Exposure to systemic neonicotinoid pesticides causes queen bumblebees to lay 26 percent fewer eggs. That rate of decline could result in the extinction of some wild bumblebee populations, according to researchers at the University of Guelph.
Nonlethal exposure has significant impacts, new study shows
The evidence keeps mounting that pesticides are the main driver of honey bee declines. In a new study, scientists with the University of California San Diego showed that a commonly used neonicotinoid pesticide (thiamethoxam) can significantly impair the ability of otherwise healthy honey bees to fly, raising concerns about how pesticides affect their capacity to pollinate and the long-term effects on the health of honey bee colonies.
It’s no secret that various pesticides are killing bees in many different ways, despite all the lies from chemical companies trying to make you think otherwise. In that battle for truth, and ultimately justice, more science helps, and researchers from the University of Guelph have show now systemic neonicotinoids reduce egg production in wild queen bumblebees.
“Queen bees will only lay eggs when the eggs are fully developed,” said Prof. Nigel Raine, holder of the Rebanks Family Chair in Pollinator Conservation. If queens need to use energy to clear pesticides from their system instead of investing in eggs, then fewer fully developed eggs will result, he said. “This will likely translate into slower egg-laying rates, which will then impede colony development and growth.” Continue reading “Neonicotinoids impede bumblebee egg production”→
Systemic pesticides seen to affect hives in various ways
A new study led by a University of Nebraska-Lincoln entomologist reinforces the link between neonicotinoid pesticides and declining honeybee colonies. The researchers experimentally fed queen bees with a syrup laced with imidacloprid, finding that queens laid significantly fewer eggs than queens in unexposed colonies.
“The queens are of particular importance because they’re the only reproductive individual laying eggs in the colony,” said lead author Judy Wu-Smart, assistant professor of entomology. “One queen can lay up to 1,000 eggs a day. If her ability to lay eggs is reduced, that is a subtle effect that isn’t (immediately) noticeable but translates to really dramatic consequences for the colony.” Continue reading “Queen bees exposed to neonicotinoids lay fewer eggs”→
The study, published in the journal Nature Communications, analyzed changes in the population of 62 wild bee species, comparing them with patters of oilseed rape crops between 1994 and 2011, as the use of commercial use of neonicotinoids became widespread.
The findings suggest that systemic pesticides contributed to a “large-scale and long-term decline” in wild bee species distributions and communities. Species that regularly forage on treated rape fields declined, on average, three times as much as species that feed on a wider variety of plants, showing that oilseed rape is a principle mechanism of neonicotinoid exposure among wild bee communities. Continue reading “Neonicotinoid pesticides implicated in decline of wild bees across the UK”→
Government Accountability Office highlights needs for more research on pesticide impacts
U.S. government investigators said the EPA and the Department of Agriculture need to take more steps to address threats to wild bee populations, starting with a better monitoring program to assess the impacts of agricultural pesticides.