Australia-Rabbit numbers concern Farmers.
AUSTRALIA-RABBITS ARE BACK WITH A VENGENCE.
The researcher, Dr Brian Cooke, who was instrumental in the introduction of calicivirus (now called RHDV), has warned that rabbits are developing genetic resistance to the virus.
So Rabbitscan, which is intended to create a map of rabbits—and where rabbits are not—from at least 5,000 sites across Australia has moved centre stage in the latest phase of the 150-year old rabbit war.
It’s now a key part of a national fightback to offset the fall-off in the effectiveness of calicivirus.
In 1995, Quinyambie Station, SA, was carrying an estimated 20 million rabbits across its 12,000 square kilometres of sandy ridges, north-west of Broken Hill.
The fortunes of this rabbit-ravaged property began to turn around in October 1995, when the deadly rabbit calicivirus escaped controlled tests on Wardang Island and began to advance through the outback rabbit population at a steady 18 km a day.
By early 1996, the rabbit shooters, who had once been able to kill up to 400 rabbits a night on Quinyambie, had packed up and gone home, unable to find enough rabbits to keep themselves going.
For 13 years, Australia’s outback has had a good respite from the animal that was threatening to turn huge tracts of land into Sahara-like desert.
"There’s still patches of calicivirus around, but we’re seeing more and more rabbits coming back," said Paul Jonas, the current manager of Kidman-owned Quinyambie.
Mr Jonas said that even station owners in the Flinders Ranges, a region long in drought, are reporting that the bunnies seem to be coming back.
This is a nightmare scenario for Broken Hill station owner David Lord, who has waged a lifelong battle against rabbits on his property "Thackaringa".
As chairman of the Rabbit Management Advisory Group (RMAG), Mr Lord has devised what will be Australia’s first rabbit census.
Called The RabbitScan Challenge, the proposed map will become a benchmark from which to assess future population movements, and the basis for appeals for more investment in rabbit research and control.
During RabbitScan month, starting on May 1, anyone interested in spending a little time in the bush — schoolchildren, shooters, four-wheel-drive clubs, farmers — will be asked to conduct a survey of rabbits at selected sites and report their findings to a website, www.rabbitscan.net.au
Schools in particular are being encouraged to get involved, with special Teacher Kits available to help guide the exercise.
Using Google Earth technology, the collated information will be used to create a "rabbit map" of Australia.
"Australian agriculture is still losing $110 million every year to rabbits, " Mr Lord said.
"It’s been proven that one rabbit per hectare can suppress all regeneration of native vegetation.
"With anecdotal evidence that the effects of RHDV are declining, we need governments to fund the next wave of biological controls.
"Creating an evidence-based rabbit map is a step toward showing how rabbits are moving, and how populations might be changing."
The Invasive Animals Cooperative Research Centre (IACRC), co-funded by Australian Wool Innovation and Meat and Livestock Australia, is investigating why the effects of RHDV are patchy, and how to improve the effectiveness of the virus.
CRC researchers are also developing a new warren fumigator, using the cleaner and more humane carbon monoxide gas, and are working on a freeze-dried shelf stable RHDV product that will make it easier for land managers to introduce the virus to rabbit populations.
Pre-RHDV, Mr Lord said each warren on "Thackaringa" was carrying about 50 rabbits, with 10 rabbits known to eat the equivalent of what one sheep would eat.
When RHDV rampaged through the property in November 1995, it killed an estimated 750,000 rabbits, which were applying grazing pressure equivalent to about 75,000 sheep.
The RabbitScan project, as dreamed up by Mr Lord, is intended to provide the first evidence-based map of rabbits in Australia.
It is a strategy aimed at benchmarking rabbit populations and providing the basis for future funding of biological and other rabbit controls, hopefully preventing the world’s worst animal pest from repeating the collosal damage it caused to Australia during the 20th Century.
· www.rabbitscan.net.au
