Bald eagles winter throughout most of the country, but they are most abundant in the West and Midwest. Bald eagles wintering in Nebraska are thought to originate primarily in the central provinces of Canada and the Great Lakes states. Migrant and wintering eagles begin arriving in Nebraska in early to mid October and leave the state for northern breeding areas by late March. Adult migrants tend to winter repeatedly in the same area, but remain mobile when seeking food during changing winter conditions. Winter night roosting occurs at sites where large numbers of eagles customarily congregate.
Eagles usually begin arriving at the communal roost within the last two hours of daylight.
They arrive as singles or as small disconnected groups sometimes travelling more than 10 miles from a feeding site. The first arrivals choose favorite trees and perches in the roost. Much vocalization occurs as new birds arrive and vie for favored perching positions. Before sunrise, eagles begin leaving the roost site for favorite feeding sites. Some communal roost sites in Nebraska are used by 100 to 200 bald eagles.