Selección de hábitat en Akodon azarae y Calomys laucha en semicautiverio. I- Efectos de la densidad de Calomys laucha sobre Akodon azarae

DE VILLAFAÑE, GLORIA; QUINTANA, RUBEN DARIO; MERLER, JORGE ALBERTO; BONAVENTURA, STELLA

MASTOZOOLOGíA NEOTROPICAL

UNIDAD DE ZOOLOGÍA Y ECOLOGÍA ANIMAL, INSTITUTO ARGENTINO DE INVESTIGACIÓN DE LAS ZONAS ARIDAS, CRICYT, CONICET

Lugar: Mendoza; Año: 1994 vol. 1 p. 123 - 133

0327-9383

Habitat selection in Akodon azarae and Calomys laucha in semicaptivity. 1 Density effect of Calomys laucha on Akodon azarae. Three experiments about habitat selection of Akodon azarae and Calomys laucha were conducted in semicaptivity. In each of three enclosures different habitat were created: 1) cultivated field edges, 2) soya and 3) corn stubble. One week alter the rodents were released, 35 Sherman traps were set for three days, and observed twice a day. The spacial distribution was studied in experiment I for C. laucha and in experiments II for A. azarae. Males and females were released in equal amounts and their densities were 4 individuals in enclosure 1, 6 in enclosure 2 and 12 in enclosure 3 respectively. In experiment III, the effect of several densities of C. laucha (4, 6 and 10 rodents/ enclosure) on the spacial distribution of A. azarae at a fixed density (6 rodents/enclosure), was studied. The results of experiment I show that the distribution of C. laucha was significantly related to the type of habitat. Soya was the most frequently used, and the densities did not show significant differences. In experiment II, it was observed that the spacial distribution of A. azarae was significantly affected by the type of habitat. This species principally used the microhabitat of soya and edge, and avoid the use of stubble. In experiment III, A. azarae, like in experiment II, preferd the microhabitat of soya and edge, avoiding the stubble. On the other hand, C. laucha used al1 three habitats.