About 30 per cent of British cropland – 3.14 million acres – was being treated with neonicotinoid chemicals in 2010.
Reports published in the journal Science on March 29th from British and French scientists, and extensively reported in the UK press today, confirm that both honey bees and bumble bees are seriously harmed by exposure to neonicotinoid insecticides, even by tiny doses not sufficient to kill them outright.
The British study led by Stirling’s Professor David Goulson looked at the impact on bumble bees and found that queen production was 85% lower in bees exposed to when exposed to “field-realistic levels” of imidacloprid than control nests not exposed to the chemical.
Mikaël Henry from France’s National Institute for Agronomic Research in Avignon led a study of honey bees exposed to another neonicotinoid product, thiamethoxam. The study found that at sub-lethal doses, “Non-lethal exposure… causes high mortality due to homing failure, at levels that could put a colony at risk of collapse,” by seriously affecting the bees’ homing abilities to the extent that they proved to be two to three times more likely to die while away from their nests than unexposed bees.