After the mass poisoning of over 50,000 bumble bees last week in Wilsonville, Oregon and other incidents now being reported in neighboring Washington County, scientists are calling on local officials to ban the cosmetic use of insecticides on city- and county-owned lands. The mass poisoning is the largest event of its kind ever documented, with an estimated impact on more than 300 wild bumble bee colonies.
According to Oregon Department of Agriculture, the poisoning occurred after an insecticide was sprayed on linden trees to control aphids, which secrete a sticky residue while feeding, making them a nuisance to parked cars. The pesticide, dinotefuran (also known as Safari), belongs to a relatively new and controversial group of chemicals called neonicotinoids. Because neonicotinoids are long-lasting in plant tissues and can be found in flower nectar and pollen, and because they have been implicated in the global decline of honey bees, there have been growing concerns about their safety for pollinators.
"The cost of losing pollinators far outweighs any value of controlling aphids on ornamental plants," said Mace Vaughan, Pollinator Conservation Director at the Xerces Society for Invertebrate Conservation. "After the events of last week, and based on the overwhelming science demonstrating the harm that these products can cause, we are calling on city and county governments to immediately stop the damage."
The University of Minnesota's Dr. Marla Spivak, a leading global authority on bee health, echoed Vaughan's sentiment. "The Oregon bee poisoning is a clear warning. We have to stop pesticide use in cases where human health or food security is not at risk."
Spivak points out that neonicotinoids are now the most widely used insecticides in urban and agricultural areas. "They are long-lasting in soil and they readily move into water. If the Oregon event is an indication of what is happening more widely, we will begin to see catastrophic threats to food security and the pollination of wild plants."
In response to these concerns, several local governments are taking action to prevent further bee deaths. One of the most startling of these efforts was the City of Wilsonville's leadership in wrapping the insecticide-laden trees with netting last week to keep any more bees from dying. The City of Eugene had previously publicly stated that they are no longer using neonicotinoids on city properties. In May, Commissioners from Thurston County, Washington unsuccessfully petitioned their state department of agriculture (WDA) to restrict some uses of these chemicals in their county. It is unclear whether WDA is now reconsidering their earlier rejection of the Thurston County petition, which was initiated out of concerns for pollinators such as honey bees and bumble bees.
The Xerces Society applauds the actions on the part of Wilsonville and Eugene to protect bees, but says more needs to be done.
"It is time to take a stronger stance on pollinator protection. The European Union has put restrictions in place on several neonicotinoids, and Ontario, Canada has gone further and banned all pesticides for cosmetic use," said Scott Hoffman Black, Executive Director of the Xerces Society. "We need a similar response here."
Neonicotinoid insecticides, with active ingredients like imidacloprid, dinotefuran, thiamethoxam, and clothianidin, can be purchased in most hardware stores and nurseries under various trade names. As scientists like Vaughan and Spivak point out, most have no warning labels to alert consumers about the potential hazard to bees, butterflies and other beneficial insects.
To help prevent future bee poisonings, the Xerces Society is calling for changes to both regulations and consumer behavior.
"In terms of what we would like to see, legislators, regulators, and municipal leaders across the country should ban the use of neonicotinoids and other insecticides for cosmetic purposes," said Black. "At a broader level, it is time for the Environmental Protection Agency to re-assess the ecological safety of neonicotinoids and immediately suspend any product registrations that were made with incomplete data."
Jennifer Hopwood, the lead author of the Xerces Society's report on the risks of neonicotinoids to bees ("Are Neonicotinoids Killing Bees") says that there are also steps that individuals can take to avoid harming pollinators, like checking to see if they have neonicotinoid products in their garage or garden shed. "Consumers should know that they can return pesticides to the store where they purchased them for safe disposal. Beyond that, when buying garden plants, people should ask the store if insecticides have been used on them. If staff can't tell you, I would shop somewhere else."
The Xerces Society will be following up with mayors, city councils and county commissions across the US with formal letters asking them to take action.
The Xerces Society recommendations include:
For municipalities
- Municipalities should stop using all neonicotinoid insecticides on city- and county-owned property, including schools, parks and gardens.
- City and county governments should require that warnings be posted alongside displays of these chemicals at hardware stores and nurseries.
- Legislators, regulators, and municipal leaders across the country should ban the use of neonicotinoids and other insecticides for cosmetic purposes on ornamental and landscape plants, like the ban now in force in Ontario, Canada
For homeowners
- Do not buy products that contain neonicotinoids. A list of products can be found at www.xerces.org/pesticides
- Check to see if you have these products in your garage or garden shed. If so, do not use them. Make sure you dispose of them properly or take them back to the store where you bought them.
- When buying plants for your yard, ask if neonicotinoids have been used on them. If staff cannot tell you, shop somewhere else.
For nursery and hardware stores
- Stores should proactively take action by pulling these toxic and poorly labeled products from their shelves.
- At a minimum, display materials should be placed at point of sale so that consumers know that these products kill bees and other beneficial insects, and that they can cause plants to produce toxic nectar and pollen months after treatment.
- Nurseries should list plants that have been treated with these chemicals.
For the federal government
- The EPA should work with pesticide companies to add clear warnings to homeowner and ornamental neonicotinoid insecticides that are toxic to bees and other pollinators.
For insecticide companies
- Companies that make homeowner pesticide products that contain neonicotinoids should add clear language to product labels highlighting that these products are highly toxic to bees and other pollinators, and that treatment to plants may result in nectar and pollen that are contaminated with the insecticide and may kill bees and other pollinators.
