Pelicans use that big pouch like a fishing net. They scoop it through the water, catching a mouthful of fish and water at the same time, then they tilt their head, let the water drain out, and swallow the fish. The pouch can hold up to three times more than the bird's stomach.
Lake Kerkini, in the north of Greece, is one of the most important spots in Europe for Dalmatian pelicans. Hundreds of pairs nest there. The lake was made bigger by humans about 80 years ago, and the pelicans loved the change - more shallow water meant more fish.
Pelicans are surprisingly graceful in the air for such big birds. They glide on warm rising air called thermals, hardly flapping their wings at all, sometimes flying high enough to almost disappear. When they land on water, they put their feet out like skis and skim across the surface.
Volunteers in Greece have built special floating wooden platforms in the middle of Lake Kerkini to give the pelicans safe places to nest, away from foxes and other animals on the shore. Each platform fits several pairs of pelicans and their fluffy white chicks - the chicks look like tiny grumpy clouds with beaks.