All winter long, as the days fade quickly into night, hundreds to thousands of American Crows gather together to roost until morning. Steaming into the trees from all directions, the daily spectacle can be quite a sight. What are they up to and why do they do this? And when will it stop?
First, the good news, if your bedroom happens to be near one of these roosts and they are waking you up too early, it’s almost over. The Vermont Breeding Bird Atlas, a project of the Vermont Atlas of Life, found that American Crows begin building nests in late March, signaling the end to communal roosts as they spend more and more time on their individual breeding territories.
Why crows gather in such large roosts is still a matter of conjecture. One idea is that it is like a crowded hotel — simply a nice place to spend the night. And it might be safer to spend it with a bunch of others in case a Great Horned Owl, their worst enemy, comes for a midnight snack. Or it could be that crows gather information from others in the roost about food. A bird that didn’t find much one day, might be able to watch another that ate well to see where to go.