Circumstances Force National Park Service to Actively Manage Wildlife

Wild they may be, but Yellowstone's bison will be managed to varying extents. Kurt Repanshek photo.

Florida panther kittens at Big Cypress National Preserve dosed with dewormers. Black-footed ferrets at Badlands National Park inoculated against plague. Sterilizing horses at Cape Lookout National Seashore and elk at Rocky Mountain National Park. And now Yellowstone National Park bison that could be vaccinated against brucellosis via air gun.

These are just some examples of how the National Park Service has taken a somewhat more active, hands-on role in managing its wildlife. To be sure, the agency almost from the beginning back in 1916 has actively managed the wildlife that fell within the park system's borders. Predators such as wolves and coyotes were killed, "favored species, such as bison, bears, and game fish" were nurtured, points out Richard West Sellars in his book, Preserving Nature in The National Parks, A History.

“There’s been human intervention for purposes of public enjoyment, not for species survival or more ecological goals," Mr. Sellars said the other day. "I’d say from the get-go they’ve been managing species.”

But these days Park Service biologists are wielding a higher-tech set of tools to vaccinate, inoculate, and, in some cases, sterilize species all in the name of wildlife management. The field veterinary work can seem contrary to the agency's mission to let natural processes play out. But circumstances, both political and biological, that largely are beyond the agency's control are forcing its biologists to manage some species almost like zookeepers manage theirs.

In the case of Florida panthers in Big Cypress and black-footed ferrets in Badlands, the species are bordering on extinction. In Yellowstone, bison that might be carrying brucellosis, which can lead to spontaneous abortions in livestock, are the victims of politics and economics. The elk in Rocky Mountain, meanwhile, lack an apex predator to keep their numbers in check, while sterilization of feral horses at Cape Lookout is done in the name of genetic manipulation for healthy stock.

In the years ahead, more and more park biologists might seem more like zoo veterinarians, actively managing their wildlife to sustain their populations.

“I don’t see how we can not consider active management of diseases," says Dr. Margaret Wild, a wildlife veterinarian who leads the Park Service's Wildlife Health Program out of the agency's Fort Collins, Colorado, office. "Of course, it has to go through all the park planning and approval processes. But to think that these parks are fully functioning ecosystems, it’s just not true for the vast majority of our national parks, at least in the Lower 48 states.

"These are wild locations, but with a lot of human influence, whether it be from lack of predators, from interactions with domestic animals, spread of disease from domestic animals to wildlife," she said. "And then the concern of the spread of those diseases from wildlife back into domestic animals. There’s too many human influences to think that we can just be completely hands off in most of our national parks.”

Yellowstone is a perfect example of where almost a century ago livestock transmitted a disease, brucellosis, to bison and elk, and where now there's concern about the wildlife reinfecting later generations of cattle in Montana. Though there's no known case of the disease being spread from bison to cattle, Montana's livestock industry has succeeded in forcing the Park Service's hand to tamp down whatever tendrils of the disease might exist in Yellowstone's bison.

Dr. Marty Zaluski, the state veternarian for the Montana Department of Livestock, said there has been no documented case of brucellosis transmission from bison to cattle in large part due to ongoing efforts to keep the two separated.

“The livestock community has recognized the risk of brucellosis transmission from bison to livestock for decades, and so there has been separation, and they are easily recognizable on the landscape, bison are," said Dr. Zaluksy. "So therefore we have been successful in maintaining that operation, or that separation, and we’re victims of our own success. To this point we’ve been successful in mitigating the risk and people say there is no risk."

But while that separation has been successful, Montana officials still want Yellowstone to develop a vaccine that it can use on its bison herds.

"You need to try to maintain separation on the bison side, you need to have this temporal and spatial relationship," the state veterinarian said. "And you know, to be quite honest, the vaccination of bison for brucellosis through the remote vaccination is another tool in our toolbox.”

Not every wildlife disease-related problem gets such attention, though. Yellowstone's wolf packs have struggled at times with distemper, but biologists didn't rush out with bio-darts to inoculate them, in part because it would be impractical, in part because the overall wolf population wasn't in danger, and in part because there were no great concerns of them spreading the disease outside the park. The spread of brucellosis, though, into cattle herds in either Montana or Wyoming could have dire consequences for ranchers, and the Park Service has to keep that in mind, said Dr. Wild.

"We have to not just think about what’s prudent and feasible for our wildlife, but we have to consider our neighbors," she said. "And that’s what the Interagency Bison Management Plan was about, and vaccinations was one of the alternatives that was identified there.

"...The Interagency Bison Management Plan recognizes the importance of free-ranging bison, and also recognizes the importance of the cattle industry to Montana. So we have to think about our neighbors, but put that into the context of always staying within our policies and doing things that are within our policies," added Dr. Wild. "But when we can do those things that are within our policies, and also be more helpful to our neighbors, we know the best available science tells us we’re not going to have a negative impact ... then that’s when I would say it becomes prudent and feasible to do that.”

As for the attention being paid to Florida panthers and black-footed ferrets, the Park Service veterinarian said such a hands-on approach is justified because those are quite possibly the two most-endangered mammals in North America.

"Those are both highly endangered species that are more intensively managed than your typical species. Much more intensively managed," Dr. Wild said. "At Big Cypress they try to keep as much of the population collared as they can. They do really good monitoring of those animals, and they probably know a fair number of the den sites. They can get in there and treat the kittens. Would you do this with mountain lions in the Western U.S.? No. But for that highly endangered species does that makes sense, where if you can help one kitten survive, and it will have a large impact on the percentage of Florida panthers than you might have in the wild ... then yeah, helping one kitten survive can really help."

As for the ferrets at Badlands National Park, a multi-agency desire to "protect one-third of the highest quality black-footed ferret habitat in an effort to protect two-thirds of the black-footed population in the Conata Basin/Badlands National Park ecosystem" has led to a highly managed ferret population. The appearance of plague in the colonies of prairie dogs, which are the ferrets' main prey, in recent years has led to both the treatment of 11,000 acres of the park with an insecticide and to the vaccination of some ferrets.

"Of course as a veterinarian you’re initially thinking, or always got to be thinking as your basis, above all do no harm," explained Dr. Wild. "So, we’re very cautious with the vaccines that we use. We know for example the canine distemper virus, in addition to plague, was one of the factors that almost pushed black-footed ferrets into extinction. So now the ferrets are also vaccinated with canine distemper vaccine."

As she noted earlier, Dr. Wild envisions a more active approach to wildlife management by the Park Service, not a lesser one due to shrinking wildlife habitats and cooridors.

“Would it be great if we had these functioning ecosystems and we could just say, 'Yeah, we can do passive management, or no management and just take a hands off approach'? Yeah, that’d be ideal," she said, "but I just don’t see those (approaches) in the systems we’re dealing with.”

To Mr. Sellers, who spent three decades working for the Park Service, the need for such aggressive management concerns him a bit.

"Yet the attitudes towards the parks, the hostile attitudes that you often see, and the indifference towards certain species ... I think we're locked into intensive care to certain species," he said, adding that there are "thousands" of other species that are given comparatively little attention.

"I think it’s the nature of the game and I don’t believe we’ll ever escape from it,” said Mr. Sellars.