The Inca tern (Larosterna inca) is a near-threatened species of tern in the subfamily Sterninae of the family Laridae (the gulls, terns, and skimmers). and has appeared as a vagrant in Central America and Hawaii.
Taxonomy and systematics
The Inca tern is the sole member of its monotypic genus Larosterna, and has no accepted subspecies.
Description
left|thumb|Two adults and a juvenile (left) in [[Lima, Perú]]
The Inca tern is roughly long and weighs between . Its plumage is uniquely colored among terns; adults have a mostly dark, slate-gray body, with paler underwing coverts, and a slightly paler throat. A white stripe extends back from the base of the bill and fans out like a Salvador Dalíesque mustache as long, satiny feathers along the side of the neck. The trailing edge of the wing (the tips of the secondaries and the three inner primaries) are white. The tail is black, and moderately forked. The iris is brown, with legs and feet that are dark red. The bill is bright to dark red, with bare yellow skin at the base. The chicks, on hatching, are purplish-brown, progressing through brownish-gray before developing mature plumage. The chicks' bills and legs are dark and horn-colored, and gradually attain the red that adults have.
Distribution and habitat
The Inca tern is an inhabitant of the Humboldt Current region. It breeds from Lobos de Tierra, in northern Perú, south to the Aconcagua River, near Valparaíso, Chile. Some disperse north into Ecuador after breeding, including a group of four together. It is a casual visitor to Panamá and Costa Rica, and has also been recorded as a vagrant in Guatemala and Hawaii. however, the species' popularity in captivity (see Captivity below) complicates assessment of extralimital records.
The Inca tern nests on sea cliffs and guano islands, as well as manmade structures (such as ledges under piers) and abandoned barges. It will gather with other sea and shorebirds on sandy beaches.