Infodoc : Sciences, Techniques et Culture

While the effects of habitat loss are generally recognized as strong and negative, the effects of fragmentation are still very poorly understood as most studies did not control for total habitat amount. In addition, habitat loss is the primary source of fragmentation in natural settings, and consideration of these causal links is further necessary to understand there lative effects of these twin processes on biodiversity. Here, we assessed the direct effects of habitat loss and fragmentation on insectivorous bat sonotype richness, activity, and assemblage composition at both the assemblage and foraging guild level (forest, edge, or open space bats). Bats were surveyed using acoustic detectors across 28 landscapes of different habitat amounts (forest cover) and configurations (number o[...]

While the effects of habitat loss are generally recognized as strong and negative, the effects of fragmentation are still very poorly understood as most studies did not control for total habitat amount. In addition, habitat loss is the primary source of fragmentation in natural settings, and consideration of these causal links is further necessary to understand there lative effects of these twin processes on biodiversity. Here, we assessed the direct effects of habitat loss and fragmentation on insectivorous bat sonotype richness, activity, and assemblage composition at both the assemblage and foraging guild level (forest, edge, or open space bats). Bats were surveyed using acoustic detectors across 28 landscapes of different habitat amounts (forest cover) and configurations (number of patches and edge density) within the broad insular landscape of the Kenyir lake in peninsular Malaysia. We recorded 21,197 bat calls from which we identified 13 sonotypes, including 10 forest, 2 edgeand 3 open space. Overall, the indirect effects of forest cover mediated through edge density systematically out weighed their respective direct effects. The effects of forest cover were negative on richness and edge guild, but positive on forest and open space guilds. Fragmentation effects were mostly negative, yet strongly metric dependent. Our findings highlight that habitat loss and fragmentation cannot be managed independently: minimizing habitat loss is therefore essential to balance the negative effects of fragmentation on biodiversity.