Australia-The rabbits are back causing nightmares for farmers.

AUSTRALIA-THE RABBITS ARE BACK.

Rabbit populations in Queensland have begun to rise with the biological controls that saw rabbit numbers decimated in the late 1990s, now ineffective as the animals gain genetic resistance.

The first wave of biological controls were brought about in the 1950s in the form of myxomatosis; however, there was a long break before Dr Brian Cooke oversaw the release rabbit haemorrhagic disease (calicivirus) in 1995.

Through his detailed research Dr Cooke said at the time the virus would likely have a lifetime of 10-15 years before rabbits gained immunity.

Now 14 years later, no new biological controls have been found, however zoologists and field researchers with the DPI&F have been working hard monitoring the spread and increase of the rabbit.

The introduction of calicivirus saw a 70 percent reduction in the rabbit populations in Queensland around 10 years ago during the peak effectiveness of the virus.

"Over the past five years there have been big increases in rabbit populations in Queensland," said David Berman, DPI&F Biosecurity Queensland senior zoologist.

"Calicivirus is still suppressing the population, but we’ve got evidence that they are gradually developing genetic resistance to calsesi, similar to what happened to myxomatosis."

For a pest animal that was so wide- spread the use of biological controls have been effective - however people have become reliant on them.

"There is work being done to research and test current existing biological controls from across the world and see if they are suitable.

"These processes are slow and these things won’t happen quickly, however we’ve got chances of finding new agents," said Jim Thompson, DPI&F Director for Biosecurity Science.

DPI&F field officers have reported an increase of rabbits in north Queensland around the Atherton Tablelands, areas previously sparsely or uninhabited by rabbits.

"We have options and now is the time to do something before rabbit populations become too large," Mr Thompson said.

David Berman who has specialised in controlling rabbits said the best way to reduce rabbit populations on property is to rip the warrens with a bulldozer, which destroys the place they are breeding and can have a long-term effect on their numbers.

During the late-1990s Mr Berman carried out extensive research and rabbit control methods on Bullo Downs in western Queensland.

Through his research it was found that rabbit infestations were costing Bullo Downs $600,000 in lost production before the warrens were ripped and the rabbits lost their base for breeding.

"As soon as you take the rabbits away you notice the green pick coming up ? the insects come on to the green pick and you see an increase in native animals," Mr Berman said.

"We showed that on the sand dunes at Bullo Downs that the rabbits were taking nearly all the vegetation and the cattle were getting nothing.

"Once the rabbits were taken away there was a large area of the property that the cattle were able to graze," he said.

The current research being carried out by Mr Berman and his team focuses around the Eukey/Stanthorpe region to determine if populations are reduced in key areas, whether this has an effect over much larger areas.

"We’re estimating the work in key areas will reduce rabbits in a 50km radius," Mr Berman said.

"As rabbits can travel up to 70km we’re hopeful this research will prove correct."