Spring migrants are moving north. The first blackbirds have crossed the state line, and flocks of common grackles have appeared in the Bangor area. While we wait for the other migrants to arrive, we can amuse ourselves with the resident local birds that are gearing up for spring.
I refer to eagles, crows and ravens. Bald eagles nest early. Crows and ravens aren’t far behind.
They may not be on specific territories yet, but they’re thinking about it. Hence, they’re angry with each other. Crows and ravens are members of the corvid family.
They are clever and resourceful. They will raid the nests of other birds, including those of their fellow corvids, so they generally don’t trust each other. Eagles just take whatever they want, when they want it.
Naturally, crows and ravens don’t want them around as nesting season approaches. We’ve entered the season when ravens harass eagles, and crows harass both. It happens more than people realize, and it’s something to watch for.
The crows and ravens get aggressive when their nests contain eggs, and downright ferocious when the eggs have hatched. Nestlings are vulnerable to predation, and their parents won’t put up with much. There is a dam with a fish passage near my house, installed so that alewives could return to their historic spawning grounds.
It works. Alewives return each year by the millions. Three years ago, crows built a nest in my neighbor’s tree.
Eagles occupied their own nest a half mile away. The eagles vi.
