Climate change means early flight start - risk of fewer bumblebees and reduced pollination

Published 1 March 2023

A bumblebee sits on a yellow flower. Photograph.

With the arrival of spring, bumblebee queens take their first wing beat of the season and set out to find new nesting sites. But they are flying earlier in the year as a result of warmer climate and changing agricultural landscape, new research shows.
– The risk is that we will lose additional bumblebee species and have reduced pollination of crops and wild plants, says researcher Maria Blasi Romero at the Center for Environmental and Climate Science and member of BECC.

When spring comes and the ground warms up, bumblebee queens wake up from hibernation. Contrary to workers and males, queens are the only bumblebees that survive the winter and they spend a couple of weeks to find a place to nest, where they can lay eggs and start a colony.

But rising temperatures mean that they wake up earlier in the year. New research shows that, in Sweden, the first flight occurs on average five days earlier than twenty years ago.

– Across Sweden, we see that the increased temperatures due to climate change clearly affect when the queens wake up and fly to find a new nest, says researcher Maria Blasi Romero.