Floral buzzing' to collect pollen as exhausting for bees as flight take-off, study shows

"Bees use as much energy collecting pollen through floral buzzing as they do taking off in flight, a study shows. Scientists have found the vibrations bumblebees use to shake pollen loose from flowers are among the most exhausting behaviours they perform, forcing bees to carefully choose which flowers are worth visiting. The study, released by the Royal Society, is the first to directly measure the energy cost of floral sonication, or buzz pollination where bees vibrate flowers to extract pollen."

"Using lasers and respirometry equipment to monitor three colonies of buff-tailed bumblebees, researchers discovered that a single buzzing event required about the same amount of energy as a flight take-off. Because buzzing can last longer, the total drain on energy can be even greater. Dr Beth Nicholls, principal research fellow at the University of Sussex, said: The findings suggest that floral buzzing could represent a major part of a bee's daily energy budget, something that has previously been overlooked."

"These results help us to better understand plant-pollinator relationships and just how hard at work a buzzing bee really is. In 2024, the number of bumblebees in the UK declined by almost a quarter compared with the 2010-2023 average, according to the Bumblebee Conservation Trust. The researchers said the drop was probably due to the cold and wet conditions in the UK that spring. Despite a rebound in 2025, numbers for many species are still below average."

"The study said: As nectar availability shifts due to climate change or habitat loss, the energetic demands of pollination could influence bee behaviour and, ultimately, where bees forage and which plants they pollinate. The research said that the finding challenges the common assumption that flight dominates bee energy budgets. The metabolic rate of a "

Bumblebees vibrate flowers to release pollen through floral sonication, also called buzz pollination. Measurements show that a single buzzing event requires about the same energy as taking off in flight. Because buzzing can continue for longer periods, the overall energy drain can be even greater. Researchers used lasers and respirometry equipment to monitor three colonies of buff-tailed bumblebees and directly quantify the energy cost of buzzing. The results indicate that floral buzzing can represent a major portion of a bee’s daily energy budget, which has been previously underestimated. As nectar availability changes due to climate change or habitat loss, these energetic demands can influence where bees forage and which plants they pollinate. The findings also challenge the assumption that flight is the dominant driver of bee energy use.

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