Spectacled tern Spectacled tern The spectacled tern ("Onychoprion lunatus"), also known as the grey-backed tern, is a seabird in the family Laridae. A close relative of the bridled and sooty terns (with which it is sometimes confused), the spectacled tern is less common than the other members of its genus and it has been studied less. The three species, along with the Aleutian tern were recently split into a new genus "Onychoprion" from "Sterna" (Bridge "et al.", 2005). They resemble the sooty tern but with a grey back instead of a black one. Their breast and underparts are white, and they have
Royal tern the age of 4 years, after which they build their own nests and reproduce. Like all white terns, it is fiercely defensive of its nest and young. The royal tern and the Cayenne tern nest and breed together in Argentina and Brazil. The royal tern has few predators when it is mature, but before the chicks hatch or while they are chicks the tern is threatened by humans, other animals, and the tides. Humans threaten terns by fishing and by disrupting the tern nesting sites. Fishing nets can catch a tern while it is diving, making it unable to feed