Lesser Black-backed Gull

52-67 cm; span 1.35-1.55 m. Similar to Kelp Gull but longer winged; legs of adults always bright yellow; smaller, more rounded head; thinner bill without projecting hook at tip, vermillion patch on angle of lower mandible. Slaty-black upperwings and back but variable according to race and degree of feather wear - can develop brownish tone; white tips to flight feathers and white 'mirror' on outer primary are greatly reduced in worn plumage. Non-breeding birds may develop grey-buff streaks over face, crown and neck.