The effect of a mega-fragmentation process on large mammal assemblages in the highly-threatened Pernambuco Endemism Centre, north-eastern Brazil

Abstract

We documented an example of the mass extinction in a medium-sized and large mammal assemblage in the Pernambuco Endemism Centre, one of the most important hotspots of the world. During 12 months we carried out diurnal and nocturnal surveys through the line transect method, in forest fragments measuring from 10 to 500 ha. About half of the species have gone locally extinct, including all large mammals. The largest number of species and sighting rates was recorded in the largest fragment. No fragment held the entire remaining mammal community and not all species sighted in the smaller fragments were present in the largest. Only two species were sighted in the very small fragment, the commonest fragment size in the entire Pernambuco Endemism Centre. The mammalian assemblage is highly simplified, and characterized by an unprecedented local extinction process. The abundance of the remaining population is far below the minimum viable population needed for long-term survival which needs to be taken into account by decision makers. The scenario here presented suggests that the 21st century fauna of this important hotspot will be dominated by small, generalist species, which can survive in close association with humans.