Game and cattle trampling, and impacts of human dwellings on arthropods at a game park boundary

Seven grassland sites were sampled at South Africa's Hluhluwe-Umfolozi Game Park boundary with the surrounding land, to assess changes in arthropod diversity in response to land use. Epigaeic arthropods were sampled using pitfall traps and a sweep net. In all, 262 morphospecies were collected, but this is an underestimate of total local species richness. Fifty percent of the species caught were single occurrences. The number of species, families and orders represented at each of the seven sites was not significantly different, but the number of individuals was significantly different. Between-site comparisons, using multivariate statistics, did not reveal any strong site groupings, with all sites being unique. The conclusion is that the reserve boundary does not significantly divide arthropod diversity on a simple inside-versus-outside basis. A major factor influencing the arthropod assemblages was intensity of land use. Indigenous game animals and domestic cattle had the same effect, and it was the intensity of trampling that was important rather than the type of trampling. Human settlements had a major impoverishing effect. The Coleoptera families, Cicindelidae, Staphylindae and Carabidae, were particularly sensitive indicator taxa of land use Scarabaeidae species were the only group that were severely affected by the fence boundary, simply because their food source, the faeces of large native mammals, was inside, leaving them without resources outside the reserve.