In the last two weeks, Australian authorities have exterminated millions of honeybees in a bid to prevent a potentially devastating parasitic plague affecting the southeast region of the country. The recent outbreak of the deadly varroa mite, a sesame seed-sized parasite that was first spotted at a port near Sydney last week, poses a massive threat to the country’s multimillion-dollar honey industry.
Colonies of honeybees have been put under “lockdown” as part of a wide range of biosecurity measures to limit the outbreak. “It is critically important that beekeepers in the Newcastle area do not move any hives or equipment in or out of the area,” said the Australian Honey Bee Industry Council.
Until recently, Australia was one of the few countries that was able to successfully clamp down on the spread of Varroa mite-induced plagues, known to be the biggest threat to bees worldwide. But this time, officials say that the tiny insect is here to stay.
What is the Varroa mite?
The Varroa mite, or Varroa destructor, is a parasitic insect that attacks and feeds on honeybees. Reddish-brown in colour, the tiny pests are known to kill entire colonies of honeybees, officials have warned. They often travel from bee to bee and also via beekeeping equipment, such as combs that have been extracted.
The spread of the mite is largely blamed for a sharp decline in the number of honey bee colonies worldwide. It has plundered bee colonies across the globe.
According to Australian beekeeping website Bee Aware (https://beeaware.org.au/archive-pest/varroa-mites/#ad-image-0): “Although Varroa mites can feed and live on adult honey bees, they mainly feed and reproduce on larvae and pupae in the developing brood, causing malformation and weakening of honey bees as well as transmitting numerous viruses.”
Over time, as the mite population increases in bee colonies, the symptoms grow more severe. Generally, heavy infestations lead to crippled bees, impaired flight performance, lower rate of return to the colony after foraging and reduced lifespan, Bee Aware states.
What do we know about the Varroa destructor outbreak in Australia?
The mite was first detected last week near the Port of Newcastle, The New York Times reported. Since then, the deadly insects have spread to over 400 different sites and over six million bees have been destroyed to rein in the contagion.
Soon after the Varroa Mite was detected in the country, authorities in New South Wales established strict biosecurity zones, limiting the movement of bees, hives, honey and comb until further notice in the affected areas.
Since then, Australian authorities have identified similar outbreaks in at least nine more locations — one of which was over 378 km away in the city of Dubbo.
While the mites do not feed on Australia’s native bees, several non-native species have been affected. Notably, the country’s honey industry primarily relies on these non-native bees.
Previously, the Australian government has been able to successfully eradicate similar incursions in 2016, 2019 and 2020, according to the Queensland Department of Agriculture and Fisheries.
Presently, the government is struggling to identify the location of all infected hives, Danny Le Feuvre, the acting head of the Australian Honey Bee Industrial Council, told The New York Times.
Why do bees matter?
According to a report by FT, the latest lockdown could adversely impact the growth of several crops — including almonds, macadamia nuts and blueberries — that are dependent on hives for pollination.
The varroa mite infestation comes at a time when the country’s agricultural industry is already dealing with a sharp increase in energy prices due to the Russia-Ukraine war, supply-chain issues, bushfires, floods and a recent mouse plague.