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Little is known about the effects of jaguars on the population of marine turtles nesting in Tortuguero National Park, Costa Rica. This study assessed jaguar predation impact on three species of marine turtles (Chelonia mydas, Dermochelys coriáceaand Eretmochelys imbricata)that nest in Tortuguero beach. Jaguar predation data was obtained by using two methodologies, literature review (historical records prior the year 2005) and weekly surveys along the 29 km stretch of beach during the period 2005-2013. Our results indicated that jaguar predation has increased from one marine turtle in 1981 to 198 in 2013. Jaguars consumed annually an average of 120 (SD= 45) and 2 (SD= 3) green turtles and leatherbacks in Tortuguero beach, respectively. Based on our results we concluded that jaguars do not represent a threat to the population of green turtles that nest in Tortuguero beach, and it is not the main cause for population decline for leatherbacks and hawksbills. Future research should focus on continuing to monitor this predator-prey relationship as well as the factors that influence it so the proper management decisions can be taken.

Habitat characteristics and human activities are known to play a major role in the occupancy of jaguars Panthera onca across their range, however the key variables influencing jaguar distribution in Tortuguero National Park, Costa Rica, have yet to be identified. This study evaluated jaguar occupancy in Tortuguero National Park and the surrounding area. Jaguar detection/non-detection data was collected using digital camera traps distributed within the boundaries of the protected area. Local community members were also interviewed to determine jaguar occurrence in the Park’s buffer zone. Occupancy models were then applied to identify the habitat characteristics that may better explain jaguar distribution across the study area. From June 2012 to June 2013, a total of 4 339 camera trap days were used to identify 18 individual jaguars inside the protected area; 17 of these jaguars were exclusively detected within the coastal habitat, whilst the remaining individual was detected solely within the interior of the Park. Interviewees reported 61 occasions of jaguar presence inside the buffer zone, between 1995 and 2013, with 80% of these described by the communities of Lomas de Sierpe, Barra de Parismina and La Aurora. These communities also reported the highest levels of livestock predation by jaguars (85% of attacks). In the study area, jaguar occurrence was positively correlated with the seasonal presence of nesting green turtles Chelonia mydas, and negatively correlated with distance to the Park boundary. Our findings suggested that the current occupancy of the jaguar in the study area may be a response to: 1) the vast availability of prey (marine turtles) on Tortuguero beach, 2) the decline of its primary prey species as a result of illegal hunting inside the Park, and 3) the increase in anthropogenic pressures in the Park boundaries. Rev. Biol. Trop. 62 (4): 1449-1458. Epub 2014 December 01.

La Iniciativa del Corredor del Jaguar pretende mantener la conectividad de esta especie. En Costa Rica, esta iniciativa inició en el Subcorredor Biológico Barbilla-Destierro. En este Subcorredor, se ha identificado la pavimentación de un camino de lastre (asociado a las obras de mitigación social del Proyecto Hidroeléctrico Reventazón), como una potencial barrera para la conectividad del jaguar (Panthera onca) y otras especies. Este estudio sugiere un método para identificar los cruces de fauna sobre el camino. Se tomaron datos de junio del 2011 a enero del 2012. Se compararon los registros de avistamientos y atropellos entre una sección de lastre y una de pavimento del mismo camino. Para identificar los pasos de fauna se sobrepusieron distintas fuentes de información: recorridos, entrevistas y conectividad estructural. Al comparar los caminos se encontró que en el pavimento circulan más vehículos, hay más casas, hay más atropellos y se registran menos especies y avistamientos de fauna. Se identificaron tres sitios de cruces de fauna y cinco sectores. Se registró el cruce del camino por jaguar y caucel (Leopardus wiedii) y el uso de una alcantarilla por mapaches (Procyonlotor). Esta metodología puede ser implementada por proyectos viales para identificar los sitios de cruce de fauna y brindar recomendaciones sobre las medidas ambientales de mitigación a implementar asociadas a mejoras o construcción de caminos.