Acadian? in Help Me Identify a North American Bird Posted May 23 3 hours ago, IKLland said: My votes for Traill’s. (Willow/Alder). Where exactly in Colorado? In the mountains near the Continental Divide. Traill's seems like the only other possibility, but bill is too long and thin for Alder (not to mention it would be exceptionally rare west of the divide), and the wings look much too long for Willow, and it seems to green.