Mobbing among birds is very common

THE buzzard was having a bad day. It was trying to fly across the big field beside my house but it was being mobbed by 20 or 30 song birds of various species. The small birds were attacking it from above and behind, making loud alarm calls as they did so. As far as I could see all their dives were aborted at the last moment and no actual contact was made but it still must have been quite annoying for the buzzard.
Mobbing is an interesting piece of behaviour and it’s not confined to birds. As an example of convergent evolution it’s been observed among meerkats and sticklebacks, also California ground squirrels mob snakes and humpback whales mob killer whales. In fact Konrad Lorenz in his book On Aggression claimed that humans are subject to the same impulse to mob, although we are normally capable of bringing it under rational control.