Wyoming’s Red Desert
The elk died in small groups, big groups and sometimes alone, staggering across this parched high sage and greasewood desert just north of the Colorado border and then crashing awkwardly to the ground, unable to get up. Death took a day or more.
When the bizarre scenario was over, the bodies of as many as 500 elk were scattered across the harsh landscape.
“I have a lot of memories of those months, and none of them are good,” said Wyoming Fish and Game biologist Greg Hiatt. “Blowing snow and sagebrush and as far as you could see, elk that couldn’t get up.”
For weeks, the strange deaths that began in February 2004 baffled scientists. They took blood and tissue samples and ran exhaustive tests – 40 to 60 lab experiments searching for poisons, toxins, viruses and deadly bacteria. They found nothing.
Today, wildlife biologists and the Food and Drug Administration have the answer. The chemical that killed the elk was usinc acid. It was contained in a specific lichen or moss-like plant known as Xanthoparmelia chlorochroa.
It is the same usinc acid once widely used by bodybuilders to burn fat.
The chemical is now banned by the FDA after tests showed it caused liver damage and some human deaths.
“Usinc acid was killing people long before it started killing elk,” said FDA researcher John Roach in Maryland.
The FDA and wildlife biologists continue to study the lichen for other potential harmful effects on humans, wildlife and domestic animals such as cattle that graze along the Red Desert.
The herd of elk in that area along the Colorado-Wyoming border has a range of several hundred square miles, often crossing into Colorado above Craig and Steamboat Springs. Because of the drought that lingered into the winter of 2004, biologists believe the elk moved out of their normal winter range and into an area filled with the lichen, which grows on rocks and on the ground.
And they began to eat.
“It started with a couple of coyote hunters finding an elk that was alive but couldn’t get up,” said Terry Kreeger, supervisor of veterinary services for the Wyoming Department of Fish and Game. “Our people went out and found other elk down. They’d look at you but couldn’t move. You could pat them on the head.”
After the blood and tissue testing failed to turn up clues, a Wyoming biologist thumbing through 1964 literature stumbled upon a story in which lichen was blamed for sickness and death in cattle and sheep.
“We went back out and collected bags and bags of the lichen, maybe 100 pounds or so,” Kreeger said. “We had three captive elk in Jackson Hole, and we brought them to our Laramie lab and began feeding them the lichen.”
Two of those elk ate the lichen and died, one after eight days and one on the 10th day after the feeding began. The third elk refused to eat the lichen. That bull elk is still alive, in a pasture at the Wyoming lab.
“Two ate the lichen and died, one didn’t eat it and was fine. That was the absolute smoking-gun proof that the lichen killed the elk,” Kreeger said.
Wildlife workers eventually found 327 dead elk on the prairie, according to biologist Hiatt. About 80 percent were cow elk.
“But we know we didn’t find all of the bodies,” Hiatt said. “Our best estimate would be that 500 or 600 died.”
Hiatt said the antelope that roam the Red Desert were not affected by the lichen, despite making it a regular part of their diet.
“It’s a well-known high protein winter food for the antelope,” he said.
Roach, the FDA scientist, said a bacteria in the stomachs of antelope likely breaks down the usinc acid. Elk, not accustomed to the lichen, haven’t developed that helpful bacteria.
Today, the herd of elk that was nearly wiped out – biologists believe about 300 animals in the herd of about 800 didn’t eat the lichen and eventually wandered back into their normal range – has returned to its original size. Hunting restrictions were put into place during the 2004 Wyoming season, helping the herd rebound.
And 10 of the elk look a bit different than the others.
“We put radio collars on them,” Hiatt said. “We monitor the herd’s movement that way. Last winter, they didn’t come back to the Red Desert area with the lichen. But this winter, well, if they come back, we’ll just chase them back out.”
Staff writer Rich Tosches writes each Wednesday and Sunday. He can be reached at rtosches@denverpost.com.
