Survival of Mule Deer in Northwest Colorado

Abstract

Survival of mule deer (Odocoileus hemionus) in Piceance Basin, Colorado, was measured with radio telemetry for 3 years on 1 study area and 4 years on another. Survival rates for deer >6 months old were estimated for yearly intervals beginning 1 December. Male and female fawns had similar (P = 0.254) survival, as did adult and yearling females (P = 0.567). There were significant differences (P 6 months old, yearling female, and adult female mule deer; (2) identify the timing and causes of mortality for ach age class; and (3) use a Cox model analysis to test for relationships between fawn size and overwinter survival. Financial support was provided by the U.S. Dep. Energy Contract W-7405-ENG-36 to Los Alamos Natl. Lab. and DE-FG02-85ER60297 to Colorado State Univ. Supplemental funding was provided by Colo. Fed. Aid Wildl. Restor. Proj. FW 26P and Cathedral Bluffs Shale Oil Co. We thank D. A. Garrott, M. A. Sovada, and D. L. Weybright for field assistance and the Bur. Land Manage. and local ranchers for their coop ration. B. L. Dupire, J. E. Morris and many other Colo. Div. Wildl. personnel aided in innumerable ways. Special thanks to T. E. Hakonson during the formulation of this study and K. V. Bostick for administration and logistic expertise. We appreciate the cooperation of T. H. Pysto of Cathedral Bluffs Shale Oil Co. in facilitating access to the shale oil lease tract and in helping trap deer. Numerous individuals participated in the annual trapping sessions. D. J. Freddy, T. M. Pojar, and W. D. Snyder reviewed the manuscript.