Golden eagles (Aquila chrysaetos) are one of the largest aerial predators in the Crown of the Continent. Their main prey consists of small ground mammals like rabbits, marmots, and ground squirrels, although they will also hunt larger birds, mountain goat kids, and even domestic livestock if the opportunity arises. Golden eagles are partial migrants—some individuals may migrate as far as 3,000 miles, while others travel much shorter distances. In general, birds that summer in the far north are more likely to migrate farther. As many as 2,000 golden eagles have been counted migrating through Glacier National Park in the fall.
Research and MonitoringGolden eagles are listed as a species of concern in Montana, and data from areas surrounding Glacier indicate a recent decline in their numbers. Humans contribute to many golden eagle deaths each year, from wind turbines, vehicle collisions, poisoning from lead ammunition or pest traps, and other causes. Development is also encroaching on nesting and hunting grounds.
Current research on golden eagles in Glacier is aimed at obtaining accurate population counts to determine if their numbers are increasing, decreasing, or stable. Scientists conduct surveys in annual bird counts as well as by aerial surveys from aircraft. Recently, the park has enlisted the help of citizen scientists to participate in Glacier’s new Hawk Watch site. This site is one of many around the world where trained volunteers count migrating eagles and other raptors each fall.
Additional ResourcesA Survey of Golden Eagles in the Western U.S., Mid-winter 2017
Yates et al., 2001.The Influence of Weather on Golden Eagle Migration in Northwestern Montana
Last updated: January 30, 2019