DNA testing has confirmed that Asian hornets overwintered in the UK for the first time this year, meaning it is very likely the bee-killing insect will be here for good.
Asian hornets (Vespa velutina) dismember and eat bees, and have thrived in France, where they have caused concern because of the number of insects killed. They sit outside honeybee hives and capture bees as they enter and exit, and chop up the smaller insects and feed their thoraxes to their young.
Previously they were not established in the UK, but earlier this year experts raised the alarm about a hornet that was captured in Kent in March.
Despite the Department for Environment, Food and Rural Affairs (Defra) saying earlier this month that there was no concrete proof the hornets had stayed here over winter, testing from the government-backed National Bee Unit has shown that three queen hornets caught at Four Oaks in East Sussex are the offspring of a nest destroyed in nearby Rye in November 2023. That implies that the hornets are here and breeding in the UK.
For the species to be classed as naturalised in the UK, however, the NBU says there needs to be evidence of a reproducing population present in the wild “for a significant number of generations”. Currently, only one generation of hornets has been found. “The presence of overwintered hornets produced from a nest found and destroyed late last year is not considered to be strong evidence of an established population,” it said.
Just one Asian hornet can hunt down and eat 30 to 50 honeybees in a day. Asian hornet numbers have skyrocketed in the UK, with 57 sightings in 2023, more than double the previous seven years combined.
It looks like 2024 may be an even better year for the hornet, with 15 confirmed sightings so far. Three sightings had been confirmed by the same date in 2023.
The species first came to Europe in 2004, when they were spotted in France, and it is thought they were accidentally transported in cargo from Asia. They rapidly spread across western Europe.
Defra has been contacted for comment.