Tuesday, July 19, 2011

A long road for recovery of Washington's grizzlies and wolves


Guest columnist Paula MacKay celebrates recent documentation of a grizzly bear and a new wolf pack in the Washington's Cascade Mountains. Still, recovery of these animals has a long road of planning and commitment to change.
THE documentation of a rare grizzly bear in the North Cascades and a new wolf pack in the Teanaway is exciting news for our region, which has long played second fiddle to the Northern Rockies when it comes to carnivore recovery.
Indeed, the Cascades are perceived as the Rodney Dangerfield of mountain systems by some carnivore biologists in Washington, who lament that they "don't get no respect" in the shadow of Yellowstone and Glacier. At last, the North Cascades have staked their rightful claim as the other place in the lower 48 with a real opportunity to host the full suite of native top predators — including grizzlies and wolves.
It should come as no surprise that these icons of wildness would find home in the North Cascades Ecosystem (NCE), which comprises 24,800 square kilometers in Washington and an additional 10,350 square kilometers in British Columbia. The NCE also includes one of the largest contiguous blocks of federal land remaining in the continental U.S.
Wolves and grizzly bears wandered this big, wild landscape until they were decimated by trapping, hunting, poisoning and habitat loss during the 19th and 20th centuries. (Hudson Bay Company records reveal that 3,788 grizzly bear hides were shipped from trading posts in the North Cascades from 1827-1859 alone.) Ultimately, both species were eliminated from Washington and most of the lower 48, with grizzlies left occupying a mere 2 percent of their original range and wolves a meager 5 percent.
Today the journey for grizzlies and wolves in Washington has only just begun. It's one thing to root for a lone bear standing on a distant mountaintop or a pregnant wolf howling in her newfound wilderness, but quite another to make room for their long-term presence in a crowded world. The former is the stuff of a romantic nature film. The latter requires tolerance, big-picture planning, and a profound commitment to change.
Although the recent documentations are good cause for celebration, many salient questions remain. For example, why have wolves and grizzlies been so slow to recolonize the NCE, where big mountain wilderness awaits them?
The answer is no doubt a complex weave of ecological, political and economic factors, but this much is clear: If grizzlies and wolves are to be restored in viable numbers, we need to maintain and enhance habitat connectivity within the region and to populations outside of the region.
Large carnivores must be able to move safely through the landscape to expand their range; as wolves in Yellowstone have shown us, no place — not even a grand-scale national park — is an island. Those dispersing wolves that have returned to Washington from Idaho, Montana and British Columbia over the past few years traveled vast distances in search of new territory, no doubt encountering many obstacles along the way. Too little is known about the ancestry of our few remaining grizzly bears to speculate on their geographical origins, but suffice it to say their future will depend on newcomers as well.
One of the challenges we face in Washington's NCE is that this otherwise remote region is traversed by three major east-west highways: Interstate 90, and Highways 2 and 20. Although these highways experience varying degrees of traffic, they all represent potential barriers to carnivore movement in the Cascades.
Grizzlies are especially wary of busy roads, and both bears and wolves are vulnerable to human persecution when roads provide easy access. The Cascades Carnivore Connectivity Project — a unique collaboration between academic, government and nonprofit entities — is evaluating the barrier effects of these highways on American black bears and American martens. The results of this study will provide insights on grizzlies and wolves as well.
As one major step in the right direction, the Washington State Department of Transportation is taking extensive measures to enhance habitat connectivity across I-90 in the Snoqualmie Pass region, which bisects an important corridor for wildlife in the Cascades. The construction of wildlife overpasses and underpasses will help facilitate the safe passage of many species — perhaps someday including grizzlies and wolves. In Banff National Park, Alberta, these and other large carnivores are regularly documented using such structures to cross the Trans-Canada Highway. There's no reason it can't happen here, too.

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