Pesticides affect bees' spatial memories, finds study
Pesticides can affect bees’ spatial memories, causing them to forget where they’ve already foraged as they revisit flowers containing less nectar.
That’s the finding of a new study by scientists at Royal Holloway, University of London, which found that bees exposed to neonicotinoids were less able to forage effectively.
It also found that navigation was affected and valuable natural resources were being wasted by the bees.
Liz Samuelson, lead author and PhD student from the School of Biological Sciences at Royal Holloway, said: “Spatial memory is vitally important for foraging bees, which need to remember where good sources of nectar are but avoid revisiting flowers they have already depleted. Our finding that spatial memory is affected by pesticides suggests that bees exposed to these chemicals in the wild may be foraging less efficiently or even losing their way back to the nest.”
“There is growing evidence that pesticides are having harmful consequences for bees, with many studies showing that these classes of insecticide based have damaging effects on bee learning and memory. This is a concerning finding as it may mean bees are struggling to forage in the wild,” Samuelson added.
This research comes at a significant time for the pesticide debate, with the EU restrictions on neonicotinoid use currently under review.
The study was undertaken using a maze originally designed for rats to determine how effectively bees can remember which flowers they have visited. The less mistakes made, the better the spatial memory.
The research team is now looking at how humans may be having positive and negative effects on bee populations.
The report is published today in the journal Scientific Reports.