Warming global temperatures are having an increasing impact on our natural environment – some, like flooding, are more evident than others.

Asian hornets may not be an obvious consequence of changing temperatures, but because of warmer weather this non-native insect is now establishing itself in the UK with potentially devastating consequences.

The Asian hornet (vespa valutina, or yellow-legged hornet) is native to Southeast Asia and is a predatory wasp. It is a voracious hunter and represents a huge threat to native bee and insect populations.

It was first sighted in Europe in 2004 in the South West of France and is believed to have been accidentally imported with a consignment of pottery.

The species has spread rapidly across Europe with recorded sightings in most of the continent’s countries and it arrived in the UK in 2016.

Since then, as of the end of 2023, 75 Asian hornet nests were located, all of which were destroyed.

Most disturbingly, recent analysis has shown that Asian hornets have survived a UK winter for the first time.

The UK’s animal and plant health agency’s national bee unit carried out genetic testing and found that three Asian hornet queens were the offspring of hornets from a nest that was destroyed in November 2023.

Asian hornets will predate all local bees, other pollinators and spiders within a radius of 1.5km of their nest. It is estimated that honeybees make up around 30% of their diet, and that they can consume up to 50 bees in a day.

Not only are they adept at hunting, they are also incredibly effective at reproduction: it is estimated that around 6,000 hornets emerge from a nest, usually in the summer months, of which up to 200 will be queens. Compare this to the honeybee that has only one queen for every 40,000 to 60,000 bees.

There have not been any confirmed sightings of Asian hornets in the Isle of Man as yet, but it’s only a question of time before they arrive and so the Department of Environment, Food and Agriculture (DEFA) is well prepared.

They endorse the UK’s Department of Environment, Food and Rural Affairs (DEFRA)’s statement that early trapping is fundamental to eradication efforts, and they urge the public to report any sightings to them.

What does an Asian hornet look like? It has legs that are mainly yellow, with a brown/black abdomen (with one particularly thick yellow band), and a black/brown head, antennae and thorax; and an orange ‘face’.

A queen is up to 3cm long, and a worker up to 2.5 cm. They are never active at night. In comparison, the European hornet (vespa crabo) does fly at night and is attracted to light.

It has several thick yellow bands across its whole abdomen and a red/brown thorax. It is a native species and not considered to be a risk to pollinators.

DEFA are asking the Manx public to do the following if they come across an insect that they suspect may be an Asian hornet: contact their pest control officers immediately (telephone number 685894), take a photo or video if it’s safe to do so, and ascertain precise location details (ideally using the ‘what.3.words’ app).

They urge the public not to approach a nest, not to release a hornet if it is trapped (i.e. in a shed, or under a plant pot), or run away (Asian hornets may consider this to be a provocation, and they have a nasty sting – rated among the most painful of insect stings because it contains powerful neurotoxins).

A hornet’s sting usually causes a rash that may be itchy for a day or so. The stinger isn’t left in the skin, so there’s nothing to remove as there would be with a bee sting, and an effective home treatment is simply to apply ice to the affected area.

However, the toxins in the sting can trigger a severe allergic reaction in some people (up to 4% of the population).

Immediate medical attention should be sought if, after the sting, a person develops a tight chest, wheeziness, swelling in the throat, nausea or sweating.