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Down to Earth: Tim Preso on Wildlife of the Crown of the Continent

Earthjustice attorney Tim Preso talks about protecting endangered species like the wolverine in the Crown of the Continent—one of the last remaining wild places in North America.

Length: 11 min 33 sec

Recorded: March 2011

[ Download MP3 ]

Earthjustice Attorney Tim Preso speaks with Earthjustice staffer Jessica Knoblauch.

Over the past decade, Preso has worked to protect endangered species that reside in the Crown of the Continent ecosystem. This relatively untouched wilderness is home to some of America's last iconic creatures, such as wolves, grizzly bears and wolverines.

Jessica Knoblauch: So Earthjustice is working to protect some of the threatened species in the Crown and elsewhere in the northern Rockies. Wolverines, for example, were considered endangered by the U.S. Fish and Wildlife Service, but due to a backlog of other species awaiting protection, they're still not quite being protected, is that correct?

Tim Preso: That's right. The Fish and Wildlife Service determined that although the species qualifies for listing under the Endangered Species Act that they were going to put it basically in administrative limbo and not take action to actually list it because they want to work on other issues and other species. And obviously we're not satisfied with that result and we're continuing to examine ways to move the wolverine up to the top of the list and actually get it listed under the Endangered Species Act.

But as to that issue, I think it's important to look back over the 10 years of work we've done on the wolverine species. First of all, the wolverine is the largest terrestrial member of the weasel family. It's a large, kind of bear cub-sized, extremely tough and ferocious wilderness species. I mean, really the wolverine only persists in places that are really and truly wild. The Crown of the Continent, which encompasses Glacier National Park in the United States and Waterton National Park in Canada, as well as the Bob Marshall Wilderness Complex, is one of the largest undeveloped landscapes remaining in our country. And the Crown of the Continent is really the stronghold for wolverines in the lower-48 states. That's the last place that they're remaining in any significant numbers.

There are a number of things that prompted us to focus on that species. One is just that it's really an amazing creature and it has a lot of amazing characteristics that just make it a particularly cool animal to work on. Wolverines are extremely tough and they live in extremely harsh environments at high elevation. Mostly they're up on those high ridges and they're up there year round. So when grizzly bears, which we think of as a tough animal, are sleeping in their hibernation dens for the winter, the wolverine is still out there on those snow-blasted slopes trying to eek out a living on mountain goats and bighorn sheep that get killed by avalanches and scavenge on carrion, but also they do take animals opportunistically and actually prey on other smaller species when the opportunity arises.

It takes a tremendously large landscape for them to find enough food to stay alive and so these animals have extremely large home ranges. Wolverines in Montana in the Glacier area, which has some of the smaller ranges because it's protected landscape, the males have a home range of a 160 square miles. So you can imagine this is an animal out there in the dead of winter when the wind is howling and the snow is just covering this landscape, covering 160 square miles over some of the most rugged country in the lower 48 states to make a living.

One anecdote from Glacier [National] Park talked about one wolverine that they released from a trap with a radio monitor on scaling basically a vertical shaft on a ridgeline that's called the Iceberg Notch, about a 1500 feet vertical climb. He scaled it in 20 minutes and popped over the ridgeline and was gone. So, they're just really kind of an amazing critter. But also they're a species that really is a living symbol of the wilderness. If the place is not sufficiently wild, there will not be wolverines there. So the presence of the wolverine tells us that the landscape is productive not only for the wolverine but for lots of other creatures that also require that kind of landscape: the fish, smaller mammals and ultimately us, who need clean water and places to get away from industrial society from time to time as well.

"The wolverine only persists in places that are really and truly wild … they're a species that really is a living symbol of the wilderness." (Gerald and Buff Corsi / CAS)

And then last the wolverine is really a canary in the coal mine on the impacts of climate change. We think about the polar bear when we think about the poster child for climate change and that's appropriate. But also the wolverine is unfortunately in the same boat. A pregnant female wolverine dens in snow in the spring period in the Rocky Mountain region. And so they tunnel into the snow in the spring and give birth to the kits and raise those kits in a series of snow tunnels. So they're really dependent on areas that have maintained snow pack into the spring period and really into mid-May. And increasingly in the Rocky Mountains that's a dwindling landscape because we're having these warmer winters and warmer springs and the landscape that's available for these animals to carry on their reproductive denning is shrinking. So right now the scientists believe that climate change is the single greatest threat to the wolverine.

But when we started this campaign 10 years ago we brought our first case to try to force the protection of the species. Montana had an unlimited trapping season. And so, Montana was losing about 10 wolverines a year. Over the course of our work, the pressure of our advocacy has caused a number of conservation measures to be put in place. Now Montana allows only five wolverines to be trapped annually so we've cut the trapping mortality in half. And it imposes limits particularly on female mortality, which is extremely important for a slow-reproducing species like the wolverine.

We've also focused on trying to remove disturbances from some of the most important parts of the wolverine's range. One of things that scientists who have studied wolverines have observed time and again is that female wolverines do not like to have human disturbance or any kind of disturbance in their denning area where they have their kits. They're very sensitive about any disturbance there, probably because there are some species that will go in and try to kill the kits in the den. So if a snowmobile comes blasting through a wolverine denning area, that's a huge disturbance. And typically the wolverine will either abandon the area or move the kits to another site. All of those things are extremely costly to a species that's probably living on chewing up bones that are left from a mountain goat carcass that was killed in an avalanche by that time of year.

Grizzly bears, like wolverines and lynxes, are a wide-ranging species that must cover a lot of area in order to meet their dietary needs. (Forest Service)

So we have focused on some of this vehicle planning in the national forest and we've succeeded in having a major reduction in snowmobile use in the wolverine range in an area north of Yellowstone National Park called the Gallatin Range. And we have succeeded in cutting way back on helicopter skiing activity in an area south of Jackson Hole, Wyoming called the Palisades Range, which is also an important area for wolverine range expansion. And so we've had some successes in trying to address the threats to the wolverines' continued survival.

The Fish and Wildlife Service estimates that the entire lower-48 population is about 250 individuals. In all of Glacier [National] Park, the scientists who have been studying the wolverine for the past decade or so think that there are approximately 20 to 25 animals. So when you start about taking 10 animals out of the population every year, it's going to have a very significant impact on the overall population.

By keeping advocacy for the listing front and center and the pressure on to protect the species it's provided a lot of resources for scientific research. We're now at a position where 10 years ago the Fish and Wildlife Service said we couldn't possibly protect the wolverine because we don't know anything about it. Over 10 years we've seen this body of scientific evidence emerge where now the Fish and Wildlife Service says, yes, we does know about this species. And yes, it is threatened. And now we just need to get the last step over the hurdle to actually get it listed.

Jessica: And to go to another species that Earthjustice has been working on for a long time on protecting, the gray wolf has also been a very long battle for Earthjustice.

Once you've protected a place that can host a grizzly bear … you have protected a place that can host all kinds of smaller, less well-known species that are part of the broader ecosystem and that will produce the kinds of things like clean air and clean water that we all depend on. So for us those are key decisions that we made a long time ago, and they're long-term commitments that we're not backing off from.

Tim: Well, when we're talking about the Crown of the Continent, the first place that wolves re-colonized the lower-48, way back 20 some years ago, was the northern Flathead Valley in Glacier National Park. So after the complete eradication of wolves from the lower-48 due to trapping and poisoning earlier in the 20th century, when finally wolves managed to be in a toehold in the lower-48 again, it was through natural recolonization on the western border of the Crown of the Continent.

Jessica: With so many issues affecting the Crown, how does Earthjustice decide which cases to take on?

Tim: Our motto is always, the biggest, most significant, natural resources controversies are the ones that we want to be in the middle of because we think we can make a difference in helping ensure an appropriate outcome. Once you've protected a place that can host a grizzly bear or a wolf, you have protected a place that can host all kinds of smaller, less well-known species that are part of the broader ecosystem and that will produce the kinds of things like clean air and clean water that we all depend on. So for us those are key decisions that we made a long time ago, and they're long-term commitments that we're not backing off from.

In order to protect a place like the Crown of the Continent, there's not just one case you bring to accomplish that goal. It's something that is an ongoing process. It requires a lot of work in a number of different places and often smaller scale battles that add up to a long-term protection for this irreplaceable landscape.

Images from the Crown of the Continent: One of the largest—and last—remaining wild places in North America, the Crown of the Continent ecosystem is a ten-million acre expanse of land whose untouched wilderness harkens back to the days of Lewis & Clark. View photos taken by conservationist Gene Sentz, who has spent three decades working to protect the Rocky Mountain Front.

Interactive Feature: Species Worth Protecting: A combination of U.S. Forest Service lands, national parks, tribal territories and private property, the Crown of the Continent links western Montana with southern Canada, encompassing some of the largest blocks of wilderness in the contiguous United States. As a fully functioning ecosystem, the Crown is home to nearly all of North America's large mammals.

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