Red-legged kittiwake - The Red-legged Kittiwake is a very localised subarctic Pacific species. Apart from the distinguishing feature implicit in its name, it is very similar to its better known relative, the Black-legged Kittiwake; other differences include the shorter bill, larger eyes, a larger, rounder head and darker grey wings, and in the juveniles, which barely differ from the adults, lacking the black tail band and 'W' across the wings of juvenile Black-legged Kittiwakes. Juveniles take three years to reach maturity.
Black-legged kittiwake - This species was first described by Linnaeus in his Systema naturae in 1758 as Larus tridactylus.