Florent Lefortier answered Seagulls have a really versatile diet – basically, they eat whatever they can get their little webbed feet on. They’re not exactly picky eaters!As seagulls usually live by the sea, they tend to eat a lot of fish. This is probably their main source of food.They’re also lucky in that they can drink both salt water and fresh water, whereas most birds and animals can only drink fresh water. What Else Do Seagulls Eat? Eggs from other birds (sometimes even taken from the nest)InsectsRodentsCarrionLizardsFruitSeedsClams (they smash the shells on rocks to open them and get to the meat)Mussels“Human” food like pizza, fries, chips, and hamburgers Seagulls have also been known to eat other birds – they’re great foragers, and will eat whatever they find, even if they didn’t kill it themselves.