Friday, March 02, 2007

Elusive Wyo. lynx leaves tracks in snow, but not much else

Biologists seek clues to habits of rarely seen cat near Continental Divide.
By Cory Hatch
Date: February 28, 2007

In the parking lot of the Blackrock Ranger Station, photographer Andrew Weller grins and pulls a plastic bottle of bobcat urine from the back of his pickup truck.

With any luck, a square of carpet drenched in the stuff will catch the attention of a Canada lynx, which will step through an infrared beam, triggering a remote camera up on Togwotee Pass.

Weller and I are tagging along with a crew from Endeavor Wildlife Research to look for lynx tracks about a mile west of Togwotee Mountain Lodge. Earlier that day, one of the company’s co-founders, Jenny Burgharat, spotted some fresh tracks about 20 feet from the road. With skis and snowshoes, six of us will follow the tracks through dense lodgepole pine and Douglas fir, wherever they lead.

Canada Lynx, it turns out, are curious cats. Foreign smells, sights, and sounds can elicit brash and even ridiculous behavior. According to Weller, wildlife photographers and biologists will sometimes hang old compact discs from tree limbs, where a lynx will bat at the flashing plastic-encased metal, just as a domestic kitten would assault a piece of string.

Yet, despite their impish streak, lynx remain one of the most elusive creatures in the forest. Of the four Endeavor Wildlife Research biologists and a number of technicians, not one has seen an animal in three years. Just finding tracks is an accomplishment; a single hair is treasure, and scat laden with precious DNA is 24-carat gold.

The tracks we’re following meanders back and forth, sometimes taking a plunge into some impenetrable undergrowth, where they eludes us for a moment or two before they’re spotted 10 yards away and the search continues. Up front, I fan out with Endeavor field technicians Mary Greenblatt and Preston Taylor. When one of us loses the trail, another picks it up a short time later.

In addition to our lynx tracks, the freshly fallen snow is crosshatched with the tracks of numerous snowshoe hares, the lynx’s favorite prey. In Canada, scientists think the lynx population follows closely behind the population cycles of snowshoe hares. Even when hares are abundant, lynx are successful hunters only about 10 percent of the time.

“They are a specialist predator,” says Burgharat. “They definitely are quick-burst animals; the chases aren’t very long, I think the bunnies get away a lot of the time.”

On Togwotee Pass, pushing the southern extreme of lynx natural range, Burgharat guesses that lynx must rely on a more diverse prey base, including red squirrels and grouse. But our lynx is not hunting. If he were stalking hares, the track would lead us in countless loops and figure 8s. Instead we meander due west toward a deep ravine where the track continues unwavering through deep snow to a creek at the bottom.

Though lynx in Wyoming weigh only between 11 and 25 pounds, their feet can be as large as a 130-pound mountain lion’s. The extra footwear keeps the lynx essentially floating across the snow. The lynx also has exceptionally long legs, especially its hind ones.

“It looks like a huge rabbit’s foot,” said Burgharat. “It allows them to turn quick and move fast.”

Individual lynx footprints fall in almost a straight line. Greenblatt digs out one track to show me the shape of the compressed snow. Where a coyote might have a posthole-looking track with a narrower snow compression, a lynx track is fairly shallow and the compressed snow underneath looks more like a thick pancake.

Greenblatt and Taylor stop periodically, brushing the snow from a track or two, searching for scat or hair. The scat, especially, can yield a ton of information. Usually the first sample is sent to a laboratory, where technicians analyze DNA in hopes of identifying a particular animal. If there’s any scat left over, Greenblatt and Taylor will dry the sample and then dissect it under a microscope, gathering information about the lynx’s diet from the types of hair found in its feces.

In addition to scat hunting, Greenblatt uses a CyberTracker, a device that combines a Global Positioning System with an interactive digital data file. Once the track’s position gets updated in the CyberTracker, the device beams the data into a regular Palm Pilot-like device.

“It basically allows us to collect a lot more data in a lot less time and basically stay on the track,” says Burgharat.

Scientists in Burgharat’s company are working to document lynx as far south as the Wyoming Range and even part of the Wind River Range.

Despite the extensive local habitat of Canada lynx, the U.S. Fish and Wildlife Service decided not to include the Greater Yellowstone Area when it designated critical habitat for the threatened species in November. Local habitat didn’t fit the agency’s criteria, it said.

Fish and Wildlife designated roughly 1,841 square miles of critical lynx habitat in Voyageurs National Park, Minn.; Glacier National Park, Mont.; and North Cascades National Park, Wash. According to Fish and Wildlife, National Park Service management plans “lack specific guidance on lynx conservation.”

The designation does not include land in other Western states, including Colorado and Wyoming. Fish and Wildlife has reintroduced a number of lynx into Colorado in recent years, and conservation groups there have expressed confusion over the agency’s reluctance to protect land there.

In Wyoming, most of the Greater Yellowstone region has a history of lynx sightings, including the 1960s and 1970s, when the animals were considered relatively abundant.

According to Endeavor Wildlife Research, the area contains habitat for the majority of the Fish and Wildlife criteria, including adequate denning sites, soft and powdery snow, young forests as well as older forests with multiple stories, and secondary prey species like red squirrel and grouse.

The only question mark is whether adequate numbers of snowshoe hares, the lynx’s primary food source, exist in Greater Yellowstone. The animals are abundant, at least on Togwotee Pass.

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