Guild structure, foraging space use, and distribution in a community of insectivorous bats in the Negev Desert

Abstract

Large-scale anthropogenic habitat degradation is taking place in the Negev Desert and such degradation is considered to be the primary cause of population decline in many bat species. A study of bat community structure in the central Negev Desert Highlands was undertaken to examine habitat associations, activity patterns and the distribution of bats in relation to landscape structure. During 1999 and 2000, mist-nets and bat detectors were used to capture bats and to monitor their presence in natural and artificial sites. In total, 12 species of insectivorous bats were found. Communities of insectivorous bats were divided into three guilds based on foraging space: open space foragers, background-cluttered space foragers, and highly cluttered space foragers. Bats of the background-cluttered space guild foraged over a variety of habitats while bats from the other guilds were more restricted with regard to their foraging spaces. In both years, season had a significant effect on bat activity. Despite there being significantly more bat activity in artificial sites than in natural sites, bat species richness was least in the artificial sites. For most species of desert-dwelling bats, areas that are typified by dense vegetation cover and have a perennial water source are of primary importance.