Thursday, January 31, 2013
Ring-billed gulls require about three years to achieve fully adult plumage, as in the birds in the previous two photos. This second cycle animal differs from an adult in its almost entirely black wingtips, and the prominent black terminal tail band.
This is a first cycle Glaucous Gull, with dingy white plumage throughout, no obvious gray mantle differentiation, and a dark eye. Glaucous are among the "white-winged gulls", which includes the Iceland Gull. These Arctic-breeding birds of the far north lack, or mostly lack, dark pigment in the wingtips as can be seen on this bird.