My contact at WY G&F called this morning to tell me they solved the mystery concerning the deaths of nearly 300 elk near Rawlins.



The culprit is the lichen "parmelia," which is thought to produce a toxic acid that breaks down muscle tissue. BUT...there is still a question as to why this is seemingly the first incident of its type if elk might have eaten these plants before. -TONY

Thanks for posting this. I'd seen a news report this past weekend that they were looking into this possibility. I'll be interested in what changed that made the lichen so toxic, so suddenly.

MSNBC.com is running this report on it:

Quote:

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Deaths of 300 elk blamed on plant acid
Lichen species appears to break down tissue

Updated: 2:42 p.m. ET March 22, 2004A lichen native to the Rockies has been blamed for the deaths of at least 300 elk in southern Wyoming, a mystery that had baffled wildlife scientists and cost the state thousands of dollars, the state said Monday.

Wildlife veterinarians had suspected the lichen after finding it in the stomachs of many of the elk that died in south-central Wyoming.

To confirm their suspicions, three elk were fed the lichen at research facility. One collapsed and was unable to rise Sunday, the Wyoming Game and Fish Department said. A second elk also started stumbling and a third is expected to succumb quickly, officials said. All three will be euthanized.

The ground-dwelling lichen, known as Parmelia molliuscula, produces an acid that may break down muscle tissue, said Walt Cook, a Wyoming Game and Fish Department veterinarian leading the inquiry.

Native elk not affected
Elk native to the area weren�t affected by the acid, but those killed in the die-off apparently had moved in from Colorado and may have lacked microorganisms needed to neutralize the acid, state biologists said. The Colorado line is 50 miles south of the area where the elk died.

�Elk don�t normally winter down on the ... unit where they ate the lichen,� Game and Fish spokesman Tom Reed said.

�Elk are incredibly adaptable, tough animals. They�ll get by on thin rations and they�ll make do somehow. But this year, nearly 300 of them paid the price for that adaptability,� Reed said.

The first sick elk was found on Feb. 6 and scientists quickly ruled out chronic wasting disease, the deer and elk version of mad cow disease. They also eliminated most viruses and bacteria, malnutrition, exposure to heavy metals such as arsenic, and poisoning from a leaky gas well or pipeline.

The search for the cause became expensive. For a time, researchers used a helicopter to search for afflicted elk, but the flights cost $900 an hour. Wildlife experts also drove into the rough country near the Continental Divide and slogged through melting snow and mud to collect plant specimens and elk droppings.

Why so acidic?
Scientists still want to know more about the lichen and why it contained high amounts of the acid this year.

�There are a lot of factors we�ll need to look at,� Reed said. �Do elk eat this lichen in normal years? If so, why hasn�t this happened before? Does a long history of drought weigh in somehow? If so, what are our management options in the future?�

The die-off killed up to 5 percent of the Sierra Madre herd�s breeding females, and that will affect hunting quotas this fall and could trigger wildlife policy changes, Reed said.

Other steps, such as improving range conditions to provide healthier forage, will also be considered as researchers learn more and try to prevent future die-offs.

� 2004 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

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And here's the press release from WY G&F which came to me via email a bit ago. -TONY



March 22, 2004

Contact: XXXXXX (###) ###-####

For Immediate Release



RED RIM ELK MYSTERY SOLVED



RAWLINS -- A little plant that is part fungus and part alga is responsible for the deaths of nearly 300 elk near here. The plant is a lichen known as parmelia that is abundant in desert soils around the state.



�We had lichen on the list of toxic plants that our veterinarians were investigating,� said Tom Reed, spokesperson for the Wyoming Game and Fish Department. �We were faintly optimistic that this may have been the cause, but didn�t want to get our hopes up.�



This past weekend, tests revealed that the lichen was indeed the cause of the strange affliction that had taken down 295 elk in a month�s time. On Feb. 8, two cow elk were discovered in the desert about 15 miles southwest of Rawlins that could not rise and run when approached by agency personnel. As field crews searched the area in subsequent days, the number of elk afflicted slowly increased to nearly 300, scattered over a 50-square-mile area of high desert in and around the department�s Daley Ranch Wildlife Habitat Area. All exhibited the same symptoms: inability to rise from the ground, while remaining alert and vocal. Elk that were not found and euthanized by agency personnel died a slow, stressful death from starvation or dehydration.



Scientists found parmelia in the stomachs of afflicted elk, starting an exhaustive chain of investigation. That effort was borne out this weekend, when captive elk that had been on a diet of parmelia went down with the same symptoms, said Dr. Terry Kreeger, veterinary supervisor with the department.



Parmelia produces an acid that may break down muscle tissue, causing the elk to lose strength, said Dr. Walt Cook, G&F veterinarian who has been working on this incident non-stop since it was discovered more than a month ago. Cook and colleagues at the Wyoming State Veterinary Laboratory were instrumental in narrowing down the laundry list of possible causes, but more work will need to be done in coming weeks.



�We are going to need to do further necropsy work to explore the exact physiology behind this,� said Cook.

Additionally, officials are going to try to learn more about the lichen itself and why, or if, it accumulated inordinately high amounts of acid this year.



�There are a lot of factors we�ll need to look at,� said Reed. �Do elk eat this lichen in normal years? If so, why hasn�t this happened before? Does a long history of drought weigh in somehow? If so, what are our management options in the future? These are all questions we are going to try to answer in the coming months.



�But we�ve answered the biggest and most important question: What the heck is killing these elk?� said Reed. �It�s a huge relief for everyone involved. A lot of people worked their tails off on this mystery. But we have some of the best minds in wildlife science right here in Wyoming and they came up with results.�



Healthy elk that were wintering on the Daley Ranch southwest of here are now following the receding snowline back toward the Sierra Madre Mountains, and three cows in that herd are wearing radio collars so biologists can learn a little more about this elk population.



�Elk don�t normally winter down on the Daley unit where they ate the lichen,� said Reed. �But for whatever reason, this year they moved in there. Elk are incredibly adaptable, tough animals. They�ll get by on thin rations and they�ll make do somehow. But this year, nearly 300 of them paid the price for that adaptability.�



No other animals including horses, cattle, antelope, deer or scavengers in the area were afflicted.< !--color-->