The Inca Tern, the genus Inca Terns of the subfamily Gullidae of the family Gullaceae. It is found along the Pacific coast from northern Peru to central Chile, inhabiting rocky shores or cliffs around sandy beaches. It often flies on the surface of the sea near the shore. Do not migrate, like to live in groups, often integrated in large groups. It makes all sorts of very loud cries, similar to "meow" or "cluck". It feeds mainly on small fish. Their foraging methods are by jumping into the water, diving to feed, and also floating on the surface of the water to catch fish. It generally breeds on nearshore islands and coastal cliffs.
Body length 39-42 cm, wingspan up to 80 cm, weight 180-210 g. Most of the body is dark grey and the tail is black. The posterior part of the wing has a distinctive white banded stripe that folds all the way to the tip of the black tail. The beak is bright red, larger and slightly curved. There was a small yellow feather under the eyes; at the corner of the mouth there were two long, curly bands of white feathers that extended from under the eyes to the neck, like two small mustaches. Their legs are shorter and dark red in color.
Tern, is a common name for most birds in the subfamily Tern of the gull family, and is named "tern" because of its similar tail shape to that of the domestic swallow. It is distributed all over the world, with the vast majority of it found in the tropics and subtropics. Its natural habitats are lakes , rivers , coasts , and swamps. The plumage is generally grey or white , and there are often black markings on the head. It is often active in small groups. It frequently flies over waters and swamps, flying briskly and agilely, with two wings flaring slowly and slightly. It mainly preys on fish, and in spring and autumn it loves locusts and grassland borers, and is a beneficial bird in grassland and agricultural areas.