Diet of the Mountain vizcacha (Lagidium viscacia Molina, 1782) and food availability in northern Patagonia, Argentina

PUIG, S.; FERNANDO VIDELA; MONICA CONA; MONGE S

ZEITSCHRIFT FUR SAUGETIERKUNDE-INTERNATIONAL JOURNAL OF MAMMALIAN BIOLOGY

Gustav Fischer, lena

Año: 1998

0044-3468

Diet of Lagidium viscacia and food availability were seasonally determined in La Payunia ProtectedArea through faecal analysis and point quadrat transects, respectively, in rocky elevations (shelter ofmountain vizcachas) and adjacent plains. There were several evidences of selective feeding behaviour,besides the little similarity between diet and availability. The diet included only 33% of the plant gen-era occurring in the environment, the main dietary elements being three grasses (Poa, Hordeum. andStipa) and one camephyte (Acantholippia). The proportion of grasses was significantly higher in thediet than in the environment, especially in the shrubby rocky elevations. The main food, Poa. wasscarce to absent in rocky elevations, where L. viscacia lives, representing evidence of L. viscacia's des-cending to plains for feeding. Similar behaviour was detected in L. peruanum and Procavia johnstoni,the rocky hyrax. The plains adjacent to rocky elevations in La Payunia were inhabited by the plains viz-cacha, Lagostomus maximus, a closely related species to L. viscacia. Considerable similarity betweenboth Chinchillidae diets suggests the possibility of competition, Poa being the key dietary element.Feeding behaviour of L. viscacia is focussed through the central place foraging theory, with rocky eleva-tions as shelter against aerial predators.