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Reuters/Nigel Roddis
Bees are in a very precarious position.
BUZZING

It’s confirmed: Pesticides are hurting bees

By Deena Shanker

Bees just can’t catch a break these days. Their falling numbers have been well documented, as have been the possible causes of that decline and the attempts to reverse their fortune. Winter is looking grim and a US Department of Agriculture scientist has alleged the agency silenced his warnings about the impacts of pesticides on their population.

The latest bad bee news: A new study finds that the most commonly used insecticide in the world is directly hurting bees’ ability to do their job as pollinators. Scientists have definitively confirmed the relationship between neonicotinoid pesticides, or “neonics,” to bees’ impaired functionality. The study, published in Nature this week, found that bumblebees exposed to the pesticides provided fewer “pollination services” to apples.

Although neonics were originally developed with the safety of non-target mammals in mind (e.g. a nearby deer or possum or the worker picking the apples), they are now regularly linked to the declining bee population. This study is the first to establish a direct causal impact of neonic exposure and pollination ability. The scientists exposed colonies to either the pesticide or a control substance for 13 days. They then brought the colonies to a field of virgin apple trees and Everest trees. At the end of the season, they tested apples to determine how well they were pollinated. They found the pesticide-exposed bees were visiting apple trees less and collecting less pollen. The apples from these trees then had fewer seeds, which the researchers say is a direct result of less pollination.

Bees are facing a war on all fronts. In addition to the pesticides, they are also beset by Varroa mites, which act like bee vampires, draining them of their bloodlike fluid and lowering their immune system. They are also dealing with major habitat loss, as biodiversity drops and natural landscapes are replaced with monocultures and residences.