Abstract
The species composition of samples of spiders and Auchenorrhyncha obtained using a Vortis™ and a modified garden leaf-blower/vacuum ‘G-vac’ was compared at three sites using standard sample areas and suction times. Both devices caught scarce ‘methodunique’ species not found by the other, but the G-vac caught more. The G-vac also caught a larger number of specimens in total. Rarefaction and extrapolation were therefore used to quantify three measures of species diversity (Hill numbers) with standardised sample size and sample coverage. Traditional rarefaction and extrapolation curves for the two devices, based on sample size, were not significantly different, however, estimates of species richness were higher for the G-vac than the Vortis at some levels of sample coverage implying a higher efficiency at discovering additional species using the G-vac. Some individual species were more abundant in the G-vac samples, but they were not associated with a specific microhabitat. There was, therefore, no evidence that the two devices were sampling different communities. The study reveals that Vortis and G-vac devices can provide consistent inventories of the more abundant species of spiders and Auchenorrhyncha, but that more scarce species are found with the G-vac, and fewer samples may be required with this device because of its tendency to capture more specimens per sample.