Today, while birding with Caroline around the south end of Bond Lake, I heard a commotion above us that alerted me to the possibility that some birds had found an intruder, a predator worthy of their scolds. So we looked up and saw a snake, a Black Rat snake, I’m guessing.
I have read that an Acadian Flycatcher builds its nest just far out enough on a flimsy limb that a snake cannot eat its eggs or prey on its young, but not so far out on the limb that a wind could destroy its sloppy nest. I have found Acadian Flycatcher nests on a few occasions in the park, always in the American Hornbeams that line the paths. But I have never seen a snake up a tree until today. Because it is a real threat to all nesting birds, when one finds a snake, they call their neighbors and all gather to scold the scaly intruder and chase it off. Today, we caught these glimpses of their concern: