Small mammal diversity and density on the Bokkeveld escarpment, South Africa – implications for conservation and livestock predation

Abstract

A preliminary investigation of the diversity and density of small mammals in four structurally distinct habitat types in an actively-utilized farming landscape was carried out. We sought to understand how diversity and density are influenced by landscape structure, habitat structure and management decisions. Farmers in the area believe small mammals provide a service as an alternative food source, other than sheep, for predators. We assessed the validity of this reported ecosystem service. A total of 10 species and 219 individuals were recorded during this survey of 3600 trap-nights, with a total trap success rate of 6.1%. Significantly more individuals were caught during the winter than in summer. Vegetation transformation had a negative impact on small mammal diversity. Density, diversity and distribution were correlated with vegetation and landscape structural diversity. Management decisions that reduce vegetation structure and cover will have a negative impact on small mammal density and diversity. Ensuring the conservation of small mammals may have the benefit of providing an alternative food source to predators, a valuable ecosystem service to farmers.