Climate change is waking bumblebees earlier from winter hibernation and causing death, study shows

Climate change can cause bumblebees to wake up too early from hibernation, which is likely to have a fatal outcome, a study finds. Since bumblebees are vital pollinators in agriculture, does it mean a disaster for human beings?

There is no good evidence that Albert Einstein actually said, “If the bee disappears from the surface of the Earth, man would have no more than four years left to live.” But the question implied in this pseudo-quote still stands: is it true that human life depends on bee pollination? Or, more precisely, to what extent does the quality of human life depend on bee pollination? These are legitimate questions, and it’s in everyone’s best interest to promulgate answers based on good biology and economics, not hyperbole, anecdote, or – as the Einstein pseudo-quote warns us – fiction.

Actually, what’s at stake here is not something so melodramatic as Einstein’s fictitious and dire warning about the collapse of Homo sapiens. Bee advocates do their cause a disservice when they stoke the flames of hyperbole and sensationalism. Much better to pose the question as a quality of life issue. To the extent that we value a diverse food supply with minimized trauma to the environments where it is produced, we will place a high value indeed on honey bees and other pollinators.

New research from the University of Ottawa published in Biological Conservation, this paper is one of the first to investigate the influence of climate change on seasonal climate changes in relation to bumblebees. Faculty of Science researchers have found that bees don’t change the timing of their activity accordingly earlier in the year, threatening their ability to find food sources or causing bees to miss them altogether .

“This study represents crucial groundwork for understanding that climate can impact the seasonal timing of biological events,” says lead author Olga Koppel, a PhD student in the Faculty of Science’s Department of Biology.

“Bumblebee survival is strongly in our best interest, as we rely heavily on bee-pollinated agricultural crops, including vegetables, fruits, and even clothing fibers such as cotton. The over 40 bumblebee species that are native to North America provide this invaluable economic service.”

Climate change is linked to the decline of global biodiversity and its impact on species is a growing area of ​​research. Climate change increases the likelihood of spring starting and blooming earlier in many areas, including spring plants, wild plants, and trees. They are a necessary food source for queen bumble bees that hibernate in the winter, foraging for pollen and nectar after waking up hungry and low on energy.

Being able to match floral resources over time gives bumblebee species an advantage. However, survival of those that emerge from hibernation before the arrival of spring flowers, their main food source, is unlikely, resulting in smaller colonies less likely to persist in that area the following year. Bumblebees that are in sync with spring weather changes make the most of the season’s floral resources and are more likely to persist over time.

Lead authors Koppel and Jeremy Kerr, senior lecturer and chair of the Department of Biology, examined the relationship between climate and the spring appearance of bumblebees in a database of specimens from North American museum collections, including 21 species and 17,000 individuals. The authors found that climate strongly explained variation in the timing of spring emergence in 15 of 21 bumblebee species.

“This research has shown that the timing of bumblebee emergence can be strongly skewed in the direction of climate change, which has implications for similar research on other species, as well as for the urgent conservation of these valuable species. of pollinators,” Koppel said. “This study provides a roadmap for assessing large-scale, temporary responses to climate change for many insects and other animals.

Reference: Olga Koppel et al, Strong phenological shifts among bumblebee species in North America can help predict extinction risk, Biological Conservation (2022). DOI: 10.1016/j.biocon.2022.109675