Eco-Terrorism Blamed for Tasmania Red Fox Release
Elizabeth M. Tasker
for National Geographic News
|January 30, 2003|
Wildlife officers and local citizens on the Australian island state of
Tasmania are fighting a desperate battle to eradicate a small number of
European red foxes that were illegally released there in 2001.
The fox poses a huge threat to native Australian fauna, having caused the decline and extinction of many native species on mainland Australia. Wildlife managers estimate there may be up to 30 million foxes on the mainland.
The absence of the red fox in Tasmania is the main reason that the island has been something of a Noah's Ark for Australian animals.
But that may be about to change.
"It will be an unmitigated disaster if foxes establish in Tasmania," said Chris Dickman, an associate professor of biology at the University of Sydney. "It's unbelievable that there are people around that hate the Australian environment so much that they'd intentionally introduce foxes there."
Foxes Invade Tasmania
Tasmania is a lush island about the size of Scotland, located off the coast of southeastern Australia. Although settled by Europeans in 1803, much of the island remains a wilderness, and national parks and reserves cover more than a third of its area.
The island state is home to many native animals that occur nowhere else in the world.
"It is the last refuge for many species that used to be widespread, but are now extinct or endangered on the Australian mainland because of foxes, such as the Eastern Quoll and Tasmanian Bettong," said Dickman.
Tasmania has lost only one species of native mammal since European colonization, the Thylacine, also known as the Tasmanian Tiger, a carnivorous marsupial which was hunted to extinction by the mid-1930s. In contrast, mainland Australia has the worst record of mammal extinctions in the world, with 17 species lost in the last 200 years, and many others critically endangered and only just hanging on.
Foxes were first introduced to Australia in the 1850s by wealthy settlers who wanted to hunt them on horseback.
Australia had native predators of its own, but foxes hunt in a different and more cunning way and have a broad and adaptable diet. By the 1930s they had colonized most of the continent.
"The conventional wisdom is that medium-sized mammals and birds are most vulnerable to foxes, and this is certainly the case," said Dickman. "But it is becoming clear that foxes also take small mammals and harass larger animals like grey kangaroos, forcing them to drop their joeys [babies] in fear."
Foxes also carry and transmit several diseases, eat and spread seeds from noxious weeds, and kill livestock.
A Desperate Race
Two foxes were shot in northern Tasmania in 2001; since then hundreds of sightings have been reported. What many had been dreading had happenedfoxes had made it onto the Ark.
There is evidence indicating that several litters of fox cubs were intentionallyand illegallysmuggled on to the island, reared, and then released at several locations across the state.
"It's more or less eco-terrorism," said Nick Mooney, scientific advisor to the Tasmanian Fox Free Taskforce set up in 2001 in response to the emergency.
Wildlife biologists estimate that there are probably 10 to 20 foxes currently in Tasmania. The taskforce has 21 full-time employees manning a telephone hotline, responding to reported sightings, conducting a statewide education campaign, and coordinating efforts to find the foxes and to prevent any further introductions.
The sense of urgency is motivated by the fact that foxes mate in winter, and most cubs are born in spring. Over the summer, which is December to February in the southern hemisphere, the fox cubs become independent and establish their own territories.
"It's a pretty important time, because if they've bred, now is when the pups will turn up," said Mooney. "If we can get through this summer and autumn without any sightings of pups, that will be great news."
So far no young foxes have been seen. But as Mooney points out, foxes are very secretive and quickly learn to avoid people and risky situations. This makes eradication by shooting impractical when the population is relatively small.
The taskforce made the difficult decision to use baits laced with poison in areas where the foxes have been reported. Using poison bait poses some danger to native fauna, but the alternative is much worse, said Mooney. Various safety measures, such as burying bait deeper than native species usually dig, have been put in place to minimize the threat to native carnivores.
"We need to have a whole community that understands how bad [having foxes in Tasmania] this is, so that it can't happen again," said Mooney. "As it is, we will have to stick at this [control program] for years, to make sure the foxes haven't established."
The stakes are high.
"If foxes establish, and native species are lost from their last remaining refuge in Tasmania, then there's no more hope for them," said Dickman. "Extinction really is forever."
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