All bees - all pollinators, actually - are under stress these days, but bumblebees are especially affected by climate change, according to a new study.
Other species are mitigating the effects of warming by expanding their territories northward, but not bumblebees, found the study, published in Science. In fact, bumblebees appear to be contracting their territories.
"One of the important things to me was how many species are being impacted by climate change. That was a bit of a surprise," said York University Prof. Laurence Packer, an expert on bees and a co-author on the study with lead author Jeremy Kerr of the University of Ottawa, in a press release.
"I'd suspected some may be declining, but not such a large proportion. The fact that at the northern edges of their ranges they are not moving north as the climate changes is actually really quite worrying," he said.
Bumblebee species are dying out quickly, some as fast as a few decades, said the study.
"For the North American species that I work on, we know that about a third of them are in decline and in some cases this has been quite dramatically, more than 90 percent," says co-author York University Environmental Studies Prof. Sheila Colla in the release.
Colla added that even species that were widespread just 50 years ago are barely seen now, even within their normal range.
Climate change isn't the only factor killing off bees, experts say.
Tiffany Finck-Haynes, the pollinator expert for Friends of the Earth U.S., had this to say about the new finding: "The bee problem is complex; bees are having trouble for many reasons and the long equation of factors contributing to bee decline include: climate change, pests, disease, loss of habitat and pesticides. Pesticides are a key part of the problem and something in the equation we can fix right now. Reducing the use of pesticides will help bees."
The fact that there is a perfect storm of factors behind bee declines is a risk to the world's food supply and the U.S. government is starting to take action. In May, the Obama administration released a plan to make federal lands more friendly to bees, monarch butterflies and other pollinators.