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bioRxiv · 10.1101/613943

Response of Bat Activity to Land-Cover and Land-Use Change in Savannas is Scale-, Season-, and Guild-Specific

Shapiro, J. T.·Monadjem, A.·Roder, T.·McCleery, R.
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Abstract

Tropical savannas are biomes of global importance that are under severe pressure from anthropogenic change, including land-cover and land-use change. Bats, the second-most diverse group of mammals, are critical to ecosystem functioning, but may be vulnerable to such anthropogenic stresses. However, there is little information on the response of savanna bats to land-cover and land-use change, especially in Africa. This limits our ability to develop conservation strategies for bats and maintain the ecosystem functions and services they provide in this biome. Using acoustic monitoring, we measured how guild-specific (aerial, edge, and clutter forager) bat activity responded to both fine-scale metrics of vegetation structure and landscape-scale metrics of land-cover composition and configuration across the wet and dry seasons in a savanna in southern Africa undergoing rapid land-cover and land-use change. We found that all three guilds responded more strongly to landscape metrics than fine-scale vegetation structure, although the specific metrics varied between guilds. Aerial and edge bats responded most strongly to the percent savanna cover and savanna fragmentation in both seasons while clutter bats responded to percent rural cover in the wet season and percent water cover in the dry. All three guilds responded more strongly to the landscape in the dry season than the wet season. Our results show it is possible to conserve bats, and the ecosystem services they can provide, in savannas undergoing anthropogenic land-use and land-cover change but strategies to do so must consider foraging guild, large spatial scales, and seasonal variation in bat activity.\n\nHighlightsO_LIBats in savannas respond to land-cover and land-use change on large spatial scales\nC_LIO_LILandscape had a greater influence on bat activity in the dry season than the wet\nC_LIO_LIAerial and edge forager activity responded to savanna cover and fragmentation\nC_LIO_LIClutter forager activity was best explained by rural and water cover\nC_LIO_LIMinimizing fragmentation and maintaining water promotes bat activity in modified savannas\nC_LI

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Shapiro, J. T., Monadjem, A., Roder, T., McCleery, R.. 2019-04-19. Response of Bat Activity to Land-Cover and Land-Use Change in Savannas is Scale-, Season-, and Guild-Specific. https://doi.org/10.1101/613943

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