The Buzz on Colony Collapse
An insidious new class of pesticides threatens our food supply’s most important pollinators.
With a wag of its tail, a honeybee can tell its siblings where to find a flower miles away. These sophisticated creatures communicate via vibration and pheromone. Not only do bees transform nectar into honey; they also pollinate at least one-third of our food supply. Without these winged workers, many of our favorite fruits and vegetables would never ripen on the vine or branch.
But there’s trouble in the hive.
Honeybees began vanishing in the autumn of 2006, leaving behind empty hives and few clues. Beekeepers around the globe reported staggering losses: 30 percent to 90 percent of their bees. Historically, beehives have failed during severe winters, or disease outbreaks, but never on such a scale. This mysterious epidemic, called colony collapse disorder, is now in its seventh year.
Despite the severity of the problem, scientists have been reluctant to pinpoint a cause. In fact, the causes are legion. For starters, monocrops, which have replaced small, diverse family farms nationwide, offer a stingy selection of pollen. Miles and miles of just soybeans, or corn, result in malnourished bees.
Migratory pollination—trucking millions of hives across the country and back again to pollinate vast industrial farms—puts additional stress on bee populations and allows bees from distant regions to mingle and swap diseases and parasites.
But the killing blow may be a new class of pesticides. Neonicotinoids, chemicals designed to mimic plant-based nicotine, are deployed against pests such as aphids, beetles, and fleas. Released in the mid-1990s, they now rank among the most widely used insecticides in the world. Biologists hailed them as a safer alternative to existing pesticides that pose human health risks. But new evidence suggests that neonicotinoids persist in the environment and even trace doses can devastate bees.
Often applied as seed coatings, neonicotinoids are systemic: as a treated seed grows, the toxin migrates to every part of the plant, including the pollen and nectar that bees collect. In 2012, the U.S. Department of Agriculture’s lead bee researcher, Jeff Pettis, published a study revealing that exposure to imidacloprid, a popular neonicotinoid, greatly increased bees’ vulnerability to infection by nosema, a fungal parasite. A recent study by Harvard biologist Chensheng Lu further implicated imidacloprid in colony collapse disorder. Lu surmised that commercial beekeepers might be accidentally dosing their hives with the toxin when they supplement their bees’ natural food—honey—with high-fructose corn syrup. Since corn farmers began applying imidacloprid to fields in 2004, corn syrup has contained traces of the pesticide. Sure enough, 93 percent of the hives that Lu fed with imidacloprid-laced syrup collapsed.
The U.S. Environmental Protection Agency has been slow to scrutinize neonicotinoids. After repeated petitions from beekeepers and pesticide watchdogs the agency agreed to a comprehensive review of the chemicals, but it won’t be complete until 2018.
Meanwhile, Europe has taken action. This April, despite substantial lobbying by chemical manufacturers, members of the European Union voted to restrict the use of three neonicotinoids. Imidacloprid, clothianidin, and thiamethoxam will be banned for use on flowering crops throughout Europe for a two-year trial.
Chemical companies insist that this measure will not help the beleaguered bees; beekeepers hail it as an essential first step.
This June, 50,000 bees were discovered dead and dying outside a Wilsonville, Oregon, shopping center. Bee experts learned that blooming linden trees in the parking lot had been sprayed with a pesticide containing Dinotefuran, a common neonicotinoid. Following this and similar reports of bee poisonings, the Oregon Department of Agriculture enacted a temporary ban on the use of Dinotefuran.
What You Can Do
If You Have a Minute…
Speak for the bees. Go to causes.com/savebees and sign a petition urging the Environmental Protection Agency to ban the use of neonicotinoidal pesticides.
If You Have an Hour…
Make your garden bee-friendly. Add native plants and wildflowers, which are better sources of nectar and pollen than showy, hybridized blooms. Cultivate species that bloom at different times of year, so pollinators have a stable food source. Don’t use pesticides.
If You Have a Month…
Become a backyard beekeeper. Start-up costs for two hives range from $500 to $800, and harvests start at 50 pounds of honey each year. “Keeping bees will change the way you see the world,” says USDA apiary specialist Danielle Downey. “You see plants and flowers differently; you notice weather patterns on behalf of your bees.”
If You Have $100…
For the cost of a nice dinner out, you can buy your family (and gift your friends!) local, organic honey for a year. Support neighborhood beekeepers and their hive dwellers while avoiding the possibility of pesticide-laced, or adulterated commercial honey.