In this installment of the occasional series, we hear from Cristina Eisenberg, author of The Carnivore Way.
Q. What drew you to decide to study large carnivores?
A. n the mid-1990s, our family moved to a part of northwest Montana where there were more large carnivores (grizzly bears, black bears, and cougars) than there were people. By the late 1990s wolves had begun to naturally recolonize our land, dispersing south from Canada, driven by their instinct to leave home, find a mate, and claim new territory. One day my young daughters and I saw a pair of wolves hunting on our land. The following year we heard wolf pups howling—evidence that the wolves had formed a pack and produced pups. And within four years, things had changed noticeably on our land. The deer and elk had to be much more alert to avoid getting killed by wolves. This reduced these herbivores’ impacts on plants. Soon a meadow that had been heavily browsed by deer and elk became filled in with tall shrubs and trees. At the same time, bears and cougars continued to live on our land. These fascinating food web relationships inspired me to become an ecologist. I waited until my daughters grew up a bit then went to graduate school to learn more about how large carnivores help create healthier ecosystems—and how humans can live more peacefully with them.
Q. How would you characterize human-carnivore relationships throughout North America?
A. I characterize our human relationships with carnivores as being in flux. Initially, these relationships resembled a war. We killed as many carnivores as we could, because as we settled North America and ranching spread across the West in the 1800s and early 1900s, the prevailing wisdom was that the only good predator was a dead one. However by the 1930s and 1940s, conservation leaders such as Aldo Leopold and Adolph Murie were teaching us that carnivores are essential to the healthy functioning of ecosystems, as part of nature’s “checks and balances.” Inspired by these conservationists’ insights into how nature works, between 1970 and 2000 we created powerful environmental laws in the US, Canada, and Mexico. Since then we have been working hard in these nations to recover species such as wolves, grizzly bears, and jaguars. As endangered carnivores are reaching the recovery goals mandated by environmental laws, we have begun to remove protection from them. In the US, the federal government has given state governments responsibility for carnivore management. In the case of the wolf, states are proceeding to greatly reduce numbers of this species through hunting and control actions. Some experts believe that by managing wolves as intensively as we are today (i.e., reducing their numbers severely), we are taking a huge step backward and resuming the predator wars. In other places, such as Alaska and the Yukon, predators have never been protected. In these far northern lands, today we are debating adopting a more tolerant approach toward predators. All of this suggests that while we have come a very long way in carnivore conservation, we still have far to go in learning to coexist with recovered populations of these animals.
Q. In the book, you profile six species, each of which faces unique biological and ecological challenges: grizzly bear, wolf, wolverine, lynx, cougar, and jaguar. Which of these most surprised you as you researched the book and how?
A. Of all the species I profiled in The Carnivore Way, I was most surprised by the wolverine. Widely characterized as a fierce, tenacious carnivore, I was astonished to discover that even under the best conditions, members of this species often starve to death. When you add to that the profoundly negative impacts on the wolverine of climate change, fur trapping, and human development, you see that this species faces a most uncertain future. Today heroic measures are being considered to save this species from extinction in the 48 contiguous United States, such as a reintroduction in Colorado, which has more than twenty peaks above 14,000 feet in elevation. Yet, despite these measures and the wolverine’s formidable nature, it remains highly at risk.
Q. Why is habitat connectivity so important and what tactics can we use to increase it without impinging on human priorities?
A. To thrive, carnivores need connected habitat. Habitat connectivity is the ability of the landscape to allow animal movements and other ecological flows. The ability to move is the key to survival for large carnivores and many other species. Movement corridors function like lifelines, enabling animals to flow from one core area to another and to disperse from the place where they were born to a new home. Carnivores and other species use dispersal as a key survival mechanism to maintain genetic diversity. Species also use dispersal to adapt to climate change. Large carnivores have taught us that they need lots of space, and that national parks aren’t enough to meet their fundamental needs for food and a mate. For example, in the 1990s, during an eighteen-month period, Pluie, a young Canadian radio-collared wolf, traveled an area that encompassed more than 40,000 square miles, crossing more than 30 legal jurisdictions, including two Canadian provinces and several US states. She demonstrated that carnivores need connected landscapes that transcend political boundaries, and that thinking about conservation on a continental scale is essential in order for us to restore and recover carnivores. Pluie inspired conservationists and scientists to find continental-scale solutions, using the science of corridor ecology. These solutions include crossing structures, such as the Bow Valley wildlife crossings in Banff, which enable animals to find safe passage over the Trans-Canada Highway’s four lanes of heavy vehicle traffic.
Q. What are the strengths and weaknesses of wildlife management legislation in North America?
A. That we have any carnivores left at all today is due to the web of environmental laws that protect them. This imperfect web provides the framework for wildlife conservation across the three nations in the Carnivore Way: Canada, the United States, and Mexico. In Canada, the Species at Risk Act, SARA, protects species from extinction. However, Canadian citizens have a limited ability to hold their federal government legally accountable for this law’s enforcement. In the United States, we have the Endangered Species Act (ESA), one of the most powerful environmental laws in the world, because it directly prohibits what we can do to wildlife. US citizens dissatisfied with this law’s implementation can sue the government. However, the ESA is cumbersome and expensive to apply. For example, as of 2013 it had taken one and a half decades to create a lynx recovery plan, two decades to protect the wolverine, and four decades to fully protect the jaguar and create a recovery plan. While successes such as the wolf in the Northern Rocky Mountains (NRM) demonstrate that this law works, we have failures, such as the case of the Mexican gray wolf in the southwestern United States, which, due to illegal killing by humans, hasn’t reached the modest recovery threshold of 100 animals despite almost two decades of conservation efforts. Of all three nations, Mexico has the weakest environmental laws. But even there, people are making headway in conserving carnivores, such as the jaguar, with government support of private land stewardship. Tribal law sustains the rich cultural heritage and traditions of Canadian First Nations, US Native Americans, and Mexican indigenous people, via treaty rights and tribal sovereignty. However, these rights are far stronger in the US and Canada than in Mexico.
Q. How do different types of carnivores influence the ecosystems around them?
A. Large carnivores are showing us that their wildness serves a real ecological purpose. Large carnivores, which touch everything in the web of life, create biodiverse, healthy ecosystems. Richer in species, ecosystems that contain large carnivores will be more resilient to climate change, and therefore will better enable humans to live sustainably, capably, and happily on this planet.
Throughout the Carnivore Way, wolves, lynx, and other carnivores are teaching us about how rewilding nature by bringing them back from the brink of extinction is as necessary to the exchange of energy in food webs as the flow of soil nutrients. By creating trophic cascades—food web relationships in which apex predators affect their prey, which in turn affects prey food consumption—wolves and other apex predators increase ecosystem health. For example, lynx prey on snowshoe hares, which eat willows. By reducing snowshoe hare numbers, lynx indirectly create healthier willows, and these healthier willows can provide better habitat for songbirds. But in addition to actual, direct acts of predation, these predator–prey relationships can have indirect effects related to fear. In Glacier National Park, for example, fear of wolves makes elk more alert. To avoid getting attacked by wolves, elk must move around more and avoid spending time in aspen stands that have burned and become filled with deadfall. The downed trees in these burned stands make it difficult for elk to run to escape wolves. In Glacier, burned stands now contain thickets of aspen saplings growing vigorously above the reach of elk. Thus, together with fire, wolves are helping aspen flourish.
However, some carnivores, such as cougars, which are solitary and stealthy and can eat many different types of animals, do not have as strong of an apex predator signature in an ecosystem. Yet they are highly important members of an ecological community because of being predators. When cougars kill an animal, they eat their fill and typically cache the leftover meat to eat later. These carcasses end up providing a precious food resource to hundreds of other species—everything from golden eagles to weasels to insects.
Q. In the book, you share many of your own stories of interacting with large carnivores. Which of these is your favorite?
A. It’s really difficult to pick a favorite story, as over the years I’ve had so many powerful lessons about coexistence from the carnivores. However, as I was finishing writing my book, I received a “capstone” lesson from a bear in the Great Bear Rainforest in coastal British Columbia. One morning near dawn, I sat very close to a wild grizzly bear mother, watching her teach her tiny cub to fish for salmon. She kept catching salmon and passing them to her cub. And the cub kept dropping the fish. At one point the frustrated bear mother looked at me calmly, making eye contact with me, a classic “What’s a mother to do?” expression on her face. And in that moment the distinction between species was gone and we were just two mothers at a stream. She and the other bears in that rainforest taught me that there are still places on this Earth where humans and carnivores can just live in peace. Spending time with those bears at the height of the salmon run showed me how it once was, between humans and wild creatures sharp of tooth and claw, long before we thought we knew everything and could grow forests and elk like crops. While we can’t quite re-create the close relations that we may once have had with living things and that I experienced in the Great Bear Rainforest, we can envision a world in which we base our relationships with carnivores on respect and trust.
Q. What do you hope your readers take away from The Carnivore Way?
A. Science tells us that if we want to have a healthy world, we need to conserve the carnivores. Doing so necessitates creating a new model for coexistence. This means developing a contemporary land ethic, one that takes us beyond seeing wildlife as a crop or a renewable resource. This means envisioning a world in which we base our relationships with carnivores on respect, rather than fear, and where we allow them to fulfill their ecological roles as much as possible. To do so, we need to give them room to roam, so that their benefits can cascade through whole ecosystems.
Sharing this Earth with thriving, healthy carnivores comes down to coexistence. The problem is that coexistence means different things to different people. To some people, coexistence means keeping carnivore numbers as low as possible short of extermination, in order to produce more moose for hunting by humans. Conversely, some define coexistence as protecting every carnivore, completely and always. Realistically, in our fragmented, modern world, coexistence lies somewhere between these two perspectives. To create and support thriving populations of large carnivores in our rapidly changing world we need to learn to live more sustainably and ethically on the earth. While science and environmental laws can help us learn to share landscapes with fierce creatures, ultimately coexistence has to do with our human hearts. Editor's note: Our Rewilding Adventure sweepstakes with Cristina is almost over! Enter by March 22 to win a trip for two to Yellowstone National Park for her Carnivores and Corridors course.