On the trail of a wildlife enigma: Researchers study elusive wolverine

Through the deep snows of a Many Glacier winter and along the well-hiked Highline Trail, a team of dedicated scientists and volunteers is tracking one of Glacier National Park's enigmas: The wolverine.

With its low-density population, incessant travel across an expansive range, and reputation for ferocity - wildlife research biologists Jeff Copeland and Rick Yates prefer the term "tenacity" - the wolverine does not give up its secrets easily.

Copeland and Yates speak of the elusive member of the weasel family in superlatives.

"They are undaunted by time and space," said Yates, a Whitefish researcher who teamed up with Copeland after Glacier National Park commissioned the Rocky Mountain Research Station to do the study in 2001.

Wolverines live at the top of the world, making a living at the heights of formidable mountain ranges. Almost nonstop, these 25-pound athletes, give or take maybe 10 pounds depending on their sex and age, travel a territory that can range up to 300 or 400 square miles.

Copeland, Yates, Dr. Dan Savage (a Kalispell veterinarian and integral partner in the study) and Whitefish author and research volunteer Doug Chadwick still are not sure when the creatures rest.

"There's no other animal like that," Yates said. Wolves travel similarly "when they're dispersing, bears when they're on the move. But wolverines do that all the time."

It's one of the precious few facts that researchers have logged about a wolverine's life and its overall place in the ecosystem.

Glacier is one of the few national parks with wolverines, Copeland wrote in his study proposal, and it may have the highest-density population among park units. But, he postulated, human winter recreational use could affect their reproductive success.

If this source population is not protected, wolverines in the Northern Continental Divide Ecosystem could run the risk of returning to near-extinction levels seen after the government's eradication programs in the early 20th century.

The species has been little studied even in recent years.

"They're a large, important carnivore with very little contact with humans," Copeland said. "We pay attention to wolves because they eat our livestock. We pay attention to bears because they tip over our garbage and eat our livestock.

"But wolverines are very isolated; they don't come into contact with humans. They're pretty much off our radar screen."

As such, there's not enough information on the wolverine to even consider listing it with endangered or threatened status.

Researchers received National Park Service funding for a three-year study, "the short end of wolverine research," as Copeland described it. The expensive and time-consuming process to get a true picture of the animal in the wild easily could consume the better part of a decade.

Private funding from Grace Kirshner of Kalispell, the Glacier Fund, Earth Friends and others allowed extension of the study which - without additional funding - ends this spring.

Copeland devised a plan to track wolverines by fitting them with GPS satellite collars and abdominally implanted transmitters, adapted a log-cabin-like live trap, and enlisted a hardy core of helpers with backcountry skis and lots of stamina.

Building on information available from the only two studies done in the lower 48 states, he decided to focus on reproductive ecology.

Wolverines breed around June each year, with egg implantation delayed until mid-January. Six weeks later, the kits are born. By mid-May they are weaned.

Continual interference with denning in the winter could prove disastrous.

"Part of my work in the early 1990s in Idaho was on snow machines," Copeland said, "but we focused on the winter range. We thought we could just push snow machines into the high country and there would be no wolverine up there. But that is proving wrong. They're denning in the high country, not just in the alpine cirque.

"More important, from my perspective, is the issue of displacement," not just actual den disturbance, he said. "If you find a place you like to ski or snowmobile and you're up there all winter, that is likely to displace that female."

A displaced female may not implant a pregnancy. An insecure den also may mean kits that are born don't survive.

To learn how to protect the reproductive process, Copeland and Yates examined habitats females choose for denning.

They also acquiesced to a Glacier Park directive to include males in the study. Copeland is glad they did. Not only have males been seen watching over a maternal den, they have been tracked repeatedly in close contact with females and their young.

To date, 19 males and females have been fitted with collars and transmitters. They are monitored by telemetry and a system of 10 live traps, most in the eastern reaches of Glacier Park.

At virtually every turn, researchers have uncovered striking insights into a wolverine's life.

Take mountain goats, for example.

More than a decade ago Chadwick's seminal work, "A Beast the Color of Winter," included no mention of wolverines, although they tore into his campsite many times as he researched brutal winters.

But the Glacier Park wolverine study is revealing a strong connection.

"During the winter, the wolverine relies heavily on the goat for food," Copeland said. "We were always amazed at how these animals will cross the mountains in Glacier, going straight up incredible terrain. We're beginning to think there is some method to their madness."

Running on broad feet - "they're like snowshoes with a hell of a set of crampons on," Chadwick said - wolverines take the shortest line to the highest peaks.

"What mountaineers would consider climbing routes, they use all the time," Yates said.

Those high crags are precisely where mountain goats tend to live.

"They may be crossing there not just because they can, but to put themselves in a position to prey on them for food," Copeland said.

Chadwick had observed that mountain goats focus their attention on the rocks below them, so are easily surprised by things from above.

"If a wolverine gets above them, they have better chances of getting a kid or driving a goat off a cliff," Copeland said. Mountain-goat remains have been found inside the dens of all three denning females studied in Glacier Park to date.

One male, tagged M8 for this study, went beyond all definitions of "world-class runner."

After M8 was captured as a yearling in February 2004 and fitted with a transmitter, it headed to Hungry Horse, then to the Whitefish Range and Big Mountain by March. He disappeared in early April. In July, he was found in the Yaak.

Yates said researchers are pretty sure M8 somehow crossed Lake Kookanusa and was found at Rexford. By Christmas he was killed by a fur trapper.

And M8's monumental trek - 120 air miles - was undertaken as a subadult, long before the 3-year-old marker for adulthood.

Wolverines tend to live just below and just above the treeline, where there is a wide range of cover and rich species overlap.

The terrain gives them options, but it's their tenacity that assures survival: A visitor to Glacier Park's Hidden Lake overlook watched through his field scope as a wolverine defended a cache against a bear. In Sweden last summer, Yates saw a wolverine den with a brown bear skull that had been fed on.

Wolverines' circumpolar distribution has shrunk from their historic range that stretched as far south as the Black Sea in Russia to the American Southwest. Today, they're found in Finland, Sweden, Russia, Alaska, Canada and parts of surrounding lands.

In the United States, a smattering is found in Washington, Idaho, Montana, Wyoming - in short, where they have snow on June 1, Chadwick said.

A population study is starting in Yellowstone National Park, one has been completed in the Pioneer and Pintlar mountains, and researchers are checking the Sierra Madres and Northern Cascade Mountains for signs of wolverines.

Snow seems to be a critical component in den sites.

Dens are dug into the snow under brush and fallen logs. A notable number of those logs are whitebark pine, which suffered a 90 percent die-off from blister rust a few years back in Glacier Park.

"Glacier National Park is as good as it gets, and may be the key to their future survival," Chadwick said.

The researchers' tenacity nearly matches that of their subject.

"We get a wolverine in a trap, we call Dan and he skis five or six miles in at night," Chadwick said. "That's what makes it work."

They laughed over memories of Savage's first wolverine surgery, accomplished in pouring rain after a brutal ski trip to the trap and with Copeland urging him to hurry because they had no idea how long the anesthetic would last.

"Dan is very fast," Yates said. "We couldn't have done this study without him."

So why do they do it?

"For me, it all comes down to the determination of the critter," Yates said. He's impressed by their survival skills, by the way wolverines exploit the food pyramid. "It's a matter of environment."

For Savage, "Initially, it was about the excitement." That hasn't faded, but rather expanded.

"I got emotionally involved. I was blown away by the team approach" to this study, he said.

"I think it's important," said Yates, a 25-year veteran of wildlife studies in Glacier who saw a female wolverine and her kits before he ever spotted a bear. "Scientifically, it's a mystery. That's as good as it gets."

Reporter Nancy Kimball may be reached at 758-4483 or by e-mail at nkimball@dailyinterlake.com.