The bees may be developing a nicotine addiction in the same way that humans become addicted to cigarettes, according to new research. As well as developing an addiction, reproduction and colony growth in certain bee species may also be affected by exposure to neonicotinoids, writes Ben Hirschler for Reuters.
Research shows bees prefer water containing pesticide
In Europe there are restrictions on three pesticides of this type because of concerns about bees. However debate continues to rage over the impact that low doses of pesticides have on bees and other non-target insects. Neonicotinoids are made by companies such as Bayer and Syngenta, and advocates claim that they kill pests and increase crop yields.
Critics have voiced concerns that they may contribute to a decline in bee populations, which are crucial for crop pollination.
Researchers offered bees a choice of drinking water laced with sugar or a solution containing sugar and low doses of neonicotinoids. Honeybees and bumblebees were found to drink more from the solution containing pesticide, which suggests that the same behavior occurs in the wild.
“There’s a conundrum that they are attracted to the stuff that actually is having a negative impact on their motor function and their ability to collect food and forage,” she said.
Bees drugged, leading to behavioral changes
It is thought that the behavior is due to the similarities with nicotine, which is in fact produced by tobacco plants to protect itself from insects. Nicotine is toxic in large amounts, but acts like a drug in small doses.
”As soon as it gets into their blood they are getting a little buzz, as it were, and they are responding to that,” Wright said.
A separate piece of research carried out by Swedish scientists found that oilseed rape sown using seeds coated in neonicotinoids led to a reduction in wild bee density, solitary bee nesting and the growth of bumblebee colonies.
However neonicotinoid exposure did not greatly impact honeybee colonies, which may be because they have larger colonies that are better able to deal with damage. Scientists claim that evidence against the chemicals was mounting.
“At this point in time it is no longer credible to argue that agricultural use of neonicotinoids does not harm wild bees,” said David Goulson, a biologist at the University of Sussex, who did not work on either of the studies.