Bridled Tern

L: 37. W: 76.
Medium-sized slender tern; Sooty Tern being the confusion species. Dark ashy upperparts (but often appearing blackish), narrow white forehead-band extending behind eye as narrow supercilium, black cap contrasting with pale grey hindneck-collar and greyer mantle (often hard to see in flight); long outer feathers of deeply forked tail have white sides. Whitish underparts and underwing-coverts contrast with dark silver-grey central tail feathers and especially flight feathers. Underparts can appear grey. Juvenile lacks distinct supercilium, has pale grey-brown back and wing-coverts, edged buffish. Flight graceful with slimmer wings than Sooty Tern. Does not dive but takes food from surface of water. May settle on sea, with tail pointed upward at 45 degrees. Voice High-pitched kee-yharr, yelping wep-wep; also harsh grating karr; also a pleasing rolled purrurr or prerrr, day or night at sea or colony.