Impact of jaguar Panthera onca (Carnivora: Felidae) predation on marine turtle populations in Tortuguero, Caribbean coast of Costa Rica

Abstract

Abstract: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 coriacea and 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. Rev. Biol. Trop. 63 (3): 815-825. Epub 2015 September 01. Key words:Chelonia mydas, Dermochelys coriacea, Eretmochelys imbricata, marine turtles, Panthera onca, predator-prey interaction, Tortuguero National Park.Predator-prey interactions play a critical role in the dynamics of the ecosystems (Heithaus, Wirsing, Thomson, & Burkholder, 2008). It is well known that predators can have a direct effect on prey due to consumption of prey individuals (Nelson, Matthews, & Rosenheim, 2004;Heithaus et al., 2008). However, predators can also induce behavioral changes in prey which may lead to shift in activity patterns, reduction in foraging time or spatial and temporal redistribution, among others (Nelson et al., 2004;Heithaus et al., 2008, Valeix et al., 2009Fitzpatrick et al., 2012). Nonetheless, the effect of predators on adult marine turtles has been overlooked since this interaction can be difficult to observe and quantify (Heithaus et al., 2007;Hays, 2008;Fitzpatrick et al., 2012;Bornatowski, Heithaus, Batista, & Mascarenhas, 2012). Heithaus et al. (2008) suggested that predators of adult marine turtles can influence turtle population sizes in spite of low predation rates. Pitman and Dutton (2004) predation upon marine turtle populations in the Mediterranean sea is unknown but probably extremely small compared to other sources of mortality (e.g. anthropogenic causes). Ortiz, Plotkin and Owens (1997) indicated that American crocodile (Crocodylus acutus) predation on the olive ridley sea turtles (Lepidochelys olivacea) have little or no effect on the nesting population at Playa Nancite in Costa Rica. They also highlighted that this interaction may enhance the survival of the local population of crocodiles. Heithaus et al. (2007) also emphasized that the loss of marine turtle predators could result in a negative impact in the ecosystem dynamics.Although jaguar (Panthera onca) predati...

Distribution and hotspots of the feeding areas of jaguars on sea turtles at a national park in Costa Rica

“…Therefore, it is expected that the core areas of jaguar activity and its feeding hotspots areas would be located away from infrastructure and human presence (Arroyo-Arce and Salom-Pérez, 2015). For example, in Tortuguero beach the sea turtle feeding hotspots are located in the farther extreme from the Tortuguero village (Veríssimo et al, 2012;Arroyo-Arce and Salom-Pérez, 2015). Similarly, Alfaro et al (2016) recorded that the feeding areas are located far from camping sites (which have the higher tourist concentration).…”

“…Similar results also have been reported in Tortuguero National Park (Veríssimo et al, 2012; Arroyo-Arce and Salom-Pérez, 2015) and in Naranjo beach, Santa Rosa National Park (Alfaro et al, 2016). For jaguars, the three main factors that determine the distribution and hotspots of the feeding areas are: (a) distribution of the human activity along the beach, (b) distribution of the nesting female turtles along the beach, and (c) interactions and territorial behaviors among jaguars (Veríssimo et al, 2012;Arroyo-Arce and Salom-Pérez, 2015;Alfaro et al, 2016). These three factors may act independently or synergistically depending on the particular circumstances for each beach (Veríssimo et al, 2012;Arroyo-Arce and Salom-Pérez, 2015).…”

“…The American crocodile has been recorded preying only on olive ridley sea turtle Lepidochelys olivacea (ESCHSCHOLTZ 1829) (Ortiz et al, 1997). Finally, the jaguar has been recorded killing five species of sea turtles, including green Chelonia mydas (LINNAEUS 1758), olive ridley Lepidochelys olivacea, hawksbill Eretmochelys imbricata (LINNAEUS 1766), loggerhead sea turtle Caretta caretta (LINNAEUS 1758), and leatherback Dermochelys coriacea (VANDELLI 1761) sea turtles (Fretey, 1977;Autar, 1994;Carrillo et al, 1994;Chinchilla, 1997;Tröeng, 2000;Heithaus et al, 2008;Veríssimo et al, 2012;Keeran, 2013;Arroyo-Arce et al, 2014;Cuevas et al, 2014;Arroyo-Arce and Salom-Pérez, 2015;Guilder et al, 2015;Alfaro et al, 2016;Arroyo-Arce et al, 2017).…”

“…However, predation events by American crocodiles on sea turtles are extremely rare in this beach (Ortiz et al, 1997). Sea turtles are important food sources for jaguars because they are easy prey and they represent a big amount of biomass (Veríssimo et al, 2012;Arroyo-Arce and Salom-Pérez, 2015;Guilder et al, 2015). Additionally, they can be key resources when other prey availability is low (Veríssimo et al, 2012).…”

A morphological comparison of jaguars and pumas in southern Mexico

“…For instance, it has been documented that due to the strength of their bite, jaguars can feed on vertebrates with hard skins or very resistant shells, such as crocodiles, turtles or armadillos (Rabinowitz and Nottingham 1986;Emmons 1989;Nuñez et al 2000;Da Silveira et al 2010;Arroyo-Arce and Salom-Pérez 2015;Guilder et al 2015), and the occurrence of this kind of species in jaguar diet is greater than in pumas (Emmons 1987;Taber et al 1997;Nuñez et al 2000;Scognamillo et al 2003;Foster et al 2010).…”