Food remains at a Bald Eagle nest

TitleFood remains at a Bald Eagle nest
Publication TypeJournal Article
Year of Publication1965
AuthorsJr. JLTate, Postupalsky S
JournalJack Pine Warbler

On 14 July 1964 we visited the nest of a pair of Bald Eagles (Haliaeetus leucocephalus) on the Seney National Wildlife Refuge (Schoolcraft County) as part of the annual Michigan Bald Eagle Survey conducted by Postupalsky. The nest, located 45 feet high next to the trunk of an 80 foot red pine, contained one immature eagle near fledgling age and one eaglet which had died two to three weeks previously. After banding the one bird, we gathered the remains of the other and most of the identifiable food items about the nest and on the ground below. The sternum and pelvis of the dead nestling were chewed and broken, indicating it had been eaten, presumably by its nest mate. The cause of death could not be determined. Food items recovered included fish, mammals and birds. A total of 96 skeletal parts from prey were collected, representing 32 identifiable individuals. The presence of duck and goose remains is not surprising, for a large number of Canada Geese and several species of ducks are summer residents on the refuge. Whether the mammals and birds were healthy individuals at the time the eagles took them as prey could not be determined. Tate has observed Bald Eagles feeding on dead and wounded Canada Geese at Horseshore Lake Refuge in Illinois. Other animals, especially raccoon, coyote, and fox are known to prey on the geese at Seney and may have been responsible for some of the items found on the ground near the nest.