Fall Migration Field Trip Species List
Thursday, September 30, 2020 8:30 AM - 11 AM
Location: Jaffee Park and the Lower Gorge of the Roaring Fork
Fascinating behaviors and foraging techniques were the focus of today's outing. We started the morning with a dipper study when four of these highly adapted birds flew into the river in front of us. We watched as they fed in the fast-moving current and by reaching into the water from mid-stream rocks. Dippers also engaged in high-speed chases and low, direct flights up- and down-stream, and some flight calls and singing. At one point we were able to see seven individuals at one time. This is indicative of the high ecological health of this reach of the river, where aquatic insect life is abundant. We also studied yellow-rumped warblers as they used fly-catching techniques to forage on airborne insects in the airspace above the river. We practiced identifying them based on the unique black and white pattern in the tail that is visible when fanned out. Another highlight was a sharp-shinned hawk that flew in and perched in the low boughs of a spruce over the water. We learned from a comparison of Sharp-shinned field marks to those of a Cooper's hawk for practice with these nearly identical species. The rugged beauty of the gorge and the soothing sounds of rushing water were wonderful backdrops to the birds today. Join us next Tuesday at Hallam Lake!
~ Rebecca Weiss, ACES Bird Guide
Photo by Mark Fuller