HABITAT CHARACTERIZATION OF Microcavia australis (Rodentia: Caviidae) IN A ROCKY MOUNTAIN IN LA LAJA.

LAHOZ VERÓNICA; ANDINO NATALIA; GIANNONI STELLA; BORGHI CARLOS

Conferencia; Segunda Reunión Conjunta de Sociedades de Biología de la República Argentina; 2011

The habitat used by M. australis (cuis chico) was characterized in a rocky place in the Mount desert of San Juan. We worked on five rocky places in La Laja, Albardon with individual`s presence and/or activity signs of M. australis. In each rocky place, we recorded its size, percentage of vegetation, rocks, mulch (litter) and bare soil cover. Also, we considered the dimensions of the entrances, overhangs and shelters in each burrow system, the orientation of each entrance and the soils hardness. In the study site, we found little vegetation cover (22.9%±2.39%) and high coverage of rocks (56.3%±3.56%). In the five rocky places we identified 52 principal burrow systems and 63 shelter burrow systems, both types of systems were differentiated by its depth. The entrances of the principal burrow systems were deeper than the shelters allowing individuals to find more stable microclimate in relation to depth. The shelter burrow systems had a greater number of entrances respect to principal burrow systems which would reduce the predation risk. The largest proportion of used entrances were orientated to the SW and S, which allows the entry of fresh winds in warm seasons to reduce the temperature within the burrow. In the study site, the vegetation cover would not be used as a shelter from predators, but that function would be carried by rocks, which also would function as a temperature shelter. In addition, the individuals of M. australis use the cracks and crevices of rocks because of the soil hardness. This work constitutes the first study of M. australis associated with rocks