At three weeks, the young are capable of crawling and by the fourth week, they can open their eyes. At five weeks, the young woodchucks are fully active. The female parent is reported to stand while she nurses her litter. She has four pairs of teats. Behavior Woodchucks are the most solitary marmots although several individuals may share a single den.
Woodchucks are usually highly agonistic.
Though observed mostly on the ground, woodchucks have been seen climbing trees to reach food and swimming with only their head and nose above water. Woodchucks are considered diurnal in their aboveground activities, although they have been observed feeding in dim light or even at night, especially when food is scarce. In the spring and autumn, activity peaks near midday and late in the day. In the summer, the animal appears more active in the morning and afternoon, preferring clear and sunny skies for maximum activity. When not feeding, woodchucks sun, scratch, and preen themselves outside their den while watching for potential enemies.