‘Landscape of Fear’: Reintroduction of Wolves Reshaped Yellowstone National Park’s Entire Ecosystem For Better, Even Changing Flow of Rivers

by Jon D. B.
Alpha female Gray Wolf (Canis lupus) Grey Wolf with subordinate males, Montana, USA. (Photo by: Dennis Fast / VWPics/Universal Images Group via Getty Images)

“This very small number of crucial predators,” or Yellowstone National Park‘s gray wolves, “altered the very nature of the land.”

Once abundant from Canada to Mexico, European settlers nearly wiped out North America’s iconic gray wolves completely by the 20th century. All native populations to Yellowstone were eradicated, leaving the national park without wolves for a century. And the land responded.

With the wolves gone, the entire Yellowstone ecosystem would transform in seemingly unbelievable ways – some of which scientists could never have known until these changes were reversed by the reintroduction of gray wolves.

“When wolves were reintroduced to Yellowstone National Park, in really quite small numbers, they quickly transformed much of the ecology. And even, to an extent, the physical geography of the park,” offers renowned environmental author and activist George Monbiot for the BBC this April.

‘The reason for this is what ecologists call the ‘Landscape of Fear’

“And the reason for this is what ecologists call the ‘Landscape of Fear,'” Monbiot pinpoints. “The deer they hunted began to vacate places where they could easily be caught… Like tight river valleys where they could be trapped. [They then] moved into other parts of the park where they could see the wolves coming more easily.”

Through fear of the predators, Yellowstone herbivores like deer, elk, and even bison left entire niche ecosystems. “The vegetation began to recover. The trees came back,” Monbiot cites. But this was only the beginning. The beginning of a deeply beneficial ‘Landscape of Fear.’

“When the trees came back, the songbirds came back. And the beavers came back because beavers eat trees. The beavers then transformed the rivers,” Mobiot smiles. “They created pools and riffle sections and a lot more habitats for wildlife than there were before – allowing ducks to come back. And otters, and fish, and newts and many other species.”

“The bears moved in to eat the berries growing on the young trees. The bald eagles came down to eat the carrion that the wolves had left behind.”

And because the wolves also killed foxes and coyotes, “Smaller predators like stoats and weasels, their numbers bounced back.”

‘Gradually, the whole ecosystem was transformed just by this small number of wolves’

The reintroduction of wolves to Yellowstone National Park would show how truly thin the distinction between the land – and the creatures that live upon it – truly is. If there even is a line at all.

“Gradually, the whole ecosystem was transformed just by this small number of wolves. And remarkably, in some places, because the trees returned to the riverbanks, the wolves actually appear to have changed the rivers!” Mobiot continues with a smirk of near-disbelief.

“The trees stabilized the banks and stopped so much erosion happening. Which then changed the shape and the flow of these rivers. So this very small number of crucial predators altered the very nature of the land.”

How Yellowstone National Park Reintroduced Wolves

Yet this reintroduction would never have happened without the U.S. Fish and Wildlife Service (USFWS) listing the northern Rocky Mountain wolf (Canis lupus) as an endangered species and designated Greater Yellowstone Ecosystem (GYE) as one of three recovery areas. They did so in 1973, but it would take another two decades for action to follow.

US Fish and Wildlife Service Director Mollie Beattie (L), US Secretary of the Interior Bruce Babbitt (C), and Yellowstone Park Superintendent Mike Finley (3rd L) carry the first grey wolf due for release into Yellowstone National Park in Wyoming to a holding pen in the park 12 January. The wolves will stay in their cages until the courts make a decision whether to set them free or not. (Photo credit should read POOL/AFP via Getty Images)

Throughout 1995, 1996, and 1997, 41 wild wolves from Canada and northwest Montana would see release in Yellowstone National Park. In the time since, YELL has ensured the species’ “long-term viability in GYE and has provided a place for research on how wolves may affect many aspects of the ecosystem,” the park cites. And January 12, 2020, marked a successful 25th anniversary of wolves returning to Yellowstone as a result.

As of December 2021, YELL knows of at least 95 wolves in the park, with 8 individual packs noted. Today, the Greater Yellowstone Ecosystem – slowly restoring to her natural, wolf-laden self – is home to over 500 wolves.