Stalking the elusive fisher
A combination of low- and high-tech equipment is helping wildlife managers locate an elusive species scarcely seen since the 1960s in the forests west of Klamath Falls.
The high-tech equipment includes a trail camera with day and night photo capabilities. The low-tech resembles a tubular back scratcher with a treat inside.
Steve Hayner, a wildlife biologist for the Bureau of Land Management, said the contraption — a 6-inch-diameter pipe adorned with small brushes and a piece of meat dangling inside — should be enough to entice a fisher, a cat-sized member of the weasel family, into the camera’s sights.
Evidence of bears, martens and small mammals, such as golden-mantled ground squirrels and Northern flying squirrels, has been captured in the tube, aptly dubbed a “hair snare,” as well.
“When they reach up to get the chicken, they actually rub some fur off onto the gun brushes,” Hayner said.
When Hayner checked the station Thursday, the camera had been triggered 13 times.
The two chicken legs he placed in it the week before were gone, and tufts of brown hair were lodged in the brushes.
“By the length of the hair and the fact that the brush was actually bent, I’m thinking it wasn’t a squirrel. It was something bigger,” Hayner said.
Sometimes Hayner’s stations, located across a checkerboard of western Klamath County BLM land, collect only hair or only images; sometimes they collect both. Even when photographic evidence shows a fisher visited a snare, Hayner still sends the fur into the Rocky Mountain Research Station in Missoula, Mont., for genetic testing.
Laura Finley, a wildlife biologist for the Yreka Fish and Wildlife office, noted that although digital technology is effective for confirming a fisher’s presence, it doesn’t tell researchers everything they need to know.
“You don’t know if you’re taking a photo of one animal 10 times or 10 animals one time,” Finley said.
She explained that fur trapping and predator control methods, such as poison used by forest-related industries, nearly wiped out Northwest fisher populations in the early- to mid-20th century.
Fishers — small mammals typically about 3 feet long — are noted for their ability to run down trees head first. They also are one of the only species specially adapted to prey on porcupine.
“They’re quick; they’re fast; they’re strong, and they have a very aggressive temperament,” Finley said.
According to Hayner, fisher populations faltered and porcupine populations boomed in the aftermath of eradication efforts. In 1961, resource managers attempted to stabilize fisher populations by introducing East Coast fishers in Southern Oregon and at Crater Lake National Park.
Native Northern California fishers are substantially smaller than East Coast fishers, according to Finley.
Since then, fisher populations have slowly re-established themselves in Southern Oregon and Northern California, but they are not out of jeopardy yet. In addition to threats from wildfire and other habitat destruction, rat poisons placed at illegal marijuana grow sites are affecting fisher health and are known to be fatal.
More than 50 years later, current figures for Northwest fisher populations are still uncertain.
The U.S. Fish and Wildlife Service is determining whether to designate the species as “threatened” and give it Endangered Species Act protections.
Erin Williams, area office manager for the Yreka Fish and Wildlife office, said officials are hoping the ESA public comment period that closed Feb. 5 will help refine population data: current estimates span between 1,000 and 5,000 individuals in Southern Oregon and Northern California.
A separate population in the southern Sierra Nevadas has about 200 to 350 individuals, Williams added.
Hayner said since he began surveying the Klamath County BLM region, genetic testing has confirmed three individual fishers have visited his snares.
“We are still waiting on some samples. It’s more than likely that we have more than three,” Hayner said. “I’d guess we have at least four or five individuals, but we’ll have to wait for the DNA samples to get back.”
Hayner said genetic tests could reveal genes from fishers or a number of other opportunistic species.
“Fisher will eat carrion — dead deer, dead elk, dead whatever. That’s why we use chicken,” Hayner said.
Strangely, fish is not a main staple of a fisher’s diet.
“I’m not saying they don’t eat fish, but it’s not part their mainstay. You seldom find fish in their diet,” Hayner said.
The name fisher may originate from the French word “fichet,” which refers to the pelt of a European polecat, another member of the weasel family, according to Encyclopedia Britannica.
Hayner has only one snare station set up right now. Next month, he plans to survey a 12-square-mile area by staging two snare setups per four square miles. The cameras will be in place for 30 to 45 days, in areas with downed wood and broken-top snags or branches that fisher can use for platforms and resting sites.
The advance of technology since Hayner’s last fisher survey, done between 2001 and 2006 under the umbrella of a lynx survey, has made his job more exact and more gratifying.
“As far as our success in getting pictures with film versus digital, it’s fantastic,” he said.
Hayner explained that before the advent of digital cameras, biologists hoping to capture images of animals at survey sites had to set up a 35 mm film camera with a cable trigger attached to the snare.
“You had to send the film in to be developed and you had to wait. If there was enough wind or snow blowing or falling out of trees, it would trigger the camera, and sometimes we’d get a snowstorm when we developed the film,” Hayner said.
“The meat would be gone, and you get the film back, and there would be 36 pictures of a snow field.”
The other problem, Hayner said, is that squirrels love to chew on things.
“Some of the time they would chew on our cable, so you’d get out there and the meat would be gone. There’d be tracks everywhere and the camera didn’t shoot anything because a squirrel ate the camera cord,” he said with a laugh.
But even with the ease of today’s high-tech technology, Hayner doesn’t always get the results he wants. While reviewing the digital memory card pulled from his camera on Thursday, Hayner realized the only animal the camera captured was an upright, two-legged mammal that worked for the BLM. Hayner will have to keep testing this site for photographic evidence of the ever-elusive fisher.
Contact Lacey Jarrell by email at email@example.com or follow her on Twitter @LMJatHandN.