FILE – In this April 6, 2016, file photo provided by the Yellowstone National Park Service, a white wolf walks in Yellowstone National Park, in Wyo. A wolf advocacy group has doubled the reward for information leading to whoever shot a similar rare white wolf found inside Yellowstone National Park. Yellowstone officials euthanized the severely injured wolf after hikers found the animal near Gardiner, Montana, on April 11, 2017. The park offered a $5,000 reward Thursday for information leading to a conviction after announcing a preliminary necropsy finding that the wolf had been shot. (Neal Herbert/Yellowstone National Park via AP)