Yesterday, on 24 January 2016, Erika and I encountered a relatively pale Red-tailed Hawk. The raptor perched high in a tree between the Carleton College campus and the city of Northfield. Quickly three American Crows appeared and began harassing the hawk.
Why do passerines mob hawks? Two years ago, I blogged about Blue Jays mobbing a Red-shouldered Hawk. I wrote, “Several hypotheses exist for why small birds mob predators. Mobbing alerts nearby birds of the nearby predator. The hawk probably has trouble keying in on a single mobber, thus there may be safety in numbers. Mobbing may also drive a dangerous predator away.”