The Inca tern, Larosterna inca, is a bird of striking appearance, cloaked in a dark slate gray plumage with a paler throat and underwing coverts. A distinctive white mustache-like stripe extends from the base of its bill, fanning out into elegant, satiny feathers along the neck. The trailing edge of their wings and the edges of the outer primaries are touched with white. Their tails are black and moderately forked, adding to their graceful silhouette. Adults boast a brown iris, dark red legs and feet, and a dark red bill with a patch of bare yellow skin at its base. Juveniles initially display a purplish brown hue, transitioning through brownish gray as they mature, with their bill and legs evolving from a dark horn color to the red of adulthood.
