Tree Swallows are gathering by the thousands on Plum Island as they prepare to migrate. We come across tall shrubbery that is sagging under the weight of the birds crowded onto them while roosting. Waves of Swallows will flow like a river over bodies of water as they dip down to catch drink in flight and fly just over and around us. These are a few photos from a cloud of birds that was swirling in the distance while I was photographing shorebirds. I could only capture a portion of flock with my long lens, even at the distance of almost a 1/4 mile (425 meters).
A Cooper’s Hawk flew among the swarm. It was quite distant but I didn’t notice it catching any of the birds while I was watching. The swirling motion of the flock, called murmuration when Starlings do it, distracts the hawk from easily selecting a target.
We will be watching this spectacular phenomenon for a few more weeks before the Swallows completely disappear until next summer.