Rare fish turns up on wrong side of the world

The captain of a Danish fishing boat caught the surprise of his life when he netted a fish that usually lives on the other side of the world.

Olaf Solsker, the skipper of the Isak L, was searching for halibut off the coast of Greenland when his nets pulled up a Patagonian toothfish, which normally resides in Antarctic waters more than 6,200 miles away. Although Captain Solsker was not able to identify it he knew it was unusual enough to take to fish experts at the University of Copenhagen.

Peter Moller, Jorgen Nielsen and Inge Fossen, from the university's zoological museum, found that the creature was a male Patagonian toothfish, almost 6ft long and never before seen further north than the coast of Uruguay.

"This indicates large, cold-temperate fishes may occasionally migrate from sub-Antarctic to sub-Arctic waters by using deep, cold water," the researchers write in the journal Nature.

Captain Solsker's catch might begin to explain the riddle of how such fish can move from one pole to another without being killed by the warm water in between.