Neonicotinoids and CCD

Beekeepers have long suspected the role of the neonicotinoid insecticides in the great upsurge of honey bee colony die-offs that have continued since 2006. Named Colony Collapse Disorder, the loss of honey bee colonies has persisted for eight years in spite of efforts by researchers to identify a cause and by beekeepers to replenish their hive numbers. According to the Bee Informed Partnership’s recently released report, http://beeinformed.org/2014/05/colony-loss-2013-2014/, annual losses have averaged an unsustainable level of nearly 30 percent. A relatively small-scale study by Harvard School of Public Health, http://www.bulletinofinsectology.org/pdfarticles/vol67-2014-125-130lu.pdf, reveals interesting findings. Honey bee colonies exposed to either of two low levels of neonicotinoid insecticides, imidacloprid or clothianidin, abandoned their hives during the winter, defining symptoms of Colony Collapse Disorder. This report contrasts somewhat from the results of a previous study on the effect of pesticides that lead to susceptibility to the honey bee gut pathogen, Nosema ceranae. The larger study, reported in PLOS ONE, http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0070182#authcontrib, finds large numbers and high levels of pesticides in honey bee hives. The researchers found 35 different pesticides in sampled honey bee pollen and high levels of fungicides.

Until recently, fungicides, chemicals designed to fight fungal infections, were considered safe for honey bees. Recent studies are finding fungicides to have an adverse effect on honey bee health, often making insecticides and miticides more toxic to bees. In the PLOS ONE study, fungicides were found to lead to Nosema infection. Needless to say, the search for the cause of Colony Collapse Disorder has revealed the complexity of the problem. There are many factors contributing to honey bee health, including nutrition, parasitic mites, pest insects, viral, fungal, and bacterial diseases, and environmental chemicals. Studies are finding insecticides, miticides, fungicides, and herbicides in the bee hives. Combinations of chemicals and breakdown products of chemicals are often highly toxic to bees. Peace Bee Farm has participated in a number of the studies. Today, catalpa trees secrete nectar from the flowers and nectaries on the leaves.

--Richard

Chemicals in the Environment

The world that you and me and the honey bees live in is being sprayed, coated, and drenched with chemicals. Agricultural fields, lawns, and golf courses are treated with chemical fertilizers, herbicides, and pesticides to produce larger crops, and greener, weed-free grass. The visible effects of this level of chemical use can be measured in more food crop yield per acre of farmland, less fuel consumed tilling the soil, crops available for conversion into alcohol for fuel, and greener lawns and golf courses. Some of the less visible effects of today’s chemical use include weeds becoming resistant to herbicides; pests becoming resistant to insecticides, miticides, and other pesticides; water quality affected by chemical run-offs; soil damaged by persistent chemicals; increased monoculture farming; the loss of pollinator forage and habitat; and the compromising of honey bee immune systems.

While the recent report of one scientific study of honey bee health pointed to a lethal combination of Nosema disease and Invertebrate Iridescent Virus, beekeepers who have been following the CCD investigation are asking questions about the findings. Particularly troubling to some is the lack of mention of certain insecticides that have been suspected of damaging the honey bees’ immune systems. Many beekeepers in Europe and North America feel that the neonicotinoids, like Imidacloprid, have not been proven to be safe for honey bees. To add to the lack of trust among beekeepers, some are questioning the conflict of interest between researchers and chemical companies. For example, see http://money.cnn.com/2010/10/08/news/honey_bees_ny_times.fortune/index.htm. Regardless, any scientific investigation must be able to stand up to scrutiny. Confidence in tests is built by repeating the tests and increasing the number of samples taken. The association between Nosema disease and IIV Virus in collapsing honey bee colonies needs further study. The connection between sub-lethal exposure levels of Imidacloprid and honey bees’ immune systems certainly needs independent study. Today’s photo: An aerial applicator sprays insecticides to kill soybean loopers. Insecticides and fungicides are questioned as having weakened honey bees.

--Richard

Chemicals in the Environment

Researchers looking for the causes of honey bee Colony Collapse Disorder have found dozens of chemical agents in the beeswax honeycomb of affected bee hives. Beeswax readily absorbs and holds chemicals. The chemicals found include miticides used by the beekeepers to combat the parasitic mites that have devastated honey bee populations since they were discovered in the United States in the 1980s. The mites changed beekeeping from a craft in which chemicals were rarely used to one in which chemicals were used routinely. As could be expected, the chemicals found in the greatest concentrations are the common miticides, Fluvalinate and Coumaphos, both considered to be “harsh” pesticides. Other chemicals found in honeycomb included dozens of insecticides and pesticides. One insecticide being found in honeycomb is Imidacloprid, suspected by many beekeepers as affecting honey bee health. Imidacloprid, a member of a class of insecticides designed to be more environmentally safe than earlier products is often used to kill gnawing and chewing insects in lawns and crops. These insecticides are widely used in crop seed treatments, flea collars for pets, and home termite controls. In crops, Imidacloprid has a systemic action; it is carried through the vascular system of the plant, poisoning insects that chew the foliage. It is also brought back to the bee hive by bees foraging for nectar and pollen. Researchers are questioning the sub-lethal effects of this insecticide on honey bees.

There is considerable dependence today upon chemical fertilizers, herbicides, and pesticides for producing crops, growing lawns, and controlling termites. Genetically modified crops use herbicides to control weed growth, resulting in high-yield crop production at lower cost from reduced soil tillage. Concerned beekeepers, like us at Peace Bee Farm, are moving toward reduced chemical usage, avoiding “harsh” miticides in favor of “softer” agents, like those based on essential oils. In today’s photo, an agricultural applicator passes low over one of my bee yards then negotiates power lines and a passing chemical tanker to spray an adjacent field.
--Richard

Industrial Agriculure

Aerial application of seeds, chemical fertilizers, herbicides, and pesticides are some of the key elements of modern industrial agriculture. These large-scale farms plant fields of monoculture crops on precision-leveled ground using heavy equipment and little manpower. Many fields are irrigated, and herbicide use has largely replaced cultivation for weed control. Aircraft are employed to distribute seeds or chemicals when time constraints or soil conditions make application from the ground impractical. For example tractors can’t be driven in flooded rice fields and soybeans planted in narrow rows grow so closely that they would be damaged if cultivated by tractor.

Aerial applicators as well as farmers using ground-based spray equipment pay particular attention to honey bees in the area of their spraying. If they are distributing insecticides, they spray early in the morning or late in the evening when the honey bees are not actively foraging. They are careful not to spray directly onto the hives and to avoid drifting of the spray. However, it is not always obvious that bees are present in a particular field, since they regularly fly two to three miles from the hive to forage. Large-scale die-offs of honey bees from chemical poisoning do occur at times. Insecticides used in boll weevil eradication programs were deadly to honey bees in the area. Beekeepers are still unsure of the safety of some systemic insecticides, like imidacloprid, in common use today. Modern agriculture practiced on an industrial scale is efficient in the production of large quantities of food and fiber. It does impact the honey bees and native pollinators, though. Much of the impact results from the large size of the monoculture fields with no margin for pollinator habitat. Beekeepers and farmers understand that they share in the benefit of healthy bees. Today’s photo shows a high-performance aerial applicator passing low over one of our bee yards in the still air shortly after dawn to spray an adjacent field.
--Richard

Evening Primrose in Bloom

The evening primrose is a nighttime blooming wildflower. While I have observed it being worked at dawn by honey bees foraging for pollen, it primarily attracts other pollinators. I have seen flies, moths, butterflies, and solitary bees working evening primrose early in the morning. Luna moths, the size of small birds, work the flowers at night. Click on the picture to see a blue orchard bee foraging for pollen in an evening primrose blossom. The fast flying and gentle blue orchard bee strikes the flower hard and then scrubs its body around inside of the blossom. Its active movement inside the flower makes the blue orchard bee an effective pollinator. The native blue orchard bee carries its load of pollen on hairs on the lower side of the bee’s abdomen.

The current research program that the USDA is funding to study bee health involves both honey bees and other pollinators. Bees that are not honey bees, called non-apis bees, are being established in managed arrangements at each of the seven bee yard locations in the nation-wide study. The purpose of this study of these non-apis bees is to determine if there are cross infections between the species. Bumble bees are being sampled to check for stress and, hopefully, increase efficiency of their use as pollinators. The investigators are also studying the effects of the neonicitinoid pesticides, like Imidacloprid, on the non-apis bees. They are looking into the sub-lethal effects of these pesticides and any effects caused by their residues. The non-apis bees, like the blue orchard bee, serve an important role in helping to pollinate flowering plants. They help the honey bee complete the pollination required to produce fruit and seeds for wildlife and humans.
--Richard

Bee Health Studies

Honey bees have been declining in numbers for the past three years. This year’s loss is slightly less than the previous two year’s losses of nearly a third of the nation’s bees each year. Yes, it’s been three years since the honey bees were first reported as leaving their hives in what is called Colony Collapse Disorder; and we still don’t have a known cause. The solution of the mystery has proven difficult, as there are numerous complex factors affecting honey bee health. The good news is that Colony Collapse Disorder brought enough attention that bee health is now receiving some long needed scrutiny. In the first year of a four year study headed by the University of Georgia, researchers have established seven apiaries across the country to study the genetics of the Varroa mite, honey bee viruses, Nosema parasites, miticides, and the effects of farm pesticides. They are also trying to encourage local production of queen bees to counter the effect of a lack of honey bee genetic diversity. The Environmental Protection Agency and the USDA have narrowed the potential causes of honey bee disease to six: new and re-emerging pathogens, pesticides, habitat loss, pests that infest bee hives, commercial bee management practices, and nutritional stress. Imidacloprid, a systemic insecticide in widespread use, has been suspected by beekeepers as being a possible cause of Colony Collapse Disorder. Its manufacturers claimed it was safe for bees. It may now be independently tested.

While examining my bee yard at the Memphis Botanic Garden, I walked over to the farmers market and ran into Marge and Joann. They come out each week, buy our honey, shop for fresh produce, and visit. They always ask about the bees. Hopefully, we will be able to start reporting some progress resulting from the studies in bee health. The University of Tennessee has placed extensive honey bee health information on the USDA web site eXtension.org. Follow the path: Resource Areas-Farm-Bee Health.
--Richard