The warm winter of 2005-6, with its late freeze and early breakup of lake ice, has given visitors to Frautschi Point a special treat. With the exception of about two weeks in January, there have been almost daily sightings of Bald Eagles (Haliaeetus leucocephalus) along the north edge of the Preserve, mostly at Frautschi Point but also near Biocore Prairie and in Eagle Heights Woods. Sometimes three eagles are in the area at the same time—two mature adults and one immature. They have regular perches high in shoreline trees, where they wait silently, sometimes for hours, until they see some kind of prey, generally fish. Then they glide down to open water, sometimes just a crack in the ice, grab the fish with their talons, and either eat it on the spot or carry it off to a tree perch.
Return from Near Oblivion
Bald Eagle populations declined drastically due to the heavy use of organochlorine pesticides in the 1950s. These pesticides were taken up by animals and accumulated in predators when they ate their prey. This resulted in thin-shelled eggs and poor breeding success of birds high in the food chain. By 1967, Bald Eagle numbers were so low that the species was declared "endangered" in the United States . Since the pesticide DDT was banned in 1972, the eagle population has steadily increased. During the past ten years, especially in mild winters, they have been abundant along the Mississippi and Wisconsin Rivers and relatively common inland, especially around rivers and lakes.
Adult Bald Eagle in Oak near Frautschi Point (G. Denniston)
Behavior of Local Wintering Eagles
Madison Bald Eagles are said to visit from their haunts along the Wisconsin River, flying here during
the day and returning to their river sites at night. In at least one instance, however, they were photographed at twilight in an oak on Frautschi Point. They are not normally nocturnal flyers. They are often seen very early in the morning, as well as late in the afternoon. Probably they sometimes sleep in the Preserve. Eagles are opportunists when it comes to eating. By preference they are fish-eaters, but they also kill rabbits, waterfowl and other birds and mammals. When the lake is frozen and food is scarce they resort to eating carrion, often in the form of roadkill. They are known for piracy, an especially important means of obtaining food for immature Bald Eagles (Fisher, D., "Piracy Behavior of Wintering Bald Eagles," The Condor, 1985) .
Wayne Hayes, a regular walker in the Preserve, recalls seeing eagles from his Eagle Heights apartment (number 610) during the five years he lived there as a graduate student (until 2002). He stated that they would sit quietly in one of the big maples outside his window and then swoop down to kill a rabbit on the lawn. They generally ate their prey on the spot. Usually they caught rabbits, though once one killed a young skunk.
 
Favorite Eagle Perch: Bur Oak Snag near Lake Mendota
Viewing Eagles at the Preserve
To observe eagles in the Preserve, move slowly and silently and do not look directly at them. Give them plenty of space – they are very wary of humans and have amazing vision. Please report sightings and behavioral observations on the Bird Sightings Board near the entrance to Picnic Point. For more information about the lives of Bald Eagles, see Paul A. Johnsgard's Hawks, Eagles & Falcons of North America.
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