The common crop pesticide thiamethoxam (neonicotinoid systemic pesticide) has been shown for the first time to seriously harm bees by damaging their renowned ability to navigate home.
The new research strongly links the pesticides to the serious decline in honey bee numbers in the US and UK – a drop of around 50% in the last 25 years. The losses pose a threat to food supplies as bees pollinate a third of the food we eat such as tomatoes, beans, apples and strawberries.
Scientists found that bees consuming one pesticide suffered an 85% loss in the number of queens their nests produced, while another study showed a doubling in "disappeared" bees – those that failed to return from food foraging trips. The significance of the new work, published Science, is that it is the first carried out in realistic, open-air conditions.