Researchers recently discovered the importance of Montana’s Big Belt Mountains (near Bozeman) as a raptor migration flyway, and their first major monitoring effort for this flyway began in the fall of 2015, and was repeated in fall 2016. This route recorded the greatest number of migrating golden eagles of any site in North America, with 2,620 golden eagles recorded, with a peak of 24 goldens per hour!
The team also recorded another important behavior: Golden eagles continued to migrate at night under a full moon.
And if the golden eagle information wasn’t enough, the researchers also documented all 17 raptor species known to migrate through the region – all on one day!
The Big Belts are a 75-mile long mountain range in west-central Montana, just north of the Bridger Mountains, which are well-known for raptor migrations. The raptor migration counts were conducted by Ronan Dugan and Jeff Grayum of the Golden Eagle Migration Survey and the report on the Fall 2016 counts can be found here.