It's Invasive Species Week – a time to look at the impact invasive non-native species are having on our native wildlife in various environments. Our Nature Policy Officer, Sarah Hudson, takes a look at Asian hornet – an invasive species on the brink of gaining a foothold in the UK.

Why are we worried about Asian hornets?

The Asian hornet (Vespa velutina) is native to China but arrived in Europe in 2004 and is now widespread in parts of France, Spain, the Channel Islands and Portugal. It is smaller than our native hornet (Vespa crabro) and poses no greater risk to human health than other hornets or bees. However, it does pose a risk to honey bees and pollinating insects, being a significant predator of species which are already struggling. Declines have been reported for all key insect pollinator groups including honeybees, bumblebees and hoverflies, making the added predation pressure of Asian hornet particularly worrying.

Asian hornets arrived in the UK for the first time in 2016 and sightings have been reported each year since then. Officials have been working to find and eradicate the hornets before they can spread and become established.

How to identify Asian hornets

Asian hornet (c) Gilles San Martin (Flickr - CC-BY-SA 2.0)

There are several key features which distinguish Asian hornets from our native European hornet:

  • The Asian hornet is smaller, with queens up to 30 mm, and workers up to 25 mm in length. European hornet queens can reach 35 mm.
  • Asian hornets have an almost entirely dark abdomen except for the end segment, which is yellow. European hornets have a brown and yellow striped abdomen (similar to a common wasp).
  • While the legs of European hornets are dark, Asian hornets have bright yellow tips to their legs.

  

Further information can be found on this factsheet and poster.

How you can help

It would be extremely difficult to halt the spread of Asian hornets if they establish permanent populations in the UK. The Government Department, DEFRA (Department for Environment, Food and Rural Affairs), is attempting to prevent this by asking the public to report any possible sighting of the insects so that they can be removed as quickly as possible.

You can report suspected sightings of Asian hornet in the following ways:

  • Through the free Asian Hornet Watch app, available on the Apple App Store and the Google Play Store. It offers a guide to identifying the insects as well as an option to report a sighting.
  • Sightings and images of the hornet can be submitted directly to the Biological Records Centre (BRC) through this online form.
  • Email details including location, and photo if possible, to alertnonnative@ceh.ac.uk

If the nests can be detected at the early stages of invasion, there is a real chance that we can prevent the establishment of Asian hornets in the UK and reduce the threat facing our native pollinators. 

For more information on Invasive Non-Native Species, the threats they pose and how you can help stop the spread, take a look at our interactive storymap and follow @invasivesp on Twitter.

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