The White-tailed deer (Odocoileus virginianus) is a medium-sized deer found throughout most of the continental United States, southern Canada, Mexico, Central America and northern portions of South America as far south as Peru.
The species is most common east of the American cordillera, and is absent from much of the western United States, including Nevada, Utah, and California (though its close relatives, the mule deer and black-tailed deer, can be found there).
It does, however, survive in aspen parklands and deciduous river bottomlands within the Central and Northern Great Plains, and in mixed deciduous riparian corridors, river valley bottomlands, and lower foothills of the Northern Rocky Mountain Regions from Wyoming to Southeastern British Columbia. The conversion of land adjacent to the Northern Rocky Mountains into agriculture use and partial clear-cutting of coniferous trees (resulting in widespread deciduous vegetation) is in favor of white-tailed deer in this region.
The westernmost population, the Columbian white-tailed deer once was widespread in the mixed forests along the Willamette River (Willamette Valley Forests Ecoregion) and Cowlitz River Valleys of Western Oregon and Southwestern Washington (endangered).
There are also populations of Arizona (coues) and Carmen Mountains (carminis) white-tailed deer that inhabit the mountain mixed deciduous/pine forests of Arizona, New Mexico, and West Texas extending southwards into Mexico.
As a result of introductions, white-tailed deer are found also in localised areas of northern Europe such as Finland.
White-tailed deer are generalists and can adapt to a wide variety of habitats. Although most often thought of as forest animals depending on relatively small openings and edges, white-tailed deer can equally adapt themselves to life in more open savanna and even sage communities as in Texas and in the Venezuelan llanos region. These savanna adapted deer have relatively large antlers in proportion to their body size and large tails. Also, there is a noticeable difference in size between male and female deer of the savannas.
