Change in Varroa mite response after eradication deemed no longer possible

The National Management Group confirmed yesterday that eradication of Varroa destructor was "no longer feasible based on technical grounds" and will now transition to a management strategy.

While a revised response plan, including transition to management activities, is being developed, NSW will operate under an interim strategy to limit the impacts and slow the spread of Varroa mite.

For more than 12 months, the hive-collapse causing parasite had been restricted to a 10,000-square-kilometre patch of NSW, with Newcastle at the epicentre.

However, things quickly changed in August, when the pest was discovered in hives at Kempsey.

More than 30,000 hives, holding up to one billion bees, were destroyed in the eradication process.

NSW Department of Primary Industries director-general Scott Hansen said that the detection in Kempsey was the tipping point for the change in response.

He said the length of time the mite had been in the Kempsey area, the high mite loading being detected, and traces coming out of the cluster had made it unfeasible to remain in a containment response.

"The factors around the Kempsey cluster provoked a series of discussions around how far it had spread and how long it might have been there," Mr Hansen said.

"We know that it's been in the Newcastle region for probably at least 18 months before it was picked up by the sentinel hives there.

"In looking at all of that and looking at the size of the containment areas now across NSW - we're talking in the vicinity of around 1.7 million hectares in red zones - it was felt that it's now too far widespread for us to be able to effectively eradicate."

Mr Hansen said that to assist the transition to a management response, some measures were put in place under an emergency order published yesterday afternoon.

"Transition to management has come with a series of goals from the national management group," he said. "They include slowing the spread and ensuring the spread remains contained to provide more and more time for the industry to have available their management options to help build their resilience and to help provide some pollination security going forward."

The eradication and surveillance zones, which have been in use since the first detection at Port of Newcastle, will change to a management zone and a suppression zone.

"The current eradication (red) zones at the Hunter/Central Coast and Kempsey will become two management zones where we will be actively managing the mite," Mr Hansen said.

"The rest of the state which is all of the current blue zone, all of the current purple zones and all of the regional outlier red zones, including eradication zones at Tamworth and in the Riverina and Sunraysia, will all become the suppression zone.

"People in the red zones who are yet to have their hives destroyed will have the option of choosing to have the hives euthanised and receive the compensation payment, or keep the hives, but have to follow a set of actions that include using miticide strips, which the DPI will supply."

It is estimated that moving to a management plan will impose a $5.2 billion cost on the industry, however Mr Hansen said the measures in place could significantly reduce that figure.

"The containment principles in the management response are driven by a number of factors, probably the largest one being the fact that it is still cost beneficial to eradicate if it was technically possible," he said.

"The $5.2 billion cost to Australia over a 30 year period of Varroa running free is able to be significantly mitigated against and reduced over that time frame if we're able to suppress it and reduce its spread and therefore its impact across the country.

"So the goal of suppressing it is largely about continuing to generate that benefit.

"At the same time, it is giving the industry time to do things like getting registered products available for miticide treatments which at the moment are available through the DPI and through other state governments.

"But we'll be working with the industry, with the federal government, with APVMA in ensuring we have some options available for producers as quickly as possible.

"We'll also be putting our efforts into assisting suppressing the mite so that we don't have as many beekeepers needing strips at this point in time."

Mr Hansen said NSW will still be operating under an interim response agreement.

"All the rules contained in the new emergency order around the zones, the rules around these zones, and what gets done, we're operating under that at the moment," he said.

"We'll continue to operate under that whilst a response plan for transition to management is prepared.

"There will be a new response plan with a new timeframe and a new set of goals, objectives, and triggers, but we're not at that point yet.

"We're at that point of this interim arrangement which will stay in place for a number of weeks whilst the other transition plan is built."

Colony loss will be an ongoing concern, with the United States reporting 48 per cent of colonies lost annually, while New Zealand reported 13pc.