Brown bears are turning silver on remote islands

One of the brown bears pictured at the island of Kunashir. Picture: Kurilsky Nature Reserve

The picture shows a brown bear - but it looks distinctly white - on Kunashir island in the Kuril chain off Russia’s eastern coastline.

Snapped by Arctic expert Viktor Nikiforov, although a long way south of the Arctic, it shows an unusual occurrence with the coat appearing white or silver.

‘Brown bears have started to resemble polar bears in terms of colour because of inbreeding,’ he said. 'Kunashir is a relatively small island for brown bears, with no new individuals coming.'

This picture of a brown bear at the Kurilsky Nature Reserve was taken by Arctic expert Victor Nikiforov

There seems no clear idea of how the bears arrived.

One version is that they were introduced by the Japanese to the island.

Another is that they date from a time when the sea iced over or before the islands were detached from the mainland; they legged it, and possibly swam some of the way, from Kamchatka.

Professor emeritus Noriyuki Ohtaishi, of Hokkaido University, suggests the bears turned white - mainly on their upper body -  as a result of isolation and mutation.

Such bears have been spotted on Kunashir and Iturup on the two southernmost islands of the Kuril archipelago, and the two northernmost- Shumshu and Paramushir.

Professor emeritus Noriyuki Ohtaishi, of Hokkaido University, suggests the bears turned white as a result of isolation and mutation. Pictures: Kurilsky Nature Reserve

Some say brown bears were brought to the islands by the Japanese, which is more likely in the southernmost islands, where bears resemble those living in Japan.

In the northernmost islands, the bears resemble bears seem more closely related to their Kamchatka cousins.

Yet the bears are not only partly white.

Their colours range from almost black to silver, as if the species cannot decide what is right for them.

The colours were observed this year in a count of bears during the fishing season when the animals feast on salmon in island rivers.

Pictured below are one of Kurilsky Nature reserve brown bears, professor Ohtaishi, an automatic photo trap set at Kurilsky Nature Reserve to snap brown bears, and Island of Kunashir. Pictures: Kurilsky Nature Reserve, SKR, Albert Dyachenko