About the Authors

L. David Mech

mechx002@umn.edu

Affiliation U. S. Geological Survey, Northern Prairie Wildlife Research Center, Jamestown, North Dakota, United States of America

Bruce W. Christensen

Affiliation Department of Population Health and Reproduction, School of Veterinary Medicine, University of California Davis, Davis, California, United States of America

Cheryl S. Asa

Affiliation Research Department, Saint Louis Zoo, St. Louis, Missouri, United States of America

Margaret Callahan

Affiliation Wildlife Science Center, Forest Lake, Minnesota, United States of America

Julie K. Young

Affiliation U. S. Department of Agriculture, Wildlife Services, National Wildlife Research Center, Department of Wildland Resources, Utah State University, Logan, Utah, United States of America

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Conceived and designed the experiments: LDM. Performed the experiments: BWC CSA MC JKY. Analyzed the data: LDM BWC CSA JKY. Contributed reagents/materials/analysis tools: BWC CSA MC JKY. Wrote the paper: LDM BWC CSA JKY.