At Mulligans Flat Woodland Sanctuary rabbits have the luxury of a predator-proof fence and immunity against deadly viruses that has left scientists in a stew for generations.
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They are being shot and fumigated at the 485 ha sanctuary on the edge of Forde, but with foxes, dogs and cats fenced out, plenty of cover from tonnes of dead timber dumped for native animals to shelter in, rabbits have more than a sporting chance to prevail.
ACT parks area manager for urban reserves Peter Galvin says there are hundreds of rabbits in the sanctuary.
"That is one of complexities dealing with the issue, understanding the rabbit's biology, their ability to breed quickly and respond to season conditions, and we are using a combination of strategies to get them in check," Mr Galvin said.
"In most cases outside of the sanctuary, the intention is to keep numbers in check, rather than eradicate them. It is all about a combination of strategies to not allow numbers to build up to a level where they are causing a great deal of environmental damage."
Controls can also include rabbit haemorrhagic disease (RHD), also known as rabbit calicivirus disease, and digging out burrows.
Rabbits are Australian agriculture's most expensive pest with annual costs exceeding $200 million. As few as 0.5 rabbits per hectare can remove seedlings and prevent natural regeneration in the bush.
NSW Department of Primary Industries researcher Dr Tarnya Cox say rabbit numbers have been slowly rising since drought-breaking rains in 2010-11.
A project leader for RHD Boost which is monitoring new strains of virus on rabbits, Dr Cox says some individual animals survive biological controls, because they are unable to be infected. These include kitten rabbits under 10 weeks of age.
"We don't understand why that is with kittens, but it is really hard to infect and kill a kitten with RHD, they tend to survive infection and become immune for life," Dr Cox said.
"That's how you start to build your immune population, then they breed and pass on maternal antibodies to their young and they last for about 12 weeks."
The RHD Boost project is looking for a strain that isn't recognised by antibodies. Researchers are taking a closer look in Europe where multiple strains roll through populations, and some strains out-compete others.
"The outside of the viruses are changing enough so that antibodies don't detect it," Dr Cox said. "That's what we are hoping to achieve by releasing new strains."