The urgent, squeaky cries of a catbird in the willows off to my right could be one of two things, a dispute between two rival male catbirds or a nearby predator (more likely). Since there were a couple of cardinals and at least one towhee involved with the squawking and carrying on, it could only be one of those things, a predator was nearby. The intruder was either in the trees or just below the birds and the birds were mobbing the trespasser.
All of the birds were in a willow tree about fifteen feet or so out into the water, so it was probably a hawk in one of the trees or maybe even a snake. After a few minutes of searching I located the object of their raucous scolding, a Black Rat Snake.
Other birds came and went, but the catbird took the lead and persisted. The bird had a nest full of young in a nearby shrub and it was fighting for their lives. The other birds apparently didn’t have enough at stake to warrant a full on assault, their nests were perhaps farther from the snake and they were reacting more to instinct by joining in with the catbird. Many bird species will, stimulated by another bird’s urgent calls, come flying in to see what’s going on and may even help roust out an intruder, mobbing behavior.
And here is where the story seems to come to a mysterious conclusion. I turned and walked over to talk to some summer campers. When I came back with the campers to show them what I had seen, the snake was gone. Perhaps the snake dropped down into the water and swam off into the brush, but I can’t say for sure. It would seem though, that the snake posed no further threat to the catbird, all was now quiet and the catbird apparently had gone back to its normal routine.
Throughout the day I saw catbirds busily gathering food in the vicinity of the earlier assault. The birds would snatch up a blackberry or several insects in their bills and fly off to their unseen nest. This behavior suggests that the snake never found the nest, otherwise the birds wouldn’t be foraging with such earnest.
Considering the catbird’s behavior, it appears that there is a happy ending to this story, for the bird’s that is. But don’t feel bad for the snake, I’m sure it’ll find another nest full of tasty eggs or plump little nestlings a little further on up the road.
In the mean time, chalk one up for the birds!