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A campaign to prevent an ecological catastrophe by exterminating foxes introduced in Tasmania has become clouded in a mist of slander, intrigue and conspiracy theories.
The Government of the island state is convinced that a population of European red foxes has been introduced to the island, either by accident on container ships or deliberately in an act of malicious eco-terrorism.
Unlike mainland Australia, Tasmania has until now remained fox-free and boasts the country's healthiest populations of small marsupials such as bettongs, bandicoots and pademelons - exactly the kind of prey favoured by the rapacious Vulpes vulpes.
But the alleged foxes have proved maddeningly elusive and the Apple Isle is divided as to whether they exist at all.
The debate over whether foxes are fact or fiction arouses strong emotions in the gentle valleys, sandstone market towns and cosy pubs which give much of Tasmania a distinctly English feel.
Skeptics are convinced that the few carcasses that have been found were smuggled in from neighbouring Victoria, a ferry ride away, as part of an elaborate hoax.
Doubters believe that some shooters are so resentful of Tasmania's strict hunting controls that they have launched a murky "bio-sabotage" plot to publicly humiliate the national parks and wildlife service.
There is even suspicion that some evidence, such as fox scat, may have been planted by rangers in order to justify the generous A$56 million ($65 million) which the state and federal governments will spend on fox eradication over the next decade.
"Their evidence is so flimsy," said David Obendorf, a veterinary pathologist who has reviewed the wildlife department's findings.
"There's so much potential for fabrication, concoction and hoaxing. I was able to logically demolish, in every instance, the claim that these animals are established in the wild."
Obendorf has offered a A$1000 reward for anyone who can produce a dead fox with sufficient evidence to prove that it died, or was killed, in Tasmania.
The mood of doubt among Tasmanians is fuelled by the lingering debate over whether the island's dank rainforests may still harbour a remnant population of Tasmanian tigers or thylacines.
Each year there are claimed sightings of the striped marsupial wolf, despite science having declared the species officially extinct.
Only four fox carcasses have been found since 2001, with claims that at least three were planted.
The fox eradication taskforce believes that there are around 400 wild foxes roaming Tasmania but its officers concede they have yet to find a den, a litter of cubs or a pregnant vixen.
Last year they laid 10,000 kangaroo meat baits laced with poison. This year the number will increase to 50,000.
Not a single poisoned fox has been discovered, although the head of the taskforce, Alan Johnston, said that is not surprising.
"They go into their den or a hollow log to die. We don't expect to find oodles of dead foxes lying around all over the place."
The taskforce believes that the fox population is small but growing rapidly and that unless exterminated, foxes will number in their hundreds of thousands within decades.
If that happens, they would drive to extinction many of Tasmania's rare marsupials and wreak havoc on sheep farms, attacking new-born lambs.
"If we get to the point where people are seeing foxes all the time, then the game will be up," said Johnston. "We have to act before we get to that stage."