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| Beautiful bees having a feast! Notice the pollen baskets! |
You may have read or heard about the European Commission which will enact a 2 year ban on a class of pesticides, called neonicotinoids, starting December 1st. 2013. Bayer CropScience, the German company and Syngenta a Swiss biomedical company develop and produce many of the pesticides and fertilizers that are used in agriculture throughout the world today.
It is true that the total number of managed honeybee colonies has declined from 5 million in the 1940's to about 2.5 million today. (ARS) In the meantime the need for pollination services has increased tremendously. Therefore the colonies of bees have to travel (or be transported) over longer distance and probably more often to cover all the crops, adding potential stress.
In the 1980's, the US had seen a sharp decline in the health of the honey bee due mainly to pests and pathogens. Then 10 years later, the Varroa mite made its grand entrance via Asia, exacerbating the losses in the USA.
In 2006-07 the population of bee loss was: 32%, 2007-08: 36%, 2008-09: 29%, 2009-10: 34% and 2010-11: 30% , 2011-12 : 21.9% * It was overall a warmer winter in the US, but there is absolutely no scientific evidence or research between warmer weather and CCD (are.usda.gov). The Bee Informed Partnership (http://beeinformed.org), in collaboration with the Apiary Inspectors of America (AIA) and the United States Department of Agriculture (USDA), is releasing preliminary results for the seventh annual national survey of honey bee colony losses, 2012-13: 31.1%
Another potential problem, beside pests and pathogens is the increased use of systemic insecticides, which get into the pollen and nectar of plants. When properly used, the systemics are likely a blessing for bees, but comb sampling suggests that they are sometimes problematic. Judy Wu (2011) studied the effects of the toxic stew of miticides and systemic insecticides in commercial brood combs upon bee larval mortality and development, and adult longevity. Not surprisingly, the brood and bees suffered. Wu concluded, “Combined effects from honey bee exposure to pesticide residue in brood comb … may contribute to reduced honey bee colony health, as affected queens and worker bees are unable to meet the demand for brood production and resources needed to sustain large colony populations.”
In addition, both Judy Wu and other scientists have unpublished data which suggest that pesticide residues may make bees more susceptible to nosema, viruses, and Varroa. The above findings may help explain why colonies run in commercial pollination are so hard to keep alive! It is also true, that commercial beekeepers have seen their colonies go downhill after being exposed to the plethora of pesticides used in agriculture. A problem that cannot be ignore is that the residues remain in the combs, affecting the next generations of bees when beekeepers restock their dead-outs. Queen failures are also commonplace these days. (Scientific Beekeeping, R. Oliver)
Something interesting to note: In Europe regarding bee decline; data before 2008 can't be compared because each country did not used the same method of compilation. In France 2010-11 the bee loss was 17-22%, and it is also important to say that Gaucho a neonicotinoid (imidacloprid) has been ban on sunflowers since 1999.
However since 2008, the bee protection organization call COLOSS, compared surveys of honeybee losses in 2009 and 2010 in Europe with the rates of neonicotinoid application in the same areas, and in separate survey. They found no correlation. In countries experiencing bee decline, Varroa is feared even if necotinoids are absent! In France, it has been found that bee decline in mountainous areas are similar to those losses on agricultural land, although neonics are commonly used in the latter but not in the former, explains Dr. Cythia Scott-Dupree, Professor and Associate Chair of Environmental Biology MSC, PhD at the University of Guelph, Ontario, Canada. The upland areas of Switzerland, is another example where the neonicotinoids are not used and again the bee population is under significant pressure from the mites (Varroa).
On the other hand, where Varroa mites are not present like...in Australia, the bee population is thriving even when neonicotinoids are widespread in agriculture. Seed dressing products are being used in the field in Europe and in the US but in Australia, the seeds are usually mixed within an enclose space, perhaps decreasing the potential for bee and environment exposure, reports Raj Bhula, program manager--Australia Pesticides & Veterinary medicines Authority, CropLife Australia.
I have to mention that some pesticides are long-lived and persistent in the environment. For instance the pyrethroid pesticides are found in the wax of most hives that are place in agricultural fields. Neonicotinoids are generally found in stored pollen and nectar within the hive. A team of researchers at Pennsiylvania State University (J. Frazier, C. Mullin, M. Frazier, S. Ashcraft) "concluded that the 98 pesticides and metabolites detected in mixtures up to 214 ppm in bee pollen alone represented a remarkably high level for toxicants in the food of brood and adults. While exposure to many of these neurotoxicants elicits acute and sublethal reductions in honey bee fitness, the effects of these materials in combinations and their direct involvement in CCD remain to be determined."
It does not however diminish the concern that beekeepers are very troubled about pesticide exposures that don't kill the bees outright, but may affect their ability to thrive. The bee industry as a whole is very worried about several classes of insecticides, some fungicides and growth regulators that may impair the bee's immune system, causing queen and/or brood failure, compromising homing ability of foragers and/or disturbing communications within the hive...all of which seem to contribute to colony loss. Therefore the American beekeepers "strongly urge the EPA to re-evaluate these compounds long term using tier testing protocols that can give us the answers we need to mitigate losses."
In October 2012 in Virginia, the National Honey Bee Health Stakeholder Conference Steering Committee met to discuss the best way to help coordinate a federal response to address the new phenomenon called: Colony Collapse Disorder (CCD), described by the sudden and widespread disappearances of adult honey bees from beehives in the U.S.
The report on the National Stakeholders Conference on Bee Health is now available to the public to download. It contains a lot of pertinent information. I recommend reading it. (http://www.usda.gov/documents/ReportHoneyBeeHealth.pdf)
The conclusion of this report is as follows:
- Honey bee health decline is due to "complex" multiple factors/sterssors: viruses, varroa mites, poor nutrition, diseases, pesticides, lack of habitat and foraging, and cultural practices by beekeepers.
- Overall losses continue to be high and pose a serious threat to meeting pollination service demands for several commercial crops.
- European Union placed restrictions on 3 specific neonicotinoids insecticides: Clothianidin, Imidacloprid and Thiametoxan, which will take effect on December 1, 2013.
- The US will let science drive the outcome of their decisions. "It is important to get the science correct. There are non trivial costs to society if we get this wrong" said Jim Jones the agency's acting assistant administrator for chemical safety and pollution prevention.
- To keep in mind: Pesticide products provide a lot of benefits to farmers, and to consumers...for one, affordable food in the United States.
National Honey Bee Health Stakeholder Conference Steering Committee
USDA Office of Pest Management Policy (OPMP) David Epstein
Pennsylvania State University, Department of Entomology James L. Frazier
USDA National Institute of Food and Agriculture (NIFA) Mary Purcell-Miramontes
USDA Agricultural Research Service (ARS) Kevin Hackett
USDA Animal and Plant Health and Inspection Service (APHIS) Robyn Rose
USDA Natural Resources Conservation Service (NRCS) Terrell Erickson
U. S. Environmental Protection Agency (EPA) Office of Pesticide Programs (OPP) Thomas Moriarty
Thomas Steeger
In addition, approximately 175 individuals participated, including beekeepers, scientists from industry/academia/government, representatives of conservation groups, beekeeping supply manufacturers, commodity groups, pesticide manufacturers, and government representatives from the U.S., Canada, and Europe.
