The Black-legged Kittiwake is a sea bird that breeds on coasts around the North Pacific and North Atlantic oceans, but it is most commonly found in North America and Europe. They make large and very loud colonies when breeding, and are able to utilize the very sheerest of vertical cliffs.
There are two races of Black-legged Kittiwake: one in the North Atlantic ocean and the other in the North Pacific ocean. The first has a very small or even no hind toe, and thus in some European countries the bird is known as the 'three-toed' gull. The Pacific race does have a normally developed hind toe.