Isle Royale National Park - The Slow Greening
By May Day, rose-tinged white hepaticas have begun to show on south slopes, and yellow clumps of marsh marigolds edge the brimming rivulets that stair-step down the drainageways. An advance guard of robins are sounding the first notes of the predawn chorus that will build up in weeks to come. Newly arrived song sparrows and white-throated sparrows announce that they are prospecting for territories in waterside brush. Somewhere among the aspens a mite of a bird, a ruby-crowned kinglet, bubbles forth a matchless melody.
Ice is gone from inland lakes, and it becomes evident that many winter residents and spring migrants have other plans for the coming summer. Mixed flocks of redpolls, siskins, and goldfinches are disappearing. Small wedges of whistling swans stop over to spend the night; in the morning, after clamorous calling and beating of wings, they arise, pink-tinted in the early sun, to be on their way to some Arctic breeding ground. Deepwater ducks are leaving too -- small flocks of scoters, goldeneyes, and oldsquaws that fished around shelf ice during the cold season. In the quiet of noonday, from a high shoulder of a ridge, comes a faint rasping cry: a wheeling bald eagle rides the thermals northward, a tiny fleck in the sky, white head and tail flashing momentarily against the blue.
About their 12th day of life, the wolf pups open their blue-gray eyes for the first time. In another week they will me moving about and venturing toward the sunlit world beyond the entrance of the den. Rearing the young is a communal affair with wolves, and in the early days of her parenthood the female is sustained by meat brought by other pack members, who carry it undigested in their stomachs. Sometimes the mother goes out to hunt with the pack, leaving another female in charge (baby-sitting comes naturally to any she-wolf, young or old). As the fuzzy, dark-furred pups develop, they make forays outside the den, romping, playing, exploring, already interacting as individuals.
In late May or early June a wise cow moose swims to an island in one of the inland lakes or makes her way to a heavy mat of sedge in a swampy area, where she gives birth to a spindly-legged youngster -- or rarely two -- weighing perhaps 25 pounds. The calf, covered with a woolly coat of brick-red hair, is able to stand almost immediately, but that is nearly the limit of its strength. After nudging her wobbly offspring to a sheltered place, the cow stands ferocious guard for three days or so, squatting or lying down from time to time so the calf is a month old and weighs about 80 pounds, it can follow its mother almost anywhere, including deep water.
Water is the semiaquatic moose's best defense; and so during the few months when lakes and swamplands are not frozen over, the wolf pack must supplement its usual diet with other prey. At this same time of year, beavers are vulnerable. When the spring litter is about to be born in a beaver lodge, the male and all the older offspring move out. Most of them establish temporary dens along the banks of the pond or of nearby streams; others pair off and seek new territory, where they begin to set up housekeeping by building new dams. Many members of both groups fall prey to wolves.