Bald Eagles in Cedar and Rush Valleys of western Utah were studied from 1975 to 1977. Arriving in mid-November, the eagles departed in mid-March. A statewide Bald Eagle census revealed 200 to 300 birds. Wintering eagle populations have remained stable for the past 10 years. Immatures comprised 35% of the population in 1975-76 and 33% in 1976-77. While Black-tailed jackrabbits are the primary food source of wintering eagles in western Utah, other mammalian carrion serve as supplementary food items. Eagles utilized 4 communal night roosts. Three day communal roosts were located on south facing slopes. The social existence of Bald Eagles on the wintering grounds may have survival value for immatures.
College and Department
Life Sciences; Plant and Wildlife Sciences
BYU ScholarsArchive Citation
Joseph, Ronald A., "Behavior and age class structure of wintering northern bald eagles (Haliaeetus leucocephalus alascanus) in western Utah" (1977). Theses and Dissertations. 7795.
Bald Eagle, Utah; Bald Eagle, Behavior