“The hopes and fears that we have on both sides of the debate – neither are realized. That doesn’t mean we shouldn’t allow the wolves, the mountain lions, to return to their traditional landscapes – they’re a part of it,” said conservation biologist Bernd Blossey, professor of natural resources and the environment at Cornell University. Blossey is lead author of “Myths, Wishful Thinking, and Accountability in Predator Conservation and Management in the United States,” published June 3 in Frontiers in Conservation Science. His co-author is Darragh Hare of Oxford University.
“Based on the currently available evidence (not just from the United States) large predators, despite their ability to kill ungulates and livestock, will not eliminate deer, threaten people or lead to intolerable losses of livestock – the myths,” the authors write. “On the other hand, large predators are unlikely to right all wrongs humans have inflicted on ecosystems – the wishful thinking.”
On the myths side, there is little evidence for claims that re-introducing large predators such as wolves, bears and mountain lions is a major threat to livestock and wild ungulates such as white-tailed deer, mule deer and elk.
When the U.S. federal government took the wolf off the endangered species list, hunters and livestock producers, and some state governments, called for action combatting what they saw as a need to safeguard the wildlife they wanted to hunt and the livestock that was their livelihood.
But it is nearly impossible to independently evaluate those claims, Blossey said. Other factors also kill livestock, from lightning strikes to hot or and cold weather, parasites, diseases, and poor husbandry and foraging conditions. And there’s much that livestock producers can do to protect their animals from predators, such as deploying more staff, guard dogs and fencing.
And hunters don’t need to worry about wolves competing for deer. The U.S. deer population is at an historic high, in part because humans have given them ideal living conditions and plenty of food. “What we do to landscapes, whether that’s forestry, agriculture or gardening, provide deer with a perfect landscape for them to live in,” Blossey said. “Hunters don’t remove enough deer, cars don’t remove enough. Their populations exploded, because the living conditions were just absolutely wonderful.”
And the wishful thinking – that wolves and other predators can control deer populations and restore degraded ecosystems – lacks evidence as well. When large predators are present in a landscape, deer and other herbivores simply graze when wolves are resting.
“Meaningfully reducing deer populations in Wisconsin alone would require tens of thousands of wolves, at least temporarily until deer populations decline – an ecologically and socially impossible scenario,” the authors write.
And wolves alone can’t undo the ecological damage humans have done, Blossey said. A popular video “How wolves change rivers,” which has been viewed more than 43 million times, suggests that the re-introduction of wolves in Yellowstone National Park triggered a cascade of effects that benefited the entire ecosystem.
“I was as fooled like everybody else by the lovely stories that came out of Yellowstone saying, you bring wolves back, and you restore the rivers, and everything’s hunky-dory,” Blossey said.
In fact, these claims may be based on the collection of selective evidence, other research has shown. “Once I started digging like an archaeologist into the literature, I found things that were not supportive of what I thought I knew,” Blossey said. Other factors, such as hunters, grizzly bears, mountain lions, bison, beaver, rainfall patterns, climate, and the quality and quantity of vegetation may have also played significant roles.
Rather than relying on myths and wishful thinking, we should see large predators like wolves as a valuable part ecological communities in their own right, Blossey said, and not just for their function.
“As long as people learn to live with and tolerate the new (old) neighbors,” the authors write, “a careful but not fully conflict-free existence appears possible.”
JOURNAL
Frontiers in Conservation Science
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