ABSTRACT
Large terrestrial carnivores have undergone some of the largest population declines and range reductions of any species, which is of concern as they can have large effects on ecosystem dynamics and function.1-4 The jaguar (Panthera onca) is the apex predator throughout the majority of the Neotropics; however, its distribution has been reduced by >50% and it survives in increasingly isolated populations.5 Consequently, the range-wide management of the jaguar depends upon maintaining core populations connected through multi-national, transboundary cooperation, which requires understanding the movement ecology and space use of jaguars throughout their range.6-8 Using GPS telemetry data for 111 jaguars from 13 ecoregions within the four biomes that constitute the majority of jaguar habitat, we examined the landscape-level environmental and anthropogenic factors related to jaguar home range size and movement parameters. Home range size decreased with increasing net productivity and forest cover and increased with increasing road density. Speed decreased with increasing forest cover with no sexual differences, while males had more directional movements, but tortuosity in movements was not related to any landscape factors. We demonstrated a synergistic relationship between landscape-scale environmental and anthropogenic factors and jaguars' spatial needs, which has applications to the conservation strategy for the species throughout the Neotropics. Using large-scale collaboration, we overcame limitations from small sample sizes typical in large carnivore research to provide a mechanism to evaluate habitat quality for jaguars and an inferential modeling framework adaptable to the conservation of other large terrestrial carnivores.
Subject(s)
Anthropogenic Effects , Motor Activity , Panthera , Spatial Behavior , Animals , Conservation of Natural Resources , Ecology , Ecosystem , MaleABSTRACT
Abstract Segregation of daily activity patterns is considered an important mechanism facilitating the coexistance of competing species. Here, we evaluated if temporal separation existed among jaguar (Panthera onca), puma (Puma concolor) and ocelot (Leopardus pardalis) and if their activity patterns were related to that of a particular prey. We used camera trap records to estimate the activity schedules of these predators and their prey. We used the coefficient of overlapping (Δ; ranging from 0 to 1) to quantify the temporal interactions between predators and prey, and calculated confidence intervals from bootstrap samples. Strong temporal overlap occurred among the three felids (Δ = 0.63 - 0.82) in both dry and rainforests. However, a greater temporal separation was observed between the closest competitors (jaguar and puma, puma and ocelot). Jaguar and puma had a strong temporal overlap with medium and large-sized prey, while ocelots' activity matched that of smallsized prey. High overlapping coefficients among the felids suggest that temporal segregation is not the main mechanism facilitating their coexistence in these areas. However, fine-scale or spatiotemporal differences in their activity patterns might contribute to their coexistence in tropical environments.(AU)
Resumen La segregación de los patrones de actividad diaria es considerado un importante mecanismo para la coexistencia de especies competidoras. En este estudio, evaluamos si existía separación temporal entre el jaguar (Panthera onca), puma (Puma concolor) y ocelote (Leopardus pardalis), y si sus patrones de actividad se relacionaban con los de sus presas potenciales. Utilizamos registros de cámaras trampa para estimar los patrones de actividad de los felinos y sus presas. Usamos el coeficiente de traslape (Δ; de 0 a 1) para cuantificar las interacciones temporales entre depredadores y presas y calculamos los intervalos de confianza mediante bootstrapping. Observamos un fuerte traslape temporal (Δ= 0.63-0.82) entre los felinos tanto en el bosque seco como en el lluvioso. La mayor segregación temporal ocurrió entre los competidores más cercanos (jaguar y puma, puma y ocelote). El jaguar y el puma tuvieron un fuerte traslape con las presas medianas y grandes, mientras que el ocelote se traslapó con presas más pequeñas. Los altos coeficientes de traslape entre los felinos sugieren que la segregación temporal no es el mecanismo principal de coexistencia en estos sitios. Sin embargo, pequeñas diferencias en los patrones de actividad (e.g. picos de actividad desfasados) podrían contribuir a su coexistencia en ambientes tropicales.(AU)