For the past three years, the state of Colorado has required that the brains of all domestic elk that die on elk ranches be tested for chronic wasting disease, a deadly brain malady related to mad cow disease (HCN, 12/18/00: Cure or curse?). In late September, the state's vigilance paid off.

Officials discovered the disease in seven elk herds around the state, the worst outbreak in U.S. history. All but one of the infected elk were quickly traced back to the Elk Echo Ranch, a 2,000-acre breeding and boarding facility near the community of Stoneham in northeastern Colorado.

By the time the state discovered the infections, the Elk Echo had shipped over 400 elk to facilities around Colorado and to 15 other states. The outbreak could have an enormous impact on the region's elk ranching industry - as well as on wild herds of deer and elk - and state officials in Colorado and elsewhere are pulling out all the stops to contain it.

As of mid-October, 1,131 domestic elk and a small herd of captive white-tailed deer were scheduled for destruction in Colorado. The state has purchased a special "air curtain" incinerator, which is supposed to raise temperatures high enough to neutralize the infectious disease agent, to dispose of the carcasses. State officials will transport about 150 live elk to Fort Collins for research on the disease, but the consequences of escape are considered so serious that the animals will be marked with orange paint and accompanied by a truck carrying a marksman with a rifle. New Mexico and Idaho also plan to depopulate herds that include animals traced to the Elk Echo Ranch.

"We're going to wipe out the herds where we've found it, all of them," says Jim Rubing, the chairman of the Captive Wildlife and Alternative Livestock Board at the Colorado Department of Agriculture. "Until we start depopulating, we're not going to know the extent of the problem."

Questions at ground zero

Craig McConnell, the owner of the Elk Echo Ranch, told his customers that his herd had been free of chronic wasting disease for more than three years. But Wayne Cunningham, the Colorado state veterinarian, says McConnell's claim to a clean bill of health is suspect.

An elk brain sample submitted by the Elk Echo two years ago was infected with the disease, says Cunningham, but lab technicians forgot to write down the number on the animal's ear tag. McConnell denied that the sample came from his ranch.

"We did the DNA work, and I'm comfortable that it was from the Elk Echo," says Cunningham.

The Elk Echo has reported 12 elk lost to lightning strikes over the past decade, which Cunningham says is "certainly questionable," as are the reports of two animals lost to pneumonia. Captive elk and deer that die of chronic wasting disease often expire from aspiration pneumonia.

There's no hard evidence of wrongdoing, though, and the state will not attempt to revoke McConnell's ranch license. "I'm not saying McConnell's done everything right, but I wouldn't say he's been trying to elude us, either," says Cunningham.

McConnell stands by his claims. But his entire elk herd - 700 head - is scheduled for destruction, and he says he's getting out of the elk ranching business. "I was the leader of the industry in Colorado," he says, "and now I'm done."

The U.S. Department of Agriculture wants to make sure that ranchers have a reason to comply with the depopulation orders. Spurred by the Colorado outbreak, the agency has declared the chronic wasting disease situation an emergency, freeing up $2.6 million in federal funds to compensate ranchers whose animals will have to be destroyed. Though federal officials and the state departments of agriculture will independently assess the animals' value before agreeing on a final figure, ranchers could ultimately receive a maximum of $4,000 a head.

A precedent for the Colorado situation has been unfolding in the Canadian province of Saskatchewan. Over the past year, 6,500 domestic elk have been slaughtered in an attempt to halt the spread of chronic wasting disease on elk ranches there. George Luterbach of the Canadian Food Inspection Agency says elk ranchers have received fair market value, up to $4,000 Canadian per head, for destroyed animals.

In western Saskatchewan, two wild mule deer killed outside the fences of an infected elk ranch have tested positive for chronic wasting disease, and it is believed that the disease was transmitted from the domestic elk. "These are early findings," Luterbach says, "but we have never seen the disease in the wild in Saskatchewan before."

Wild herds threatened?

For three decades, chronic wasting disease has been known to exist at low levels in the wild in northeastern Colorado and southern Wyoming. Mike Miller, a longtime chronic wasting disease researcher for the Colorado Division of Wildlife, says this well-defined "endemic area" has expanded very slowly, if at all, during the past 10 years.

The outbreak of chronic wasting disease on the state's game ranches marks the first time the disease has been found in Colorado outside the endemic area - a development that could threaten the enormous herds of wild elk and deer in southern and western Colorado.

That's why staff from the Colorado Division of Wildlife have been swarming over the Trophy Mountain Ranch north of Walden and the Anta Grande Ranch in Del Norte. Both ranches purchased elk from the Elk Echo Ranch, and both are now under quarantine.

At the Trophy Mountain Ranch, state wildlife staff have already killed 83 wild mule deer believed to have mingled with infected or exposed domestic elk, says agency spokesman Todd Malmsbury. Near the Anta Grande Ranch, wildlife officials have killed 10 wild deer and 10 wild elk. All the wild game animals killed will be tested for the disease.

Miller, the chronic wasting disease researcher, remains positive about the health of Colorado's wild ungulates. "To the best of our knowledge, it hasn't spilled out of any of these game farms yet, and we'll do everything in our power to see that it doesn't," he says. "The good news is that we've caught it early, and we may be able to contain it."

 

Hal Herring writes from Corvallis, Montana.

 

YOU CAN CONTACT ...

  • Todd Malmsbury, Colorado Division of Wildlife, 303/297-1192;
  • Linh Truong, Colorado Department of Agriculture, 303/239-4190.

Copyright © 2001 HCN and Hal Herring