Effect of traditional livestock grazing on abundance of small mammals and activity of mountain vizcacha in the high central semi-arid Andes

Abstract

Livestock grazing is common and widespread in the high Andean region; however, few studies have evaluated the effects of traditional camelid grazing (llamas and alpacas) on small and medium sized mammals. We studied small mammals in Sajama National Park in Bolivia. We evaluated the association between livestock abundance and 1) the abundance of small mammals, and 2) small mammal activity patterns. In a grid of 36 sampling stations, small mammals were divided into two study groups, according to their body size and the trophic group. We assessed small mammal abundances with grids of live capture traps and vizcacha with camera traps. We performed GLM and Basic Kernel Density estimation analyses for associations between livestock abundance and abundance of small mammals, and small mammal activity patterns, respectively. The presence of mountain vizcacha and rodents was less likely where livestock abundance was higher. Herbivores and granivores, but not omnivores, were also negatively affected by higher livestock abundance. The diurnal activity patterns of mountain vizcachas declined when livestock abundance was higher. We suggest some alternatives for livestock management plans to minimize the negative effects of traditional livestock on small mammals.