Master's Theses



Degree Name

Master of Science (MS)


We are currently in a sixth mass extinction event in which the extinction rate is higher than it has ever been. This mass extinction event is caused by human influence on the environment. Biodiversity is worth conserving because of its many uses to humans. Bats are a diverse group of mammals that humans rely on for pest control services. The gray bat, northern long-eared bat, and Indiana bat are on the Threatened and Endangered Species List and are in need of conservation. I built species distribution models using occurrence records, climate data, and Maximum entropy (MaxEnt) modeling technique. I predicted the historical range and projected the range into 2050 and 2070 in best- and worst-case future climate scenarios. The presence of each bat was most influenced by precipitation, which influences water availability, prey abundance, mortality, and natality. Future projected ranges became more fragmented, shifted north from the historical range, or both; and less of the historical range remained in the future. Fragmentation and shifting ranges due to changing climate could have a negative effect on each bat. I recommend conserving forested corridors especially around cave sites used by each bat species. Forested corridors will be important for dispersal when the range shifts or to connect fragmented areas. The models produced in this study provide a guide for conservation management efforts for each bat. Conservation efforts should strive to maintain or increase bat populations because of the economic and environmental benefits they provide.


Dr. Robert Channell

Date of Award

Spring 2017

Document Type



© 2017 Mitchell L. Meyer


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