Wolves Help Restore Biodiversity in Yellowstone

Wolves have proven to be a big draw for tourists since they were reintroduced to Yellowstone National Park in 1995, but camera-toting vacationers aren’t the only species they’ve attracted. The park’s population of about 250 wolves seems to be spurring a general improvement in biodiversity, helping to bring Yellowstone’s ecosystems back into balance. Consider, for example, a cluster of willows growing along Black Tail Creek in the park. Before wolves returned to the area, the willows were routinely chomped by elk. Now that elk have to worry about being attacked by wolves, they avoid staying too long in open streambed areas, so the willows have been able to regenerate, attracting both birds and beavers, some biologists say. The beavers, in turn, appear to aid diversity themselves by building dams and creating pools of slow-moving water that attract otters, muskrats, moose, birds, and insects. “Wolves are to Yellowstone what water is to the Everglades,” said Doug Smith, head of the park’s wolf restoration program.