Artículo Científico

URI permanente para esta colecciónhttp://10.0.96.45:4000/handle/11056/15075

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Relationship between vegetation cover and feeding areas of jaguars (Panthera onca) on sea turtles in Santa Rosa National Park, Costa Rica
(ELSEVIER, 2019-10-15) Morera Chacón, Brayan H.; Posadas García, Ana C.; Mora Benavides, José Manuel; Carrillo, Eduardo
Several factors determine the distribution of areas in which jaguars feed on sea turtles. Different studies have evaluated the relationship of feeding sites with the distribution of human activity on the beach, distribution of nesting female turtles, interactions and territorial behaviors among jaguars and scavenger's presence. However, no study has evaluated the relationship of jaguar feeding areas with vegetation cover. We calculate de density of sea turtle's carcasses in plots demarked in Nancite beach at Santa Rosa National Park, Costa Rica. The average of carcasses density was 33.79/ha (CI 95% = 19.12–48.46) and the average percentage of vegetation cover was 55.62% (CI 95% = 41.84–69.41). We found a positive relationship between density of carcasses and percentage of vegetation cover. The variation in the density of carcasses was explained in a 21.4% by the vegetation cover. The vegetation cover contributes to the complex nature of food webs, and describing the relationships of this with food webs can provide relevant information for the design of future studies, wildlife management and conservation.
Soundscape structure in forests surrounded by protected and productive areas in central Costa Rica
(Universidad Nacional, Costa Rica, 2023-03-09) Retamosa Izaguirre, Monica; Barrantes Madrigal, Jimy
Ecosystems are under a multitude of pressures, including land-use change, overexploitation, pollution, and climate change. Most studies, resources, and conservation efforts are allocated to protected areas, while anthropogenic activities in their surroundings may affect them in ways that are poorly understood. We evaluated soundscape structure in forests surrounded by protected or productive areas in central Costa Rica. We sampled soundscapes in 91 recording sites in Grecia Forest Reserve and Poas Volcano National Park, and surrounding areas with productive activities (predominantly agricultural and urban). We classified sampling sites into three clusters according to landscape entropy, forest amount, and fragmentation surrounding recording points: more fragmented, more conserved, and intermediate. The conserved cluster showed higher acoustic diversity or entropy, but lower acoustic complexity, shorter duration of sounds in all frequency ranges, and lower amount of energy in the biological frequency bands than the fragmented cluster. We additionally found a positive significant relationship between the amount of forest and acoustic entropy or diversity indices, but a negative relationship with acoustic activity or energy indices. Indices, such as spectral and temporal entropy, the entropy of spectral variance, and total entropy, seemed to be a better fit than acoustic complexity and bioacoustic indices as indicators of habitat conservation in this study. Acoustic indices revealed that the surrounding matrices of protected areas have an impact on acoustic environments. We encourage researchers and decision-makers to carefully interpret acoustic indices when evaluating habitats showing a higher value in acoustic energy or activity because this might not necessarily reflect either a high level of biodiversity or habitat conservation. Also, we highlight the importance of preserving undisturbed forested matrices around protected areas, as they are important for maintaining acoustic diversity.
Surplus killing of olive ridley (Lepidochelys olivace) by jaguar (Panthera onca) in Santa Rosa National Park, Costa Rica
(ELSEVIER, 2022-08-30) Chopin Rodríguez, José M.; Montalvo, Víctor H; Lloyd, Kevin J.; Saénz Bolaños, Carolina; Cruz Díaz, Juan C.; Carrillo, Eduardo
Surplus killing is a rare behavior in large predators and its documentation has been scarce. This phenomenon has been observed mostly in carnivores and comprises on the predation of several prey in a short period that eventually would not be consumed, this behavior presents a challenge to ecological theory because it appears to be a waste of energy. Although there are several records of surplus killing behavior for the Panthera genus, this behavior has not been reported on free roaming jaguar (Panthera onca) populations. Hence, this report describes in-situ evidence of surplus killing by jaguars during the arribada massive nesting on olive ridleys (Lepidochelys olivacea) in Nancite beach, Santa Rosa National Park, Costa Rica. This new report has interesting implications for food web theory, as it shows that under certain circumstances some predators are capable of killing more prey than they can consume, showing how strong the hunting instinct can be for certain species.

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Examinando Artículo Científico por browse.metadata.procedence "Instituto Internacional en Conservación y Manejo de Vida Silvestre (ICOMVIS)"