Australia Ramps up Bee Eradication as Varroa Mite Infestation Grows

A person holds a honeycomb cell for hive inspection at the Shangri-La Hotel in Sydney, Australia, on May 14, 2021. Lisa Maree Williams/Getty Images

The biosecurity zone in the state of New South Wales (NSW) continues to grow as more varroa mites were found in beehives in the Riverina and Sunraysia regions, prompting a new emergency order (pdf).

Varroa mite is an external parasite of adult honey bees and developing brood that can not only transmit honey bee viruses but can also weaken and kill the bee colony.

The varroa mites feed and live on adult honey bees, but are mostly found on larvae and pupae in the developing brood; which can lead to malformation such as scattered brood, crippled honey bees, impaired flight performance, and a reduced lifespan in affected honey bees.

The NSW Department of Primary Industries (DPI) announced on Aug. 24 that it had detected varroa mites in beehives at Euroley, Riverina and Euston, Sunraysia, where pollination is used for the almond and canola industry.

A 10 kilometre eradiation zone and a 25 kilometre surveillance zone are now in place, meaning hives cannot be moved into, within or out of these zones.

Any bees and their hives within the 10 kilometre eradication zone will be destroyed.

NSW DPI has prioritised tracing and testing of the hives, with new detections bringing the total number of infested premises to 215.

NSW DPI Chief Plant Protection Officer, Shane Hetherington in a media release that the new detection of varroa mites at Euston has links to an infested premises in the Kempsey area, which they were successfully able to track through the movement declaration process.

“We are continuing investigations into the link for the Euroley hives, although they have also travelled from the Kempsey region,” Mr. Hetherington said.

“Tracing and testing hives moved from the Kempsey region remains NSW DPI top priority, to ensure we can get in front of any further spread.”

Honeybees are seen at the J & P Apiary and Gentzel's Bees, Honey and Pollination Company in Homestead, Fla., on May 19, 2015. Joe Raedle/Getty Images

Varroa Mites In Neighbouring State

Biosecurity officers in the neighbouring state of Victoria have been extended into the state to be in line with the other varroa mite detections in NSW.

On Aug. 25, Agriculture Victoria updated the current varroa mite situation with the implementation of a 25 kilometre surveillance emergency zone established under the Victorian Control Area Order; with no movement allowed into, within or out of the zone.

All movement of bees and bee products (with the exception of processed honey and wax) is being regulated in Victoria through a permit system in order to prevent the entry and establishment of varroa mite.

Varroa mite has not been found in Victoria, and the state is committed to the National Response Plan and will be undertaking further surveillance in the region.

“We don’t take recent developments as a sign that eradication has failed or is not worth pursuing. That still remains the aim,” Federal Agriculture Minister Murray Watt told reporters on Aug. 25.

Mr. Watt also said the Albanese government was committed to working with all state and territory governments to eradicate the varroa mite and put a stop to threats to the honey and pollination industries.

Effect On Different Industries

The honey bee industry is vital to the almond industry for the cross-pollination of almond trees. They work together to use best practices and to provide a sustainable safe environment for honey bees to forage in almond orchards.

The Almond Board of Australia reported that in 2020 more than 70 percent of commercial bee hives in Queensland, NSW, Victoria, and South Australia were involved to pollinate the Australian almond trees.

Almond Board of Australia chief executive Tim Jackson told AAP that every August becomes the “biggest annual movement of livestock at one time in Australian agriculture,” and felt fortunate that almond flowering is ending and the bees were finishing their pollination job this year, with 300,000 hives from across the country involved.

Although almond pollination is finishing, Mr. Jackson said he was concerned about beekeepers who needed to move their hives onto new sources such as canola, macadamias, apples, avocados, and pears to pollinate in later months, or even national parks to keep them viable.

Further varroa mite infestations and hive movement bans could impact the livelihoods of bee hives and beekeepers, Mr. Jackson added.

Australian Honey Bee Industry Council reported on Aug. 25 that increased police presence has been coordinated in the affected NSW regions, with NSW DPI working with stakeholders to identify potential solutions to get hives off almond orchards and onto other crops.

Detection methods used to detect varroa mites include sugar shaking, alcohol washing and drone uncapping. Alcohol washing was recommended for beekeepers by BeeAware as a quick and affective method to detect for the presence of varroa mites using very little equipment, and can be easily performed during routine hive inspections.

The alcohol washing method (pdf) can remove 70-80 percent of external varroa mites on adult honey bees, and can also be used for Tropilaelaps mite and Braula fly surveillance, however, this method kills the bees that are sampled.

Since the first infestation that was found in Newcastle back in June 2022, beekeepers have been reporting hive locations and performing alcohol washes to look out for any signs of varroa mites to then report results.

On July 19, the NSW government announced $31 million ($19.9 million) to support beekeepers and the horticulture and cropping industries affected by the varroa mite outbreak.

The NSW government has already spent more than $33 million (US$21.1 million) to control varroa mite outbreaks, including $13.7 million (US$8.8 million) in reimbursement to around 2500 affected commercial and recreational beekeepers.

“The NSW Varroa mite response, led by NSW Department of Primary Industries (DPI), is the biggest plant pest response ever undertaken in NSW and as we pass the 1-year milestone we remain focused on the goal of eradicating the mite,” Minister for Agriculture Tara Moriarty said in a media release.

Prior to the first infestation in 2022, Australia was the last remaining major honey-producing country that was free from the varroa mite pest.