Tests from field samples in Otago indicate mortality as a result of the RHDV1 K5 rabbit virus.

ORC director of environmental monitoring and operations Scott MacLean said while this is excellent news, the virus won’t be widespread at this stage.

“There’s a difference between the natural spread of the virus that’s been released now, and the illegal release back in 1997.

“If a virus isn’t left to spread naturally you’ll see a big impact at the start but this will drop off quickly. If it’s left to spread naturally you’ll see the peak around four weeks after the release, and we’re close to that timeframe now. It will continue to spread for 12-14 weeks after it’s been released,” Mr MacLean said.

“Now is the time for land owners to plan secondary control for rabbits that they can carry out over winter. By then the virus should be well established, and winter is also the optimal season for rabbit control,” he said.

The K5 virus is spread from rabbit-to-rabbit contact and also through flies acting as a vector, and land owners are reminded to not intervene.

“Human intervention can potentially result in rabbits becoming immune to the virus, so people need to be patient and leave any rabbit carcasses in place so the virus can take hold biologically.

“This not only gives the virus the best chance to be effective, but also means it will have a better ongoing impact for years to come,” Mr MacLean said.

Farmers who are noticing dead rabbits on their property are asked to contact a biosecurity officer at ORC on 0800 474 082 so samples can be taken for testing.

ORC expects the virus to spread in a 20km radius from each of the 100 release sites throughout Otago over the next couple of months, which will cover the majority of Otago.

Traditional rabbit management methods won’t be replaced by the virus, and secondary control is important to keep rabbit numbers down. Information can be found on the ORC website here.