Wow! Record numbers (2,630) of migrating golden eagles were counted in the first season-long documentation of their numbers in a recently discovered flyway in the Big Belt Mountains of Montana.
http://www.greatfallstribune.com/story/news/local/2015/11/06/golden-eagles-counted-big-belts/75332630/
Thanks for that link,
T40. The article noted that:
"The Big Belts flyway was discovered by Rob Domenech, executive director of the Raptor View Research Institute in Missoula, Hoffman said. The institute tracks golden eagles with
satellite radio transmitters, Hoffman said."