Use of space by the black-eared opossum Didelphis aurita in a rural area in southeastern Brazil

Abstract

Habitat fragmentation is a process that modifies the structure of an original community, favouring species that are matrixtolerant and harming species that are continuous habitatdependent (Laurance et al. 2002). The use of space by animals in fragmented environments can be affected by the arrangement of areas of suitable habitat and by the ability of the individuals to move through areas that are different from the original habitat (Gascon et al. 1999, Passamani and Ribeiro 2009). The movements of an animal in space are governed by the availability of resources in the environment and by interactions between individuals (Brown and Orians 1970). Home range is the term used to refer to the area used by an individual for its common activities (Burt 1943), and it plays a central role in studies of space use by mammals. The area used by an individual during its daily activities, or the daily home range, is a space use measurement often used in studies with neotropical small marsupials and rodents analysed with the spool-and-line technique (Delciellos et al. 2006, Almeida et al. 2008, Vieira and Cunha 2008). The black-eared opossum Didelphis aurita (Wied-Neuwied, 1826) is a generalist and opportunist marsupial that can become abundant in fragmented environments in the absence of natural predators (Fonseca and Robinson 1990). It is nocturnal, solitary and omnivorous, and plays an important role in pioneer plant seed dispersion (Caceres and Monteiro-Filho 2000). In the southern part of the state of Minas Gerais, Brazil, the development of agricultural practices and urban centres has modified the original landscape in such a way that native vegetation habitat is found in small and fragmented patches. Due to the generalist and opportunist characteristics of D. aurita, it has apparently become abundant in the remaining forest patches of the region (Silva and Pas-