PORTLAND, Ore. February 17, 2006. The closest
encounter most wildlife biologists have with wolverines in the
Pacific Northwest is seeing a set of the animal’s tracks
in the snow. But wildlife biologist Keith Aubry recently got the
call he had eagerly anticipated for several weeks.
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
and management needs,” said Rohrer, 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
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
from moose to mice, and often rely heavily on scavenging for food during
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.”
Fitkin will continue to monitor three wolverine traps placed before
snowfall in locations where wolverines had previously been detected.
log-cabin-style box traps have been set since mid-January, and are
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.
pilot study was supported by funds from the USDA Forest Service
and USDI Bureau of Land Management Interagency Special Status/Sensitive
with additional funding and support provided by the Pacific Northwest
Research Station and the WDFW. Continued research on wolverines in
will depend on the availability of future funding.
The Pacific Northwest
Research Station is headquartered in Portland, Ore. It has
10 laboratories located in Alaska, Oregon, and Washington.