Bat species face multiple threats. One such threat, white-nose syndrome (WNS) has drastically reduced many bat populations. Also, habitat loss and fragmentation often forces bats to concentrate in remnant natural areas, or utilize habitats that are not as suitable. Both of these threats, while threaten bats in a general sense, also affect species differentially. The Oak Openings Region of Northwest Ohio is a biodiversity hotspot with a landscape composed of remnant natural areas within a matrix of agriculture and urban areas. This area, which provides crucial summer foraging habitat, has experienced declines in bat activity, shifts in bat assemblages, and some in diversity, in recent years, especially since WNS introduction. To study bats in this diverse landscape, we sampled bats acoustically from May – August 2016. We sampled mobile transects along roads along with stationary sites within the Oak Openings Preserve within the region. We identified calls to species and ran analyses investigating total bat activity, species-specific activity and presence, and bat diversity compared to. We compared bats to environmental, vegetation, road, and landcover parameters. Our results show that certain parameters influence bats as a whole, while others only affect one or a few species. We found that savanna stationary sites had more species-specific activity and bat diversity than forested sites (Rank Sums, p<0.05). Parameters that affected most bat species most prevalently were temperature and forest cover, both reflecting positive relationships with total bat activity and diversity (Chi-square; Rank Sums, p<0.05). When looking at species specific relationships, we focused on the least active species, as they may be more in need of management than more active species. Parameters that most influenced our least active species were humidity and open/savanna vs. forested sampling areas. Humidity had positive relationships with the likelihood of presence of our rarer species, while habitat type relationships depended on species specific life history traits (Chi-Square; Rank Sums, p<0.05). Our research suggests managing for forest cover across the landscape for all native bats; however, encourages managers to consider heterogeneity by maintaining both dense and open forest stands, along with open areas to benefit certain species.
Bat Diversity, Activity, and Habitat Use in a Mixed Disturbance Landscape
Title: Bat Diversity, Activity, and Habitat Use in a Mixed Disturbance Landscape
August 01, 2017
Thesis Type: Master's Thesis
Academic Department: Biological Sciences
Hollen, J. (2017). Bat Diversity, Activity, and Habitat Use in a Mixed Disturbance Landscape. Master's Thesis, Bowling Green State University.