ANT COMPOSITION AND ACTIVITY IN NATURALLY-VEGETATED AND FARMLAND ENVIRONMENTS ON CONTRASTING SOILS AT KELLERBERRIN, WESTERN-AUSTRALIA

Two techniques, namely pitfall trapping and mapping of ant nests, were used in a study in Durokoppin reserve and surrounding farmland to determine the ant composition and activity in agricultural and naturally-vegetated land on two contrasting soils. The ant communities of various land use-soil type combinations are described as well as the seasonal fluctuations in ant foraging and nest-building activity. Ant fauna in the Kellerberrin area of Western Australia are highly diverse with 107 species recorded in the Durokoppin reserve and surrounding farmland. In wandoo (Eucalyptus capillosa) woodland on grey sandy loam soils there were 89 ant species and in mixed heath habitats on yellow sand soils there were 65 ant species. On equivalent soils in farmland, there were around 30 ant species. However, ant activity and next density were similar in native vegetation and in farmland when on the same soil type. For instance in the reserve and in the farmland on yellow sand nest density was 1.54 and 1.49 nests per m-2 respectively. Ant activity and species richness was lower in winter compared with spring and summer. The major functional groups in the farmland were opportunists and generalized myrmicine species, with Pheidole sp. DIO having greatest representation in terms of nest density and abundance. This particular species was only found occasionally in the reserve. Two species ubiquitous in the heath and woodland sites were Iridomyrmex (rufoniger gp.) sp. D13. and Monomorium sp. D8. The genera Camponotus spp, Melophorus spp and Iridomyrmex spp were well represented in naturally vegetated sites,