Date of Award


Document Type


Degree Name

Master of Science (MS)



First Advisor

Dustin Ranglack

Committee Members

Glenn Plumb, Melissa Wuellner, Matthew Bice


Bison;Conservation;Green Status Assessment;IUCN;Management;Wild


The American bison (Bison bison subspp.), once on the verge of extinction, now number in the hundreds of thousands. Despite an understanding of their numerical recovery, a comprehensive survey of bison herds and how their management varies between sectors has never been completed, and neither has a critical evaluation of the level of ecological recovery of the species. I surveyed bison managers from all major sectors, collecting extensive information about each bison situation. I identified significant proportional differences between management sectors among my survey questions using Freeman-Halton-Fisher exact tests of independence. I visualized and grouped individual herds based on their adherence to the 2017 RLA criteria using a multiple correspondence analysis and hierarchical clustering analysis. I then used this information to conduct three nested iterations of the novel IUCN Green Status Assessment (GSA) with inclusion of herds in each iteration based on progressively relaxed definitions of “wild” from the most recent RLA criteria. In the end, I identified that inclusion of more bison herds in the assessment may increase GSA scores due to numerical recovery, but may lead to lower levels of perceived ecological recovery, posing important questions as we look into the future of bison conservation over the next 100 years.

Included in

Biology Commons



To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.