EAGLE HABITS
Eagle use of the refuge during winter is dependent on the severity of the season. Open winters, where fish and other food resources are accessible results in fewer than 50 eagles. Hard winters where ice forms early and over a wide area could result in as many as 200 eagles on the refuge.
Small numbers of eagles begin to show-up on the refuge during late October. Immature plumaged birds outnumber the whiteheaded adults during October and November, but this ratio reverses later in the year. The winter population typically reaches its peak during the cold heart of winter in December and January.
During their winter stay, most eagles perch within 50 feet of the river-bank, preferring tall cottonwood trees in close proximity to their source of food. There appear to be five major communal roosts located within the Ft. Randall - Karl Mundt wintering area. Communal roosting promotes efficient exploitation of the food resources in the wintering area and allows a maximum number of eagles to roost at sites protected from the chilling winter winds.
The eagles feed mainly on fish in the Ft. Randall Dam tailwaters during the morning hours. Waterfowl, and carrion are eaten as opportunities provide. It is not unusual to see eagles cued up someplace near a large flock of waterfowl. Crippled birds are often identified and targeted by a low overhead flight that flushes the prey.
As February begins to wane much of the population leaves the area, following migrating waterfowl and dispersing to nest territories. By mid-March, bald eagles become uncommon on the refuge. The few that remain are usually incubating eggs by April 1.
EAGLE WATCHING
Eagles show some tolerance for human activity when they are feeding. When nesting, loafing or roosting however, they are very intolerant of human activity, and may abandon the area if disturbed too much. It is for this reason that the Karl Mundt National Wildlife Refuge is closed to public use. A kiosk with information on bald eagles and a mounted pair of binoculars is located on Corps of Engineers property directly below Ft. Randall Dam. From this observation point, visitors often get close-up views of eagles as they deftly pluck fish from the fast-flowing waters. Eagles loafing among the cottonwoods should be given wide berth by visitors.
EAGLES AND THE GOVERNMENT
The U.S. Fish and Wildlife Service has programs which address each of the major threats to eagles.
Habitat Destruction - The Service coordinates with other Federal agencies to prevent habitat losses caused by Federal development projects and by private developments which require Federal permits.
Pesticides - The U.S. Fish and Wildlife Service has conducted extensive research on the negative impacts that pesticides have on reproduction of several predatory birds. The Service monitors pesticide levels in the environment on a nationwide basis.
Electrocution - The Service cooperates with power companies to design power poles which will prevent electrocution of eagles.
EAGLES AND YOU
You can do a lot for eagles and other endangered wildlife by learning more about how they are protected. You can personally work to conserve endangered animals and plants by joining one of the many wildlife conservation organizations. You may also register your opinion when the Service makes proposals to add species to the endangered list and to designate critical habitat. You should report any violations of the laws protecting imperiled wildlife.
