The Plight of the Bee: An Update on Colony Collapse Disorder
By: Amie D. Moody, Ph.D.
Honey bees serve a vital economic role pollinating over 90 commercially grown crops and providing a $15 billion annual increase in crop value. However, the health of United States (U.S.) honey bee colonies is in jeopardy. This is due, in part, to Colony Collapse Disorder (CCD), which began ravaging honey bee colonies in 2006. CCD is unique from other causes of honey bee losses, such as large exposures to pesticides. It is characterized by few to no adult honey bees in the hive, absence of dead honey bees but the presence of immature bees, and a live queen. From the winter of 2006-2007 through 2010-2011, beekeepers reported losing an average of 30% of their colonies each winter1, an average that is well above the 15% over-winter loss rate cited as being economically feasible. These data, combined with a report published by the National Academy of Sciences in 20073 stating a demonstrable decline in the honey bee population since 1947, spurred large-scale efforts to understand and to prevent the continued loss of honey bee colonies. Otherwise, agriculture that relies heavily on honey bee pollination, like the California almond industry, which is entirely dependent on commercial bee pollination, could be in trouble.
During a two-day meeting in June 2007, a rapid response group of academic, private, and government scientists formed a CCD Steering Committee and released the Colony Collapse Disorder Plan2. The plan outlined the following areas of emphasis: creation of surveys targeting overall honey bee colony production and health, and collection of the data; expansion of sample analysis to more completely determine bee exposures to toxins, pests, and pathogens; use of this information to craft hypothesis-driven research; and finally, while the first three steps are underway, formulation of mitigative and preventative measures to stabilize, and improve bee colony health. Since the CCD Plan was published, scientists have focused on four potential causes of CCD: pathogens, parasites, management stressors, and environmental stressors4. In each category, there seems to be at least one culprit that is frequently associated with colonies affected by CCD. The most commonly observed pathogens include the gut fungi, Nosema ceranae and Nosema apis. Parasites like the varroa mites are also frequently found in CCD colonies. There are several management stressors that may contribute to CCD, such as overcrowding of bee yards, reduction of genetic diversity, and increased stress caused by the transportation of colonies to several locations across the country. Key environmental stressors include reduction in diversity and/or quality of available nectar and pollen, and bee exposure to pesticides. Yet, despite the years of research, and the identification of many putative causes of CCD, no single, definitive cause of CCD has been identified.
The largest hurdle to understanding, and thus reversing, the loss of honey bee colonies is the lack of long-range data tracking colony health4,5. Although honey bee colony numbers have been tracked since 19473, there have been no standardized methods to track bee colony health. The Bee Informed Partnership (beeinformed.org) is a coalition of researchers, supported by the United States Department of Agriculture and the National Institute of Food and Agriculture, who have been collecting honey bee colony data since the winter of 2006-2007 via an annual survey sent to beekeepers. The winter of 2010-2011 was the first year that the survey began asking questions about the health and management of colonies across the country. These more detailed surveys are sent to all classifications of beekeepers (i.e., commercial and “back yard” beekeepers), and assess colony losses region-by-region; ask beekeepers about what measures, if any, are used to control pest and/or pathogen infestations; and probe general colony management tools/techniques. Bee Informed staff also work directly with beekeepers to gather more data about specific pests and diseases, and to validate trends revealed from the survey information. In October 2014, Bee Informed partnered with the University of Maryland College Park to initiate crowd sourcing for the Sentinel Hive Scale Project6. The Sentinel Hives are designed to monitor colony health in “real-time.” Hive scales will track colony weight over time; colonies will be tested monthly for diseases; traps will collect pollen brought to the colony, which will then be screened to determine the diversity of the bees’ foraging. The idea is that these Sentinel Hives will provide guidance for the best colony management practices and serve as early warning systems for colonies in distress. It is hoped that this detailed monitoring of honey bee colony health over time will finally provide workable solutions to restore the long term health of these economically vital pollinators.
- United States Department of Agriculture. Report on the National Stakeholders Conference on Honey Bee Health. October 2012. http://www.usda.gov/documents/ReportHoneyBeeHealth.pdf
- CCD Steering Committee. Colony Collapse Disorder Action Plan. July 2007. http://ars.usda.gov/is/br/ccd/ccd_actionplan.pdf
- Committee on the Status of Pollinators in North America, National Research Council. Status of Pollinators in North America. 2007. http://www.nap.edu/catalog/11761/status-of-pollinators-in-north-america
- United States Department of Agriculture, Agriculture Research Service. Honey Bees and Colony Collapse Disorder. http://ars.usda.gov/news/docs.htm?docid=15572#research
- Smith, KM, Loh, EH, Rostal, MK, et al. 2013. Pathogens, Pests, and Economics: Drivers of Honey Bee Colony Declines and Losses. EcoHealth. Vol. 10, p 434-445.
- Jones, A. Our University of Maryland Crowd Funding Campaign is Live! October 2014. http://beeinformed.org/2014/10/our-university-of-maryland-crowd-funding-campaign-is-live/