Rising temperatures destroy bee population—inevitably damages US economy

Bumblebees, among the most important pollinators, are in trouble. Fuzzy and buzzy, they excel at spreading pollen and fertilizing many types of wild flora, as well as crucial agricultural crops like tomatoes, blueberries, and squash. But their numbers are dropping. New research using a massive dataset found that the insects are far less common than they used to be; in North America, you are nearly 50 percent less likely to see a bumblebee in any given area than you were prior to 1974. Moreover, several once-common species have disappeared from many areas they were once found, becoming locally extinct in those places. For example, the rusty patched bumblebee, which used to flourish in Ontario, is no longer found in all of Canada—. In a new , researchers used a complex modeling process to suggest that their decline is driven in large part by climate change. Specifically, the scientists found that in areas that have become hotter in the last generation, or have experienced more extreme temperature swings, bumblebees are less abundant. In Europe, they are 17 percent less plentiful than they were in the early 20th century. The scientists examined the abundance of 66 species across the two continents. The approach suggests “climate chaos” is a primary driver of the drop in bumblebees, says study leader , a doctoral student at the University of Ottawa. “These declines are linked to species being pushed beyond temperatures they haven’t previously had to tolerate,” Soroye says. Their disappearance from a region means that they’ve either moved elsewhere or died. Cool specialists It has long been known that bumblebees are more suited to cold weather, with their fuzzy bodies and ability to generate heat while flying, which often allows them to be the first bees out in the spring. Exactly how vulnerable they are to heat waves and weather fluctuations still isn’t clear for most species, though this study suggests there’s a limit to their adaptability. And it is indeed warming up. The last five years that the U.S. National Oceanic and Atmospheric Administration has tracked global heat. There are several mechanisms at play, says study co-author . The can simply overheat, as lab experiments have shown, but there may also be indirect impacts on vegetation and flowers that could lead to the bees starving, he adds. Bumblebees only live one year at most, and queens often spend the winter in leaf litter or in the ground. Here, they are still vulnerable to shifts in temperature, and things like unusually early ice melts and re-freezes, Kerr says. The decline is dangerous for the environment since bumblebees’ pollination services are necessary for many flowering plants to reproduce, says , a Ph.D. student and researcher at the University of Missouri in St. Louis who wasn't involved in the paper. “As these plants are then used by myriad other organisms, the decline of bumblebees can have cascading ecological [effects] that may collectively cause biodiversity loss.” There could also be economic costs. By one measure, to the U.S. economy by pollinating crops.