The jaguar and the puma are sympatric throughout the jaguar’s distribution in the Neotropics. Several studies have been conducted on these two species, but few have examined the ecological interactions between them. Trophic separation has frequently been studied, but only two studies have considered variables other than diet.The goal of this study was to identify the ecological and behavioural factors that mediate the coexistence of jaguar and puma in a mosaic landscape in the Venezuelan llanos. An understanding of these mechanisms is critical to the development of conservation and management plans for these two predators in an areawhere both are threatened by loss of preferred prey and by persecution for depredation on livestock. This study was carried out in the llanos of west-central Venezuela from January 1997 to November 1998. It was a continuation of a study initiated in 1996 by Farrell (Farrell,1999) and for that reason part of her data are included. Hato Pi˜nero, the study site, is located in the southeastern corner of the state of Cojedes (8◦40–9◦00N,68◦00–68◦18W). Pi˜nero’s 80 000 ha support both aworking ranch of 10 000 cattle, and a thriving ecotourism business. Average annual precipitation between 1961 and 1965 was 1469 mm, with 86% of the rain falling between May and October. During the rainy season up to 80% of the ranch is flooded, with water depths ranging from a few cm to 1.5m, and the workable study area is reduced to about 30 000 ha. During the wet season, the average low temperature is 19.8 ◦C, and the average high temperature is 31.8 ◦C. In the dry season, the average low temperature is 17.9 ◦C, and the average high temperature is 34.6 ◦C. The topography on the ranch includes permanentrivers, temporary creeks (semi-permanent, seasonally drying water bodies), grassland or open pasture, savanna woodland, non-flooded evergreen forest and dry forested uplands. The ratio of open to forested areas is roughly 50 : 50. While many of Pi˜nero’s streams are bordered by forests, relatively large areas of semi deciduous forest are not adjacent to streams. In general, the landscape can be characterized as a complexmosaic of interdigitated forests and open areas with vegetation types based on interactions of elevation, substrate and hydrology. Prey diversity and abundance vary greatly across the landscape. Overall, prey diversity declined as elevation increased and was lower in savannas than forests. During the wet season, prey species seemed to become more dispersed within large annual use areas, making use of more dispersed resources, less surfacewater constraints and the phenology of favoured plant foods. Dietary habits of puma and jaguar were determined from scats and kills. Scatswere collected opportunistically from trails and roads and the identity of the predator was assigned by the presence of tracks. Scats were air dried and stored until analysed. Prey contents of the collected scats were visually identified to the lowest taxa possible by examination of teeth and/or hair scale pattern by comparing them to a reference collection. Carcasses of prey animals were located by tracking the radio-tagged cats and from the presence of scavengers and predator sign. If the predatorwas unknown, ancillary evidence such as tracks, scats, teeth marks, type of killing injury, feeding method and caching behaviour was examined to identify the predator involved. Where the identity of the predator that left the scat or made the kill was unknown, these data were excluded from the analysis. In addition to the species of prey killed, records were made of age-class, based on the descriptions given by Ojasti for capybara, and by Dimmick & Pelton for peccary and white-tailed deer.a
Source: Animaldiscovery-chanel,
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