RABBITS are back to pre-calicivirus levels across northern Victoria.
The rabbit plague has exploded into full bloom after the sodden end to the drought.
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The North-Central, Wimmera and Mallee regions are the worst hit so far as rabbits continue their relentless march south.
Scientists are at least two years away from releasing the next biological control.
Farmers have been told they are now the frontline troops as government teams are being dispatched to co-ordinate the fight.
Department of Primary Industries biosecurity manager for established animals John Matthews said the signs were all bad.
He said a control site at Bacchus Marsh had recorded 59 rabbits per linear kilometre before the release of calicivirus in 1995 and 19 per kilometre after the release. A recent recording found 73 rabbits per kilometre.
Likewise in the southern Mallee last week, DPI staff inspected 79 farms and will issue 25 direction notices to landowners, mainly for ripping burrows.
DPI staff had begun a rabbit compliance program in the Berriwillock area to support control works undertaken by the Landcare group.
DPI biosecurity area manager Sharyn Williams said "quite heavy pockets" of rabbits had been found, particularly in the area's sandy soils.
The inspection team detailed up to 50 active rabbit burrows per hectare in some spots. The threshold of an infested area is generally one to the hectare.
Mr Matthews said rabbits had enjoyed two "phenomenal" breeding years, thanks to the end of the drought.
As many as 70 per cent of young rabbits and 80 per cent of adult rabbits now had immunity to calicivirus and myxomatosis.
"Now we have to rip, fumigate and encourage each other to keep going."
Meanwhile, a Victorian Government roadshow will this month discuss research on RHD Boost, based around more potent strains of calicivirus which have been imported from Spain, France and Korea and are being tested at Sydney's Elizabeth Macarthur Agricultural Institute.
The roadshow visits Horsham today, Mildura tomorrow and Bairnsdale next week.
