Mobbing is a territorial behavior which can be observed in several common species, including especially the family Corvidae. During mobbing, a group of birds will make crazy twists and dives around an intruding animal which is threatening them, their nests, or their territory in general. The purpose is to scare the intruder, often a hawk or owl, away from the area to avoid avian casualties. Often several species will participate in one mobbing episode, ganging up together to chase off a single bird of prey.