Determinants of differential extinction vulnerabilities of small mammals in Atlantic forest fragments in Brazil

Abstract

From the nested structure often found in biological communities, it could be expected that the order of species loss after forest fragmentation would be predictable to some extent. This could expose the factors that would cause differential vulnerability of species to local extinctions in forest fragments. In this study, small mammals were sampled in eight small forest fragments and a larger area of Atlantic forest in Brazil for seven years. Multiple regression showed that tolerance to the matrix of grassy vegetation which separated the fragments was the main determinant of the vulnerability to local extinction, whereas other attributes of the species – fecundity, body weight, longevity, population density prior to the fragmentation, and degree of arboreality – were not good predictors of extinction vulnerability. Therefore, the connectivity of forest fragments is of paramount importance for the conservation of mammalian populations in Atlantic forest fragmented landscapes.