Five species of Gulls have been recorded in Galapagos, which include 2 residents, 2 migrants and 1 vagrant. Gulls are medium-sized to largish seabirds with long, pointed wings and longish, rather stout, hook-tipped bills, usually with a marked gonydeal angle. Their legs are longish and their feet webbed. The gulls recorded in Galápagos are predominantly grey and white in adult plumage, although the Lava Gull is wholly grey. The sexes are alike. Birds take a number of years to attain adult plumage and immature plumages are variable, often making identification difficult. Gulls feed by picking food from the surface of the water or by scavenging, often along the shoreline.