Loss of forest cover impacts the distribution of the forest-dwelling tri-colored bat ( Perimyotis subflavus)

Abstract

Fragmentation of landscapes and the loss of species’ habitat by the expansion and intensification of human land use are major threats to global biological diversity, making it important to quantitatively characterize species’ distributions and resource requirements at multiple spatial scales. To examine the impact of landscape structure on the distribution of forest-dwelling bats, we examined the effects of these factors on the distribution and activity patterns of tri-colored bats ( Perimyotis subflavus) in Nova Scotia, Canada. In Nova Scotia maternity colonies of the tri-colored bat use clumps of Usnea spp. lichen for roosting, typically in mature spruce trees. In 2005 and 2006, we used Anabats to assess tri-colored bat activity at 90 river sites in southwest Nova Scotia. The results of echolocation monitoring indicate that the tri-colored bat occurs within a minimum area of 10,020 km 2. The best landscape predictor of the magnitude of tri-colored activity was non-forested land area within commuting distance of survey sites, suggesting that tri-colored bats were less active in landscapes where forests are cleared for agriculture, settlements and timber production. Therefore, this is an example of a forest-associated bat that seems to be negatively impacted by landscape practices that reduce the spatial extent of forests.