Vespa velutina – the yellow-legged Asian Hornet
This insect is not native to the UK and is NOTIFIABLE which means that, by law, you must report any sighting to the appropriate authority (see below). It was accidentally introduced to the south of France in 2004 and has quickly established itself across Europe.
The first yellow-legged Asian hornet nest in the UK was found and destroyed in 2016. There have been isolated sightings most years since. Asian hornet nests were first found in Hampshire in September 2018. The south coast is especially vulnerable because of cross-Channel traffic. Vigilance is absolutely essential because, once established, it is unlikely that we be able to eradicate this species.
The yellow-legged Asian hornet body is entirely dark and is velvet; the fourth abdominal segment is yellow and the legs are brown with yellow socks. The queen is up to 30 mm in length and is 7 mm wide.
A single queen will establish a colony early in spring and will raise thousands of worker hornets and hundreds of young queens, which will come through winter and start their own colonies.
Not just a problem for beekeepers
It is an extremely aggressive predator. A colony of Asian hornets will decimate a colony of honey bees in a few hours; but the Asian hornet is a voracious omnivore. It eats insects of any and every species and even carrion and road-kill. A colony of Asian hornets will reduce pollination so effectively that our native birds and small mammals will struggle to find food.
European hornet – Vespa crabro
Please note that European hornets (Vespa crabro) are native to UK and are not a threat to our pollinators. The European hornet abdomen is mostly yellow and orange. The legs have no yellow colouration. The queen is up to 35 mm in length and 8 mm wide – larger than the Asian hornet
Reporting a Sighting
If you think you have seen an Asian hornet anywhere in Great Britain, you must report it to the Non-Native Species Secretariat (NNSS).
The “Asian Hornet Watch” app is the most efficient method for reporting a potential sighting. You can download it for Android or iPhone. Take a photo of the suspected hornet, answer the questions as best you can, and send. NNSS will respond quickly.
Alternatively, you can use the NNSS online sighting form preferably attaching a photo.
Identification Aids
We recommend 2 excellent charts that will help distinguish between the Asian hornet and our native species:
- The National Bee Unit Asian hornet ID sheet that details the differences between the 2 hornet species, and
- BeeCraft magazine Asian hornet poster illustrating other species that are sometimes mistaken for the Asian hornet
Asian hornet traps
It is important, when monitoring or trapping Asian hornets, to be aware of their life cycle so that we do not inadvertently kill other, innocent species.
Mated queens emerge from February to seek food and start a new colony. At this time, we can monitor and trap queens; but be aware that other species with similar life cycles are at risk of harm. Traps must be placed where they are checked and emptied daily. If the trap contains a suspected Asian hornet, place the whole trap in a large polythene bag and seal it tightly, put it in a freezer and report your finding immediately (see above).
Worker hornets emerge later in the season, and bait stations can be set where they are easily monitored. These will attract various foraging insects. If an Asian hornet is seen, you can take a photo and send it to NNSS as above. Foraging hornets will return and their flight path can be plotted. Note that it is illegal for unlicensed members of the public in the UK to catch and release a notifiable species.
“Kill traps” are best suited when Asian hornets are actively predating a hive of honey bees.
Please go to the National Bee Unit website for current information.