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SANTIAGO MARTIN
Department of Biological Sciences
Murray State University
Mentor: Terry
L. Derting
Title of Research: Changes in Bat Demographics and Capture Rates After the Detection of White-nose Syndrome in Kentucky
Presented at: Changes in Bat Demographics and Capture Rates After the Detection of White-nose Syndrome in Kentucky
ABSTRACT
In Kentucky, white-nose syndrome (WNS) was first observed in April 2011, but as of 2014 mortality at hibernacula has not reached the levels observed in the northeast U.S. My research questions were: 1) are summer bat capture rates of WNS-susceptible species lower post-WNS, 2) have bat demographics (i.e., proportion of sexes, proportion of ages, and proportion of pregnant females) of WNS-susceptible species changed since the detection of WNS in Kentucky, and 3) are changes in capture rate a product of proximity to hibernacula or environmental conditions at the net site (i.e., average nightly temperature, amount of forest, amount of water, and elevation). I assessed the significance of “year” in predicting capture rates of the four most commonly-captured species in Kentucky: the eastern red, big brown, northern long-eared, and the tri-colored bat. Mist-net site elevation, net distance to nearest cave, mean ambient temperature, total waterbody area, total stream length, and total forest area were used as covariates to take into account mist-net site characteristics that might influence the number and bat species captured. A trend of lower capture rates post-WNS was observed for the northern long-eared, tri-colored, and big brown bat, but only significantly so for the northern long-eared bat in 2014 compared to 2007. Differences in bat demographics post-WNS were not clear because similar demographic differences were observed for WNS-susceptible and non-susceptible species. My results indicated that WNS may be causing severe populations declines in the northern long-eared bat. Moreover, my results from mist net surveys indicated declines in big brown bat populations that were not detected by counts at hibernacula. Thus, information from summer mist-net surveys are an important tool to detect the effects of WNS on species difficult to count at hibernacula. |
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