Tasmanian devil may be on way to extinction

Published on 28/01/2005 00:19

THE Tasmanian devil, an animal made famous by the Warner Bros’ cartoon character, is facing extinction from a mystery disease.

About half of the wild population of 150,000 in Tasmania has been wiped out in the past eight years by an incurable facial cancer, which might have been caused by them fighting over food.

The island is the only remaining natural habitat of the bad-tempered, smelly, black, fox-sized marsupial with a bloodcurdling growl and powerful jaws that crunch through the bones of much larger animals. It bears little resemblance to the Warner Bros’ version.

Alistair Cotter, the leader of a state government task force searching for the disease’s cause, said yesterday that the cancer, combined with the devils’ competition for food from a substantial population of foxes, could eventually drive the world’s largest marsupial carnivore to extinction.

"That’s a pretty awful prospect," Mr Cotter said. "At this stage, we’re not looking at the prospect [of extinction]. However, we are very concerned about the situation."

Several foxes are believed to have been introduced to Tasmania from the Australian mainland four years ago and the state government has been attempting to eradicate them and their offspring ever since.

"Our belief is that devils may have prevented foxes establishing in Tasmania in the past by taking any young that have been produced," said Mr Cotter, a government nature conservation manager.

"If foxes do establish here and the devil numbers are at a low ebb, that could significantly alter the nature of Tasmanian biodiversity."

Some believe the disease has been caused by contamination of the devils’ food supply or their environment.

But researchers suspect a more likely cause is that the disease has been passed from devil to devil as they bite and scratch each other while squabbling over animal carcases.

Devils eat carrion such as snakes, birds, rodents, lizards, and wallabies.

The massive facial tumours reduce the animal’s ability to feed and kill in about six months. Tests are about to take place to examine whether natural or man-made toxins could cause the cancer.

"Chemicals are a possible cause, among a range of other causes," said Alistair Scott, the project manager of the Tasmanian state government’s devil disease taskforce.

"But there are a number of other possibilities: it could be an exotic disease, it could be a disease which has come from another species, it could be something else we haven’t figured out.

"Over the past 12 months, we have made good progress in determining the genetic structure of the disease, but what we don’t have at the moment is a diagnostic test and we have no clues as yet as to what might be causing it.

"It is a very rare, transmissible cancer and there’s only one known disease like that in the animal world, which is a canine venereal disease where you have physical transmission of cells.

"It’s very disturbing and obviously of great concern to us. We think about half the wild population, about 75,000 animals, have been lost although it’s difficult to estimate because they are a wild, nocturnal animal."

Mr Cotter said researchers expected to understand what causes the cancer within a year. "Whether that will lead to a cure, we don’t know at this point," he said.

Devils can give birth to 40 tiny offspring at a time. But a mother can nurse only four in her pouch at once, and the remainder die.

Once found all over Australia, the devil is believed to have been wiped out on the mainland by wild dogs centuries before white settlement in the early 19th century.

The devil’s cousin, the large dog-sized Tasmanian tiger, is thought to be extinct. The last known member of that species died in a Tasmanian zoo in 1933, although unconfirmed sightings have frequently been reported since then.

The devils became internationally famous through the creation of the ferocious Tasmanian Devil character in Warner Bros’ Looney Tunes cartoons.