New research suggests ground-nesting bees may be exposed to lethal levels of pervasive insecticides found in soil on farms across southern Ontario.
University of Guelph researchers examined the hoary squash bee that feeds on the nectar and pollen of squash, pumpkin, gourds and melon, and is a crucial pollinator for those crops.
They estimate 36 per cent of the bee population studied encountered lethal doses of one major insecticide in the soil at 18 commercial squash fields in southwestern Ontario.
That insecticide was detected in 96 per cent of soil samples and another insecticide was found in 81 per cent of soil samples tested.
Researchers have yet to determine exactly how much of the insecticides were absorbed by the bees – that will be the focus of a future study – but said the results were troubling.
University of Guelph professor Nigel Raine says the results indicate a major exposure risk.
The team’s results were published last week in the journal Scientific Reports.
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