Great Black-backed Gull Larus marinus

Great Black-backed Gull in flight
Great Black-backed Gull
Great Black-backed Gull
The Great Black-backed Gull, the worlds' largest gull, is larger and darker than the Lesser Black-backed, with pink-grey legs (instead of bright yellow). It is native to north Atlantic coasts of Europe (including the Baltic and Greenland) and America.
Great Black-backed Gull young Juvenile Great Black-backed
Great Black-backed Gulls Great Black-blacked size comparison with Lesser Black-backed
Toucan-billed Great Black-backed Gull
Toucan-billed gull

Kelp Gull/Southern Black-backed Gull

Larus dominicanus
Kelp Gull
Southern Black-backed Gull
Kelp Gull
The Kelp Gull, also called the Southern Black-backed Gull (New Zealand), is the Southern Hemisphere version of the northern Great and Lesser Black-backed. It's dark colour back looks like the Great Black-backed, but in size it is between the Great and the Lesser Black-backed. Its common appearance around the coast and its habits are more akin to the Lesser Black-backed Gulls.
Kelp Gull Southern Black-backed Gull with Blue Cod
Kelp Gull
Southern Black-backed Gull