Heatwaves may be affecting bees' ability to smell flowers

Heatwaves are impairing the ability of bumble bees to detect floral scents, posing a serious threat to their role as pollinators, according to a new study.

- STUTI MISHRA

The research shows that exposure to extreme temperatures can significantly reduce bees’ capacity to smell flowers, potentially disrupting their foraging behaviour and affecting the crops that depend on them for pollination.

Bumble bees are crucial to agriculture, pollinating crops that make up about a third of the food supply, including vegetables, fruits, nuts, and legumes. However, bee populations have been declining due to habitat loss and the climate crisis, with rising temperatures exacerbating the problem.

Researchers from the University of Wurzburg aimed to investigate how these rising temperatures impact bees’ ability to detect floral scents – a key factor in their ability to locate food. The research team conducted experiments on 190 bumble bees from two species, Bombus pascuorum and Bombus terrestris, both common in Europe.

The bees were subjected to simulated heatwaves by being placed in tubes where the temperature was raised to 40C for nearly three hours. Afterwards, their antennae were removed and attached to electrodes to measure their electrical responses to three floral scents: ocimene, geraniol, and nonanal. These scents are commonly found in flowers and play a vital role in attracting pollinators.