That Stings! Study Shows Pesticides Could Reduce Bee Sperm
Published by the Natural Resources Defense Fund
Proving that we’re all still learning about “the birds and the bees,” new research released late last week revealed that the popular class of insecticides known as neonicotinoids or “neonics” reduced live honey bee sperm counts by up to 39%.
The study, which is titled “Neonicotinoid insecticides can serve as inadvertent insect contraceptives,” may conjure up images of “safe sex,” but everything about the results of this new study suggest that neonics may be exceptionally dangerous for bees.
A honey bee. Image by Maciej A. Czyzewski.
Bees—responsible for pollinating one third of our nation’s food crops—have it hard already. From 2015-2016, 44% of the managed honey bee colonies in the U.S. died. While those numbers are alarming, it’s even more disturbing that they’ve become commonplace, with professional beekeepers now in the habit keeping bee colony numbers up by splitting hives and importing queens from abroad. Wild bees—which are also critical pollinators—may be facing similarly tough times, but they’re numbers aren’t carefully tracked or managed.
It wasn’t always this way. While bee populations have been battered by loss of habitat, viral and fungal diseases, parasites, and climate change in the past, even with all that, annual colony losses before 2006 were less than half of what we see today. Although all of these problems have only gotten worse since then, this new norm of yearly massive bee die offs also coincided with the rapid growth of neonic pesticides in agriculture.
Industrial pesticide producers insist that this coincidence is just that—a coincidence. But this new study adds to an ever-growing body of evidence that suggests that the use of neonics produces real-world harms for bees. Importantly, the study finds “clear evidence” that neonics: “significantly reduce[d] the reproductive capacity of male honeybees; “reduced drone [i.e. male honey bee] lifespan;” and may even explain what’s causing the loss of queen bees and overall colony population declines.
Honey bee sperm under the microscope. A male bee exposed to small amounts of neonics may have up to 39% less of this. Image by Villamar L., Straub L., 2015.
In other words, the study finds what may be obvious: pesticides that the chemical producers and the EPA are well-aware can harm or kill bees do just that. What is less obvious, perhaps, is that these harms were observed even with tiny exposure amounts. In the study, male bees were exposed to food containing between 1.5 to 4.5 parts per billion of the two neonics tested (a bit less than a teaspoon in an Olympic-sized pool), which are exposure levels even smaller than what a typical bee might see in an average neonic-treated field.
As mentioned, this study adds to dozens already published demonstrating the clear harms that neonics inflict on bees. And while this study no doubt raises new questions, with the current bee crisis as severe as ever, regulators—first and foremost among them, the U.S. EPA—can and must act now to put an end to dangerous uses of neonics in order to protect bees and the people that eat the food they pollinate.
Read the full article at: https://www.nrdc.org/experts/daniel-raichel/stings-study-shows-pesticides-could-reduce-bee-sperm
