Original article on DiCaprio Foundation website.
By: Rebecca White
We are enduring the sixth mass extinction of life on our home planet. The Guardian UK recently reported on a studyshowing that 96% of all mammals remaining on earth are humans and livestock. Only 4% are wild mammals. Just since 1970, it is estimated we have killed off 60% of vertebrate wildlife. 40% of insect species face extinction. Scientists have stated that life will need 10 million years of evolution to recover from the onslaught of humanity on the wild world.
These numbers are horrifically difficult to read. On top of this, we are heating our atmosphere to the point at which large swathes of our home may become uninhabitable. And these twin crises – the biodiversity crisis and the climate crisis – are interlinked and self-perpetuating in ways we don’t fully understand.
But there is good news here, too: we are not alone in this battle. If we let it, the rest of life on earth will work with us to avert disaster.
Wolves as Partners in Fighting Climate Change and the Biodiversity Crisis
The gray wolf is a keystone species, without which its ecosystem “arch” falls in a jumble of nonfunctional rocks. It’s an apt analogy: the near-collapse of parts of Yellowstone National Park’s ecosystems after wolves were eradicated last century has become common knowledge.
A series of studies emerging from Yellowstone has explained how some of the park’s damaged ecosystems began to recover once their keystone was reintroduced. It’s a beautiful fact that indeed, ‘rewilding’ missing carnivores can restore ecosystems.
Wolves increase biodiversity. In Yellowstone, for example, the return of wolves led to changes in elk behavior that allowed streamside willows and aspen to regenerate. This in turn allowed for the return of songbirds, beavers, fish, and frogs. Wolves also feed their fellow species by leaving partially uneaten prey atop the winter snowpack, and thereby providing a feast for perhaps hundreds of other species from grizzlies to insects to fungi. Wolf-driven processes increase the complexity and health of their ecosystems.
Gray wolves can also contribute to climate stability. As a general proposition, functional ecosystems store more carbon. Beyond that, in some temperate forest ecosystems, the loss of wolves has meant the loss of new trees. Predator scientist Dr. Bill Ripple and others showed that when wolves were absent from Yellowstone, elk browsed all the young trees and shrubs from certain areas, leaving a 70-year gap in tree recruitment. His team found similar results in other North American parks where wolves had been absent for a time.
Photo showing missing age classes of trees in Canada’s Jasper National Park, where wolves were mostly absent for about 25 years. Image copyright and courtesy of: Bill Ripple
What’s more, wolves create conditions for beavers to thrive. Beavers alter the flow of water through an ecosystem, slowing its flow and providing rich habitat for a complex array of species. Too, beavers build wetlands and ponds, which can lock away a great deal of carbon.
We know that millions of wolves once roamed the North American continent. Now, only 5,000-6,000 grace the lower 48, where many hundreds of thousands once practiced their particular brand of ecosystem services. Many vibrant, carbon-sequestering ecosystems have been lost.
A map of historical gray wolf distribution (shaded gray area) versus current range (bright green) is stark. But dark green areas shows zones to which wolves might still return and thrive, and serve again as ecosystem engineers of the highest order.
Map courtesy of the Center for Biological Diversity
From Wolves to the “Warning to Humanity”
Emerging from a deep dive into climate and biodiversity data, Dr. Ripple penned the now-famous “World Scientists’ Warning to Humanity, A Second Notice.” It traces worsening trends in key metrics and calls on the world to decarbonize the economy immediately, to protect and restore natural systems, and to control human population growth.
Dr. Ripple sent the draft paper to 40 colleagues, hoping a few would sign on. By the time it was published, over 15,000 scientists from around the world had endorsed the warning, which went on to make international headlines and has become one of the most-cited papers ever published. It calls on leaders and citizens worldwide to make immediate and drastic changes in policy and behavior.
But at this critical juncture, when we are literally out of time and must try every potential method to stem ecological collapse, the Trump administration has proposed removing endangered species protections from gray wolves across the lower 48. Again, a mere 5,000-6,000 gray wolves remain here to do the work that hundreds of thousands once performed, and many, many habitats are still empty of wolves.
So much more than a wolf numbers game, this decision would turn wolf management over to state fish and game agencies. Although many states across the western U.S. have made headlines for their “green” governors and forward-thinking climate policies, most of our state fish and game departments remain mired in unenlightened, unscientific thinking about predator management. Rather than viewing keystone predators as partners in restoring healthy ecosystems for the benefit of all species, including humans, most “manage” wolves by killing them. In a time of urgent conservation crises, this is a terrible way to manage our precious and dwindling wildlife resources.
Americans are hurtling toward a decision that may make it impossible for our wolves to return home and partner with us in our efforts to stem climate change and biodiversity loss. We must not dismantle this crucial tool; the situation is indeed so dire that we must use all the options available to us. The Trump administration will likely soon finalize its proposal to remove federal protections from gray wolves across the lower 48. With enough voices speaking up to demand that we not only keep endangered species protections in place for our gray wolves, but that we actively work to help their populations recover in areas where they used to roam, we may yet correct that misguided course.