Klute, David S., Loren W. Ayers, Michael T. Green, William H. Howe, Stephanie L. Janes, Jill A. Shaffer, Steven R. Sheffield, and Tara S. Zimmerman. 2003. Status Assessment and Conservation Plan for the Western Burrowing Owl in the United States. U.S. Fish and Wildlife Service Biological Technical Publication FWS/BTP-R6001-2003. Washington, DC: U.S. Department of Interior, Fish and Wildlife Service. https://www.fws.gov/mountain-prairie/species/birds/wbo/Western Burrowing Owlrev73003a.pdf