Identification: Non-breeding adult has mostly white head with prominent dark ear spots, white nape and underparts, pale grey mantle, dark eyes, reddish bill with black tip and dark red legs/feet. Breeding adult has dark brown hood with broken white eyering and darker red bill. First winter bird resembles non-breeding adult but has duller bill and legs, buff-brown markings on upperwings and blackish subterminal tail-band.