By Alistair Doyle

OSLO (Reuters) - Polar bear DNA has been isolated for the first time from footprints left in the snow on an Arctic island, a breakthrough that could help scientists better protect rare and endangered wild animals, experts said on Tuesday.

Scientists often spend days tracking rare animals such as snow leopards or orangutans for samples of DNA, for instance from hair or faeces, to understand their movements, monitor their populations and propose ways to protect them.

Using "footprint DNA" from snow or mud could let them study animal numbers and movements more cheaply and without disturbing habitats. It could also free up cash for other measures, such as creating protected areas for vulnerable creatures.

"Animal tracks are what we find most often in the wild," said Arnaud Lyet of the WWF conservation group. Polar bears are a good species to study because DNA breaks down far more slowly in the cold than in the tropics.

Scientists collected snow around pawprints on the Norwegian archipelago of Svalbard, melted it and used filters to identify DNA genetic material from animal cells in the water, said Eva Bellemain, of French DNA specialist firm SPYGEN.

"This is the first time we have got polar bear DNA from a track sample in the snow," she told Reuters of the prints collected this year by an expedition by the Norwegian Polar Institute, WWF and Canon Inc.

Analysis of the samples turned up DNA genetic material of a polar bear, a seal it had killed and a seagull that had been seen nearby.

So far, the experts could only say that the DNA was from a polar bear. They were refining the technique as part of a next, vital step to be able to identify individual bears from the DNA left behind.

An international "Red List" of threatened species says that the polar bear is vulnerable to extinction because of a projected decline in its habitat linked to climate change that is melting sea ice in the Arctic.


(Reporting By Alister Doyle; Editing by Tom Heneghan)