From The National Geographic:
To follow the movements of cougars in remote areas of western North America, a team of biologists has found a different kind of tracking device: a virus. Borrowing a method used to study human demographics, biologist Roman Biek and his colleagues took samples from 352 cougars in the Rocky Mountain region of the United States and Canada.
The researchers analyzed the samples for strains of feline immunodeficiency virus (FIV), which is common in big cats and does not appear to affect them. The analysis identified eight major FIV strains carried by cougars in Montana, Wyoming, British Columbia, and Alberta. These unique strains allowed the scientists to track where the cats had been and at approximately what time. One strain spread over a distance of 620 miles (1,000 kilometers), while others remained relatively isolated. Results of the team’s research appear in the current issue of the journal Science.
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