Defence against predators
Egg thief
As are many other animals, the black-headed gull is hunted by predators. Crows hunting for eggs and nestlings are the biggest threat.
Colony
Black-headed gulls nest in colonies which provide protection against predators. Several gulls together can more easily detect a predator and chase it away.
Mobbing
A crow that dares to come too close is thoroughly chastised. The gulls take flight and chase it away – screeching and diving at the intruder, attacking it with bills and feet, and bombing it with droppings. Sometimes the gulls take a special threat position in flight, with head and feet hanging, and wings lifted high and stiff.
