While you slept one night this week, more than 30 million migratory birds flew over Colorado, almost five times the number that were aloft the night before, at an average speed of 28 mph and an average altitude of 1,100 feet. And of those, more than half completely crossed the state en route to their winter habitat.
We know those things, and a whole lot more, because of a fascinating website operated by a consortium of ornithologists at Colorado State University, the Cornell Lab of Ornithology and the University of Massachusetts-Amherst.
It’s called BirdCast. It uses Doppler radar to detect birds in flight during migration seasons (fall and spring) the same way it tracks where it’s raining or snowing, except meteorologists filter out radar return from birds. Radar ornithologists filter out returns from weather.
