Wolverines, Grizzly Bears, and the Natural Power of Connections - Notes from the Dec 2013 Holiday Program

Doug Chadwick by Karen Reeves

By Volunteer Bob Herbert

The Methow Conservancy's December program was standing room only for the biologist and author Doug Chadwick.  Doug traveled from his home outside Glacier National Park and he shared with us his vast knowledge about two of North America’s fiercest predators.  Doug is an expert on wolverines and grizzlies, and the photographs and stories he shared were enthralling.  Both creatures play an important role in the food chain, and they both provide balance to the pristine Rocky Mountain wilderness they call home.  They live on the crown of the continent, and Doug showed us that the wolverine prefers the crests to the valleys, and they summit the tallest peaks before breakfast.

             

Chadwick & "Tank" snarling by Joel Sartore

There is approximately one grizzly bear for every five square miles, and they and the wolves are known as ‘keystone species.’  The Northern Rocky Mountains boast the largest and densest population of grizzlies on the planet.  The berries the bears eat are returned to the ecosystem in the form of fertilizer and seed, which insures a constant source of food for these magnificent creatures.  The digging bears do in order to find grubs helps to turn the soil over, which is why Doug referred to them as the gardeners of the mountains.  These bears are survivors and they are capable of living in extreme conditions.  We learned that there are thirty grizzlies that still remain in the harsh, arid climate of the Gobi desert. 

Wolverine by Steven Gnam

The grizzly bear is a powerful creature and it symbolizes the rugged wilderness of North America, but the stories Doug shared about the wolverine kept the audience’s jaws open in awe and utter respect for this elusive creature.  The wolverine hales from the same family as weasels and martins and they reside in the alpine and sub-alpine regions of North America.  They grow to around three feet in length and they weigh thirty pounds at maturity.  They have been known to take down moose and caribou, and they are fierce enough to drive grizzly bears off of a carcass.  They travel the most difficult routes possible, over the highest peaks in the area.  They travel straight up avalanche chutes and down the backside of mountains at a speed that is unattained by any other creature, and they do it with the endurance necessary to evade any predator.  One GPS tracking device showed how a wolverine climbed a vertical mile to the summit of a mountain and back down to the next valley in ninety minutes.  They did this in the middle of winter with heavy snow on the mountain.  For any Methow locals who would like to test their endurance and speed against the wolverine, you can replicate this feat by starting at the base of Last Chance Point, attaining the summit, and returning to the road that leads to Hart’s Pass in 90 minutes, in snowshoes, in February.

Captive wolverines by Dale Pedersen

Wolverine by Steven Gnam

Wolverines will dig through 20 feet of snow in order to find a marmot sleeping in a den.  They dig their own den in 10-12 feet of snow, and they will tunnel 20-50 feet horizontally, which is why global warming is threatening this rare species.  The only real competition the wolverine has for food is bacteria, and they have been known to return to cached food tens of miles away, months after the kill, in order to find a meal during the harsh winter months.  Wolverines will not tolerate temperatures over 70 degrees, which is why they make their homes in the most remote, glacier covered mountains of North America.  There were 110 glaciers in Glacier National Park when it was founded in 1910, but there are only 23 that remain today.  The reduction of possible den sites and feeding grounds means that wolverine habitat is disappearing faster than any other species in that ecosystem.  There is an estimated 35-45 wolverines living in an area that covers 1,500 square miles.  The same area contains approximately 150 grizzlies, so you can see how rare the wolverine really is.  The wolverine’s territory covers 200 square miles of the most rugged landscape on the continent, and it is estimated that only 300 remain in the lower 48 states.   

Thank you to Doug for sharing his knowledge, expertise, and humor with us. and thanks to the Methow Conservancy for bringing him here.  I’m sure that everyone who attended gained a healthy respect for the wolverine and the grizzly bear, and we are lucky enough to have a small wolverine population living in our side yard in the North Cascades.