The ongoing mystery of Colony Collapse Disorder (CCD), since first being reported in 2006, continues to affect honeybees and farm crops globally and here in Utah. While overwinter bee loss is normal, the overall health of bees both wild and domesticated, on the decline since the 1940s, has only worsened with the introduction of pests and pathogens in the 1990s. Last April Forbes magazine reported that a third of honeybees in the United States were lost over winter.
Spain suffered an 80% loss. In Utah, the most recent numbers from the Department of Agriculture and Food show a 40% loss. Yet some places, Canada and Australia, are still untouched by this sweep of death.
The cause of this die-off remains unknown, though hypotheses abound. Cell phone signals have been blamed—a conclusion based on a small study in Germany and widely dismissed by agriculture experts and scientists. Other potential culprits include environmental and management stressors like pathogens, parasites, and scarcity of food or poor nutrition due to overcrowding—often a problem where commercial hives congregate for commercial crop pollination.
Now, a new culprit is garnering international attention, neonicotinoids (neo-nicotine-oid), a powerful neuro-toxin that attacks the central nervous system of insects,. The irony is that this class of pesticide was developed by Shell and Bayer in the mid-1990s as a less-toxic alternative designed specifically to protect pollinators. The key principle that supposedly makes neonicotinoids “safe” is their method of application. Often used as a seed treatment for crops like corn, this point-specific application avoids broadcast spraying of mature plants, thus allowing the pesticide to target the pest only.
Still, operator error can do serious damage. As shoppers at an Oregon Target near Portland learned last summer, the potential for neonicotinoids to kill non-targeted creatures is very real. When 25,000 bumblebees, ladybugs and other pollinators fell dead in the shopping center’s parking lot, the single largest recorded pollinator die-off in the country, investigations revealed pesticide poisoning. Landscapers had treated European linden trees in full bloom with a neonicotinoid, almost instantly killing the tens of thousands of pollinators that swarmed the trees’ nectar-laden flowers.
Although nothing of similar magnitude has occurred in Utah, cases of neonicotinoid-related pollinator deaths have occurred here, reports Clint Burfitt, Program Manager for the Utah Department of Agriculture and Food Apiary Inspection Program. And, as with the case in Oregon, most are due to careless pesticide application. “Pesticides can play role in bee die-off, but they are usually local or isolated incidents,” says Clint Burfitt. “Generally, if I see a pesticide-related incident, it’s in a very specific situation—say, a crop dust plane flies over, dropping pesticides and kills beehives on the ground.”
Such incidents may be the clearest links between pollinator deaths and neonicotinoids, but they are almost certainly not the only events.
Persists in plants and soil
Neonicotinoids are systemic—they move throughout the plant. Applied to the seeds, trunk, leaves or even the soil surrounding plants, the pesticide travels to other parts including pollen, nectar and even into surrounding soil and groundwater.
“Any insect feeding on pollen or nectar could be exposed to the systemic insecticide,” writes Richard S. Cowles of the Connecticut Agricultural Experiment Station. Since neonicotinoids used in arboriculture have proved particularly toxic to bees, Cowles recommends not treating trees or plants that attract pollinators. He says even low exposure “can cause maladaptive and lethal behaviors” associated with Colony Collapse Disorder (CCD) such as impaired navigation and inability to gather food, ward off diseases or reproduce.
A study published this May in the Bulletin of Insectology, authored by Chensheng Lu, associate professor of environmental exposure biology at Harvard School of Public Health, concludes that CCD is related specifically to neonicotinoids. After comparing overwinter hive loss, the study showed a loss of half the neonicotinoid-treated colonies versus one out of six non-treated hives.
At the University of Sussex, Dr. David Goulson, Ph.D, is studying just how long neonicotinoids persist in plants and soil. According to the manufacturer’s own data, says Goulson, one form (clothianidin) can remain in soil for almost 19 years. Bioaccumulation of neonicotinoids increases toxicity levels. Because they are water soluble, their persistent presence can contaminate ground and surface water, extending their impact far beyond their intended target.
Following the Target die-off incident, the city of Eugene, Oregon unanimously passed a resolution banning the use of neonicotinoids on city property—strengthening the city’s already strong pest management policy that includes no-pesticides zones around many of the city’s parks and recreation areas.
Oregon’s hippies aren’t the only ones questioning the benefit of neonicotinoids. Last year the European Commission instated a continent-wide, two-year ban on neonicotinoids. In the United States, following a petition from the Center for Food Safety, the U.S. Fish and Wildlife Service announced plans to phase use neonicotinoid use in wildlife refuges in the Pacific Northwest by 2016.
Here in Salt Lake, we don’t need to be concerned yet about the potential for massive pesticide-related pollinator deaths. While there is no specific ban on using such chemicals, Dax Reid, Natural Lands Supervisor for Salt Lake’s Parks and Public Lands Program, says the city’s Open Space program does not currently use insecticides containing neonicotinoids, and none of the herbicides used list neonicotinoids as an active ingredient.
Responsibility to protect pollinators does not rest entirely on city officials. Home gardeners can just as easily obtain and use pesticides and herbicides with neonicotinoids. Various versions of the compound appear in products as seemingly innocuous as Bayer’s Rose & Flower Care or Scott’s Tree & Shrub Insect Control Ready-to-spray (for a more complete list of home gardening products that contain neonicotinoids go to www.beyondpesticides.org/ pollinators/documents/pesticide_list_final.pdf)
One piece of evidence that continues to keep neonicotinoids off the hook as the lone contributor to Colony Collapse Disorder is the fact that some countries, like Australia, are not seeing colony collapse but do use neonicotinoids. Australia also does not have Varroa mites. Some believe this alone shows that CCD is a combination of factors including disease, environmental issues and pesticides.
Varroa mites, an external parasite that attacks the adults and brood of honeybees, were originally found only in Asia. Native hosts were largely unthreatened by the pest, but when the mite spread to European honeybees in the 1960s, the new hosts proved less resilient. Weakened by deformities caused by the mite, European honeybees began to die.
Commercial beekeeping has been a significant factor in the rapid spread of Varroa mites and other problems associated with incidents of CCD. As hives move across the United States, in constant pursuit of the next crop ready for pollination, these colonies, despite regular treatment with antibiotics, continue to spread disease not just to each other but to local domesticated and native wild bee populations.
Utah’s Grand County has an extremely low rate of CCD and is actively working to maintain that record. The town of Castle Valley has placed an outright ban on commercial beekeepers in the area, an attempt to limit exposure to pests and pathogens circulated by traveling hives as well as to avoid the problematic factor of resource competition. In another tactical move, Grand County is looking at limiting the number of bees per lot, which could prevent large commercial keepers from moving in hives.
But even with regulations, inspections and careful planning, here in Utah and along the Wasatch Front, CCD outbreaks occur. For hobby beekeepers, being aware of local disease outbreaks, having the ability to recognize a problem and knowing what to do are essential to protecting colony health and hopefully preventing a collapse.
“We try to teach beekeepers best practices,” says Clint Burfitt, Apiary Inspection Program Manager, in a government program that has required Utahns to register their hives since 1879. When the apiary program recently found four cases of American Foulbrood, a highly contagious bacterial disease spread through spore-contaminated nectar, honey and pollen stores, they notified all registered beekeepers within a four-mile radius. Such alerts are just one of the services the program provides.
In recent years, Burfitt has witnessed a rise in the popularity of backyard beekeeping. Utah, says Burfitt, has 2,000 registered beekeepers. Salt Lake alone has nearly 50 registered beekeepers per square mile. While disease prevention is important to reducing cases of CCD locally, such a high concentration of hives will make a certain amount of hive loss inevitable. “We have limited foraging resources in an urban environment,” Burfitt explains. “As the city grows, we continue to pave over habitat essential for all pollinators, native bees and European honeybees.”
For now, some of the power to save bees rests in our hands. Choosing not to use pesticides, specifically neonicotinoids, in our gardens is a start. Planting pollinator-friendly gardens is additionally important. Flowering plants provide bees with food.
“Instead of putting another hive in the city, plant a pollinator garden,” encourages Utah’s apiary program inspector Clint Burfitt. “Because at the end of the day, it takes a village to raise a bee.”
Make a bee-friendly garden
Don’t be fooled by pretty labels.
These and other products, commonly available at Home Depot and other gardening centers, contain neonicotinoids and are bad for bees:
Monterey Concentrated Once-a-year insect control
Ortho Rose and Flower insect and disease control concentrate
Ortho tree and shrub fruit tree spray
For a full list of products to avoid:
2) Plant flowers that bees appreciate. Not all flowers are equal in the eyes of a bee. Tulips, marigolds and petunias may beautify a yard but, according to USDA research entomologist and Utah State University (Logan) adjunct professor James Cane, “these and other garden flowers have, through years of artificial breeding and selection, lost whatever attraction they may have had for bees.” Here is Cane’s list of suggested plants for a pollinator garden. Plants with a * are native to Utah:
yarrow*, monkshood (aconitum), hyssop*, carpet bugle, ornamental onions, hollyhock, serviceberry*, false indigo, dill, columbine*, manzanita, prickly poppy, sea thrift, aster*, desert marigold*, barberry, borage, mustard, annual coreopsis, American bellflower (campanula)*, redbud, mountain mahogany*, flowering quince, rabbit brush*, watermelon, clarkia*, cleome, cosmos, hawthorn, squash, prairie clover, carrot, queen Anne’s lace, larkspur*, ice plant, foxglove, coneflower (Echinacea), sea holly, California Poppy, fennel, strawberry, beeblossom, blue gentian*, sunflower, heliotrope, rose of sharon, sweet pea, lavendar, gayfeather, flax*, mint, mountain bluebells*, beebalm, basil, penstemon*, Russian sage, desert pincushion*, elderberry, thyme, valerian, zinnia, Indian blanket (Gallardia)*, blackeyed Susan (Rudbeckia)*
3) According to Laurence Packer, melittologist (that is, someone who studies wild bees) and author of Keeping the Bees: Why All Bees Are at Risk and What We Can Do to Save Them (2010: Harper Collins), there are almost 20,000 known species of bees—and fewer than 10 of those species are honey bees. Much like the European honey bee, these wild species are great pollinators. They, too, are facing a significant decline in numbers due to resource competition with honey bees and loss of habitat.
When planning a pollinator garden think of these wild bees as well, 90% of which do not live in a hive but rather in burrows in the ground, in hollow or pithy stems or in abandoned insect tunnels in wood. With this in mind, plant raspberry bushes—the stalks provide the perfect home for many of these bees. Don’t lay a cloth barrier over your garden, which inhibits burrowing bees from making their home. In fact, you might even want to leave a bare patch of soil undisturbed for ground-nesting bees to do their thing.