The wolverines that float on snow

Eight-year tracking programme reveals more about mysterious species

December 2011: Born during February in snow-caves at 9,000 feet on the north slope of craggy peaks in the Rocky Mountains, Yellowstone's wolverines are tough.

Now experts at the Wildlife Conservation Society (WCS) are revealing more about this mysterious and awe-inspiring species.

Eight years of capturing and radio-tracking the elusive wolverine revealed that adults live year-round in the high mountains, near the alpine tree-line, and inhabit some of the west's most remote and rugged terrain. Amazingly, the home range of an individual male can more than 500 square miles.

The winter endurance athletes of the animal world
‘Not only do they use an area even larger than a grizzly bear does,' said Kurt Alt, a coauthor with Montana Department of Fish, Wildlife and Parks, ‘they cover their territory on a fairly regular basis to scent mark it and defend it from other wolverines.'

The wolverine's capability for movement is stunning. Their large feet allow them to float on top of deep snow, and they were documented making winter traverses from one side of the massive Teton Range in Wyoming to the other in just a few hours.

‘They are the winter endurance athletes of the animal world,' said Steve Cain of the National Park Service. ‘We were impressed by their constant movements across large areas of snow-covered and incredibly rugged terrain.'

But covering this terrain comes with its risks, as two of the radio-collared wolverines were killed in avalanches.

One wolverine travelled more than 500 miles
Another wolverine travelled more than 500 miles from near Grand Teton National Park in northwest Wyoming to Rocky Mountain National Park in Colorado. This was the first documented wolverine in Colorado in almost a century. Other young wolverines regularly moved 100 miles or more searching for their own territory.

While bears are hibernating and most ungulates and their predators have moved to low elevation wintering ranges, the wolverine patrols a vast, frozen territory, looking for scraps of meat that they cache under boulders and snow.'

‘We learned that wolverines are adapted to eke out a living in very harsh conditions,' said Robert Inman, conservationist for the WCS. ‘As a result, they naturally exist in low numbers and reproduce slowly.'

The wolverine's reputation as a fierce competitor was also affirmed during the study. One individual challenged a bear probably ten times his size over an elk carcass.


http://www.wildlifeextra.com/go/news/wolverine-yellowstone.html

Island wolverine 'may still be around' (via Chad Arment)

Somewhere in the mountainous wilds of Vancouver Island there may be a few remaining wolverines belonging to a unique sub-species, a leading wildlife biologist believes.

Officially, the gulo gulo Vancouverensis - defined as the gluttonous glutton wolverine from Vancouver Island - almost disappeared in the 1960s and the last known sighting was in 1992, leading scientists to believe the species had been extirpated from the Island.

"But there may still be some around," said Montanabased Doug Chadwick, a National Geographic explorer and author of The Wolverine Way, who, hosted by the Sierra Club of B.C, was due to give a talk and slideshow Tuesday night at Fernwood Community Association.

Chadwick knows how elusive wolverines can be, despite their ferocious reputation, which is why no one knows how many remain in the U.S and Canada. For decades the animals were trapped, poisoned and shot without governments keeping count and now it is believed wolverines could be endangered.
It is not even known whether the Vancouver Island group is a true sub-species, said Chadwick, who is hoping someone has a few pelts stuffed away in their basement which could provide enough DNA for testing.

"Today we would be able to do genetic testing to give a much surer sense of the difference," he said.
After studying wolverines in Glacier National Park, Montana, where the animals often cross the border to B.C.'s Flathead River Valley, Chadwick is convinced that much of their fearsome reputation is a bad rap. "They are seen as Tasmanian devils on crack. They are if you corner them or are competing for a carcass," he said.

Although wolverines will take on grizzly bears or wolves, there is no record of attacks on humans, he said. But, there is no doubt wolverines have a bad-ass attitude, Chadwick said. "They are designed to intimidate so they can compete with grizzly bears," he said.


Read more: http://www.timescolonist.com/technology/Island+wolverine+still+around/5572593/story.html#ixzz1bhOcNHdZ

By Judith Lavoie, Times Colonist
http://www.timescolonist.com/technology/Island+wolverine+still+around/5572593/story.html

Michigan's lone wild wolverine found dead

March 15. 2010 6:42PM
Karen Bouffard / Detroit News Lansing Bureau

Michigan's only known wild wolverine was found dead in a Sanilac County bog Saturday, according to state Department of Natural Resources and Environment officials.

The female wolverine, which was found in the Minden City State Game Area where it was discovered six years ago, is believed to have died of natural causes, spokeswoman Mary Dettloff said.

The brown furry mammal was spotted alive in late January by Deckerville High School teacher Jeff Ford, who was retrieving photos from a trail camera he'd mounted in the game area hoping for just such a shot.


"She came within 20 yards and circled around me," Ford said of the 28-pound creature. "Her claws were about an inch long and attached to a foot that's about the same size as a human hand.

"I was trying to stay still and be quiet but I was having a hard time because I was breathing heavily and shaking. When she got downwind of me she stopped ... and I got out of there as quick as I could."

It's been centuries since wolverines last made their home in the state, and DNR officials suspect this one may have been imported and released into the wild.

"The last one in Michigan in the wild was probably 200 years ago," Dettloff said. "We've long suspected that someone probably released it here. They do have them in Canada."

The animal's body was discovered by hikers. A necropsy will be performed at a DNRE lab at Michigan State University to confirm the cause of death, Dettloff said. The department plans to preserve the body for display at the Bay City State Game Area.

While Michigan's unofficial nickname is the "Wolverine State," historians aren't sure whether the animal ever inhabited Michigan.

According to the DNR's Web site, evidence shows if wolverines ever lived in Michigan, they would have been rare. The department offers theories for how the name was coined.

Some historians believe Ohioans came up with it as an insult around 1835. Apparently they believed Michiganians were as vicious and bloodthirsty as wolverines.

Another theory is the nickname was bestowed by Native Americans during the 1830s, for equally unpleasant reasons. According to that story, native tribesmen likened settlers' seizure of their lands to the gluttony of wolverines devouring their prey.

From The Detroit News: http://www.detnews.com/article/20100315/METRO/3150409/1361/Michigan-s-lone-wild-wolverine-found-dead#ixzz0ipZI6xZy
(Submitted by Chad Arment)

Climate change causes wolverine decline across Canada

Wednesday, 3 February 2010

By Matt Walker
Editor, Earth News

The wolverine, a predator renowned for its strength and tenacious character, may be slowly melting away along with the snowpack upon which it lives.

Research shows wolverine numbers are falling across North America. Their decline has been linked to less snow settling as a result of climate change.

The study is the first to show a decline in the abundance of any land species due to vanishing snowpack.

Details of the wolverine's decline are published in Population Ecology.

The wolverine lives in boreal forest across Scandinavia, northern Russia, northern China, Mongolia and North America, where it ranges mostly across six provinces or territories of western Canada.

This largest member of the weasel family eats carrion and food it hunts itself, including hares, marmots, smaller rodents and young or weakened ungulates.

It has evolved for life on the snowpack, having thick fur and outsized feet that help it move across and hunt on snow.

Striking trend

Wildlife biologist Dr Jedediah Brodie of the University of Montana, in Missoula, US, wondered how climate change might be having an impact on snowpack levels, and on the animals that depend on it.

He had previously researched how declining levels of snow in the US Yellowstone National Park, caused by climate change, was changing the abundance of aspen trees and how elk feed on them.

Dr Brodie and his colleague, Professor Eric Post of Pennsylvania State University, at University Park, US, gathered data on snowpack levels across six provinces or territories of Canada: Alberta, British Columbia, Manitoba, the Northwest Territories, Saskatchewan and the Yukon Territory.

In all bar the Yukon, he found that snowpack depth declined significantly between 1968 and 2004.

Other studies have shown corresponding rising temperatures and declining precipitation across much of the western US.

"It occurred to me that a good first place to look for ecological impacts of that snowpack decline would be with a snow-adapted species like the wolverine," Dr Brodie told the BBC.

"Fortuitously, Canada has good records of both snowpack trends over time as well as trends in the harvest of all sorts of fur-bearing animals."

So Dr Brodie and Professor Post examined the records of wolverine numbers caught by fur trappers over the same period.

They found a striking correlation between declining snowpack and falling numbers of the predator.

"In provinces where winter snowpack levels are declining fastest, wolverine populations tend to be declining most rapidly," the researchers wrote in the journal article.

"Spring snowpack also appears to influence wolverine population dynamics."

The researchers found only one territory, the Northwest Territories, where wolverine numbers are increasing. There, snowpack levels are declining but they remain much higher and less variable than in most other provinces.

Food scarcity

Dr Brodie cannot be sure why wolverine numbers are falling, but he has his suspicions.

"Recent work shows that wolverines appear to use areas with deep snowpack for dispersal. So reduced snowpack could make dispersal more difficult or dangerous, potentially reducing the success rate with which individuals can establish new home ranges," he says.

"Reduced snowpack may also make it harder for wolverines to get food, for several reasons.

"First, harsh winters and deep snow are major causes of mortality for ungulates like elk, moose, deer and caribou.

"If milder winters mean that fewer of these animals die over the course of the winter, then there will be fewer carcasses for wolverines to feed on," he explains.

"Wolverines also hunt rodents, and this food source may be important for wolverine reproductive success in some areas.

"But shallower snowpack is bad for a lot of rodents because it provides less insulation from the cold.

"So if declining snowpack reduces rodent abundance, that could be bad for wolverines."

Dr Brodie believes that his is the first study to show a decline in species abundance due to a reducing snowpack - for any land animal, not just those in North America.

But he says there are interesting parallels in marine systems.

"For example, sea ice is critical for polar bear foraging."

Polar bear body condition, reproductive rates, and survival have declined significantly in Hudson Bay as sea ice breaks up earlier in the spring, he says.

"At the other end of the globe, Antarctic sea ice has increased over recent decades.

"This may have negative impacts on adelie penguin populations that depend on ice-free areas for breeding and foraging.

"But we don't have to just sit back and watch climate change drive animals extinct," he says.

"As climate change worsens, we should reduce trapping levels and also disturbance to boreal forest habitats.

"Reducing the impact of these anthropogenic stressors could help 'offset' the impacts of climate change on wolverines."

http://news.bbc.co.uk/earth/hi/earth_news/newsid_8494000/8494397.stm
(Submitted by Lindsay Selby)