Winter sets the stage for some of Minnesota's best bird-watching. As ice seals off lakes and streams in most of the state, the bald eagles that nested and fished near these bodies of water funnel southward along the Mississippi and congregate by the hundreds where currents or power plants keep the river ice-free.

One of the best places to watch these wintering eagles is the new National Eagle Center, perched along the river in downtown Wabasha. On a recent day, program director MaryBeth Garrigan dropped me an e-mail saying, "This morning out my office window, there are about 45 sitting on a point in trees and on the ice floes off the shore." On a recent weekend, spotters at the center counted nearly 100 eagles. One winter day, they counted nearly 700 in the 15 miles of river between Lake City and Wabasha.

The eagle center was the brainstorm of a band of citizens known as EagleWatch. For seven years, the group operated out of a downtown storefront. Last May the group opened its new facility, with a commanding view of the river at its doorstep.

Most winter days, visitors can watch feeding and resting eagles from either of two viewing decks, or the riverside trails, or even inside the center. "If you really don't like the cold weather," says Garrigan, "you can hang out in the atrium and watch the eagles." Indoors, the center has exhibits describing the eagle as a cultural icon of both Dakota Indians and modern Americans generally. Youngsters can use kid-proof binoculars.

And if by chance the wild eagles along the river are playing hide and seek, visitors can watch from just an arm's length away as the center's three captive birds -- Harriet, Angel and Columbia -- gobble their lunch. "Especially for children," says Garrigan, "seeing an eagle up close is a thrilling thing."

Eagle numbers soar

For casual bird-watchers, there's not a better bird to watch than the eagle. These aren't nondescript warblers, after all. They are familiar and huge. With a wingspan of about 7 feet, they are visible a half-mile way and are tough to mistake for anything else. When they perch at close range and tear into a large fish, you can hear bones crunch.

Not long ago, it was a rare thing to spot an eagle in Minnesota -- or anywhere else in the Midwest. During the 1960s, fewer than 500 nesting pairs survived in the lower 48 states. Nesting success of bald eagles and many other raptors and water birds had plummeted because absorption of DDT had caused their eggshells to thin and break.

Now, 35 years after the United States banned widespread use of the pesticide, bald eagles have returned in astounding numbers. Some 10,000 pairs breed in the lower 48 (with many more in Canada and Alaska). Minnesota alone has about 1,300 nesting pairs. The eagle's recovery has been so successful that last summer, the species flew off the federal endangered species list. Today, eagles live almost anywhere in the United States and Canada where lakes and streams provide an ample supply of their favorite food -- fish.

Birds congregate in winter

This abundance of eagles has made winter bird-watching all the more exciting. In late fall, eagles fly south to the nearest ice-free fishing hole they can find. For thousands of eagles in Ontario, Minnesota and Wisconsin, that generally means the Mississippi River.

One of the first reliably large ice-free zones they encounter is the confluence of the Mississippi and Chippewa rivers, where currents keep the main channel open from Reads Landing to Wabasha, no matter how cold it gets. There they roost in trees at night and patrol the open water during daylight in search of fish, primarily dead gizzard shad. (Bald eagles, being the adaptable birds they are, also scavenge road kill, scrounge for poultry-farm waste and hunt smaller critters such as waterfowl and rabbits.) In early winter, eagles share the open pools with ducks and swans that will then continue to move south.

The best eagle-watching around Wabasha usually happens in December, as eagles fly in from the north, and then again in early March as they congregate in anticipation of returning to their nesting sites. In the depth of winter, some birds, especially juveniles, will head south into Iowa. But even during extreme weather, some hardy adults remain in Minnesota all winter.

And not all of the hundreds of eagles that winter along the Mississippi return north in the spring. Some are year-around residents of the river. More than 160 will nest in the Upper Mississippi National Wildlife and Fish Refuge, from Wabasha downstream to central Iowa.

St. Paul travel writer Greg Breining is the author of "Return of the Eagle" and several other books of nonfiction.