CONICET | Buscador de Institutos y Recursos Humanos

Vicuna, Vicugna vicugna, is one of the few large native herbivores of South American and it is considered a keystone resource for the Andean Region. We studied foraging ecology of free ranging vicunas at Laguna Blanca MAB-UNESCO Biosphere Reserve (Catamarca, Argentina), within dry Puna environment. Vicunas showed a stable diet throughout the year, with marked differences at spatial scale. Diet of vicunas included vegetation from all habitats, all vegetation strata and all functional groups of plants, suggesting that vicunas can use a large range of plant species that are distributed in almost all portions of their range (they used 39 of 75 available plant species), behaving as a generalist ungulate. Vicunas consumed large proportion of grasses (5972%) and shrubs represented 1619% of vicuna overall diet, reaching 45% at local sites, so we proposed that in this puna ecosystem vicunas do not behave as strict grazers. Although vicunas showed high diet plasticity, only two grasses, Panicum chloroleucum and Distichlis spp. represented nearly 50% of the diet. In relation to photosynthesis pathways of the plants, C4 grasses contributed higher to proportions in diet than C3 grasses. Vicunas showed a selectivity foraging behaviour by consuming swamp forages, low and medium vegetation strata, and a few plant species in more proportion to their availability. Vicunas did not eat plant species with more overall nutritional quality in higher proportion than species with less nutritional contents. However, the consumption of steppe grasses was in direct proportion to its crude protein content. This work brings a broad description of the foraging ecology of southern subspecies of vicuna, V. v. vicugna, by researching botanical composition and nutritional quality of the diet. These features of diet of vicunas can be considered as part of its wide range of feeding responses to live in the poor environment of altiplano.