PLASTICITY IN THE USE OF HABITAT BY MICROCAVIA AUSTRALIS IN THE MONTE DESERT (ARGENTINA)

ANDINO, NATALIA; CAMPOS VALERIA; CARTA SILVIA; BENINATO VERONICA; GIANNONI STELLA; BORGHI CARLOS

Mendoza

Congreso; IMC 10 International Mammalogical Congress; 2009

Microcavia is a rodent with wide distribution but restricted to arid and semiarid environments. The aim of this study is to describe the environment within the Monte where we located the species. This study was conduce in the Monte Desert of San Juan (Argentina) in four sites: -Matagusanos: mesquite woods (Prosopis flexuosa) and slimy clay soil;- El Leoncito: creosote bush scrub (Larrea nitida) and sandy silt soil; -La Cienaga: mesquite bush (P. alpataco) and clayey silt soil; -The Derivador: mesquite woods (P. flexuosa) and sandy silt soil. We quantified in active burrows (identified by fresh feces and footprints), the number of holes active and recorded: plant cover, stratum cover (tree, shrubs, herbs), percentage of bare soil and soil hardness. We used GLM in order to evaluate differences among sites and for to relate the microhabitat variables with holes active/burrow was used linear regression analyses. The plant cover was highest in Matagusanos (49.84±2.74) and was lowest in La Cienaga (21.22±4.76; F= 16.24; df= 3; p= 0.0001). The proportion of bare soil was highest in La Cienaga (63.50±4.91; F= 15.98; df= 3; p=0.0001) and the proportion of shrubs cover was highest in The Derivador (30±4.42; F=3.28; df=3; p=0.02). The holes active/burrow were positively related to soil hardness in El Leoncito (R2= 0.57; p= 0.02) and to bare soil in Matagusanos (R2= 0.40; p= 0.04). We found a negative relationship between cover plant and cave active/burrows in Matagusanos (R2= -0.63; p=0.03). In La Cienaga and The Derivador we not found relationship between cave active/burrows and microhabitat variables. This study shows that Microcavia is not strongly associated with any environmental variable selected in the four sites of the Monte desert . In consequence this plasticity in the use of habitats may to explain the presence of this species in arid environments with different features.