Dispersal from the natal territory is usually male biased in Richardson's ground squirrels. Juvenile males typically disperse in June and July when they are 2-3 months old. Males that fail to disperse as juveniles are likely to do so as yearlings. Under conditions such as low population density and a small number of siblings, males may remain in the natal area, but they do not mate with close kin such as sisters or mother.
Juvenile female Richardson's ground squirrels tend to be sedentary, appropriating a section of their mother's home range for their own usage instead of dispersing to new territories. Because there are limits to the number of offspring that can share a mother's home range, in areas of high population density juvenile females will leave the natal area. (see Habitat and Range)
Sex-biased dispersal is not unique
to Richardson's ground squirrels, but occurs in a wide variety of species.
In mammals, males are generally the dispersing sex and females the sedentary
sex. Separation of the sexes reduces the likelihood of inbreeding.