A giant bowhead whale caught off the coast of Alaska had a harpoon point embedded in its neck that showed it survived a similar hunt – more than a century ago.

Biologists claim the find helps prove the bowhead is the oldest living mammal on earth.

They say the 13-centimetre arrow-shaped fragment dates back to around 1880, meaning the 50-ton whale had been coasting around the freezing arctic waters since Victorian times.

Experts have pinned down the weapons manufacture to a New England factory in about 1880 and say it was rendered obsolete by a less bulky darting gun a few

 years later.

Fired from a heavy shoulder gun, the harpoon was attached to a small metal cylinder filled with explosives and fitted with a time fuse so it would explode seconds after it was shot into the whale.

Even though the device probably exploded, the bowhead was protected by a one foot thick layer of blubber and thick bones it uses to break through ice one foot thick to breathe at the surface.

Alaskan whalers found the harpoon fragment as they carved the 50-foot long whale up with a chainsaw after using a powerful 21st century gun to kill it.

While commercial whaling is now banned by international agreement, natives from Alaska, the Chukotka region of eastern Russia and Greenland are permitted to hunt a fixed number of whales for traditional, non-commercial consumption.