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Measurement of bat guano deposition rate in caves can be an important research tool for estimation of colony size, for monitoring the record of long-term bat population trends, and for allied studies of guano invertebrate ecology, environmental contaminants, and paleoecology. However, previously published methodologies have lacked consistency. In the context of our recent studies of insectivorous bat guano deposition rates in Deer Cave, Sarawak, Borneo, we review some past studies and offer suggestions for best practises, along with proposed experimental design considerations for future studies (e.g., design of guano catchers, optimum deployment of catchers in relation to specific site characteristics, data reporting standards, and examples of mapping techniques). Consistent techniques will facilitate inter-site comparisons, and determination of intra-site changes over time. As a case study, and the first publication of detailed mapping of spatial variability in guano deposition rates, we present spatially explicit guano deposition rates for Deer Cave, ranging up to 88 g (dry weight)/m2/day in the main cave, and up to 540 g (dry weight)/m2/day in the northern extension. [ABSTRACT FROM AUTHOR]

This study examines the impact of habitat management on the seasonal and spatial activities of bat species in Mediterranean scrublands of southern France. Three study sites, presenting managed and unmanaged scrublands, were sampled by acoustic recording to assess their ecological potential for bat conservation. General linear mixed models (GLMMs) were used to identify the key factors driving variation in activity patterns of these areas. A total of 16 bat species were recorded, and no significant differences in taxonomic composition were found between managed and unmanaged areas. Bats have an opportunistic tendency to explore different habitats over long distances. In addition to the strong seasonal dynamics observed in most species, we found evidence of a shift in activity rhythms suggesting species adaptation to seasonal thermal variations and prey availability. In this study, the impact of managed areas on activity patterns depends on the functional traits of each species. Level of activity differed considerably from one species to another, suggesting that the 'management' effect is not the only ecological parameter involved in conditioning bats' preferred occupancy patterns. [ABSTRACT FROM AUTHOR]

We investigated the effect of anthropogenically-driven habitat modifications on insectivorous bat activity and diversity along a stretch of the Eerste River, Stellenbosch, South Africa, by determining insect abundance, water quality and vegetation and river characteristics at four sites of varying anthropogenic impact. Passive acoustic monitoring was used to determine species composition and activity of bats at each of the sites. A total of 14,457 bat passes was recorded, with the same six species being found at each of the sites: four clutter edge foragers (Myotis tricolor, Eptesicus hottentotus, Miniopterus natalensis and Laephotis capensis) and a single clutter forager (Rhinolophus clivosus) and open-air forager (Tadarida aegyptiaca). Bat activity was greater at the lower two most eutrophied sites, and greatest at the residential (urban) site. Laephotis capensis, an urban-adapted species, was by far the most active, probably on account of both insensitivity to light pollution, and roost-site availability. The highest and most pristine site (Eiland) and the lowest and most polluted site (Spier) displayed the greatest diversity, despite highly elevated levels of chloride and nitrate at the latter site. So anthropogenic effects on water quality appear not to have negatively affected bat diversity along this stretch of the Eerste River. As these effects are likely to increase, this study serves as a baseline for future monitoring of bats along its course. [ABSTRACT FROM AUTHOR]