A Tasmanian Devil

Oct. 31 — Wildlife experts battling a mystery disease that has killed half the world's population of Tasmanian devils said Thursday that the illness could prove as hard to eliminate as HIV or SARS.

Devil Facial Tumor Disease (DFTD) has nearly eliminated the marsupial predators from the eastern half of Tasmania and there are signs it is spreading to populations in the west, said Nick Mooney, a wildlife management officer with the island state's conservation department.

The disease manifests itself as small lesions and lumps around devils' mouths that grow into cancerous tumors on the face and eventually spread throughout the entire body.

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Death occurs within three to five months, usually from starvation as weakened animals lose the ability to compete for food.

Mooney estimated that from a high of about 150,000 in the mid-1990s, the population of Tasmanian devils has been slashed to 75,000 by DFTD, an illness about which pathologists know little.

Devils — muscular, short-legged animals the size of a small dog but with jaws powerful enough to crush bones — live wild only in Tasmania. There are only about 120 of the animals in captivity, all but one of them in Australia.

Experts from around Australia and beyond gathered in the Tasmanian city of Launceston earlier this month to develop a strategy for finding the causes of DFTD and battling the disease.

"Our big problem is that we don't even know for sure if this is an infectious disease or not," Mooney told AFP. "A retrovirus seems the most obvious suspect, but not all the cancers are caused by these."

"The thing which seems clear is that there is a suppression of the animals' immune system for dealing with cancer, but the pathologists say we might be years away from finding the answer," he said.

Androo Kelly, who cares for and breeds devils at his Trowunna Wildlife Park in Mole Creek, said there is evidence DFTD may have always been around and that environmental factors may be responsible for the extent of the current epidemic.

"The devils and other animals of the same marsupial family like spotted tail quolls are prone to carcinomas, it's a natural, debilitating disease. Cancers are a part of the devil," he said.

"What we may be seeing now is a nasty manifestation of a cancer which is environmentally induced, possibly due to overpopulation or stress from population density," he said.

The disease has been most prevalent among older males and appears to be spread in part when devils "scrap," or bite each other around the mouth and face during group feeding, Kelly said.

Kelly and Mooney both said it is unlikely DFTD will wipe out the iconic Australian marsupial.

"There have been no clear examples of infectious diseases wiping out whole populations of animals because as the animals become rarer, the rate of transmission falls and the population recovers," Mooney said.

But Kelly is taking no chances, building up an "insurance population" of devils through his breeding program, which already contains 55 animals.

"I don't think they are facing extermination in the wild, but it's prudent to have the insurance population," he said.