The Gray Gull changes head color by season. In Chile it feeds along the coast and breeds inland in the Atacama Desert.
Its head is white in summer and pale brown in winter. The back and wings are gray-toned, the wings have dark areas and a white band, and the bill and legs are black.
In northern Chile it nests in colonies in the Atacama Desert, about 35–100 km inland. Birds fly to the coast to find food and may return in the evening to feed chicks.
An extinction-risk assessment has not been added yet.