Dispersion and Habitat Use by Sympatric Columbian White-Tailed Deer and Columbian Black-Tailed Deer

Abstract

Sympatric Columbian white-tailed deer ( Odocoileus virginianus leucurus ) and Columbian black-tailed deer ( O. hemionus columbianus ) maintained a local geographic and habitat segregation within the interior valleys of the Umpqua River Basin, Oregon during May 1978–December 1980. O. v. leucurus occurred more often in portions of the study area within 1 km of the North Umpqua River than O. h. columbianus. Distributional patterns indicated that at least one species demonstrated interspecific avoidance. Densities of O. v. leucurus and O. h. columbianus were inversely correlated throughout their sympatric range. O. v. leucurus densities within the study area varied directly with percent woodland cover; the highest densities occurred in portions of the study area supporting ≥50% woodland cover. O. v. leucurus used lowland Quercus associations more often and lowland grassland and grass-shrub associations less often than O. h. columbianus. O. h. columbianus used lowland habitats more often in comparable environments supporting few or no O. v. leucurus. High densities of O. v. leucurus may preclude the use of corresponding habitats by O. h. columbianus .