THE deadly varroa mite has spread undetected across New South Wales bee colonies for more than eight months, pushing the industry to swap its eradication strategy for suppression amid warnings of significant population losses.
The invasive mite was first detected near the Port of Newcastle in June 2022.
Despite a $100 million effort to eliminate the pest and more than 30,000 hives euthanised over the past 14 months, scientific data and advice suggests the strategy is no longer workable.
The national management group attempting to contain the spread of varroa mite made a unanimous decision to transition its approach from eradication to managing the biosecurity issue.
It said the eradication strategy was made unviable by some keepers moving bees in containment zones and a spike in detections across a wider area, pushing control teams to the limit.
A significant outbreak at Kempsey on the Mid-North Coast was the final straw after tracing failed to detect the pest in some hives for at least eight months, NSW Department of Primary Industries director-general Scott Hansen said on Wednesday.
“That has allowed the mite to spread faster and further than what tracing has been able to keep up with,” Mr Hansen said.
Agriculture Victoria earlier this week said it was confident that Victoria remained free of varroa mite despite a recent outbreak just across the NSW border at Euston and Balranald.
Strong protections were initiated to guard against a future outbreak and a Control Area Order continues to restrict hive movements into Victoria as part of the response strategy guided by expert advice and scientific evidence.
Following the recent detections in southern NSW, Victoria has issued 146 permits to allow beekeepers to safely move out of the Surveillance Emergency Zones before the completion of almond flowering.
Surveillance was conducted last year to provide assurance that Victoria was free of varroa, with more than 5000 hives inspected, 83,000 hives in Sunraysia checked for certification and 52,000 permitted to be moved.
As part of the developments, an emergency order will split NSW into two zones as the state begins its next phase in the fight against varroa.
Hives within the Kempsey and Hunter regions will be placed under the management zone while a suppression zone will be set up for the rest of NSW.
Free movement will be allowed for hives within the management zone while those in the suppression zone will require a movement declaration.
Miticide strips, which contain chemicals that suppress the mites within the hives, will be applied to affected colonies in the management zones to allow keepers to continue their work without having to cull.
“Without eradication, we will be doing our best to suppress the spread,” Mr Hansen said.
“We are expecting it to continue to spread, however, across the countryside.”
The department will engage with industry stakeholders to provide education and management tools to beekeepers with the intention of suppressing the spread into other jurisdictions and building resilience.
Australian Honey Bee Council chief executive Danny Le Feuvre said he was disappointed the mite couldn’t be eradicated despite the emotional and financial sacrifice made by the industry.
Keepers are facing the prospect of colony losses as the mite spreads.
The varroa mite mainly feeds and reproduces on larvae and pupae, causing malformation and weakening of honey bees and transmitting numerous viruses.
“In other countries where they are managing it, significant colony losses have become the norm in their beekeeping operations,” Mr Le Feuvre said.
But he supported the shift in approach after 20 per cent of NSW hives in containment zones were in line to be euthanised before the change.
“If we were to continue down that path, it would have killed the industry,” he said.
Crop Pollination Association of Australia secretary Steve Fuller welcomed the call, telling AAP the decision to move to a management approach should have happened sooner.
Member for Mallee Anne Webster said growers and state governments, particularly NSW, could no longer shoulder the cost of the response.
“The presence of varroa mite in beehives just across the border from Mallee is a great concern for growers, and they should not be the ones carrying the costs to protect their crops,” she said.
“Eradication is always better than management.
“Agriculture Minister Murray Watt previously said varroa mite poses a real threat to honey bees and pollinated agriculture.
“At the very least, we need to ensure the management approach contains the threat within New South Wales and we fight to eradicate any future detections in Victoria.”
Dr Webster called for a review into how the eradication battle was lost with varroa mite in NSW “so we are better prepared for the next biosecurity incursion”.
Varroa mite had been found in hives at Euston and Balranald, originating from infestations traced to the Kempsey region, with the Port of Newcastle as its suspected origin.
– with AAP
