The Black-backed Gull, also known as the Lesser Black-backed Gull, is a species of gull found in Europe and North America. Its scientific name is Larus fuscus and its three letter acronym is COB. This species of gull is characterized by its black back and wings, white head and underparts, and yellow bill and legs. It is a medium-sized gull, typically measuring between 45 and 55 cm in length. The Black-backed Gull is an omnivore, feeding on a variety of food sources including fish, insects, and carrion.