Procelsterna is a genus of birds in the tern family. It consists of two species, which are sometimes considered to be conspecific. Blue noddy, Procelsterna cerulea Grey noddy, Procelsterna albivittaThe 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.