The home range of Ozotoceros bezoarticus is unknown, but this spcies is largely sedentary. No regular daily or seasonal movements are described. The pampas deer lives in small groups rarely exceeding 5 - 6 individuals. Most observations are of solitary animals. Groups are fluid in composition; the members, especially adult bucks, freely move from one group to another at any season. However, mother-young bonds appear strong with fawns staying with the maternal female all year. Males mix with females throughout the year. No evident habitat partitioning exists, either by sex or age. Sometimes, aggregations of up to 50 or more individuals form on common feeding grounds. When undisturbed during clement weather the pampas deer often lays on open feeding grounds to ruminate and rest. Reactions to disturbance include staring, peering, standing alert, footstamping and snorting, stilting, and tail raising. To avoid detection, the pampas deer also freezes if in cover, lies on ground, or crawls or slinks away. Agresive postures include glaring, a head-low threat and chase, striking with the forefoot, biting and antler-present threats; submisive acts include looking-away, exposing the neck, and commencing self-grooming.

During the mating season adult males compete with one another for the estrous females. They trash vegetation with their antlers and rub the scent glands on their heads and face on plants and other objects. Aggression is demonstrated by thrusting with the antlers or flailing with the forefeet. Flighting is frequent between males of equal size. There is no evidence of territoriality or of lasting pair or of harem formation. Several males may harry a receptive female simultaneously.

Pregnant females and those with neonates become secretive. Females physically defend their small young by foot stamping, snorting, feigning injury, and butting.

Jackson (1985, 1987), Jackson and Langguth (1987), Langguth and Jackson (1980).

Key Behaviors: motile; social