Bumblebees could forget how to buzz because of pesticides, study finds (The Telegraph)
Originally published by the Telegraph
by Sarah Knapton
November 14, 2017
Bumblebees are forgetting how to buzz because of pesticides, a new study suggests.
Researchers at the University of Stirling found that neonicotinoid pesticides interfere with the vibrations of bumblebees as they collected pollen which, in turn, reduces the amount of pollen collected.
The team looked at ‘buzz pollination’ in which bees use vibrations to create an electrostatic charge which lifts pollen from flowers.
The scientists monitored colonies of bumblebees visiting buzz-pollinated flowers, monitoring their behaviour and collecting bee buzzes using microphones.
Dr Penelope Whitehorn, the University of Stirling Research Fellow who led the research, said: “Our result is the first to demonstrate quantitative changes in the type of buzzes produced by bees exposed to field-realistic levels of neonicotinoid.
“We also show that buzz pollinating bees exposed to the pesticide also collect fewer pollen grains.
“Control bees, who were not exposed to the pesticide, improved their pollen collection as they gained experience, which we interpreted as an ability to learn to buzz pollinate better.
“However, bees that came into contact with pesticide did not collect more pollen as they gained more experience, and by the end of the experiment collected between 47 per cent and 56 per cent less pollen compared to the control bees.”
Last week Michael Gove the Environment Secretary backed a Europe wide ban on bee-harming pesticides.
It follows a study in October which found that three-quarters of the honey produced around the world contains now nerve agent pesticides that can harm bees.
Scientists who tested 198 honey samples from every continent except Antarctica discovered that 75 per cent were laced with at least one of the neonicotinoid chemicals.
Dr Vallejo-Marin said: “Our findings have implications for the effects of pesticides on bee populations as well as the pollination services they provide. They also suggest that pesticide exposure may impair bees’ ability to perform complex behaviours, such as buzz pollination.
“The next step in this research would be to establish the mechanism by which the pesticide is affecting the bees. We think that pesticides may be affecting the memory and cognitive ability of bumblebees, which may be very important when conducting complex behaviours.”
Friends of the Earth nature campaigner Sandra Bell said: “This study adds to the overwhelming stack of evidence that neonicotinoid pesticides harm bees – this time showing that these chemicals could hamper bumblebee’s ability to pollinate some of our favourite fruits by buzz pollination.
“The new evidence comes hot on the heels of Michael Gove’s announcement last week that he will back further restrictions on bee harming pesticides. It further supports the UK’s decision – and should help other EU nations to make up their minds to back a Europe-wide comprehensive ban on these chemicals and find safer alternatives”.
The research was published in the journal Scientific Reports.