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
Forster's tern nests are usually located deep within the marsh, either on tidal islands or evaporation pond islands, but also on manmade dikes. Nests are composed of adjacent marsh vegetation. Many nests are considered floating and are made of marsh grasses, then can be set on top of the vegetation or deposited on floating rafts of vegetation. In Manitoba, there is a strong association between Forster's tern nests and muskrat houses. They are, in fact, highly solicited nesting grounds. Also in Manitoba, Scirpus and often Typha are the main plants used for nest building. In the case of large colonies, nesting area