Microhabitat selection of five sigmodontine rodents in a forest-steppe transition zone in northwestern Patagonia

In a transition zone between Andean forests and Patagonian steppe, local po pulations of five sympatric species of sigmodontine rodents (Abrothrix long ipilis, A. xanthorhinus, Eligmodontia morgani, Oligoryzomys longicaudatus, Reithrodon auritus) were examined for their microhabitat use. The study are a represents a herbaceous steppe with sparse bushes. Over a four-year perio d, monthly samples were obtained by baited traps. The vegetation cover at e ach trapsite was monitored. The capture frequency in a particular microhabi tat turned out to be strongly correlated with the local vegetation cover. T his result is interpreted as a species-specific selection at a fine spatial scale of those microsites which resemble the characteristic environment in the area of main biogeographic occurrence of each of the rodents. The data on preferential microhabitat use might gather importance considering that two of these sigmodontine species are Hantavirus reservoirs.