Spy tactics used to track killer Asian hornets and save Britain's bees

Wildlife experts have turned to spy-like tactics in a battle to save Britain's honeybees from invasive Asian hornets. Specially trained staff with the Animal and Plant Health Agency (APHA) have begun strapping miniature trackers onto the insect, which is also known as the yellow-legged hornet, in the last week.

This has drastically reduced the time and manpower needed to trace nests that need to be destroyed. There have been at least 104 credible sightings of the species so far this year, with at least 54 nests discovered.

Tracy Wilson, head of operational delivery for plant and bee health at APHA, said: "A yellow-legged hornet is not native to this country, so what we're trying to do is to retain the biosecure balance in this country by keeping them out. We are trying to keep out pests and diseases that are not naturally found in this county, and this is just another example of that."

Asian hornets, which reach the UK via accidental importation via goods, pose a significant risk to honeybees and other pollinators because of their predatory nature.

They can decimate honeybee colonies, impacting local ecosystems and agricultural pollination.

While not a major threat to human health, their stings can be dangerous to those with allergies or if multiple stings are received.

Dan Etheridge, a regional beekeeper, is among the first in the UK trialling the £80 ultra-lightweight tracking device developed by a Dutch company which is revolutionising the fight against the invasive Asian hornet across Europe.

He demonstrated how the full kit, which costs just over £2,000, has slashed the time taken to track a nest.

Speaking to the Express from a garden in Whitstable, Kent, where a nest was recently found, he told how a "bait station" - a tub of fruit juice-like concoction, is set up to lure the insect.

It is then humanely caught and fitted with a tiny device, weighing only 0.16 grams. It is essential that the hornet weighs a minimum of 350 milligrams with the tracker on.

Mr Etheridge said: "Obviously the bigger the better. As long as she makes weight, she's good to go."

He then fitted the device onto her waist, just behind her legs.

The animal is eventually released, but only after being placed in a "tent" where it is monitored to ensure it is unaffected by the tracker.

The APHA staff are then able to follow its journey back to the nest, which they can then destroy using insecticide.

This was the case following a discovery in Whitstable on Friday. The Express went along as both the hornet's primary and secondary nests were destroyed soon after a sighting by a local beekeeper.

He notified authorities about the sighting via the app Asian Hornet Watch, which allows users to report sightings with photos, dates and locations.

It comes as the frequency and volume of the sound from the nests of yellow-legged hornets, which originate from Southeast Asia, has been established for the first time by researchers at the University of Southampton.

This paves the way to faster detection and removal of their nests, which is experiencing a surge in numbers this year.

It also means that Asian hornet nests, which peak in numbers during September and October, can be detected and their sound used to distinguish them from the nests and hives of other wasps and bees.

University of Southampton's acoustic engineering graduate Sophie Gray said: "We observed and measured two Asian hornet nests and a European hornet nest in Jersey before they were destroyed. We found that the fundamental frequency is 125 Hz, and that the nest can be detected from about 20 metres away with a directional microphone.

"We also recorded European hornets and honeybees to determine if we can differentiate the frequency. The fundamental frequency of the European hornet is about 110 Hz, and honeybees about 210 Hz. It was great news to discover that the frequency is unique for each species, so they are distinguishable."

The main issue with Asian hornets is that they are omnivorous and feed on a wide range of pollinators to feed protein to their young, especially honeybees. One nest of Asian hornets can destroy an entire beehive in two to three days."

Asian hornets measure 1 to 1.5 inches long and are black with an orange stripe on the fourth segment of the abdomen, with legs that look like they have been dipped in yellow paint.