Epaulets in Golden Eagle Plumages in Western Montana
An uncommon plumage characteristic of North American Golden Eagles (Aquila chrysaetos) is the epaulet, a white feather or feathers at the shoulder, often symmetrical on both sides in appearance. The size and shape of an epaulet varies by individual. This characteristic is mentioned within the literature, but is not noted how it is reflected within a population. We have observed epaulets in 17 out of 102 (16.6%) individual Golden Eagles with at least one epaulet in western Montana since 2012. Of these individuals, 13 (76.4%) were observed on the Rocky Mountain Front while on migration, and 4 (23.6%) were observed on wintering grounds in the Bitterroot Valley, Montana. Epaulets have been observed on both male and female individuals, and on both sub-adult and adult aged birds. This plumage characteristic should continue to be recorded in Golden Eagles for a better estimate of rate of occurrence within a population.