Bumblebees have a remarkably successful method for fighting off Asian hornets, new research shows.
When attacked, buff-tailed bumblebees drop to the ground – taking the hornets down with them. This either causes the hornet to lose its grip, or the bee raises its sting and tussles until the hornet gives up.
University of Exeter scientists witnessed over 120 such attacks, and were stunned to find that bumblebees fought off the hornets every time.
Despite this, they found bumblebee colonies had reduced growth rates in areas with high numbers of Asian hornets – suggesting the hornets still had a negative impact, even if their attacks at colony entrances usually failed.
Asian hornets (also known as yellow-legged hornets) have already invaded much of mainland Europe and parts of east Asia, and have recently been reported in the US for the first time.
Sightings in the UK and continental Europe are at record levels this year – raising fears for pollinators and prompting substantial control efforts.
“Asian hornets prey on a wide range of insects, including honey bees, but little is known about their impact on other pollinators,” said Thomas O’Shea-Wheller, of the Environment and Sustainability Institute on Exeter’s Penryn Campus in Cornwall.
Read more at University of Exeter
Image: Asian hornets. Credit Sandra Rojas-Nossa