Cooperative Fish and Wildlife Research Units Program: Pennsylvania
Education, Research and Technical Assistance for Managing Our Natural Resources

Carrollo, E.M., H.E. Johnson, J.W. Fischer, M. Hammond, P.D. Dorsey, C.W. Anderson, K.C. VerCauteren, and W. David Walter. Influence of precipitation and crop germination on resource selection by mule deer (Odocoileus hemionus) in southwest Colorado. Scientific Reports


Mule deer (Odocoileus hemionus) populations in the western United States provide recreational, ecological and economic benefits to local economies; however, they can also cause considerable damage to agriculture. Damage to lucrative crops, particularly sunflower, can be common in agricultural areas of the western US. In some cases entire fields have been decimated by local mule deer populations resulting in a need for investigating resource selection and determining strategies for managing deer damage in these agricultural areas. Limited information exists on movements and resource selection of mule deer in agricultural areas, and no data exists to understand resource selection of mule deer in response to annual variation in crop rotation and climactic conditions. We used Global Positioning System (GPS) collars to monitor 14 mule deer and assess their movement patterns, home range and resource selection in southwestern Colorado, USA. We estimated home ranges for two winter seasons that ranged between 7.68 and 9.88 km2, and for two summer seasons that ranged between 5.51 and 6.24 km2. Mule deer were selecting for areas closer to forest and alfalfa for most periods during 2012, but selected for areas closer to sunflower in a majority of periods during 2013. Considerable annual variation in climate patterns and precipitation levels appeared to influence selection of mule deer due to changes in crop rotation and germination success of sunflower. Our results can assist managers in making informed decisions about crop damage prevention and practices by identifying areas and crops where mule deer damage is expected based on climate conditions and deer presence-absence.