9/17/2014 4:52:45 PM
DNA in Polar Bear Paw Print Tells Tales
When a polar bear pads through the snow it has no idea that it's leaving a piece of itself behind. A very small piece.
Recently, scientists isolated DNA from polar bear paw prints left in the snow on the Arctic archipelago of Svalbard. Gathering DNA from the prints may allow scientists to obtain information about polar bears easily and without intruding on the bears.
After collecting snow from the paw print, the sample can be shipped to a laboratory for analysis.
Polar Bears International Senior Director of Conservation, Geoff York, said, "If this is successful, it could be another tool in the kit for studying polar bears in remote places like Russia and parts of Greenland. The beauty of this method is that you can collect samples on the ground and are only shipping water." York added, "It may also help refine methods for collecting genetic material from maternal dens in places where scientists rarely have access, but local people do, such as Wrangel Island and the Canadian High Arctic."
Scientists from the French DNA specialist firm SPYGEN, working in partnership with conservation organization WWF, were able to distinguish DNA genetic material of a polar bear, a seal it had killed, and a seagull seen nearby—all from the same sample of snow.
"The results are really exciting," Eva Bellemain, project leader for SPYGEN, told phys.org. "This is the first time we have been able to extract DNA from a track left by a polar bear - we found not only the bear's DNA, but also that of a seal and a seagull. We know from observations by the WWF team that the bear in question had just killed a seal, and that seagull had been seen at the kill site too, so this one footprint tells the whole story."
At this point, the researchers can detect the DNA of a polar bear, but cannot identify individual bears. The next step is to refine their technique to gather more data from samples.
York cautions that there are still plenty of caveats and the footprint DNA only contains basic information. But the new method may allow scientists to gain baseline information on remote populations with little to no impact on bears.
Polar bears are listed as threatened in the U.S. and as vulnerable to extinction on the international "Red List" of threatened species. They are losing the sea ice habitat they depend on for survival due to human-caused global warming.
Read more: Phys.org, Arctic expedition pioneers technique for polar bear research