Sympathy for the Devil

Fro

m inside the hessian sack comes a low growl. Wildlife biologist Nick Mooney reaches in and carefully pulls out a Tasmanian devil, the largest carnivorous marsupial, a halo of stiff whiskers framing bright brown eyes and rich, dark fur; an open mouth revealing sharp teeth. Tasmania is famed as much for its creatures as its landscapes, and chief in this unique menagerie is the devil, reportedly so named by early settlers, who were rattled by its ferocity and the ungodly sounds of its squabbles over food. Few ever get this close to the stocky, dog-like creature, which scavenges by night, cleaning the bush and farmlands of dead and dying animals, then retreating with daylight to dens among the ferns and heath. But the animal settlers once feared is now one of Tasmania’s favorite symbols, adorning souvenir key rings and sports-club logos. Unlike the extinct thylacine, or Tasmanian tiger, devils survived decades of now-banned hunting, and are still considered common. But perhaps not for long. A grotesque disease is striking devils down, just as a new predator readies itself to seize their place at the top of Tasmania’s ecological pecking order.

It’s dawn on a January morning, and the sky is streaked vivid pink as a team from the state’s Department of Primary Industries, Water and Environment heads into state forest bordering the Wilderness World Heritage Area in Tasmania’s rugged Central Highlands. The logging road crosses the Nive River, running silver in the early light, and winds among snow gums covered in creamy blossoms. Plenty of ground cover makes this perfect devil country, home to a daily smorgasbord of wallabies and other treats. That’s why Mooney, scientific officer Billie Lazenby and conservation officer Andry Sculthorpe are here, hoping to catch enough devils to help them unravel the cancer-like disease that’s believed to have halved the devil population and is still spreading.

Precisely how it’s doing that is baffling experts, for the killer, known as devil facial tumor disease (DFTD), is as mysterious as it is disfiguring. Today Mooney’s team are checking their 50 traps - lengths of PVC pipe pierced with air vents and nestled in shady spots - measuring, weighing and attaching microchips to healthy and sick devils as part of a new statewide monitoring program. There’s still no diagnostic test, so the team must check the face and gums of every animal, disinfecting each trap as they empty it. But there’s no missing the disease in its advanced stages, when faces are ravaged by huge, weeping tumors. Before she saw it, says Lazenby, “I couldn’t imagine anything so horrific.” Of the 50 devils the team has found in five days, 14 have shown clear signs of DFTD - perhaps a sign that the disease is only just moving into the area. These animals will almost certainly die within months, some starving to death as tumors block their mouth or throat. Autopsies on other devils have found their internal organs riddled with tumors. The disease, confined so far to the state’s eastern half, is believed to have cut the animals’ population to about 70,000 from a peak of 150,000 in the early 1990s.

The first hints of DFTD surfaced eight years ago, when a photographer contacted Mooney to tell him of terrible tumors he had documented in devils in Tasmania’s northeast. Then, in 1999, one of the world’s few devil experts, zoologist Menna Jones, reported similar tumors among animals she was studying on the east coast. But it wasn’t until late last year that a statewide snapshot survey revealed the full extent of the epidemic. Despite the Tasmanian devil’s iconic status and its key ecological role as a super-efficient scourer of the bush, requests for a program to monitor the species have been refused for more than a decade, says Mooney. “If something isn’t endangered or threatened, no one wants to spend any money on it,” he says. “A lot more fundamental monitoring used to be done - and without it, you get caught with your pants down.” Gordon Grigg, professor of zoology at the University of Queensland and a member of the Commonwealth’s Threatened Species Scientific Committee, has been monitoring kangaroos since 1974. He says long-term monitoring usually happens only if a species is commercially harvested, a pest or attracts the interest of scientists or hobbyists. Grigg’s colleague Tony Pople, a population ecologist, agrees: “Monitoring is a luxury that we can’t afford with limited conservation and management dollars - you’re forced to monitor only when you need to.” When Mooney and a visiting ecologist, Marco Restani of Minnesota’s St. Cloud State University, carried out that first snapshot survey last year, Restani paid for the hire of their trailer. Since then, Tasmanian Labor premier Jim Bacon, promising that the devil will not follow the thylacine into extinction, has committed $A1.8 million. The federal government has provided no funding: Environment Minister David Kemp says that while he would be “open to any approach for assistance,” managing wildlife is a state responsibility. The Commonwealth usually gets involved only once a species is listed as threatened - a move that may not be far off for the devil.

So sparse is information on devils in the wild that scientists at the state-run Animal Health Laboratory in Launceston are trying to figure out just what a healthy devil should look like. Performing an autopsy on a diseased devil, veterinarian Robyn Sharpe painstakingly cuts out pieces of tissue. “We have to take everything because we know so little about devils,” she says. The animals “have been like seagulls,” says her pathologist colleague Richmond Loh, “so common that no one’s really studied them.” Now Loh and others are racing to determine whether the disease is caused by a virus, how it’s transmitted and how it progresses. Until such questions are answered, radical options such as relocating devils onto offshore islands remain too risky. No one knows if DFTD could jump to livestock or people, and it’s so cryptic, Loh says, that pathologists cannot agree on what sort of tumor it is: “The only things we’re certain of are that it’s spreading and that it’s affecting animals in the prime of their lives.”