It helps expand populations and limits inbreeding. During summer, does and bucks are segregated, sedentary and spend most of their active time eating. Does and fawns travel and feed together throughout the summer. Does with fawns may spend 70 percent of their time eating to meet their high nutritional requirements. They often seek shrubby, thick cover because it offers better hiding and higher quality forage.
Bucks often congregate in bachelor groups composed of neighboring bucks.
Males typically use open habitats, such as mature hardwoods, fields and poorly stocked forests. Thus, they often are found in different habitats than family groups of does and fawns. Some deer researchers suggest males prefer open areas so that they can keep track of their position in the social hierarchy and to keep from damaging their antlers while feeding. Others theorize that the males' nutritional requirements are lower per pound of body weight or that their large rumens allow them to consume more food and gather sufficient nutrition from poorer ranges. Activity levels in deer are proportional to their nutritional needs.