The systemic pesticides known as neonicotinoids have contributed CCD, scientific evidence shows.
As a growing body of research points to a link between colony collapse disorder and the class of pesticides known as neonicotinoids, a backyard gardener in Virginia has taken to the Internet in a grassroots effort to have Bayer’s neonicotinoid pesticides taken off the market.
Susan Mariner, who grew up working the garden with her father and grandmother, says the value of pollinators was impressed upon her from an early age.
“My grandmother taught me that bees are ‘our partners in the garden,’” she remembers.
Today, Mariner has her own suburban backyard garden, where she and her children grow edible crops, as well as what she calls a “Honey bee haven”: a section planted with colorful wildflowers and other plants that attract native pollinators. In the past several years, she says, her favorite winged visitors have made fewer appearances in the garden.
“I started watching bees as a young child in my father’s and my grandmother’s gardens and apple trees, which were awash in Honey bees when in bloom,” she says. “These days, when my children and I spend all day outside surrounded by thousands of blooms in our garden, we are thrilled to see a single Honey bee visit.”
Mariner says the decrease in pollinators has changed the way she and her neighbors garden. “Because there are so few pollinators, in recent years we have been forced to hand-pollinate many of our plants, something which would have been unthinkable to my grandmother. Many of my gardening neighbors have stopped growing plants that require insect pollination altogether.”
Increasingly, however, researchers are finding that the activities of Mariner’s other neighbors—those who are, in her words, “unwittingly coating their properties in neonicotinoids to achieve a picture-perfect lawn”—may be contributing to a dearth of pollinators.
Synthetic forms of nicotine, neonicotinoids act on insects’ nervous systems by binding to nerve-cell receptors and disrupting nerves’ abilities to send normal signals. Eventually, these repeated misfires cause the nervous system to fail and the insect to die. Imidacloprid is the most common systematic pesticide in the neonicotinoid class; it appears in a host of insecticide products formulated for veterinary use (as flea treatments), agricultural use (as both soil and foliar treatments and seed coatings) and landscaping (including product lines, such as Bayer Advanced, formulated for consumer use).
In January 2012, an Italian research team published a paper in the journal Environmental Science & Technology reporting on increased mortality and neonicotinoid neurotoxicity among bees in hives located near fields where pesticide-coated seeds were sown. Whereas much of the research on CCD and pesticides has focused on indirect exposure (through pollen or nectar, for example), the Italian scientists hypothesized that bees were directly exposed to neonicotinoids via particulate matter released from seed drills. Less than three months later, a paper in the journal Science reported on an 85-percent reduction in production of new queens in neonicotinoid-treated bumblebee hives. After reading about the study, Mariner felt compelled to take action.
Mariner used Change.org, a free petition-hosting website that harnesses social media in the name of activism, to launch a petition calling for the Environmental Protection Agency to ban Bayer’s neonicotinoid-based products. With each signature, Change.org sends an email to the person or persons targeted by the petition—in this case, three key EPA administrators. Mariner’s petition garnered a massive response, boasting over 138,000 signatures as of April 26, 2012.
Mariner says she’s thrilled with the reception her petition has received. “I’ve been extremely encouraged to see that once people learn that one-third of our food is pollinated by bees and that bees are in crisis, they are anxious to help and automatically begin spreading the word to others.”
Within days of Mariner’s petition going live, a team from the Harvard School of Public Health reported that they’d gathered still more evidence of an imidacloprid-CCD link. Over 23 weeks beginning in summer 2010, the researchers monitored bees in four different yards in Worcester County, Mass. Each yard had four bee hives treated with varying levels of imidacloprid, as well as one control bee hive. After 12 weeks of dosing, all the bees were alive, but after 23 weeks, 15 of the 16 treated bee hives had died off, with the highest-dose bee hives perishing first. The Harvard study will appear in June’s Bulletin of Insectology.
“The Harvard study is further evidence that neonicotinoids are a key factor in the decimation of our nation’s bee population,” Mariner says. “There is now sufficient evidence of the link between neonicotinoids and CCD that the EPA needs to immediately suspend registration of neonicotinoids. With our bee population in a nationwide freefall, the EPA’s plan to act on neonicotinoids in 2013 is not acceptable. Bees, and the many plants that depend on them, need protection now.”
As Mariner moves toward the goal of 150,000 petition signees, she says she’s busy writing about bees’ plight for several blogs and websites, taking interviews with media outlets, and giving presentations on CCD. She’s also encouraging fellow pollinator-lovers to contact their congressional representatives.
“In addition to keeping pressure on the EPA, it’s critical that we begin pressuring Congress to use its oversight authority to force the EPA to act now,” she says.