La Encrucijada Biosphere Reserve (REBIEN) and Puerto Arista Estuarine System (SEPA) are natural protected areas and Ramsar sites in Chiapas, Mexico. In this study, we conducted an inventory of medium-sized and large mammals using camera trapping. We recorded 23 species in the REBIEN and 13 species in the SEPA. In addition, 35% of the species recorded in the two sites are at some category of risk of extinction at the national or international level. The most abundant species in the REBIEN were Northern Raccoon (Procyon lotor (Linnaeus, 1758)) and White-Nosed Coati (Nasua narica (Linnaeus, 1766)). In the SEPA, White-tailed Deer (Odocoileus virginianus (Zimmermann, 1780)), Collared Peccary (Dicotyles crassus (Merrian, 1901)), and White-Nosed Coati (Nasua narica). Our results highlight the importance of both study sites in the conservation of medium-sized and large mammals and underline the urgent need to develop conservation strategies for these areas.

Climatic fluctuations have a biogeochemical effect on food availability and quality, resulting in adjustments of the foraging and food selection behavior of animals. Our study aimed to evaluate the influence of seasonal variation on abundance of food resources and its effect on food selection of Xerospermophilus perotensis, an endemic species of ground squirrel in the Oriental Basin. Food selection behavior was recorded using focal animal and continuous behavior sampling on a squirrel population inhabiting the grassland of a semi-arid area. The results show that their diet consisted of 6 plant species with significant differences in the time spent feeding on each plant species (X 2 = 128.96; P = 0.01). The species with the highest feeding times included Scleropogon brevifolius (63.6 %), Verbena bipinnatifida (10.6 %) and Erigeron pubescens (10.5 %). These plant species had the highest percentage of vegetation cover and availability among seasons, but they were of low nutritional quality with regard to their protein/fiber ratio. However, during specific periods, associated either with gestation and lactation or prior to hibernation, the squirrels increased their protein consumption. This suggests that squirrels are opportunistic feeders, and under certain conditions tend to select plant species that provide them with better quality diets. Las fluctuaciones climáticas tienen un efecto biogeoquímico sobre la calidad y la disponibilidad de los alimentos, lo que resulta en ajustes en la conducta y la selección de los alimentos de los animales. Nuestro objetivo fue evaluar la influencia de la variación estacional en la abundancia de los recursos alimenticios y su efecto sobre la selección de alimentos por Xerospermophilus perotensis, una especie de ardilla endémica de la Cuenca Oriental. La conducta de alimentación se registró utilizando un muestreo animal-focal con registro continuo en una población de ardillas que habita en los pastizales de una zona semiárida. Los resultados mostraron que su dieta consistió en 6 especies de plantas con diferencias significativas en el tiempo de alimentación de cada especie (X 2 = 128.96; P = 0.01). Las especies con los mayores tiempos de alimentación fueron Scleropogon brevifolius (63.6 %), Verbena bipinnatifida (10.6 %) y Erigeron pubescens (10.5 %). Estas especies de plantas tuvieron el mayor porcentaje de cobertura vegetal y disponibilidad entre estaciones, pero fueron de baja calidad nutricional con respecto a su relación proteína / fibra. Sin embargo, durante períodos específicos, asociados con la gestación y la lactancia o antes de la hibernación, las ardillas aumentaron su consumo de proteínas. Esto sugiere que las ardillas son consumidores oportunistas, y bajo ciertas condiciones tienden a seleccionar especies de plantas que les proporcionen dietas de mejor calidad.

Scarcity of information regarding the natural history of Leopardus guigna, an endangered felid native to Chile and western Argentina, hampers the successful implementation of conservation strategies. Very little is known about the movement behavior of L. guigna and home range estimates rest on less than a handful of radiotracking studies. Due to the difficulties inherent in any study requiring the live capture of protected species, we suggest a mathematical approach to the modeling of territories occupied by individual guignas. Our approach is based on the hypothesis that L. guigna maintains a sedentary behavior in a specific area of a given territory, whereby starting points can be derived from point observations. In this context, the present article shows a way to simulate a distribution of points in a territory using random walkers to emulate field data as could be obtained by means of telemetry. Our model allows for an estimation of mean distances covered by individual cats from a fixed starting point and thus enables the prediction of interactions with known threats to the species, such as motor vehicles, free-roaming dogs, and people. The knowledge gained in this process can be of much help when defining the boundaries of protected areas and, more generally, in the planning of infrastructure, rural and urban development.