Getting to bottom of mysterious elk deaths

A rash of slow deaths had game wardens wondering what was going on in 2004

Editor's note: This is the first of a two-part serial story about the investigation into a rash of elk deaths near Rawlins in 2004. Part 2 will appear here next Sunday.

By Jennifer Frazer

rep8@wyomingnews.com

CHEYENNE - It wasn't until game warden Benge Brown ran out of ammunition putting down elk that he knew Wyoming had a big problem.

It was February 2004, and the Rawlins-based game warden for the Wyoming Game and Fish Department had just returned to the Red Rim, a low red sandstone rise 12 miles west of Rawlins, after spending a few days in Afton dealing with elk getting into haystacks.

Brown had seen just a few elk down with mysterious symptoms before he left for Afton, but he'd thought about them the whole time he was gone, concerned there might be more. One elk down was nothing unusual, but two elk was worrisome.

"When I got back, I drove around looking," he said, "and I didn't have to look very far."

Dying elk were scattered all over the low rocky country of the Red Rim-Daley Wildlife Habitat Management Area, a reserve created primarily not for elk, but for pronghorn antelope.

There were, in fact, several hundred antelope there that February, and they seemed to be fine.

The elk, however, were dying slow, horrible deaths, helplessly stranded on their bellies in snow drifts and caught grotesquely on fences, which they normally could jump with ease.

Once down on their bellies, they were completely unable to rise. Game and Fish personnel found piles of dung nearby that showed some elk had been there for days or weeks, slowly starving to death. Others had tried to scoot around on their bellies to eat grass or to drink snow. Even more strange, their urine stained the snow a fluorescent red-orange.

None of the symptoms matched any malady that the game wardens or vets were familiar with. Before it was over, an estimated 500 would die.

But on this day, Brown did not know this. He only knew the time had come to take serious measures.

"That's when I started making phone calls to supervisors and started raising every alarm I could," he said.

A sudden problem

It was only days earlier, on Feb. 8, that the first report had come from two coyote hunters to Sinclair Game and Fish biologist Greg Hiatt of a crippled cow elk they had seen two days earlier, stumbling on her hind legs. There were blood stains nearby, they said.

The hunters led Hiatt to the cow. As they approached, the herd fled, but the cow was unable to rise.

It is not unusual to find a crippled elk here or there, Hiatt said, as one might dislocate a hip or break a back getting across a fence or stumbling in a draw. So he was not too concerned when, as a blizzard and sunset closed in on him, he made a cursory examination of the elk, determined it was not able to get up and put it down.

But 2004 had not been usual in a number of ways - not least of which were the hundreds of elk that would soon lie dying in the desert west of Rawlins.

The unusual conditions began with one of the hottest summers on record.

But the unusual conditions began with one of the hottest summers on record, which stunted the growth of the grass that elk prefer. Then there was the fact that the elk were on the Red Rim at all. Normally, they wintered on the Atlantic Rim, five miles to the south. There are 25 to 30 elk who call the desert home year-round, 800 elk migrating on to the Red Rim, as happened in 2004, was unusual.

But because that summer had been extremely dry, there wasn't much forage or snow on the Red Rim. Sagebrush stuck out of the snow, and some areas were swept clean by the wind.

And where the elk chose to go was unusual too. Instead of staying high on the rim, Hiatt said in his report for the Game and Fish Department, they moved onto the greasewood flats and meadows along Separation Creek immediately south of the Union Pacific Railroad.

Sightseers took notice. The elk were visible from the wildlife habitat management area's main road, and people drove down to see the elk on several weekends in December 2003 and January 2004.

Many involved in search

As the blizzard approached and Hiatt finished his inspection of the first downed elk and prepared to leave, the two coyote hunters returned from a hunt to the south and reported more bad news. They had seen a second downed elk about 400 yards to the south of the first elk and had seen another four or five elk stumbling around, they said.

"One elk that can't get up is an oddity," Hiatt said, "But having two in the same place, you start thinking something's wrong."

The next day, Hiatt returned to the carcass of the first elk with Brown and game warden Kathy Crofts. The elk had been partially scavenged by coyotes, but they were still able to examine it and could find nothing obvious that would have prevented the elk from walking.

Its muscles did have some pale streaks, they noted, a sign of myopathy, or muscle cell death. There also were also red-orange urine stains nearby, which the coyote hunters had mistaken for blood.

They walked south to the second cow, seemingly paralyzed by the same symptoms as the first. Though still alive, coyotes had torn at the downed elk's rump, and signs in the snow, Hiatt noted in his report, showed the coyotes had spent much of the night within 15 feet of the elk without the it rising or driving them off.

They put this elk down too, and took it for necropsy at the Wyoming State Veterinary Lab.

Veterinarian Walt Cook with the Wyoming State Veterinary Laboratory and veterinary pathologist Todd Cornish with the Wyoming Game and Fish Department examined the elk and couldn't find anything remarkable.

"I'm sorry to say that's not real unusual," Cook said. "There's a lot of time animals die and we can't figure out why."

Lab results showed nothing more unusual than the pale muscles. When tissue samples were placed under a microscope, pathologists saw that muscle cells in the pale areas had died. But it was still unclear whether this was the cause of the animals' condition or the result.

But in the next few days, seven more elk were found down in air and ground searches of the same area.

Lab tests inconclusive

On Valentine's Day, Cornish and Cook dissected some of the elk in the field and found more myopathy, but still no definitive answers. They did have some guesses.

When elk are chased or run hard, they can suffer a condition called capture myopathy. The condition can cause coffee-colored urine and myopathy, Cook said. Perhaps these elk were harassed by tourists or coyotes.

But they also had myopathy in their hearts and diaphragms - muscles that don't usually sustain damage with capture myopathy.

Brown also knew that these elk hadn't run at all. Even elk that are run very hard seldom go down from the exertion, he said, certainly not by the dozen.

By this time, the number of downed elk was escalating as ground and air searches were stepped up. The total jumped to 14, then 34.

On Feb. 20, 2004, Hiatt spotted 20 downed elk from the air, some of which may have been counted before.

But he also spotted some 600 elk on their normal Atlantic Rim wintering ground - just miles away - that showed no signs of illness.

On that same day, a large party of game wardens, veterinarians, pathologists, toxicologists and students searched the northeastern portion of the Red Rim from the ground and found 28 more afflicted elk, both dead and alive, bringing the total to 62.

By this time, coyotes had stopped harassing live downed elk, Brown said. There were so many dead elk, there was no need for them to waste their energy on the living.

Searching for the cause

Officials had already begun to scour the environment for clues to what could be causing the deaths.

Because elk in the Atlantic Rim and elk just across Interstate 80 - both just a few miles from the Red Rim - showed no signs of disease, it seemed unlikely that an infectious agent was the cause. Indeed, lab results so far had turned up no suspicious viruses, parasites or bacteria, and certainly not any of the usual infectious suspects such as chronic wasting disease or brucellosis.

Lander and Green River habitat biologists Chuck Clarke and Kevin Spence, according to Hiatt's report, reviewed vegetation and range reports for the area to check for unusual plants that might be a source of poisonous toxins. Range conservationists from the Rawlins Field Office of the Bureau of Land Management did the same.

They found only one unusual plant called Kochia, but it was an unusual time of year for a poisoning from this plant. There were no other plants that were out of place in this part of the desert.

Suspicion also fell on the newly drilled coal-bed methane wells in the area and a single artesian well found in the middle of the elk die-off. Sometimes artesian wells can bloom with poisonous algae, Hiatt said. But tests of water samples from these sources showed nothing out of the ordinary.

They also considered the possibility that a train had spilled something toxic along the railway, but no such spills were found.

On that day, Feb. 20, Brown and Dr. Merl Raisbeck, a toxicologist at the University of Wyoming, rode together to look for potential sources of toxin.

They racked their brains for new ideas.

Raisbeck had pointed out, Brown said, that there were close to a million known toxins, and they almost all had to be tested for individually.

"There was a fair chance we'd never find out what poisoned these elk if it was out of the ordinary," Brown said. "They were spread out on close to 50 square miles of ground. So it was a large area. And it just seemed like you got to thinking, 'What could it be?'"

As it would turn out, the answer was right underneath their feet, and after a little thought, Brown was soon to suggest it.

(To be continued ...)

Posted on Sunday, November 26, 2006