Bumblebee Disappearance Caused by Climate Change, Study Finds

A study published Thursday in the journal Science points to global warming as a major factor in the die-offs of bumblebee populations in North America and Europe. According to the study, which looked at museum records of 67 species of bumblebees over the course of 110 years—which included 420,000 total observations—about a third of North American bumblebees are in decline, though one of the study's co-authors, York University environmental studies professor Sheila Colla explained that, in some cases, "more than 90 percent" of the species have been negatively impacted.

Bumblebees are crucial to maintaining biodiversity in the regions they inhabit. Pollination by insects is critical to producing around a third of the food humans consume. Unlike other species, which adapt to warming temperatures by moving north into cooler "ranges," bees have tended to stay put. As a result, huge swaths of bumblebee populations are dying off. And quickly.

"One of the scariest parts of the work that I've done is just realizing how quickly the situation is changing," Colla said in a press release. "The bumblebees that are in decline were doing fine 50 years ago. We're talking about large changes in community composition of essential pollinators over just a few decades."

The study also indicates what many climate change deniers have likely ignored: that the deaths are the direct result of global warming, and not pesticide usage or habitat demolition.

Another co-author of the study, Jeremy Kerr, a professor at the University of Ottawa, put it more bluntly: "These species are at serious and immediate risk, for rapid human-induced climate change." In fact, two species of bumblebee (Cullem's bumblebee and the short-haired bumblebee) have already gone completely extinct in the U.K. in the last century, and many more are threatened. "The impacts [of bee die-offs] are large and they are under way," Kerr told the BBC. "They are not just something to worry about at some vague future time."

The study's authors say that humans may be bumblebees' last hope for survival, and that assisting the migration of bees to cooler climates could be beneficial. Though this is not a guaranteed solution, as the bees' preferences and adaptability vary widely by species, Kerr expressed tempered optimism: "If we are serious about preserving species like bumblebees for the future, it is possible we will need to intervene in a significant and extensive way to help them adapt."