UBC scientists say they have found a concerning number of non-native bumblebees across Metro Vancouver.
Bombus impatiens, the common eastern bumblebee, was originally imported from areas along the eastern seaboard into B.C. for use as pollinators inside greenhouses. In a UBC news release, biologists from the university’s Faculty of Land and Food Systems said they are alarmed to now find many eastern bumblebees in research surveys of the Lower Mainland.
“This tells us that they have been regularly escaping captivity, and that could be due to colonies not being destroyed each season according to guidelines. They now have reproducing populations that are sustaining themselves outside of any management here,” said Risa Sargent, who heads the Plant Pollinator and Global Change Lab.
Sargent said they don’t yet have direct evidence of the bees’ impacts, but scientists are concerned that the Bombus impatiens could threaten the wellbeing of native bees found in B.C.
“The more bees you have with overlapping floral resource use, the higher the chance for competition. We’re worried that the growing numbers of Bombus impatiens could reduce the population persistence and health of our native bees,” she said.
Native bees in both Japan and Chile have suffered population declines since the introduction of a different species of Bombus.
Sargent said she would like to see provincial incentives to enforce ‘decommissioning’ colonies once their first worker-cycle ends. She encourages B.C. residents to report sightings of the Bombus impatiens to a nonprofit social network for biodiversity, iNaturalist.