Wild bumblebees across Canada face significant threats linked to agricultural methods, a new study out of York University finds.
Published in Conservation Science and Practice, the study examines how Canadian agricultural practices contribute to disease spillover from managed pollinator bees – used to support crop production – to wild bumblebees.
Led by Faculty of Science Professor Gordon Fitch along with York alum Amanda Liczner (PhD ’20), now with the Toronto and Region Conservation Authority, and the late Sheila Colla, Faculty of Environmental & Urban Change, the study’s findings raise urgent concerns for pollinator conservation.
The research team mapped areas across Canada where wild bumblebees are both diverse and are at high risk for population decline from pathogens transmitted by managed bees. Parts of Alberta, B.C. and southern Ontario – areas known for farming and rich ecosystems – were regions identified with the greatest risk for pathogen spillover in conservation priority areas.
“Bumblebees are essential pollinators and their populations are declining due to multiple stressors, including disease,” says Fitch. “Disease is a natural part of any ecosystem, but for bumblebees there is a big risk of new diseases spilling over from managed honeybee hives and wreaking havoc. Our findings show that many biodiversity hotspots for bumblebees overlap with areas of high disease spillover risk.”
To mitigate these threats to wild bumblebees, the researchers recommend regular screening of both managed and wild bees for pathogens as well as implementing biosecurity measures in agricultural settings. Further to that, the study highlights the need for preventative measures, including national monitoring programs and improved sanitation practices to reduce the spread of disease.
“Our research reflects York’s strong commitment to environmental sustainability and our work to protect biodiversity and ecosystem health,” says Fitch. “It also continues Dr. Sheila Colla’s legacy of combining rigorous science with advocacy to protect pollinators.”
Known for her pioneering work in pollinator conservation, Colla was a tireless advocate for native bee species and their habitats. This study is among her final contributions to the field and reflects her commitment to science that informs policy and practice.