   The Honey Bee’s Plight - August 28, 2013 Jeff Schalau, Agent, Agriculture & Natural Resources University of Arizona Cooperative Extension, Yavapai County Most domestic honey bees kept by beekeepers are European in origin. These bees have been in the New World since the early 1600’s when European settlers brought honey bees with them, thus introducing this species to North America. Prior to that time, native plants and crops grown by Native Americans were pollinated solely by native bees. Economically, the value of the honey bee to United States agriculture has been estimated at $14 billion per year. Domestic honey bees pollinate over one hundred different fruit and vegetable crops in the U.S., including oranges, apples, and blueberries, as well as almond trees and animal food crops like clover. Each year, California’s almond orchards require 1.6 million hives to pollinate them. Bees are required for almond pollination and the annual crop of almonds is worth two billion dollars. As some readers may be painfully aware, African honey bees were crossed with European honey bees and introduced to southeast Brazil in 1957. These bees escaped captivity and have migrated northward. They reached southern Arizona in 1993 and Yavapai County Cooperative Extension has been receiving calls about them since 1998. These bees are often captured by beekeepers and the Africanized queen bees are replaced with calmer European queens. The “requeened” colonies are then used for pollination of crops and honey production. Honey bees have been slowly declining in the U.S. since 1952. This decline became more pronounced in October 2006 when Colony Collapse Disorder (CCD) was first documented in the U.S. In CCD affected hives, the adult bees abandon the hive, leaving behind the queen bee, brood and food stores. Since then, research has focused on identifying the cause(s) of CCD. Researchers currently believe CCD is caused by a combination of factors which may include a fungal parasite (Nosema ceranae) which lives in the bee’s gut and parasitism by Varroa mites: small parasitic arthropods that suck the blood of honey bees thereby weakening them. Tracheal mites are also a threat and these parasites interrupt the bee’s breathing apparatus. Viruses are also being examined for their role in CCD: the primary one under investigation is called Israel Acute Paralysis Virus (IAPV) which is vectored by Varroa mites. It is also interesting to note that native bees are also declining in numbers. The picture is not very clear at this point as scientists also suspect environmental factors, widespread use of pesticides, nutritional deficiencies, and bee hive management practices could be contributing to CCD. We have also greatly reduced bee food supplies by planting large agricultural monocultures and controlling weedy species – many of which produce nectar and pollen that benefit native and domestic bee populations. Intensive production practices and hauling colonies from place to place further stress these bees and could also be a contributing factor to CCD. When viewed individually, suspected causes of CCD can be addressed. Monitoring and purposeful application of miticides can be used to manage Varroa mites. Improved Varroa mite management could also lead to better virus management. A group of pesticides called neonicotinoids are also being carefully scrutinized. One of these is the active ingredient imidicloprid which has replaced the once widely used chlorpyrifos: an organophosphate insecticide (which was also toxic to bees). Neonicotinoids remain toxic to bees longer than other pesticides. They are regularly injected or applied as a soil drench which allows them to be taken up by the plant. Foraging bees may collect pollen from treated plants and store it in their hive for future use. In addition, some adjuvants (substances added to improve pesticide performance) are thought to be harmful to bees and are being investigated. The causes of CCD are still unclear and lots of research is being conducted to clarify the causes and seek solutions. While the role of pesticides is still being investigated, agricultural producers and homeowners can minimize and/or time pesticide applications to minimize risk to honey bees. Here are some best management practices that will help protect all bees. If you must apply an insecticide: choose low toxicity/low residue pesticides such as soaps or oils; apply pesticides in the early morning or evening when bees are less active; minimize pesticide drift (air movement or volatilization causing movement off target); avoid spraying blooming plants whenever possible; avoid the use of neonicotinoids such as imidicloprid. Finally, we can all plant pollen and nectar producing flower to feed native and domesticated bees. Additional honey bee resources are included below. Follow the Backyard Gardener on Twitter – use the link on the BYG website. If you have other gardening questions, call the Master Gardener help line in the Camp Verde office at 928-554-8999 Ext. 3 or e-mail us at cottonwoodmg@yahoo.com and be sure to include your name, address and phone number. Find past Backyard Gardener columns or provide feedback at the Backyard Gardener web site: http://cals.arizona.edu/yavapai/anr/hort/byg/. Additional Resources Report on the National Stakeholders Conference on Honey Bee Health Proceedings from a stakeholder conference organized and conducted by members of the National Honey Bee Health Stakeholder Conference Steering Committee on October 15-17, 2012 in Alexandria, VA. http://www.usda.gov/documents/ReportHoneyBeeHealth.pdf Honey Bees and Colony Collapse Disorder USDA Agricultural Research Service (ARS), Last Modified: May 7, 2013 http://www.ars.usda.gov/News/docs.htm?docid=15572 Troubling Honey Bee Shortage in California Almond Orchards University of California Davis Department of Entomology and Nematology, Feb 8, 2013 http://entomology.ucdavis.edu/News/Troubling_Honey_Bee_Shortage_in_California _Almond_Orchards/#  |