We know that the bees ain’t doing too well due to pesticides and even whack-arse bee houses! A new study, however, shed light on a whole new threat to bees: extreme weather. Turns out bumblebees are (unsurprisingly) another casualty of climate change, and that can be devastating to the ecosystems that rely on these little pollinators for reproduction.
Published in Science on Thursday, the study looked at 66 bumblebee species across North America and Europe. The authors compared baseline population data collected in 1901 and 1974 to more recent data between 2000 and 2014 using a model. They also examined the average of the five highest monthly maximum and the five lowest monthly minimum temperatures for their habitat areas during these time periods to gauge bees’ thermal limits as well as maximum and minimum precipitation.
The team, which included researchers from the University of Ottawa and University College London, found that bees were less likely to live in areas on both continents facing extreme heat than in previous years. More concerning, perhaps, is that bumblebees are not colonising new regions that fall within their thermal limits at the same rate at which they’re abandoning warmer areas. The pattern isn’t as pronounced for precipitation, though drier conditions did seem to negatively impact the species.
The probability of them occupying a region declined, on average, by 46 per cent in North America and 17 per cent in Europe between these two time periods. The authors were able to single out the impact of extreme heat from other factors that are hurting bees, such as habitat loss, by analysing the areas experiencing human land use in their model, too. While these changes also hurt the bees, this often happened separately from the heat. For instance, pesticides aren’t being sprayed in wilderness areas. But those places are feeling the effects of climate changes author Peter Soroye, a Ph.D candidate in biology at the University of Ottawa, explained to Earther. And the impacts of climate change, land use loss, and pesticides are happening at different rates, which helped the team isolate the impacts of climate change.
“All of these things are working together to drive extinction in bumblebees,” Soroye said.
Heat presents a unique threat to bees. Higher temperatures are pushing bees to their limits. These little guys can’t handle the level of heat that climate change has brought. The heat may cause them to have difficulty flying or overheat. They become more susceptible to predators, and they also struggle to find food. The heat can also prevent plants from growing, which the bees need to survive since they not only pollinate flowers; these buzzers eat pollen.
Unfortunately, bees aren’t the only insects suffering from the current state of environmental affairs. Wherever humans destroy habitat, many types of bugs suffer. So it goes with climate change, too. The same goes for wherever we install bright lights, which can confuse bugs. Beetles, nightcrawlers, and butterflies all have a sad story to tell, and all are reason for concern. People need bugs more than we like to realise.
We rely on bumblebees, in particular, to help pollinate crops like tomatoes and squash, Soroye said. And bumblebees are some of the most helpful bees when it comes to pollinating because they’re so big. Their big ol’ butts help physically shake pollen off flowers in the ways their smaller peers can’t always. Plus, they’re cute. That alone should be enough to convince the world to save them.
“Without them, we’re missing a little goodness in the world,” Soroye said.