Yellowstone Wolves Changed The Entire Ecosystem, Even The Geography — Here’s How

After about a 70-year absence, wolves were reintroduced to Yellowstone National Park when a nearly record-breaking number of public comments were reviewed in 1994. The Secretary of the Interior signed the okay for the reintroduction of gray wolves into Yellowstone only two decades ago, but there are currently between 400 and 450 wolves roaming Yellowstone.

Old Faithful and most of the world’s geysers are preserved at Yellowstone National Park, which was established in 1872 as the first national park in the United States. As tourists lined up to watch Old Faithful and enjoy the national treasure, wolves were rapidly killed off, because people feared the wolves. Government predator control programs helped eliminate the gray wolves from the national park, because as tourists came, there was nothing to stop them from killing the great predators.

The National Park Service reported that, in the late 80s, most scientists thought that if wolves were reintroduced into Yellowstone, they would not have much impact on the mule deer, bighorn sheep, bison or white-tailed deer population. In the beginning of the experimental reintroduction of wolves into Yellowstone, park staff created sites that were enclosed in nine-gauge chain-link fence. Plywood boxes were provided for shelter for the wolves. Eventually, wildlife biologists relocated wolves from Canada and released them into Yellowstone. The wolves were radio-collared. Now, only a small fraction of the Yellowstone wolves wear radio collars.

wolves Yellowstone Wolf Restoration Project.
"Wolves arrived in Yellowstone National Park via truck on January 12, 1995," according to the National Park Service.

Only a couple of decades following their reintroduction, the Yellowstone wolves have already accomplished remarkable feats, some claim. They reportedly rounded grazing herds back into their most natural territories, and in doing this, the native foliage returned, according to the remarkable video below.

Elk make up about 90 percent of the Yellowstone wolves’ diet in the winter months. In the video “How Wolves Change Rivers,” the narrator refers to elk as “deer,” but according to Sustainable Man that is simply a semantics issue.

“There are ‘elk’ pictured in this video when the narrator is referring to ‘deer.’ This is because the narrator is British and the British word for ‘elk’ is ‘red deer’ or ‘deer’ for short. The scientific report this is based on refers to elk so we wanted to be accurate with the truth of the story.”

After Yellowstone National Park reintroduced wolves into the wilderness, a trophic cascade occurred, according to the narrator of the film. Their return benefited everything from the bald eagle to the river’s flow. George Monbiot explains what a trophic cascade is, and how the Yellowstone wolves transformed the park’s ecosystem all the way down to its meandering riverbeds.

According to the National Parks Service, there is no way to know exactly how significantly the wolves’ return will impact or has impacted Yellowstone. Some scientists, like Arthur Middleton, who has in the past received funding for research from the Wyoming Animal Damage Management Board and the Wyoming Governor’s Big Game License Coalition, have opinions that oppose the idea that the wolves made such an impact. So far, according to the NPS, the impact that the wolves have made has been surprising in many ways.

“Preliminary data from studies indicate that wolf recovery will likely lead to greater biodiversity throughout the Greater Yellowstone Ecosystem. Wolves have preyed primarily on elk and these carcasses have provided food to a wide variety of other animals, especially scavenging species. They are increasingly preying on bison, especially in late winter. Grizzly bears have usurped wolf kills almost at will, contrary to predictions and observations from other areas where the two species occur. Wolf kills, then, provide an important resource for bears in low food years. Aggression toward coyotes initially decreased the number of coyotes inside wolf territories, which may have benefited other smaller predators, rodents, and birds of prey.”

According to Defenders of Wildlife, as the wolves return, the same old fears that led humans to nearly eradicate them are coming back too. Still, according to this same group, in areas outside of Yellowstone where the wolves are thriving in their comeback, less than one percent of livestock deaths have anything to due with wolves.

[Photos via the National Park Service]