Stay alert for Asian hornets this autumn

Pest controllers are being urged to remain vigilant this autumn and report sightings of Asian hornets, as there is a chance they could be back, following the first confirmed case in the UK last September.

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Richard Moseley, Envu technical manager explains why the pests are likely to return this season.

“As part of the Asian hornet’s lifecycle, between August and October, fertilised queens leave the nest to find a secluded place to over-winter. This means that if they left before the nest was destroyed last September, they could have created a whole new population, which will peak in size again this autumn,” he says. 

“Additional Asian Hornets could also be introduced into the UK at any time from Europe via transported goods and vehicles” 

The reason why this is such an issue, is because of the threat posed to honeybee colonies. 

“Asian hornets hover outside a colony and prey on individuals as they return to the hive, or act as a barricade to stop the bees leaving, until they starve, meaning they can make their attack on the weakened inhabitants.

“Not only does this cause a problem for commercial bee keeping, but it also upsets the ecological pollinating role provided by bees. And as Europe has seen a decline in bee population in recent times, it’s important to protect them.”

Richard points out that it is essential that even professional pest controllers do not attempt to deal with an outbreak, until permission is granted by Defra and the Animal and Plant Health Agency (APHA) as they are still a reportable species being monitored by these agencies.

In addition to harming bees, the hornets can pose a risk to humans, as they are known to be aggressive and carry a nasty sting that has already caused six reported deaths from anaphylactic shock in France.

“When the sighting was confirmed last autumn, and the nest site discovered, Defra and the APHA approached Envu for guidance in their search for an appropriate insecticide to effectively treat the pests,” explains Richard.

“Ficam® D was the product that APHA chose to control this Asian hornet case, and they liaised with the Envu Pest Solutions Team on several occasions when planning the treatment, to ensure that this was the most suitable product for the target species,” he adds.  

The dust formula is ordinarily used to treat wasps and ants, as well as a wide range of other crawling and flying insects. It is specially designed to penetrate voids and spread inside spaces, being transferred around the nest by the insects, without irritation, making them less aggressive to the applicator. 

For more information on Asian hornets, and how to report a case please visit or to find out about Ficam® D, head to

Signs to look out for when identifying a case of Asian hornets:

  • Asian hornet nests can be considerably larger than a standard wasp nest
  • The nests are also often very high up in trees, but can also be found in buildings
  • While wasps enter from the bottom of the nest, Asian hornets’ entry points are around the sides of the nest
  • The Asian hornet is bigger in size than a wasp, but smaller than a European hornet
  • A dark brown or black velvety body, dark abdomen and yellow tipped legs are all characteristic of an Asian hornet