Influence of Forest Cover and Human Activity on the Distribution of Sites Where Jaguars (Panthera onca) Feed on Sea Turtles in Santa Rosa National Park, Costa Rica

Predation of sea turtles by jaguars (Panthera onca) in the Santa Rosa National Park (SRNP) has been well documented over the past decade. However, the factors that influence jaguar feeding behavior, including environmental factors or characteristics of the beaches and the adjacent forest, are poorly known. This study aimed to identify the relationship between vegetation density and human activity on the distribution of feeding sites of jaguar on sea turtles at nesting beaches in Santa Rosa National Park, Costa Rica. We sampled three beaches (Naranjo, Nancite, and Colorada), where we identified and registered sea turtle carcasses preyed on by jaguars between June and November 2019. Through systematic searches of the forest adjacent to the beach, we documented the species, geographic coordinates, carcass length and width, vegetation cover at the carcass site, and the average vegetation coverage corresponding to the date and beach of each sea turtle carcass. In total, we recorded 338 sea turtle carcasses preyed on by jaguars, 156 at Naranjo beach, 103 at Nancite beach, and 89 at Colorada beach. The beach with the highest average density of carcasses was Colorada (8.7 (SD = 5.42)/ha), followed by Nancite (6.06 (SD = 5.58)/ha) and Naranjo (2.64 (SD = 1.79)/ha). The dragging distance from the beach line to sea turtle carcasses was best explained by the interaction of nesting beach and canopy cover at the carcass. Our canopy cover results may reflect that jaguars select sites that better hide their prey, in the same way that green turtles (Chelonia mydas) usually prefer areas with good coverage to nest in, contrasting to the nesting behavior of olive ridleys (Lepidochelys olivacea). On beaches, higher concentrations were observed where there was less human presence and this may reflect both turtle nesting and jaguar predation activity.