A member of his research team called from a site high in the northern Cascade Range of Washington to report that a wolverine had just been captured. Aubry, a carnivore expert and research wildlife biologist at the U.S. Forest Service Pacific Northwest Research Station in Olympia, Wash., and Jeff Copeland, a wolverine researcher with the Rocky Mountain Research Station in Missoula, Mont., rushed to the Methow Valley to fit the young female wolverine with a satellite radio collar to initiate the first scientific study of wolverines ever conducted in the Pacific Northwest.
Other members of the interagency team, including wildlife biologists John Rohrer of the Okanogan-Wenatchee National Forest and Scott Fitkin of the Washington Department of Fish and Wildlife (WDFW), traveled by snowmobile to a remote location south of the Pasayten Wilderness in Okanogan County. After immobilizing the wolverine with a sedative, Aubry and his team quickly went to work to evaluate the health of the animal, take measurements and tissue samples for genetic analyses, and install a radio collar to report her movements to Aubry via satellite for the next 18 months. "With this technology, we can now begin to gather reliable information on the movements, home range, and habitat of wolverines in the Pacific Northwest," said Aubry.
The wolverine is a Federal Sensitive Species and a Washington State Candidate Species for protective listing. Since the mid-1990s, biologists have documented the presence of wolverines in north-central Washington via aerial surveys, remote cameras, and winter tracking.
"What we learn about wolverines from this effort will help us determine the species' status and management needs," said Ro hrer, who is the project field coordinator for the Methow Valley Ranger District in Winthrop.
The capture is the culmination of several years of survey work in north-central Washington to document wolverine presence to begin to understand their habitat needs. "We know so little about these rarely seen animals that this is an exciting opportunity to learn more about their general ecology in the north Cascades," said Fitkin of WDFW.
Wolverines (Gulo gulo) weigh about 20 to 40 pounds, depending on sex and age, and are the largest land-based member of the mustelid family that includes weasels, badgers, and otters. They are primarily found in boreal forest and tundra habitats in the far north, but also occur in mountainous terrain at the southern end of their current range in the Cascades and Northern Rockies. They prey on everything from moose to mice, and often rely heavily on scavenging for food during winter.
"The young female wolverine we collared weighed about 19 pounds, and was in excellent health and condition. She hasn't had kits yet, and is probably just a year old," said Aubry. "It's likely that her parents and possibly siblings are in the same general area, so chances are good that we will collar additional individuals in the traps we've set."
Rohrer and Fitkin will continue to monitor three wolverine traps placed before snowfall in locations where wolverines had previously been detected. The log-cabin-style box traps have been set since mid-January, and are checked every day. They are baited with carrion and provide captured animals with a secure and comfortable space until they are released.
A key reason for conducting this research is the need to understand the wolverine's habitat requirements in the Northwest and maintain the habitat without conflicting with other land uses. With help from satellites 600 miles overhead, Aubry hopes to follow wolverines in the north Cascades for at least 2 more years.