The Wolf, Yellowstone National Park, Idaho, United States
Photograph by Stephen Wolfe
This is one of three wolves I followed until they decided to cross the road. The gray wolf is the largest member of its family, with males averaging 95–100 pounds, and females 80–85 pounds. In 1872, when Yellowstone National Park was created, populations of gray wolves were already in decline in Wyoming, Montana, and Idaho. By 1926, the last populations of wolves in Yellowstone were killed, although reliable sightings of the occasional wolf continued for decades – most likely single wolves or pairs passing through the area.
With the wolves gone, the effect on Yellowstone was immediately noticeable. The elk populations began to multiply, taking over the park without any natural predators to thin their herds. Overgrazing threatened several species of plants and trees and the threat of erosion and irreparable damage loomed large. The park began to trap and move the elk and eventually began to kill them to keep their numbers down, doing so for more than three decades. While this kept the land quality from worsening, it did little to improve the condition of the park.
It wouldn’t be until 1995 that the very first population of gray wolves was reintroduced into Yellowstone, beginning in the Lamar Valley. While the gray wolf was one of the first species listed as endangered under the Endangered Species Preservation Act of 1966, until the Endangered Species Act of 1973 there was no legal basis for re-introducing the gray wolf back into the borders of Yellowstone National Park.
In 1995 Canadian and US wildlife officials captured 14 wolves from packs east of Jasper National Park in Alberta, Canada. The wolves were initially released into three acclimation pens in the Lamar Valley in northeast Yellowstone, and at the end of March the pens were opened and the wolves were loose in the park. In April of 1996, seventeen additional wolves captured in Canada were released into the park. The current population hovers around 100 individuals, all descended from the original wolves released in 1995 and 1996.