Virus 'won't be the silver bullet we're all looking for'

Reports of high rabbit numbers around Central Otago and the Central Lakes district may be a thing of the past if a new strain of the rabbit calicivirus is approved by the Environmental Protection Authority.

Otago Regional Council director environmental monitoring and operations Scott MacLean said the New Zealand Rabbit Co-ordination Group (RCG), of which the ORC was a member, had submitted an application for the Korean strain of the calicivirus known as RHDV-1 K5 to be approved.

''We're hoping to get the go-ahead for an autumn bait drop, but if not there would be another window of opportunity in early spring when the rabbits were more likely to eat the infected carrots as there wasn't much fresh grass around and the temperature was optimal for the virus to work,'' Mr MacLean said.

He said the new strain would reduce rabbit numbers but warned it ''won't be the silver bullet we're all looking for''.

''It certainly won't wipe them out, but it should boost the effects of the existing calicivirus.

''We're sitting around 73% immunity to the current virus so we're hoping the new strain would boost the 27% who aren't susceptible to up to 40%.''

He said unfortunately the poor summer weather had not affected rabbit numbers and the ORC had received reports of high rabbit numbers in parks, reserves and along walking trails near Albert Town.

''Rabbit control in fringe or urban areas is really challenging as you can't shoot or poison them. The new virus should result in a drop in rabbit numbers in both of these areas but rabbit eradication is still going to require a long-term integrated approach. For a landowner or occupier, the best rabbit control remains rabbit-proof fencing,'' he said.

RHDV-1 K5 has already been been approved for use in Australia next month.