Eleven white-tailed (Odocoileus virginianus) does and their offspring (10 male and 6 female fawns) were radio-tracked for up to 56 months (2,725 total deer locations) in Minnesota's Superior National Forest from November 1974 through August 1983. All fawns wintered in yards with their does and migrated in spring to their does' summer ranges where they then separated from the does. By 17 months of age, seven males had established new summer ranges up to 9.6 km away, whereas the other three used the same summer ranges as their does, up to at least 29 months of age. One male established a new winter range, but six others continued to use the winter ranges of their does. The female fawns used the same summer range as their does, or areas immediately adjacent, and migrated to and from the same winter ranges, some with their does, for up to 3 years of age. The one female that we followed beyond this age migrated separately to and from the same winter yard during her fifth year. The data fit a hypothesis that non-incestuous inbreeding is common in vertebrates.