Species-specific low-temperature thresholds for winter active bats in North Carolina
- UNCG Author/Contributor (non-UNCG co-authors, if there are any, appear on document)
- Kevin A. Parker Jr. (Creator)
- Institution
- The University of North Carolina at Greensboro (UNCG )
- Web Site: http://library.uncg.edu/
- Advisor
- Matina Kalcounis-Rüppell
Abstract: Low winter-temperatures drive hibernation and migration in bats in temperate regions, which in turn can influence mortality via white-nose syndrome (WNS) and wind turbine interactions. However, the low-temperature during winter at which bats are able to be active remains unknown. I describe the species-specific winter low-temperature thresholds (TLT) for bat presence across the state of North Carolina (NC), USA. I defined the TLT as the sunset temperature (Ta) at which there was a certain probability of presence for that night and tested 10% (TLT 10) and 25% (TLT 25) levels. I studied two migratory species, Lasionycteris noctivagans and Lasiurus cinereus, and two cave hibernating species, Perimyotis subflavus and Eptesicus fuscus. I predicted that different species of bats would have different TLT , and that larger species would have lower TLT. I also predicted that migratory bats would have lower TLT than cave hibernating bats. I acoustically monitored bat activity from sunset to sunrise in the winter (December to February) of 2017 and 2018, across a large Ta gradient (mean winter temperatures -0.1°C to 11.6°C). I found all species to be present in the winter: L. noctivagans on 611 detector nights, E. fuscus on 242 detector nights, P. subflavus on 155 detector nights, and L. cinereus on 111 detector nights. In contrast to my prediction for migratory bats, the smaller bodied L. noctivagans had a lower TLT (TLT 10 1.01 °C Ta ,TLT 25 7.27°C Ta) than the larger bodied L. cinereus (TLT 10 13.76°C Ta ,TLT 25 18.79°C Ta). In support of my prediction I found that at low Ta, body mass is important in predicting probability of presence in cave hibernating species at TLT 10 (E. fuscus 9.65°C Ta, P. subflavus12.53 °C Ta), but as the Ta warms that effect weakens at TLT 25 (E. fuscus 16.92°C Ta, P. subflavus 17.76 °C Ta ). I found lower TLT 10 in species less affected by WNS, suggesting that behavioral adaptations to low winter Ta affect WNS susceptibility. My results can be used to model the progression of WNS in the southern USA, as well as improve our understanding of winter L. cinereus wind turbine collisions in NC. [This abstract has been edited to remove characters that will not display in this system. Please see the PDF for the full abstract.]
Species-specific low-temperature thresholds for winter active bats in North Carolina
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Created on 5/1/2019
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Additional Information
- Publication
- Thesis
- Language: English
- Date: 2019
- Keywords
- Acoustic monitoring, Climate change, Cold tolerance, Hibernation, Lasionycteris noctivagans, Winter activity
- Subjects
- Bats $z North Carolina
- Winter $z North Carolina
- Climatic changes
- Hoary bat $x Migration
- Silver-haired bat $x Migration
- Tri-colored bat $x Hibernation
- Big brown bat $x Hibernation