Andean gull Chroicocephalus serranus

Handsome hooded gull of the Andes; also ranges to coastal areas in nonbreeding season. Found at lakes, wetlands, and bogs; ranging to plowed fields and farmland, and beaches and river mouths on the coast. Larger and stockier than other hooded gulls, with diagnostic wingtip pattern: broad white band in black wingtip; all ages have relatively small dark bill and dark legs. Breeding adult has blackish hood with white eyering. Immature and nonbreeding plumages have weak dark spot on cheeks.