Multiscale patterns of habitat and space use by the pacarana Dinomys branickii: factors limiting its distribution and abundance
Artículo de revista
The factors that influence habitat and space use by animals, and therefore their distribution and abundance, vary with spatial scale. The pacarana Dinomys branickii is a large rodent of the tropical Andes threatened by illegal hunting and habitat loss. We identified variables related to pacarana habitat use at 4 spatial scales in the Colombian Andes: landscape (3.14 km2 circles), forest patch, foraging area, and den. At the landscape scale, pacaranas used areas with 20 to 95% forest cover that were not different from randomly sampled sites. At the forest fragment scale, used patches (mean = 12 ha) were larger than unused patches, but independent of distance to continuous forest. At the foraging area scale, habitat use was related to the presence of rocky caves used as dens and was unrelated to forest structure. At the den scale, pacaranas used deep caves (>4 m) in sloping rocky outcrops with >40% exposed rock (in 100 m2 patches). Pacarana groups (4 to 5 individuals) had a mean home range of 2.45 ha around caves. We estimated a population density of 9.9 and 5.5 groups km−2 based on sign clusters (footprints, latrines, and foraging areas) and dens, respectively. Pacaranas fed on a variety of plant families found in primary and secondary forest and disturbed areas near streams. Our results indicate that pacaranas can survive in forest fragments, and the main factor limiting their distribution and abundance is the availability of adequate dens. Conservation of pacarana populations in rural landscapes may be helped by protecting a network of forest patches connected by riparian vegetation, but these populations would be vulnerable to illegal hunting.