The Bee Informed Partnership (http://beeinformed.org) recently conducted the twelfth annual survey of managed honey bee colony losses in the United States. This year, 4,794 beekeepers collectively managing 175,923 colonies in October 2017 provided validated survey responses. This represents 6.6% of the estimated 2.67 million managed honey-producing colonies in the nation (USDA, 2018).
During the 2017-2018 winter (1 October 2017 – 1 April 2018), an estimated 30.7% of managed colonies in the United States were lost (Fig. 1). This represents an increase of 9.5 percentage points over that of the previous year, and an increase of 2.8 percentage points over that of the 10-year average total winter colony loss rate of 27.9%.
Similar to previous years, backyard beekeepers lost more colonies in winter (46.3%) compared to those lost by sideline (38.0%) and commercial (26.4%) beekeepers. Backyard, sideline, and commercial beekeepers are defined as those managing 50 or fewer colonies, 51 – 500 colonies, and 501 or more colonies, respectively.
Interestingly, the self-reported ‘level of acceptable winter colony loss’ increased from 18.7% last year to 20.6% this year. Sixty-nine percent of responding beekeepers lost more of their colonies than deemed to be acceptable.
During the summer 2017 season (1 April 2017– 1 October 2017), an estimated 17.1% of managed colonies were lost in the U.S. This level is on par with summer colony loss estimates of 18.2% that were reported the previous year, and lower than the 20.9% average experienced by beekeepers since 2010-2011, when summer losses were first recorded by the Bee Informed Partnership.
For the entire survey period (1 April 2017 – 1 April 2018), beekeepers in the U.S. lost an estimated 40.1% of their managed honey bee colonies. This is 2.7 percentage points greater than the average annual rate of loss experienced by beekeepers since 2010-2011.
Selina Bruckner1, Nathalie Steinhauer2, Karen Rennich2, S. Dan Aurell3, Dewey M. Caron4, James D. Ellis5, Anne Marie Fauvel2, Kelly Kulhanek2, Kristen C. Nelson6, 7, Juliana Rangel3, Robyn Rose8,: Ramesh Sagili4, Garett P. Slater9, Robert Snyder10, Christopher A. Thoms6, James T. Wilkes11, Michael E. Wilson12, Dennis vanEngelsdorp2, Geoffrey R. Williams1
1Department of Entomology & Plant Pathology, Auburn University, Auburn, AL, USA
2Department of Entomology, University of Maryland, College Park, MD, USA
3Department of Entomology, Texas A&M University, College Station, TX, USA
4Department of Horticulture, Oregon State University, Corvallis, OR, USA
5Department of Entomology & Nematology, University of Florida, Gainesville, FL, USA
6Department of Forest Resources, University of Minnesota, St. Paul, MN, USA
7Department of Fisheries, Wildlife, and Conservation Biology, University of Minnesota, St. Paul, MN, USA
8Plant Protection & Quarantine, USDA APHIS, Riverdale, MD, USA
9Department of Entomology, University of Minnesota, St. Paul, MN, USA
10Northern California Technology Transfer Team, Bee Informed Partnership, Oroville, CA, USA
11Department of Computer Science, Appalachian State University, Boone, NC, USA
12Department of Entomology & Plant Pathology, University of Tennessee, Knoxville, TN, USA