Use of habitats by non-volant small mammals in Cerrado in Central Brazil.

Non-volant small mammals are organisms capable of yielding precise information on richness, abundance and species composition variations related to the use of habitats. The aim of this research was to compare these variations in Cerrado sensu stricto, Palm Forest, Gallery Forest and Rocky Field. From May 1999 to February 2000, we surveyed non-volant small mammals (hence small mammals) in Serra das Araras Ecological Station. We captured 218 individuals and recaptured 62 individuals, belonging to 21 taxa, 13 rodents and eight marsupials, in a total of 13200 trap-nights. Capture success was 1.7%. We observed higher richness of small mammals in forested areas (Gallery Forest and Palm Forest) than in open areas (Rocky Field and Cerrado sensu stricto). The Palm Forest had the highest richness of marsupials, possibly due to the quality of a specific niche. The Rocky Field had the smallest richness, but with very high abundance of few species, mainly Thrichomys pachyurus and Monodelphis domestica. Forest habitats had similar species composition. The open habitats, Cerrado sensu stricto and Rocky Field, had a distinct species composition between them, and also when compared to forested areas. Different species are exclusive or showed preference for specific habitats. The protection of horizontally heterogeneous biomes, such as Cerrado, has a fundamental importance to the maintenance of the regional diversity of the small mammal community of Central Brazil.