Winter Loss Survey 2012–2013 Preliminary Results
Early Results Indicate a 31.1% Loss of Managed Colonies
Note: This is a preliminary analysis. A more detailed final report is being prepared for publication at a later date.
By: Dennis vanEngelsdorp1*, Nathalie Steinhauer1, Karen Rennich1, Jeffery Pettis2, Eugene J. Lengerich3, David Tarpy4, Keith S. Delaplane5, Angela M. Spleen3, James T. Wilkes6, Robyn Rose7, Kathleen Lee8, Michael Wilson9, John Skinner9, and Dewey M. Caron10 for the Bee Informed Partnership
The Bee Informed Partnership, 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. For the 2012/2013 winter season, a total of 6,287 U.S. beekeepers provided validated responses. Collectively, responding beekeepers managed 599,610 colonies in October 2012, representing about 22.9%1 of the country’s estimated 2.62 million colonies.
Preliminary survey results indicate that 31.1% of managed honey bee colonies in the United States were lost during the 2012/2013 winter. This represents an increase in loss of 9.2 points or 42% over the previous 2011/2012 winter’s total losses that were estimated at 21.9% (Figure 1). This level of loss is on par with the six-year average total loss of 30.5%2.
On average, U.S. beekeepers lost 45.1% of the colonies in their operation during the winter of 2012/2013. This is a 19.8 point or 78.2% increase in the average operational loss compared to the previous winter (2011/2012), which was estimated at 25.3%. The difference between average loss and total loss is explained by the respondent pool: while a majority of the respondents (95%) were backyard beekeepers, they managed a small fraction of the colonies represented in the survey (6%). For this reason total loss (which is more heavily influenced by commercial beekeeper losses) is more representative of national losses.
Survey participants indicated that they considered a loss rate of 15% as “acceptable,” but 70% of them suffered losses greater than this.
Results posted online at http://beeinformed.org/2013/05/winter-loss-survey-2012-2013/.
1. Based on NASS 2012 figures
2. Previous survey results found a total colony loss in the winters of 21.9% in the winter of 2011/2012, 30% in 2010/2011, 34% in 2009/2010, 29% in 2008/2009, 36% in 2007/2008, and 32% in 2006/2007 (see Figure 1)
1. University of Maryland; firstname.lastname@example.org; 717-884-2147
2. USDA-ARS Bee Research Laboratory
3. The Pennsylvania State University
4. North Carolina State University
5. University of Georgia
6. Appalachian State University
7. USDA Animal and Plant Health Inspection Service
8. University of Minnesota
9. University of Tennessee
10. Oregon state University
posted May 2013