Demographic parameters of Akodon montensis (Mammalia: Rodentia) in an Atlantic Forest remnant of Southeastern Brazil

Abstract

Abstract Small mammals seem to be affected by edge effects, hence understanding the local dynamics of these populations is important to assess the risks to which they are exposed. The objective of this study was to compare population size, sex ratio and home range size of the rodent Akodon montensis (Cricetidae) between the edge and interior of an Atlantic Forest fragment in the dry (June-August) and rainy (December-February) seasons. The population was sampled using capture-mark-recapture methods and a spool-and-line device was used to map the movements. The population size was significantly higher in the rainy season relative to the dry season, and this pattern can be related to the higher food availability in this period, as observed in other studies. However, there was no difference in the number of individuals captured in the edge and interior. The home range size showed no significant differences between edge and interior and between males and females, although, in a general way, the females showed a greater home range size related to the males. The absence of differences between edge and interior could result from the small size of the remnants and extrapolation of edge conditions to the interior.