Seagulls stomp their feet rapidly on the ground in a technique called "worm grunting" to find food. They stomp to cause vibrations that drive earthworms to the surface, where the seagulls can catch them. It is possible seagulls learned this from observing other birds, as crows are known to use tools. Once one seagull learns an effective foraging method, it spreads the knowledge to others through social learning, similar to how human children learn from watching others.