Beelzebub's pup, the diabolical bear, satanic meat-lover. Dogged by a series of spine-chilling names, the Tasmanian devil has long had a woeful public image. But when news came to light that the species was facing extinction from a mysterious facial cancer, scientists from across the state rushed to its defence. Jo Sargent travels to Tasmania to meet the people battling to bring the world's largest marsupial carnivore back from the brink
Pulling out a pocketknife, Geoff King reaches down and deftly slits the roadkilled pademelon from gullet to groin. As the wallaby's innards spill out onto the warm ground, he slips a rope around its throat and hitches it to the back of his track. We head off clown the makeshift track, the carcass bumping along behind us.
We eventually draw to a halt beside the small wooden hut that will be our base for the night. Untying the battered pademelon. King stakes it out on the ground. Scent trail laid and bait in place. we head into the hut to watch and wait.
An alarming discovery
Geoff King's family have been farming in Marrawah, a township on Tasmania's northwestern tip, since the 1880s. In 1997, aware of the impact his 336-hectare cattle farm was having on the local landscape, King made the decision to turn it into a wildlife sanctuary. Now, five nights a fortnight, he brings out here to his 'devil restaurant' for the chance to see Tasmanian devils feeding in the wild, which is dominated by coastal heath, is perfect for devils. And in this isolated bay, we stand a far better chance of seeing one than we would elsewhere in Tasmania, because the once-abundant marsupial is under threat, its numbers cut by two thirds in just ten years.
The first inkling that the species was in trouble came in 1996, when Dutch photographer Christo Baars made an alarming discovery. Working in Mount William National Park on Tasmania's northeastern coast, he photographed devils suffering from gaping facial sores.
Initially, Baars' reports of a mysterious devil disease received a muted response, but it soon became clear that this wasn't an isolated incident--farmers elsewhere in the northeast reported that devil numbers were dropping, and an increasing number of those killed on the roads exhibited similar facial lesions. But it wasn't until marsupial specialist Menna Jones encountered her first infected animal in Freycinet National Park in 2001 that things really began to gain pace.
Devil Facial Tumour Disease (DFTD), as the infection was eventually named. is an overwhelmingly visual disease, causing bloody, festering tumours on an affected animal's face. It initially manifests itself as a series of lesions or small lumps around the mouth that quickly develop into full-blown tumours. These spread to cover large portions of the devil's face and neck, making it increasingly difficult for it to feed. Most infected animals die within three to eight months of the lesions' appearance, primarily due to starvation.
Jones was understandably horrified by what she saw. She contacted local vets, who confirmed that devil numbers had been declining for several years. By 2003, her research had confirmed that numbers were crashing dramatically. A year later, it was apparent that the disease was present in devil populations throughout the eastern half of Tasmania.
Backed by evidence of the disease's spread, Jones secured AU$1.8million (0.7million [pounds sterling]) of government funding to investigate further. At the end of 2003, she helped to establish the Devil Disease Project Team (DDPT), which is broken up into three sectors--pathology, monitoring and management.
The search for answers
Clare Hawkins, the head of the monitoring team, is trapping devils across the state in an attempt to establish the distribution of the disease and its potential impact. "We've got trapping sites that we keep coming back to, to see if numbers are changing and how they relate to the presence of the disease and the timing of its first sighting in the area," she explains. So far, the news isn't good. "What we're finding is that there is no sign of any devils not getting the disease. They age very quickly, reaching adulthood at around two, which is when the disease manifests. Normally, they should live until about six, but it's really rare to find a three year old in an area where the disease is well established."
The good news is that devils breed young, so they are remaining alive long enough to produce the next generation. But it's a delicate balance; numbers are so reduced by the cancer that it doesn't take much to destroy a breeding population. "When I worked in Mount William, there were 250-odd devils living there," says David Pemberton, co-author of Tasmanian Devil: a Unique and Threatened Animal. "Now there are 20, and only three females to produce the next lot, so if you wiped out those three mums, the population would be done for."
While Hawkins and her team are busy in the field, cytogeneticist Anne Maree Pearse has been leading a group of pathologists in Launceston searching for the disease's cause. Earlier this year, they made a major breakthrough: rather than being a virus, as they'd initially assumed, the team discovered that the disease is an infectious cancer, transmitted by allograft--where a tissue from a genetically unrelated donor of the same species grows in the host. "The turnout itself is the infectious agent," Hawkins explains. "It isn't a virus or a bacterium or anything like that--it's actually the turnout cells that are moving from animal to animal."
Pearse made the discovery when comparing tissue samples from infected devils. "Anne Maree was looking at the chromosome structure of the tumour, versus that of the devil," says Hawkins. "She found that the chromosomes in the tumour were massively changed when compared with the composition of the body, much more so than most cancers, and they were identically changed in every devil she looked at."
It was a significant discovery, indicating that the tumours had all originated from a single source, but there is still a great deal of research to be done. "We've only just vaguely identified what it is," says Hawkins. "It could take years to develop a vaccine."
Exactly how the allografting occurs is also still unclear. As Pemberton admits, "we just don't know. But leeches, mosquitoes, that sort of stuff could easily be vectors." The likelihood of DFTD being spread by invertebrates seems slim, but that hasn't stopped the idea catching the public imagination. "We get members of the public writing to us all the time with theories. The idea that wasps are spreading it is very popular," says Hawkins.
Another popular theory is that the cancer could be spread by biting, particularly during mating or feeding. Pemberton is adamant that this is just another symptom of the devil's bad public image. "They don't bite each other a lot," he insists. "In its lifetime, a devil's going to get bitten, for sure, but they don't go out every night and bite every other devil on the face. What they actually do is snort and sniff at them. Nipping and biting are very rare."
Isolating the problem
Until the vector is identified, the only option available for limiting the disease's spread appears to be keeping healthy and diseased devils apart.
Consequently, the pathology team's focus has shifted towards developing a diagnostic test that will allow infected animals to be identified before symptoms appear.
And on the ground, efforts are under way to create viable disease-free devil populations that could be used to repopulate the island once a cure is found. Hawkins explains that an area on the Tasman Peninsula near Port Arthur has been identified as a potential site for an isolated wild devil population. "It's one of the many places in Tasmania with isthmuses and necks and little areas that you can cut off," she says. "There has also been a canal built between the peninsula and the mainland, so they're currently devising a way to deter devils from crossing the bridge and then trying to take every animal that looks diseased off that section of land."
Efforts are also being made to maintain healthy captive populations. "We've set up some 'insurance' populations," says Hawkins. "We might not be able to do anything to stop the disease in the wild, or it might take a long time, so at least we can put some in captivity and keep them well away from wild devils."
Trowunna Wildlife Park in Mole Creek has one of the state's most successful breeding centres. Standing beside the pen at feeding time, owner Androo Kelly watches as the young devils chase each other in circles, tussling over meat and screeching in outrage if one of the others gets a bigger chunk. It's an odd noise, like a chainsaw's roar crossed with a scream.
There are 56 devils housed at Trowunna, and Kelly has bred nine generations, adding and subtracting stock from the gene pool with the help of a carefully maintained studbook. "My population has been breeding for 20 years," he says, "and the animals come from all over Tasmania, so they are definitely genetically viable."
A species under pressure
Cancers that spread by allograft are exceptionally rare--there is only one other known example, Canine Transmissible Venereal Turnout. Ordinarily, cancers can't spread in this way, because the body identifies cancerous cells as foreign bodies and immediately rejects them. In the case of the devils, it seems the turnout is able to spread because, thanks to the species' remarkably low genetic diversity, the animal's body simply accepts the tumour as part of itself.
But where did DFTD come from? Bill Flowers, a wildlife interpreter at Devils@cradle, a newly opened viewing and interpretation centre at Cradle Mountain, feels that humanity--and specifically forestry and agriculture--must shoulder at least part of the blame. "There's a really big push to deny that it's because of our effect on the environment," he says. "But even if habitat destruction isn't the cause, it's making the situation very difficult for an animal that is already under pressure."
Habitat loss is certainly a potential problem. Forty per cent of the state is protected in some way, but according to Pemberton, at least 45 per cent of this land isn't suitable for devils, and the forestry industry is beginning to cut into their habitat.
Others point to the pesticides and other chemicals used by the forestry industry. "We haven't proven that chemicals don't have a role," Hawkins says, "because it could be multi-factorial. For example in the Surrey Hills, we have just found that there is still no disease, despite all of the forestry chemicals used there. As to why this is, it could be that it's a very wet area and the chemicals have dissolved. It'll take a while to be certain about the role of chemicals in DFTD."
Back in Marrawah, we've been waiting in the darkened hut for more than two hours. Despite his earlier assurances, even King seems a little anxious that no devils have appeared, periodically crossing to the window to twitch back the curtain and fiddling with the baby monitor he uses to pick up the sound of approaching animals.
To pass the time, he describes his first devil encounter. Keen to help out family friends whose son had been killed in a hunting accident, King and his family volunteered to look after their farm. "They'd shot 40 or 50 Bennett's wallabies and dumped them about 100 metres from the homestead," he recalls. "My first night down there was my first experience with devils. There was this incredible cacophony coming from the carcasses as devil after devil fought with each other. It was eerie."
As if on cue, the room fills with the sound of bones crunching. Peering through the window, I catch my first glimpse of a truly wild devil--a female, nose-deep in the pademelon's intestines. As it's eating alone, there's none of the chainsaw screaming I'd witnessed at Trowunna, just a silent determination to consume as much as possible before the competition arrives. Her ears twitch as she sniffs the air and she bolts from the clearing several times, only returning to feed when she's certain the coast is clear.
At four years old, our visitor is at least a year older than any devils you'd find in an area affected by DFTD. Watching her stomach bloat as she rips into the pademelon, it's difficult to imagine that such a healthy-looking animal could end up like the disfigured devils found elsewhere. Earlier, Hawkins had struggled to explain the impact of seeing an infected devil up close, but in the presence of a healthy specimen, it's easy to understand how upsetting it must be.
"I'm not completely hardened. Every one we see, it's still shocking," she'd said. "It's just really depressing and it makes you start thinking about the implications for the species."
Pemberton is equally adamant that extinction must not be allowed to occur. "When the Tasmanian tiger became extinct, Tasmania lost its soul," he says. "I worry that if the devil goes, it will lose its heart." Hopefully, with so many people working to ensure its protection, Tasmania's heart will keep beating for a while longer.
Common name: Tasmanian devil
Scientific name: Sarcophilus harrisii
Size: females: 4.5-9kg; males: 5-13kg, length (both sexes): 57-65cm
Lifespan: five or six years; less than three years in diseased areas
Diet: primarily scavengers, but will eat pretty much anything, including small mammals, birds, amphibians, reptiles and shellfish
Reproduction: mate in March, pups are born in April. Females produce upwards of 20 young per litter, each no bigger than a grain of rice. However, females only have four nipples, so the majority die almost immediately
Habitat: can live almost anywhere where food and shelter are present, but usually found in coastal heath and forest
Distribution: once widespread throughout Australia, but wiped out on the mainland by dingo predation around 600 years ago. Now restricted I
to Tasmania (see above) Conservation status: listed as a vulnerable species in 2005
Fascinating fact: the devil's gaping mouth, often mistaken for aggression, is actually a 'displacement yawn' that signifies fear or confusion
Apart from the obvious distress at the thought of losing one of Tasmania's natural icons, scientists are concerned that the devil's decline could disrupt the state's ecosystems. Feeding primarily on carrion, devils act as nature's dustmen. They have played a key role in breaking the cycle of tapeworm infection in Tasmania's sheep populations, keep blowfly numbers down and remove the need to bury dead livestock or rotting roadkill.
"You've got to understand that we're not just losing a species, we're losing the top carnivore in the forest," explains devil expert David Pemberton. "And wherever the disease is, the devils are all one or two years old. They don't run around chomping up carcasses, they're not bone-crunching adults, these are little insect eaters. So the whole ecology out there has changed. And that's really scary, because it's all so interlocked that the whole balance has gone haywire."
When to go
Summer (Jan-Mar) is the most popular time to visit, but in winter (Jun-Aug) it's cheaper, less crowded and still warm.
How to get there
Geographical visited Tasmania with Tailor Made Travel, which offers a ten-night trip including accommodation, international and domestic flights with Qantas, the Geoff King Devil Tour and ten days car hire from 1,519 [pounds sterling]] per person, based on twin share. For a brochure, call 0845 456 8050 or visit www.tailor-made.co.uk. For reservations with Qantas, call 08457 747 767 or visit www.qantas.co.uk.
For further information on Tasmania, visit www.discovertasmania.com.…