It turns out, not all hawks and other raptors (that is, sharp-beaked, sharp-taloned birds that hunt for animals) migrate to warmer climates. Older birds prefer to stay put in their established breeding territories, sticking out the cold weather. Maybe they don't want to have to reclaim their territories in the spring. Maybe they just plain don't want to bother migrating. Unlike songbirds and water birds, hawks don't flap their wings when they fly. Rather, they soar on updrafts they catch when they are airborne. They let themselves be carried by these as long and as far as they'll take them. For this reason, they tend to migrate less far than other birds. And they also don't migrate over big bodies of water, which don't provide updrafts. Migrating, it turns out, is a big hassle.
But what is there to eat if they stay behind? Other non-migrating birds, for starters. In New York City, where there are growing populations of Red Tails, that certainly means pigeons. But hawks also hunt for mice, rats, chipmunks, squirrels, rabbits. And, if necessary, they'll eat carrion—already-dead animals. The reason they perch in bare trees by the side of the road is that these give them a good view of the land: both of any little animals that might be scurrying out of their burrows, and also of any animals that might be lying in the road.
Have you seen any animals you weren't expecting to see this winter? Write in and let us know!