Feasibility of "Test-and-Cull" for Managing Chronic Wasting Disease in Urban Mule Deer

Strategies for managing chronic wasting disease (CWD) in urban mule deer (Odocoileus hemionus) populations are needed in Colorado. We captured, tonsil-biopsied, marked, and tested adult mule deer (n=181) to evaluate the feasibility of conducting an urban "test-and-cull" program in Estes Park, Colorado. During December 2002 and April-May 2003, we successfully tested 51 (57O/%) of the estimated 89 male and 130 (50%) of the estimated 261 female mule deer wintering in Estes Park for evidence of CWD. Nine (1 8%) males and 6 (5O/%) females tested positive for CWD infection via immunohistochemistry. All 15 test-positive deer were removed from the population; we culled 13 of these, and 2 died of other causes before being culled. We completed all sampling and inventory work in 34 field days and culled all test-positive deer in another 7 field days. Personnel time associated with sampling, culling, and inventory averaged 5.2 personhours/deer. Average drug costs varied by combination (tiletamine-zolazepam-xylazine: $22; thiafentanilxylazine: $66). Additional fixed costs averaged $21 5/deer for telemetry devices and $60/deer for vehicle and other testing-related expenses. Based on our initial assessment, sampling >50% of the mule deer in Estes Park annually is feasible.