In adult males, levels of the hormone testosterone begin to rise. Snow usually melts and bears come out of their dens. Adult males are first to emerge from hibernation. Mothers with cubs come last. Food is very scarce.
Adult males begin to roam.
Most other bears remain lethargic and slow-moving, eating mainly aspen catkins and willow catkins. All but baby bears have been losing weight. The forest habitat begins to green up. Bears eat sprouting grass, emerging herbs and young tree leaves. Cubs taste what their mother eats, but swallow little except milk.