UK bumblebees suffer steep population declines as heatwaves intensify

New analysis from the Bumblebee Conservation Trust shows that recent UK heatwaves are causing severe stress to native bumblebee species. When air temperatures rise above 28 °C to 32 °C, the insects’ muscles generate excess heat and their thick coats prevent cooling, leading to overheating and death. Data from the BeeWalk monitoring program recorded a sharp drop in numbers after the record‑breaking 2022 heatwave, with red‑tailed, buff‑tailed and common carder bumblebees falling 20 %, 25 % and 35 % respectively, and queen counts remaining below average into spring 2023.

Experts warn that extreme heat combined with drought reduces flowering plant availability, forcing bees to expend energy without sufficient nectar or pollen. The result is slower larval development, weaker colonies and fewer new queens for the next season. Conservationists recommend creating flower‑rich habitats to provide food sources as climate‑driven heatwaves become more frequent and intense.