A study published in the journal Science says that bumblebees are threatened by global warming. In North America and Europe the terrain were bumblebees live is shrunk by the global warming. According to the researchers the insects are losing range of their southern margin and in addition they cannot pick up territory at the northern margin. That is why their habitat range is getting smaller.
The researchers used records from between 1901 and 2010 and tracked 67 bumblebee species. The data set contained 423.000 observations. They also examined the changes in the territories where the bees live and the thermal ranges, the coolest and the warmest places. The scientists also created statistical models to test check whether the range shift could be explained by climate change.
They also considered that other factors besides global warming could be to blame for this phenomenon. That is why they looked at the use of pesticides like neonicotinoids and at the changes in land cover. The findings of the study indicate that the insects have lost about 300 kilometers (185 miles) from the southern end of their habitat on both continents starting with 1974.
The findings also indicate that actually global warming was the only factor which had an impact on the large-scale range shifts. The ranges began to shrink before people started using neonicotinoids according to Alana Pindar from the University of Guelph in Canada.
According to the lead author of the study Jeremy Kerr from the University of Ottawa in Canada global warming is crushing bumblebees “in a vice”. Bumblebees pollinate many plants which ensure food for both food and wildlife. The decline of these vital pollinators threatens food security and the economic viability of a number of crops.
Co-author of the study Leif Richardson from the University of Vermont remarked:
“Wild bumble bees are important pollinators of agricultural crops such as blueberry, apple, pumpkin and tomato, and declines in this ecosystem service of pollination could lead to lower crop yields and higher food costs, with consequences for both our food supply and the economy.”
The researchers urge that some measures should be taken in order to stop this process. Gardeners are recommended to plant more native wildflower. Governments could conserve more of their natural habitat and even move the bumblebee populations into more favorable areas.
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