On Wednesday, June 22 2022, the varroa mite (Varroa Destructor) has been detected in biosecurity bee hives at the Port of Newcastle. The find is concerning and could have potentially devastating effect on the Australian apiary and agricultural industries.
The mites have been found in two of six control hives stationed at the Port of Melbourne to monitor diseases and functioning as early-warning systems. How the mites have made their way there is yet unknown, however a more detailed search has also found the mite on a commercial hive within 10 kilometers of the port. In response to the mite’s presence, the state government of New South Wales has issued a statewide emergency order to control the movement of bees across the state and hives within 10 kilometers of the Port of Newcastle are being destroyed. Financial support for affected beekeepers has already been promised and details are being worked out between the NSW government and industry representatives.
What is the varroa mite?
A parasitic mite, the varroa mite attacks and feeds on honeybees. The mite mainly feeds and reproduces on the larvae and pupae of honeybees. In addition, they also transmit numerous viruses.
Up until now, Australia was the only continent next to Antarctica that has been free of the parasite. Previous detections in Victoria and Queensland had been successfully eradicated. However, the previously detected mites were a less-threatening species. The ones found in the control hives are part of the varroa destructor species, which mainly targets the European honeybees, which form the mainstay of the Australian apiary industry.
Why is it an issue?
The detection of varroa mites is of particular concern in Australia, as it hasn’t previously seen wide-spread outbreaks of the parasite. Varroa destructor mainly targets the European honeybee which forms the majority of feral and commercial bees in Australia. The Australian bee is unlikely to be affected, however it was previously found that Australian European honeybee populations were particularly vulnerable to the mites, due not having been exposed before and showing very weak resistance.
Bees, both feral and commercial, form an important part of the Australian agricultural industry. Some 35 agricultural industries rely on bee pollination, including apples, berries, and almonds. A major varroa outbreak could cost the industry um to $70 million per year. Looking overseas, we get a good picture of the potential devastation an outbreak could cause. Following the incursion of the varroa mite on the US, about 30 per cent of commercial hives were lost, whilst New Zealand lost about 90 per cent of the feral bee colonies.
The mite is, however, not a death sentence to the bee colonies and the apiary industry as a whole. After an initial shock, there are way to manage the pest. Those measure will certainly add to the cost of production for beekeepers and agricultural producers though.
What now?
As the outbreak has only been detected recently, it is still too early to say whether the emergency order measures were successful and enough to contain the varroa mite. Beekeepers have been asked to self-assess and report back to the NSW Department of Primary Industries.
The varroa mite is a communicable disease in Australia and beekeepers are being urged to monitor their hives and contact the NSW DPI or the Commonwealth Department for Agriculture for further information or to report any suspicious outbreak.