2 days ago
Asian buzz kill: The killer hornet threatening Europe's honey
A single hornet can kill up to 50 bees per day Euractiv is part of the Trust Project
The Asian hornet has terrorised Europe's honeybees – and their keepers – for over two decades. But scientists may have found a way to stop them from spreading.
The black-and-orange Vespa velutina , around three centimetres long with yellow legs, first arrived in France in 2004, likely hidden in a shipment of pottery from China. Since then, it has spread to a dozen other European countries.
Beekeepers in affected regions have reported hive losses of up to 50%, with each hornet able to kill 50 bees a day. And with several thousand hornets per nest the maths doesn't look good.
For Cyndy Adolphe, policy consultant at pollinator NGO BeeLife, it's a grim gift that France gave to the EU's beekeeping industry.
Last week, Ireland announced its second-ever sighting of the hornet and warned of a threat to biodiversity. Meanwhile, Belgian media reported that the region of Flanders is pouring millions into fighting the species, whose garden sightings have doubled this year.
Like wildfire
The insect's major threat to the European bee population is no secret to scientist, either.
'They spread like wildfire,' said Sophie Gray, a researcher at the University of Southampton in the UK.
A single hornet nest can wipe out an entire beehive in days – and they are not easy to spot as they can be underground, in bird boxes, bushes or perched 15 metres up a tree.
Global warming worsens the threat, allowing more hornets to survive winter and stay active from June to November.
'There is no respite for beekeepers any more,' Adolphe warned.
And the consequences are clear. In the worst-case scenario, Asian hornets are estimated to cost the French economy €30.8 million per year. Tracking the buzz
But Gray and her team believe they have discovered a breakthrough that could help solve these challenges: tracking the hornet's distinctive hum.
Their research shows that Asian hornets buzz at around 51 decibels, with a fundamental frequency of 125 Hz. Using a directional microphone, nests can be detected from up to 20 metres away – and can be distinguished from bees or European hornets.
The ability to quickly spot hornets nests may be a major breakthrough for beekeepers as it is a race against time once a hornet is spotted.
'It typically takes two to three days to find a nest after a sighting,' Gray explained. 'By then, the hornets may have wiped out a hive of 20,000 bees.'
With Europe's pollinators already under pressure, this new tool could enable to detect the killer buzz of the beekeepers' buzz killer early.
