Following in polar bears' footprints: DNA from snow tracks could help monitor threatened animals

Polar bears are icons of the Arctic, elusive and vulnerable. Detailed monitoring of their populations is crucial for their conservation—but because polar bears are so difficult to find, we are missing critical data about population size and how well-connected those populations are. Scientists have now developed a new tool to help: DNA analysis using skin cells shed in the bears' footprints in the snow.