Most (uninformed) people will answer this question with the word "garbage" since that is what they seem to be eating fairly often. These birds get a really bad reputation since they are usually hovering around, beaches and parks waiting to be fed or for the chance to eat food that has been left behind. Garbage and left overs are not their first choice of food though. To easier answer the question, it is helpful to look at individual species of seagulls.
Black Legged Kittiwake
The hind toe located on this species gives this bird the nickname "three-toed" since they appear to have three toes instead of four toes. These seagulls eat plankton, marine invertebrates and fish. They feed while in flock formation and catch their prey at the surface of the water. They are unique since they are also capable of diving below the surface which make them rare. None of the other species of seagulls are capable of obtaining their prey under water.
Bonaparte's Gull
These seagulls are one of the few seagulls that nest during their mating season in trees instead of on the ground. These birds are found from Alaska to the Great Lakes and they feed primarily on insects, crustaceans, snails, fish and marine worms.
California Gull
These birds nest in a very shallow depression located in the ground that is lined with feathers and vegetation. They are found on the Pacific coastline and enjoy eating fish, insects and eggs. These are very famous birds that come to mind when the, "What do seagulls eat?" question is asked since they often scavenge docks and dumps. These seagulls are also often seen following a farmer as he plows his field and they eat any stirred up insect activity. They will also often find a swarm of flies on a beach, start at one end and literally run through the flies with its bill open and catch as many flies as it can.
These brazen birds will also "forage" your unattended goodies (they are not very picky!) right from your beach blanket, if you are not careful. They have been personally seen to take slow-sinking bait, becoming hooked on fishing line. They always seem to be quite surprised when this occurs.
The seagull eats a varied diet of fish and other ocean foods. The seagull will eat any fish that it is able to catch.
Big fish do not eat seagulls. Although, whales and porpoises do, in fact, eat seagulls from the ocean surface.
They eat sea fish and fish.
They eat sea fish and fish.
birds of prey,storks,seagulls,pelicans,puffins,penguins,loons,kingfishers,terns, albatross,boobies,ducks
Bear eat the fish known as trout.
seagulls and pelicans?
big fish and seagulls eat those big fish
The are seabirds that eat clam and fish.
Sometimes but they prefer fish.^_^
If it is dead yes - seagulls will eat just about anything including their own kind
seagulls eat fish, but hawks eat seagulls.
I have seen seagulls pluck small fish such as sculpin and blennies, as well crabs from kelp beds.