The Southern Fulmar forms a superspecies with the Northern Fulmar (Fulmarus glacialis) of the North Atlantic and North Pacific oceans. Smaller-billed and more contrasting above than that species, the Southern is also restricted entirely to the Southern Ocean. It breeds in large colonies on cliffs and steep, rocky slopes on Antarctic coasts and subantarctic islands. Non-breeders, mostly young birds, wander north to the Humboldt Current off Peru and waters off southern Brazil. They often gather in flocks and regularly attend trawlers and other ships.