In the northern part of its range, D. virginiana accumulates fat in the fall and may become inactive during severe winter weather, remaining in its nest for several days, but it does not hibernate. Females have a greater tendency toward winter inactivity and also are more sedentary in their movements at other times. Opossums have an extremely varied diet that includes small vertebrates, carrion, invertebrates, and many kinds of vegetable matter. Male home ranges overlapped one another extensively, and each overlapped the ranges of several females. The latter occupied exclusive home ranges for at least part of the year.
Opossums are basically solitary and antisocial, either avoiding one another or acting aggressively.
There almost always is extreme agonistic behavior when two males meet, but of opposite sexes meet during the breeding season, initial aggressive displays turn to courtship, and the two animals may spend several days together. If a male is placed with a female that is not in estrus, she becomes aggressive, but the male does not return her attacks. In this state the opossum becomes immobile, lies with the body and tail curled ventrally, usually opens the mouth, and apparently becomes largely insensitive to tactile stimuli. Death feigning may cause a pursuing predator to lose the visual cue of motion or to become less cautious in its approach, thereby giving the opossum a better chance of escape. He also suggested that catatonia may have evolved primarily as a means of reducing intraspecific aggression.