Asian hornet invasion: a threat to honeybee survival
The spread of the invasive Asian ‘yellow legged’ hornet (Vespa velutina) across the UK is causing serious concern among wildlife experts. So much so, The Archers have woven the arrival of the insect into a storyline. This invasive species is a voracious predator and poses a significant threat to native insects.
An average Asian hornet nest can consume over 11kg of insects a year, including bees. They sit outside hives and capture bees as they enter and exit. The hornets then dismember the bees, chopping them up and feeding the thorax to their young.
It is estimated that one Asian hornet can eat up to 50 honeybees a day. But this devastating impact to beekeeping and honey production is not the only threat. The hornets also scare bees away from flowers and so undermine the stability of ecosystems. A study found that flower visits by bumblebees and hoverflies dropped substantially in the presence of these predators.
Colonisation
France first recorded the arrival of the Asian hornet in 2004. They are believed to have arrived in the Lot-et-Garonne département, in the southwest, via pottery imported from China. In 20 years they have colonised all of France and this year even Corsica. The speed of the colonisation and its impact is what worries governments, bee-keepers and environmentalists.
The Asian hornet was first recorded in the UK in 2016 near Tetbury in Gloucestershire. It is likely they crossed the Channel in cargo. But, with the help of the wind, they are perfectly capable of flying across.
In the first part of 2024 there were many sightings of the Asian hornet along the south coast including in Kent and East Sussex. The first nest this year was found at Barham near Canterbury. Since then 19 further nests have been confirmed in Kent, East and West Sussex and Hampshire. All were professionally destroyed.
With the vast majority of the sightings in Kent, Dave Goulson, Professor of Biology at Sussex University is worried the species may have already established itself in the county.
“It is a bit too early to say for sure, but the situation looks ominous, with a record nine nests found and destroyed this year so far,” Goulson said earlier this year. “If even one nest evades detection and reproduces it will then probably become impossible to prevent them establishing.
Search and destroy
The government’s strategy is to locate and kill every hornet and destroy all nests to prevent them from staying over winter and multiplying. As France has found, once the Asian hornet becomes established, it is proving impossible to eradicate them.
“It is too early to give up on control efforts,” says Matt Shardlow, chief executive of Buglife, an organisation dedicated to the conservation of invertibrates. “Removing nests has probably managed to slow its colonisation, and the abundance of different wasps can be strongly influenced by weather, so we can still hope that eradication efforts, perhaps with some lucky weather, might nip this colonisation in the bud.”
Identifying an Asian hornet
There are currently three species of hornet found in Europe. But only one, the European hornet (Vespa crabro) is native to Britain. It is our largest social wasp and poses very little threat to bees or humans. The European hornet is found widespread across England and Wales and occasionally will put in an appearance in Scotland and Northern Ireland.
Our native species is bigger than the Asian hornet. It has a black/brown thorax and an unbanded, yellow abdomen marked with brown on the upper part. Their head is yellow from the front and above with yellow antennae. It is their legs, which are dark at the ends, and their abdomen which are the key distinguishing features between the European hornet and Asian hornet.
The Asian hornet is active mainly between April and November (peak August/September) and is inactive over the winter.
For more help identifying Asian yellow-legged hornet, see the Non-Native Species Secretariat’s identification guide.
Reporting and staying safe
The Asian hornet will build very large nests in tall trees in urban and rural areas. They will also use garages and sheds as nesting sites.
It is essential an active nest is not disturbed.
“If you disturb a nest they will defend it vigorously,” says Asian hornet co-ordinator Alastair Christie, referring to an incident in Jersey where a nest was cut in two and agricultural workers were stung. “If you leave them alone, they leave you alone, but if you disturb their nest it can get quite serious.”
Vigilance is particularly required in southern parts of England and Wales and around major ports.
If you suspect you have an Asian hornet in your area please report suspected sightings with photographic evidence to the UK Centre for Ecology and Hydrology. Remember to include full location details.
