They have bright yellow legs, are about 25mm (almost 1in) long, and a single colony, if left unchecked, can “butcher” 90,000 pollinating insects in just one season.
Since the first UK sighting in 2016 of Vespa velutina – the Asian or yellow-legged hornet – beekeepers and scientists have waged a vigorous campaign to minimise the damage this invasive species can do to Britain’s biodiversity and bee colonies.
Last year, a wet spring and washout summer appeared to have hindered the insect’s population growth as the number of nests spotted in the UK dropped from 72 in 2023 to 24 in 2024. But it was also the first year that the National Bee Unit received confirmation, via DNA, that the hornets had successfully bred and over-wintered in the UK.