Invertebrate communities were monitored in a controlled sheep grazing experiment on ex-arable land on limestone and in nearby older calcicolous grasslands. Results for vacuum sampling of Heteroptera and herbivorous Coleoptera are presented and compared with the responses of spiders, leafhoppers and leaf-miners. Invertebrate groups differed in their responses to grazing and grassland age in terms of species diversity, abundance, variability over time and the development of a specific fauna on short turf. Leaf-miner assemblies were most strongly determined by the effects of grazing on plant species composition, while spiders' responses could largely be explained by the effects of grazing on plant architecture. Spider species simply accumulated over time, whilst leaf-miners were the most labile group. Spiders, leaf-miners and leafhoppers all contained some common species restricted to old grasslands, whilst herbivorous Coleoptera and Heteroptera did not. No single group demonstrated the full range of invertebrate responses. Spiders. leafhoppers and leaf-miners each showed useful features as "indicator groups", but more than one group should be chosen for study in the context of particular research projects.
