Pubdate: Sun, 08 Sep 2013
Source: Sacramento Bee (CA)
Copyright: 2013 The Sacramento Bee
Contact: http://mapinc.org/url/0n4cG7L1
Website: http://www.sacbee.com/
Details: http://www.mapinc.org/media/376
Author: Edward Ortiz

POT GROW SITES' POISONS CITED IN FISHERS' SURVIVAL STRUGGLES

It was midday on Aug. 30, and the sun blazed over two undercover law 
enforcement officers as they entered an illegal pot farm. Like so 
many in the Central Valley, this farm was hidden in plain sight, a 
stone's throw from Interstate 5, near Galt.

The sweep revealed no humans, but enough d-CON strewn about to kill 
several rats.

It was a classic example of the environmental degradation caused by 
widespread, illegal pot farming on public land. Rat poison threatens 
whatever species shares habitat with such grow sites, and no animal 
is more imperiled than the fisher, a cat-sized member of the weasel 
family who lives in the Sierra Nevada and its foothills.

A recent study has established a link between rodenticide use on 
illegal pot farms and the failure of the fisher population to expand 
beyond a meager 300 animals in the Sierra Nevada.

The study, a joint effort among scientists at UC Davis, UC Berkeley 
and two other entities, used transmitters to track 46 adult female 
fishers in the Sierra National Forest. Researchers also made an 
inventory of illegal pot farms in the same area. Wherever a fisher's 
territory overlapped with an illegal pot farm, it turned out, the 
species failed to expand its range - an indicator that its population 
wasn't growing.

In the Sierra, fishers live at elevations between 2,500 and 7,000 
feet. The rugged terrain of the fisher's habitat is also an ideal 
place to grow marijuana undetected.

"This is where you have a constant water source and where you can 
avoid detection by law enforcement," said Mourad Gabriel, one of the 
authors of the research and co-founder of the Integral Ecology Research Center.

"You have a band of cultivation there and that's where the fisher is 
holding on. They're not expanding ... and we suspect it's the use of 
toxicants causing that."

The fisher was once found throughout the state and in the Northwest. 
Today it is reduced to living in isolated pockets. Besides the group 
in the Sierra, additional populations live near Lake Shasta and in 
Humboldt County.

The fisher's habitat has shrunk consistently over the past 100 years. 
The species almost went extinct in the 1940s because of extensive fur 
trapping. In the 21st century the state's fisher populations have 
come under pressure from a new development: the increase and 
intensity of forest fires.

Fishers are now found in such low numbers that the California 
Department of Fish and Wildlife is considering listing the animal as 
endangered.

Released in May, the UC Davis study found that 85 percent of the dead 
fishers it collected had anti-coagulant rodenticide in their livers, 
Gabriel said.

Growers, mostly migrants from Mexico, spread rodenticide to keep 
animals away from marijuana plants and to stop rats from chewing on 
the black plastic tubing used for crop irrigation. In many cases, the 
growers dam creeks and streams and then mix pesticides and herbicides 
in the pooled water for eventual irrigation.

At the empty grow site in Galt, which law enforcement had raided in 
June, water lines had already been relaid when agents returned two 
months later. Growers had begun to spread rodenticide, with opened 
boxes of d-CON rat poison sitting a few steps from a creek.

Many of the chemicals used in illegal pot grow sites are banned in 
the United States, and are brought in from Mexico. These include 
Carbofuran - a rodenticide so powerful that a quarter teaspoon can 
kill a human.

For the fisher, the use of rodenticide is a major concern since it is 
keen on feeding on carrion - including rodents. In some cases, the 
fisher eats bait meant for the killing of rats.

That much became clear at an illegal-cultivation-site raid a month 
ago in the Six Rivers National Forest, where 7,500 marijuana plants 
and 14 pounds of rodenticide were found. It was the first direct 
evidence of a fisher death on a grow site.

At that site, a dead fisher was found under a series of hot dogs 
hanging from treble hooks. The hot dogs had been laced with so much 
rodenticide that the dead fisher was found with a piece of hot dog 
lodged in its throat. "That means the fisher died acutely ... as he 
was eating it," Gabriel said.

"We've been looking for that needle in the haystack - a direct 
poisoning attributable to a grow site," he said. "And now we have one."

Many more fishers die from rodenticide exposure that can be 
quantified, said Gabriel.

His study contends that exposure to the chemicals also leads to 
secondary reasons for death, because rodenticide exposure predisposes 
animals to slower reflexes, a reduced ability to heal from injuries, 
and neurological impairment.

And with female fishers, it is likely that rodenticide is passed on 
to offspring.

Presently, an effort is under way to clean illegal grow sites and 
return them to as close to their original condition as possible. That 
job falls to individuals such as Shane Krogan, executive director and 
founder of the nonprofit High Sierra Volunteer Trail Crew.

The nonprofit has been reclaiming sites in partnership with the U.S. 
Forestry Service and the state's department of Fish And Wildlife. 
Krogen and his team of volunteers have reclaimed more than 400 sites 
since 2004. He said it does not take long to find evidence of 
environmental degradation upon entering a grow site

"We'd go into these sites and we wouldn't find lizards. We wouldn't 
find mice," he said.

Krogen said establishing rodenticide use was sometimes as easy as 
counting the toothbrushes found on the site.

"Generally, wherever a grower sleeps is where they will put a lot of 
rodenticide to keep mice and rats from coming up to them in the 
middle of the night."
- ---
MAP posted-by: Jay Bergstrom