A new virus introduced to fight plagues of the rabbit pest in Otago is taking effect, Radio New Zealand reports (HERE).
Field samples from the Otago Regional Council showed the K5 strain of the rabbit haemorrhagic disease is killing its targets.
The council’s director environmental monitoring and operations, Scott MacLean, welcomed the initial data but cautioned that the virus will not be widespread yet.
It will continue to spread for 12 to 14 weeks, he said. Land owners should plan secondary controls for winter.
Reporting earlier this year on the release of the rabbit virus across the country, including 100 sites in Otago, Stuff said officials hoped to kill more than 40 per cent of the pest population.
The Stuff report (HERE) explained that the K5 virus is a Korean variant of a strain that is already in New Zealand, after it was illegally released here in 1997 by a collective of vigilante Otago farmers.
Mr MacLean told Stuff at that time the approval of K5 was good news.
“Rabbits are the number one pest in Otago. Ten rabbits can eat as much grass as one sheep. They are a threat to our biodiversity, not to mention the soil degradation and loss of soil caused by rabbit holes and warrens.
“The K5 virus, which only affects the European rabbit, may give us the opportunity to reduce rabbit numbers to the level where they are manageable. It will be especially beneficial in areas where traditional rabbit management methods are either not possible or not acceptable.”
Environment Canterbury applied in November to the Ministry for Primary Industries for approval to introduce and use the Rabbit Haemorrhagic Virus Disease RHDV1-K5 for pest rabbit management.
ECan regional leader biosecurity Graham Sullivan said the virus would be released in March and April, but would not eradicate the population.
“While not the silver bullet for rabbit control, we anticipate that the new strain will greatly assist the control of wild rabbit populations by supplementing more traditional control methods.
“The controlled release will use a high-quality commercially prepared product at selected sites identified by participating local councils.”
The virus would be spread nationally in a coordinated programme. There would be more than 100 release sites in Otago and the council would coordinate the release to make sure it had maximum impact, MacLean said.
“These sites were selected based on science to ensure we have the best chance of creating an epidemic and a high knock-down (kill) rate.”
The virus is not being introduced without opposition.
Rabbit Council of New Zealand member Gary Stephenson, who submitted against ECan’s application, feared rabbit owners had not been given enough time to get their animals vaccinated against the “abhorrent” virus.
“There are thousands of rabbit owners up in arms and really, really worried about this … The pet rabbit population deserves the same care and protections from government and the animal welfare rights [groups] as pet cats and dogs … There are many other means of controlling wild rabbits that do not threaten pet rabbits or treat pet rabbits as collateral damage.
“I have been fighting this since June 2015 … It’s absolutely abhorrent.”
Mr Stephenson said it took 21 days for a vaccination to be effective, which did not give pet rabbit owners much time.
Rabbits infected with K5 develop symptoms between 24 hours and 72 hours after infection and usually die within six hours to 36 hours after the first symptoms appear.
More information can be found on the Ministry for Primary Industries’ website HERE.