What are Asian hornets? How to identify the bee-killer species

Sighting: Asian hornets prey on honey bees (PA)
Sighting: Asian hornets prey on honey bees (PA)

Sightings of Asian hornets are on the rise, raising fears that this invasive species could cause catastrophic consequences for the UK's bee populations.

They are causing havoc in mainland Europe. But nests have now been found in East Sussex, Kent, Devon and Dorset.

A report found that invasive species are a major threat to nature, food security and human health. They also contribute to 60% of global extinctions and costs are quadrupling every decade, reaching $423 billion (£336 billion) in 2019.

The solutions are said to be border and import controls. Though the Asian hornet poses no greater risk to human health than other wasps or hornets, the Department for the Environment says, it can cause damage to honey bee colonies and other insects.

Last month, a beekeeper found an Asian hornet in his garden, the insect's first appearance in London.

Asian hornet sightings are dramatically on the rise, with half of all sightings in the past seven years occurring this year. Almost 35 per cent of the reported sightings in the UK have occurred in August alone.

Londoners are asked to become familiar with the damaging species that feeds on honey bees so they can recognise it.

What are Asian hornets?

In 2004, a consignment of products imported from East Asia most likely contained Asian hornets, which were unintentionally delivered to France.

The species has rapidly expanded since it first arrived in France and is now spreading to nearby nations.

How are they a threat to bees in the UK?

The Asian hornet is a notable bee predator, which is cause for concern.

They have killed a significant amount of bees in France, including numerous species of solitary and colonial bees such as the well-known European honey bee. Since bees are a crucial part of healthy ecosystems, organisations dedicated to nature conservation, like the RSPB, are worried about how Asian hornets could affect bee populations.

As they’ve spread to nearby nations from France, the Asian hornets could also become a problem in the UK.

According to the Department for Environment, Food and Rural Affairs, there have been a total of 45 confirmed sightings of Asian hornets since 2016, with 22 confirmed sightings in 2023 alone. This figure includes a total of 29 nests, all of which were destroyed.

How do they compare to European hornets?

Asian hornets are smaller than our native European hornets and also have yellow tips on their legs. In comparison to our local hornet, which is 30 mm to 35 mm in length, an Asian hornet is frequently 25 mm to 30 mm long (or roughly 1 inch).

Another key difference is that while European hornets may be active at night, Asian hornets never are.

How to report an Asian hornet sighting

People will be able to swiftly and easily record potential sightings of the invasive species and transmit images of suspect insects to specialists at the National Bee Unit by using the free Asian Hornet Watch app.

You may get the Asian Hornet Watch app from the Apple and Android app stores.