from deforested areas in the proximity of the park. The increase in depredation by jaguars might also be attributable to a small number of jaguars developing the habit of depredating turtles, possibly in response to decreasing populations of other prey species. A more detailed study to quantify the number of jaguars and to determine their prey preference is needed to explain the apparent increase in sea turtle depredation.

Area de Conservacion Tortuguero provided the permit for this research. Caribbean Conservation Corporation funded and organized the study. Chuck and Tom Carr, Eduardo Carrillo, Eduardo Chamorro, Kazuo Horikoshi, Cynthia Lagueux, Anne Meylan, Jeanne Mortimer and Larry Ogren provide useful jaguar information. My co-authors Eddy and Alonso Rankin conducted the majority of track surveys. Research assistants during the 1997-1999 turtle programs also helped with track counts.

Abstract of paper presented at 20th International Symposium, 2000