The more common and widespread species, Rissa tridactyla, is known in North America as Black-legged Kittiwake, but in Europe, where it is the only member of the genus, just as Kittiwake.
This bird is distinguished from other gulls by the absence of a hind toe. It has a grey back and is white below with black legs and a yellow bill.
Adults are roughly 40cm in length with a wing-span approaching 80cm. The name is derived from its call - 'kittee-wake kitte-wake'. It is a coastally breeding bird around the north Pacific and north Atlantic oceans, found most commonly in North America and Europe.
It breeds in large colonies on cliffs and the young are referred to as "tarrock" before they moult. Cliff nesting for gulls only occurs in the Rissa species. Kittiwake young are white, since they have no need of camouflage from predators, and do not wander from the nest like Larus gulls for obvious reasons.
They are fish feeders, and are more pelagic than Larus gulls outside the breeding season. They do not scavenge at tips like some other gull species.
The Red-legged Kittiwake, Rissa brevirostris, is a very localised Pacific species. Apart from the distinguishing feature implicit in its name, it is very similar to its better known relative.