A large study published in Science this week shows that common pesticides known as “neonics” can harm bee colonies, despite the claim of the chemicals’ maker Bayer that there are no adverse effects to bee colonies.
Bayer has been criticizing studies demonizing its products for being conducted in artificial conditions instead of the real world. The latest study, however, makes it harder for the German chemicals company to defend its neonicotinoid pesticides.
The recent study, which was carried out outside laboratory conditions, found that honeybees and a couple of wild bee species are negatively impacted by the pesticides. Neonics are usually placed on plants’ seeds to shield them against pests.
Scientists analyzed bees’ health and behavior when exposed to two types of canola crops: one was treated with Bayer’s products and a fungicide, while the other was treated only with the fungicide.
Researchers found that bees who were exposed to neonic-treated crops reproduced at a slower rate and their colonies had lower chance of surviving the winter. Lead author of the study Richard Pywell, who works at the Centre for Ecology & Hydrology in the U.K., deemed the findings “cause for concern”.
A Notable Exception
The research also revealed that bees living in Germany were not influenced by the pesticide. In fact, the chemical seemed to help them produce more eggs and more larvae.
Pywell noted that this exception doesn’t invalidate his findings. He thinks that the situation in Germany could help other scientists explain the inconsistency of previous studies. The researcher thinks that the local environment has a lot to do with how much neonics affect a bee colony.
The research team couldn’t tell what factors in the environment may influence results but they have some suggestions. For instance, honeybees in Germany were able to feed from multiple sources not just canola. While, in other parts of Europe, half of the collected pollen was from neonic-treated canola, in Germany that figure dropped to just 10%.
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