Predator Management: What Africa can Teach Greater Yellowstone

Montanans like to brag about their world-class wildlife habitat. Scott Creel suggests they should expand their horizons.

“People who call Yellowstone Park the Serengeti of North America probably haven’t been to the Serengeti,” said Creel, a Montana State University ecologist who just published two research papers on large carnivore population dynamics in Africa. The difference goes beyond grizzly bears versus lions or elephants versus bison. His intercontinental experience shows that local human attitudes vary greatly in how to value and manage wildlife.

“We do have all the large mammals [in Greater Yellowstone] that were there at the end of the Pleistocene,” he said. “We have an ecosystem that’s amazingly intact compared to the rest of North America. They do contain all species, but they’re still heavily impacted by human actions.”

On the surface, it might seem that Zambia and the Greater Yellowstone Ecosystem have much in common. Their parks form powerful economic centers attracting tourists from around the world with accessible wildlife habitat. Wildlife outside those parks make both regions popular with big-game hunters and poachers. They both have human populations outside the park boundaries whose livelihoods often conflict with predators in those ecosystems. But Creel says conditions on the ground, both biologically and socially, differ greatly.

“The big, protected areas in Zambia are among the best functioning on the planet,” he said. “We have nothing in North America that looks anything like it. In North America, we’ve already lost almost everything.”

Creel has also done extensive science on wolf and elk populations in Yellowstone. There, he regularly encountered disagreements between how National Park Service and state wildlife agency policies and priorities drove management of creatures such as wolves and bison. The experience was so frustrating, he said, that he switched to Africa.

Creel and his colleagues have been researching wild dogs and lions in two Zambian national parks for more than a decade. South Luangwa National Park, where he did the lion work, comprises 2.2 million acres, about the same size as Yellowstone. Kafue National Park, at 5.4 million acres, is bigger than Yellowstone and Glacier national parks combined.

So by both geographical scale and population sizes, the Zambian ecosystems aren’t as close to tipping points as their Northern Rockies counterparts. Keystone predators such as grizzly bears and wolves cling to tiny fractions of their historic and evolutionary range in North America, and have required decades of government protection to avoid complete extinction in the Lower 48. Opponents of those recovery efforts seek new ways to further reduce predator numbers. 

“There are about 1,600 wolves in the entire Northern Rockies,” Creel said. “That’s not an ecological carrying capacity. They level out at 1,600 because if their numbers get above a certain level, we kill them at higher rates. We’re controlling what the level of tolerance is for wolves. In places like Zambia, species are actually at ecological carrying capacity. That is quite different in my opinion.”

He credited some of that attitude to the greater experience people in Zambia have dealing with wild carnivores. They see lions routinely as they travel by foot or on bike, and often lose livestock to predators.

“In Africa, it’s far less polarized,” Creel said. “More people see both sides of the equation. They see issues of conflict, and also see the value of the animals. The polarization of the issue is much lower, which is one of the things I like about working there.”

Creel’s wild dog study has run since 2013. These pack hunters, each about the size of a German shepherd, have spent most of their existence ecologically restrained from above by hyenas (which steal their prey) and lions (which kill them).

“We used to think there’s always enough food,” Creel said. “That’s not going to hold [wild dog] numbers down. Now we’re finding prey depletion is holding them down. We do need to worry about that.”

Populations of wildebeest and impala, for example, have been crashing across sub-Saharan Africa, mainly because of habitat loss and poaching. Bushmeat poaching by poor people killing wildlife for food and income has been a particular problem. Creel said the prey species populations are between six and 20 times lower than they could be as a result of poaching.

Illegal hunting was also an issue for lions, but in a more positive direction. Creel’s fellow carnivore biologists had observed lion populations falling by 3 percent a year in the early half of the study. They debated tactics to reverse the trend. The method that showed the most impact was increased anti-poaching patrols to protect prey species.

“When extra protection was imposed for lions, it worked — the numbers began increasing in a short period of time,” Creel said. “The survival of adults didn’t change. It was the reproductive rate that changed with better access to food.”

Well-fed female lions went from having litters of three cubs to litters of four, resulting in an overall 29 percent increase in cub production. The elimination of snares in the patrolled areas also reduced the number of adult lions getting killed. But more important, the researchers found, was that fewer prey species were dying in the snares. In study areas without the anti-poaching patrols, lion populations kept declining.

Creel said one thing he appreciated about wildlife management in Zambia was its straightforward focus on balancing human and wildlife interests. More than 70 percent of Creel’s research team is Zambian, either academic or government-agency biologists and field agents. And they were able to conduct studies with near laboratory levels of control. 

For example, the lion study involved applying anti-poaching patrols to some parts of a park but not others, and then comparing the results. Lion populations in the protected areas grew about 8 percent annually, while those in unprotected areas continued to decline.

“They say ‘Go get the data that are needed to guide the policy, and see what you find,’” Creel said of the wildlife managers in Zambia. “We come back and say here’s what we did and what we can do. And when we get results, they’re immediately inside the agency charged with managing wildlife.”

In contrast, predator management in the United States seems driven by attitudes rather than analysis.

“Do wolves kill livestock? Yes they do,” Creel said. “But are they a fraction of 1 percent of the total losses. Yet if you listen to the [public] argument, you’d think it was half of it. I’m not sure how far a quantitative argument goes.

“Here [in Greater Yellowstone], carnivores are just another example of things caught up in culture wars. The idea that I can provide new data that will change a person’s mind —  I don’t think happens much. In Africa, it’s still very effective. I can move the needle more effectively by providing information. Sometimes in North America it feels like more information doesn’t matter at all.”