After the fires: beehive recovery

How are we helping bees affected by heat and smoke from the bushfires? Victoria’s Chief Plant Health Officer, Dr Rosa Crnov responds.

Most of us have seen the vision of wildlife, including koalas and kangaroos, injured in the latest bushfires, but bees were also in the path of destruction.

Statewide, the bushfires saw 134-plus hives from Gippsland to the Upper Murray destroyed. The recovery for Victoria’s $17.5 million apiary industry will take time.

That’s not great news for Australia’s crops, considering about 60 per cent of them are reliant on honey bee pollination.

As the Victorian Chief Plant Health Officer Rosa Crnov outlines, honey bees are essential for food security and agricultural exports through not only the production of honey and other bee products but most importantly, through crop pollination, a benefit which is valued nationally at $8.35 to $19.97 billion annually.

“Under normal summer conditions, bee colonies maintain an optimum hive temperature of 35 degrees Celsius by natural evaporative cooling using water that the bees collect,” says Rosa. “Should cooling fail under extreme heat conditions, the queen and worker bees can suffer heat stress and beeswax combs and honey may melt.

"Heat and smoke stressed colonies may take months to recover to full honey production and pollinating potential. Colonies with partial meltdown of combs can rebuild over time, but most colonies suffering total meltdown of combs or severe heat and smoke stress are unlikely to recover to production pollination strength and are likely to die.”

Burnt public land is impacting bees too, as about 70 per cent of honey production is derived from native flora species, many of which are located on public land. Compounding the issue, native forests play a significant role in conditioning hives for pollination, and recovery afterwards. Victoria’s public land apiculture policy provides 4554 apiary sites on 7.6 million hectares of forests, parks and conservation reserves.

“Victoria is committed to the future viability of our apiary industry and the agricultural and horticultural industries that rely on honey bee pollination, so we have been in constant contact with the Victorian Apiarists’ Association and Australian Honey Bee Industry Council to share information and provide support,” Rosa states. “Beekeeping clubs in affected areas are also being contacted to ensure they're aware of support services.”

Right now, beekeepers are helping to minimise losses and give affected bee colonies a better chance of survival through requeening, uniting disease-free weak colonies and by supplementary feeding with sugar syrup and a pollen supplement if a natural source of pollen and nectar can’t be accessed.

Come August, the most pressing issue will be the annual almond pollination season, which requires about 140,000 hives in Victoria. There aren’t enough hives here to meet pollination demand, so hives are trucked in from New South Wales, Queensland and South Australia. The high number of hives destroyed across Australia (for example, New South Wales has lost about 7000 hives from the summer fires), could impact the availability of pollination strength hives.

On a final note, Rosa says that in this, the International Year of Plant Health, it would be helpful for all Victorians to take a post-bushfire moment to reflect on our plant biosecurity system.

“Do not take it for granted – plant biosecurity ensures that we have safe and secure food to eat, and that our plant industries are profitable,” she advises.

And we need to be ever vigilant. Governments on a federal, state and local level are on the lookout for plant pests and diseases that can potentially devastate our agricultural industries and environment. One of the most serious threats at the moment is the exotic pest, the brown marmorated stink bug, which in 2019 was detected in Clayton, Dandenong and Port Melbourne. Fortunately, no further stink bugs have been detected.