For the study, researchers assembled 110 years of data on 67 European and North American Bumblebee species to track their movements over time. Species observations were gathered from the Global Biodiversity Information Facility, following 171,479 North American and 192,039 European records. The data goes all the way back to 1901, and they wanted to look precisely at where each species was found decades ago, compared to recent years when climate change escalated. The scientists have analyzed what’s happening to the species’ geographical ranges under climate change and the substantial decline in bumblebees over the past few decades. They found the disappearance of the bumblebees might have something to do with rising temperatures, topped with a plethora of other factors including loss of habitat, pesticide use and parasites.
Biologist Jeremy Kerr, at the University of Ottawa looked specifically at the sightings, and said that given how other species have responded to warmer temperatures by moving northward, his team was “shocked” bees had not done the same. “We thought bumblebees would do that. Our results show very clearly that generally is not what they’re doing at all, they’re not expanding their range, unlike butterflies.” Bumblebee species are failing to migrate to warmer conditions to colonize new areas, and they’re simply losing the southern populations. The result suggests that the bumblebees’ range is being compressed across continents. While the bees moved to the cooler regions, they haven’t expanded to north at all to compensate for their disappearance in the south.
Bumblebees are believed to have originated some 35 million years ago. Since bees are more natives to cooler regions than tropical butterflies, scientists believe bees are maybe not as well-equipped to cope with warming temperatures. However, looking at how bumblebee species’ experienced range losses to warmest areas they historically occupied, in North America, while European species’ range losses extended across the warmest regions, it adds to scientists’ understanding that migration may not have occurred because they have trouble setting up homes in a new place. It’s surprising how different species respond to climate change. Research on the bees suggests that not all species have the same ability to adjust to new areas. Well, it’s also possible that the global climate issues that the planet has experienced so far isn’t enough to make them move, said Sydney Cameron, an entomologist at the University of Illinois. “It’s way too early to say they won’t move in the future just because they haven’t yet moved.”
It’s true climate change may be one of the greatest threats planet earth is facing, and with increasing extremities in weather patterns, chances for ecosystems to adapt naturally are diminishing. And Bumblebees are no exceptions. Climate change seems to contribute distinctively to accumulating range compression among bumblebee species across continents. Though, experimental relocation of colonies into new areas could contain these range losses, but it’s very unlikely that these efforts would do much good for the bumblebee species in the long term. Researchers expect the problem could get worse in the not-too-distant future, unless human population intervene to help them establish new populations in favorable environments. After all, Bumblebees help pollinate plants, wildflowers and fruit crops, as well as blueberries and tomatoes, contributing immeasurably to agriculture and wildlife.
They are the most important creatures in our food ecosystem and account for every one out of three foods we consume. Their significance can be gauged from the fact that Albert Einstein once said (no official records) that humans will have only four years to live if the bees left the world. Considering this, we have to act soon.