Procelsterna is a genus of birds in the tern family. It consists of two species, which are sometimes considered to be conspecific. \n* Blue noddy, Procelsterna cerulea \n* Grey noddy, Procelsterna albivitta The grey noddy is sometimes considered to be a morph of the blue noddy. These are grey-plumaged terns of tropical oceans, which nest colonially. They feed on small fish picked from the surface.