Do you wonder what all the raucus noise is about and why there are swarms of birds chasing a raptor? That action is called mobbing. It is often the best way a birder can locate a raptor. Mobbing is sometimes triggered by no more than the shape of a raptor rather than any immediate threat. A raptor may be set upon by a single bird or by a large mob. For example, in 2006 when the first eaglet fledged from its nest at Norfolk Botanical Garden several of us were there. What started as one crow chasing this fledgling on its first flight was soon nearly 100 crows that came from every direction. For that eagle, harassment by crows and other birds was now to be the way of life. They will sometimes sit and tolerate the frenzied attack for a time, but will soon fly away to escape the attack usually without any retalitation. Mobbing is not completely understood but the attacks and vigorous vocalization is believed to encourage the “enemy” to move on, and occurs most often during breeding season. Sometimes several species will combine their efforts to drive off an intruder into their territory. Mobbing occurs among many species of birds, not just raptors.
These photos were taken on the North Landing River near Honey Bee Golf Course in Virginia Beach over the past few weeks showing juvenile eagles being harassed by crows. The red-tailed hawk was being dive-bombed by a crow that was nearly the same size, and responded by screaming but also flew off to get away from the scolding crow. (Photos copyright by Reese F Lukei Jr)