Bees' biggest killer getting worse

While beekeeping in northeast Victoria has been already fundamentally reshaped by the arrival of varroa mite, a recent detection of pesticide‑resistant strains signals a significant escalation for the industry. “Beekeeping, as we know it, doesn't exist anymore,” Marraweeney beekeeper Andrew McCallum said. “It has just completely changed what we have to do, and the amount of work involved is, at this point for us, probably approaching tenfold what I was expecting it to be at this point in the season.” Mr McCallum is chair of the resources committee of the Victorian Apiary Association and also operates Raw Honey with his wife Moss, managing over 1500 hives across the state throughout the year. He told this masthead that they were now ‘pretty sure’ there were resistant varroa mite (Varroa destructor) in their hives. The couple began researching the parasite over a decade ago to ‘get ahead of the game’ but found the scale of the mite’s infestation far beyond their expectations. “The research did help, but it did not go even part of the way towards appreciating what it was actually going to be like. “When we found varroa in our own hives back in September, we thought ‘okay that means we monitor them, we have to start treating some’, but then what most people are experiencing now is that they don't really have any hives that are going to survive without some treatment. “The scale of that is just huge.” Authorities say the detection of resistant mites in the region now raises the stakes further. Beekeepers are being warned to closely monitor their hives after treatment‑resistant mite were detected in northeast Victoria. Testing of an apiary confirmed mites resistant to pyrethroid miticide treatments, with authorities believing the likely pathway was through hives moved from interstate last year and later sold to a Victorian beekeeper. Originally native to Asia, the parasitic varroa mite has spread globally since the late 20th century, devastating bee populations. It was first detected in Australia in 2022 and has since spread into Victoria, posing significant risks to pollination‑dependent industries and is expected to spread nationwide. According to AgVic, there are over fifty beekeepers and about 1500 hives registered in Strathbogie Shire and its immediate surrounds. Agriculture Victoria executive director biosecurity Charlotte Austin said on Monday 25 May the detection highlighted the need for vigilance among beekeepers. “Beekeepers are urged to regularly monitor mite levels in their hives to check that treatments are working, and rotate miticides with different chemical groups as part of best practice management,” Ms Austin said. “It is important beekeepers remain alert and let us know if their products do not appear to be working as expected.” She said AgVic was working with beekeepers to ensure they have the tools and knowledge to effectively manage the pest. “Victoria’s two-year Varroa Transition Program is supporting best-practice management, with Bee Biosecurity Officers and apiary inspectors available to provide practical advice. “Our Bee Biosecurity Officers provide hands-on help, including surveillance techniques, treatment options, and how to plan and schedule treatments.” Victoria transitioned from eradication to management of varroa mite following a 2023 decision by the National Management Group. Earlier this year, the destructive parasite was found to be resistant to pyrethroid and formamidine chemicals in New South Wales and Queensland. Further analysis is underway on the Victorian samples, with results expected later this month. For beekeepers on the ground, the economic impact is already being felt with pollination costs having risen sharply, increasing from around $30 to as much as $200 per pollination event in some industries. Almond and canola producers rely heavily on the hiring of hives, with industry experts warning the biggest impact will be seen in the price of fruit, nuts, and seed crops reliant on bee pollination. While honey prices have not yet surged - owing to favourable seasons and the pressure of matching imported honey prices - Mr McCallum said he expected production costs to increase. “If we just look at it in terms of our own production, with the current treatments that we have available to us at the moment, and the labour input required to administer them, it is very close to doubling our cost of production,” he said. Varroa mite is also expected to eliminate the country's entire 'feral' honeybee colonies (hives found in tree hollows and domestic cavities such as chimneys), meaning growers who once relied on free pollination will now face direct costs of hiring hives. Mr McCallum said the decline of feral colonies would also introduce 'mite bombing', as dying colonies began robbing commercial hives for honey, further infesting them with mites. He cautioned against hobbyists starting out with their first hives in the next few years, and had advice for anyone currently with hives. “Do an alcohol wash on your hive, and see if you've got mites, so you know if you need to treat it or not.” More information is available at agriculture.vic.gov.au and honeybee.org.au