Beekeepers are struggling to learn why honeybee numbers have dropped in recent years.
Members of Congress, including three from Connecticut, have signed a letter urging the Environmental Protection Agency to better regulate a controversial class of pesticide called neonicotinoids.
"Neonicotinoids are insecticides that are systemic in plants," said Kimberly Stoner, associate scientist at the Connecticut Agricultural Experiment Station. Stoner researches how neonicotinoids move in squash plants. "They spread in the vascular system of the plant," she said. "One of the concerns is the extent to which they can spread to the pollen and nectar of the plant and be spread by the bees."
That worry is shared by beekeepers who are struggling to learn why honeybee numbers have dropped in recent years. Stoner said beekeepers in Connecticut lost about half their colonies each of the past two winters. She said these mass die-offs could have many causes. "They are exposed to pesticides," she said. "They are suffering from Varroa mites -- parasitic mites that have been a big problem for beekeepers since the 1980s -- and, in some places, they are short of floral resources."
Stoner said there is value in looking at the range of pesticide applications, particularly when it comes to home use. But she said they are safer than older pesticides like organophosates. "I think the calls to completely ban neonicotinoids should be tempered with looking at what the alternatives are that people would be using and whether those alternatives would be better for humans, the environment, and even for bees."
The U.S. Fish and Wildlife Service announced it plans to phase out use of neonicotinoids in all National Wildlife Refuges by 2016.
