What is it?
- Colony Collapse Disorder (CCD) is defined by the Environmental Protection Agency (EPA) as:
- Sudden loss of a colony’s worker bee population with very few dead bees found near the colony.
- The queen and brood (young) remained, and the colonies had relatively abundant honey and pollen reserves.
- The collapse of the colony comes after the worker bees have disappeared, when the food stocks have run out – as only worker bees know how to produce food, the nurse bees and young that are left cannot sustain the hive. Therefore, the hive collapses.
What causes it?
- The causes of Colony Collapse Disorder are the subject of much debate in scientific circles. One study, by a group of scientists in 2009 of colonies in Florida and California offers a partial conclusion:
- Of 61 quantified variables (including adult bee physiology, pathogen loads, and pesticide levels), no single measure emerged as a most-likely cause of CCD. Bees in CCD colonies had higher pathogen loads and were co-infected with a greater number of pathogens than control populations, suggesting either an increased exposure to pathogens or a reduced resistance of bees toward pathogens. Levels of the synthetic acaricide coumaphos (used by beekeepers to control the parasitic mite Varroa destructor) were higher in control colonies than CCD-affected colonies (vanEngelsdorp, Evans, Saegerman et. al, 2009)
- The study also provides evidence that the ‘condition is contagious or the result of exposure to a common risk factor‘ (vanEngelsdorp, Evans, Saegerman et. al, 2009). They observed that hives with CCD often occur near other hives with CCD.
- However, other studies argue particular mites or pesticides have larger parts to play:
- For example, the long known major pest of A. mellifera apiculture, the ectoparasitic mite Varroa destructor has recently received comparatively little attention, but is certainly involved. Indeed, the broad patterns of CCD coincide with continents with different pressures from V. destructor (Image below). Since African and Africanized honey bees survive without treatment for V. destructor (Martin and Medina, 2004), and the mite has not yet been discovered in Australia, this supports a central role of V. destructor for the current colony losses. (Neumann and Carreck, 2009)
What is the impact?
- The United States Department of Agriculture Agricultural Research Service (USDA ARS) created a rapid response action plan to the rise in CCD in 2007. They estimated the following value of the bee industry to US agriculture:
- Beekeeping provides pollination services for over 90 commercial crops grown in the United States.
- The honey bee adds $15 billion in value to agricultural crops each year.
- The California almond crop alone uses 1.3 million colonies of bees for pollination, approximately one half of all honey bees in the United States. Furthermore, this demand is projected to grow to 2.1 million colonies by 2012, a number nearly equal to all the colonies currently in the United States (2.4 million).
- Although this study is now 10 years old, it is the most comprehensive at expressing the value that bees bring to the US agricultural economy.
How is it changing?
- Western nations rely heavily on managed honeybees—the “movable force” of bees that ride in trucks from farm to farm—to keep commercial agriculture productive. About a third of our foods (some 100 key crops) rely on these insects, including apples, nuts, all the favorite summer fruits (like blueberries and strawberries), alfalfa (which cows eat), and guar bean (used in all kinds of products). (Holland, 2013).
- Winter losses are down in USA, but summer losses (when hives should be stronger and healthier) are on the rise causing a increase in total losses (Agricultural Research Service, USDA):
- A loss of 23.7 percent of managed honey bee colonies was reported for the 2013-2014 winter and 30.5 percent loss for the winter of 2012-2013.
- Previous surveys found winter losses of 21.9 percent in 2011-2012, 30 percent in 2010-2011, 33.8 percent in 2009-2010, about 29 percent in 2008-2009, about 36 percent in 2007-2008, and about 32 percent in 2006-2007.
- Annual colonies losses were 34.2 percent for 2013-14, 45 percent for 2012-2013, 28.9 percent for 2011-2012, and 36.4 percent for 2010-2011.
- Summer losses are arguably more concerning, as they occur when the hives should be at their strongest.
- The most up to date report from the USDA queried more than 20,000 honey beekeepers, finding that there were 2.59 million or 8% fewer honey bee colonies on January 1, 2016 than the 2.82 million present a year earlier on January 1, 2015 for operations with five or more colonies (2016).
- Jennifer S. Holland, ‘The Plight of the Honeybee’, National Geographic News, published 10th May 2013. Accessed 02/05/17: http://news.nationalgeographic.com/news/2013/13/130510-honeybee-bee-science-european-union-pesticides-colony-collapse-epa-science/
- Kim Kaplan, ‘Bee Survey: Lower Winter Losses, Higher Summer Losses, Increased Total Annual Losses’ Agricultural Research Service, USDA. Accessed 02/05/17: https://www.ars.usda.gov/news-events/news/research-news/2015/bee-survey-lower-winter-losses-higher-summer-losses-increased-total-annual-losses/
- Environmental Protection Agency, ‘Colony Collapse Disorder’. Accessed on 05/02/17: https://www.epa.gov/pollinator-protection/colony-collapse-disorder
- Dennis vanEngelsdorp, Jay D. Evans, Claude Saegerman , Chris Mullin , Eric Haubruge , Bach Kim Nguyen , Maryann Frazier , Jim Frazier , Diana Cox-Foster , Yanping Chen , Robyn Underwood , David R. Tarpy , Jeffery S. Pettis, ‘Colony Collapse Disorder: A Descriptive Study’ PLoS ONE. Accessed 02/07/17: http://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0006481&type=printable
- Peter Neumann & Norman L Carreck Honey bee colony losses, (2010) Journal of Apicultural Research, 49:1, 1-6. Accessed 02/07/17: http://dx.doi.org/10.3896/IBRA.1.49.1.01
- USDA ARS CCD Steering Committee, ‘Colony Collapse Disorder Action Plan’ 2007. Accessed 02/07/17: https://www.ars.usda.gov/is/br/ccd/ccd_actionplan.pdf
- USDA ‘Releases Results of New Survey on Honey Bee Colony Health’ (2016). Accessed 02/07/17: https://www.usda.gov/wps/portal/usda/usdahome?contentid=2016/05/0114.xml