Climate change could deliver a fatal blow to the humble bumblebee.
Paired with other existing threats to the 250-plus species of bumblebee, new research has shown that climate change will result in extreme losses for many populations as they can’t adapt fast enough to ever-increasing temperatures.
The new study, reported in the journal Science this week, found that the likelihood of a bumblebee population surviving in any given place in Europe and North America has declined by 30 percent since the 1970s. According to the researchers, this rate of loss is “consistent with a mass extinction.”
“We were surprised by how much climate change has already caused bumblebee declines,” study co-author Dr Tim Newbold, from the UCL Centre for Biodiversity & Environment Research, said in a statement.
“Our findings suggest that much larger declines are likely if climate change accelerates in the coming years, showing that we need substantial efforts to reduce climate change if we are to preserve bumblebee diversity.”
The researchers examined data on 66 species of bumblebee across North America and Europe between 1900 and 2015. The data was then paired with information on temperature changes and different species’ tolerance to changing temperatures. This framework revealed one clear trend: populations are disappearing much faster in areas where temperatures have risen higher.
“Using our new measurement of climate change, we were able to predict changes both for individual species and for whole communities of bumblebees with a surprisingly high accuracy,” Peter Soroye, first author and ecologist from the University of Ottowa, explained in a statement.
In simple terms, parts of Central Europe have seen increasingly more frequent extreme warm years. The research shows that the rise in temperature is clearly correlated with declines in bees in certain pockets of Central Europe, most notably in Slovenia. By contrast, Italy’s temperature has remained relatively stable, as has the number of bees in the country.
Climate change is not the only threat to bumblebees. Declines in bumblebee populations have been shown to be linked to an array of causes, namely the reckless use of pesticides, disease, and the destruction of habitat.
Of course, this isn’t good news for us either. Over a third of the world's food crops rely on animal pollinators to reproduce. Effectively, one out of every three bites of fruit and veg we eat exists because of animal pollinators such as butterflies, birds, bats, beetles, and – last but not least – bees.
If unmitigated climate change manages to take out some of our planet's chief pollinators, the global food system will be put in serious danger.