http://www.digitaljournal.com/news/environment/study-finds-pesticides-badly-damage-bumblebees-ability-to-learn/article/460238

Pesticides damage bumblebees ability to learn, pollinate: study

Posted Mar 15, 2016 by Marcus Hondro
A new study has found yet more damage pesticides do to our food supply. The ability of bumblebees to pollinate human crops and wild plants is damaged by them, the study found, by disrupting their natural ability to learn.
Pollinators help pollinate over 75% of our flowering plants  and nearly 75% of our crops. So why are...
Pollinators help pollinate over 75% of our flowering plants, and nearly 75% of our crops. So why are we killing them?
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Bumblebees and pesticides
The study found pesticides somehow hamper the bumblebees ability to learn how to collect nectar and pollen. Published online in the British Ecological Society's journal Functional Ecology, it was co-authored by Professor Nigel Raine of Guelph University in Canada and scientist Dr. Dara Stanley of Royal Holloway University in London, England.
It is hardly surprising pesticides should be found to damage the ability of creatures in nature to carry out tasks but this is the first look at bumblebees and the effect certain common pesticides might have upon them.
Raine and Stanley's study found bumblebees exposed to pesticides actually went out foraging more often than did those in the control group who were not exposed to pesticides. However, the control group was able to gather more pollen in fewer visits to flowers than the exposed group.
Pollinating success
The control group also went more quickly to flower types that would yield the greater amount of pollen. For the researchers this is a warning that something in the toxic pesticides being used upon crops and wild plants is blocking the bees' ability to learn.
"Our results suggest the foraging behaviour of bumblebees on real flowers can be altered by sublethal exposure to field-realistic levels of pesticide," Raine and Stanley wrote. "This has implications for the foraging success and persistence of bumblebee colonies.
"But perhaps more importantly (it has implications) for the interactions between wild plants and flower-visiting insects and ability of bees to deliver the crucial pollination services to plants necessary for ecosystem functioning."
Both bumblebees and honeybees, also known to be adversely affected by pesticides, play crucial roles in the production of fruits and vegetables for humans and, through pollination, contribute to the making of food and shelter for birds and mammals.