Preliminary Results from the 2023-2024 US Beekeeping Survey: Colony Loss and Management

Note: This is a preliminary analysis. A final report is being prepared for publication in a peer-reviewed scientific journal at a later date.

Agostina Giacobino¹, Nathalie Steinhauer², Samantha Brunner^3,4, Natasha Garcia-Andersen⁴, Dan Aurell¹, Stephanie Rogers⁵, Geoffrey Williams¹

¹ Department of Entomology & Plant Pathology, Auburn University, Auburn AL, USA; ² Department of Horticulture, Oregon State University, Corvallis OR, USA; ³ North Dakota Department of Agriculture, Bismarck ND, USA; ⁴Apiary Inspectors of America, Sterling ND, USA; ⁵ Department of Geosciences, Auburn University, Auburn AL, USA

Corresponding authors: azg0223@auburn.edu (AG), steinhan@oregonstate.edu (NS) & williams@auburn.edu (GW)

There has been a collective effort since 2007 to quantify and describe colony losses in the United States. First led by the Bee Informed Partnership in collaboration with the University of Maryland, Auburn University, and the Apiary Inspectors of America (vanEngelsdorp et al.,2010; Steinhauer et al., 2014; Kulhanek et al., 2017; Bruckner et al., 2023; Aurell et al., 2024), data collected by the surveys have contributed to our understanding of long-term honey bee colony loss trends across years and regions (Overturf et al.,2022) , as well as the identification of important risk and protective factors (Seitz et al., 2016 Kulhanek et al., 2017; Steinhauer et al., 2021).

For the 2023-2024 beekeeping year, Auburn University and Apiary Inspectors of America (AIA) ran a complementary national survey of managed honey bee colony losses and beekeeping practices, with the support of Oregon State University, to further contribute to the long-term monitoring of managed honey bee colony losses in the United States. This survey used a different questionnaire and new online survey platform for collecting data.

The survey was available online for participants from May 1 to May 31, 2024, and covered the period between April 1, 2023 and April 1, 2024. Two versions of the survey were available on the AIA website – one for small scale beekeepers managing fewer than 50 colonies, and one for large-scale beekeepers managing more than 50 colonies. Key questions of the survey allowed for the quantification of managed colony loss experienced by beekeepers, as well as the identification of key management actions.

For the 2023-2024 survey, 1,652 beekeepers provided valid responses from across the United States. These beekeepers collectively managed 337,134 colonies on October 1, 2023, representing 13% of the estimated 2.51 million managed honey-producing colonies estimated to be in the country in 2023 (USDA NASS, 2024).

Like previous surveys, colony loss rates were calculated as the ratio of the total number of colonies lost to the number of colonies managed at risk over a defined period. Loss rates should not be interpreted as a change in population size, but rather as a mortality rate. High levels of losses do not necessarily result in a decrease in the total number of colonies managed in the United States because beekeepers can replace lost colonies throughout the year. In all cases, losses are reported with 95% confidence interval (CI) that were obtained from the distribution of bootstrapped estimates for each group of respondents (n-out-of-n method, 1000 rep). Due to the stochastic nature of bootstrap analyses, 95% CI are expected to vary slightly at each computation.

During summer 2023 (April 1, 2023 – October 1, 2023), an estimated 30.4% [20.5 – 40.2], of managed colonies were lost in the United States (Fig. 1). This was 7.6 pp higher than the running 13-year average summer loss of 22.8% that has been reported by beekeepers since the summer of 2010, when summer losses were first monitored.

During winter 2023-2024 (October 1, 2023 – April 1, 2024), an estimated 37.3% [31.3 – 44.8 CI] of managed colonies in the United States were lost (Fig. 1). This winter loss rate was 8.5 pp higher than the running 16-year average winter loss of 28.8% that has been reported by beekeepers since the start of the survey in 2008. The 2023–2024 winter loss rate was the third highest since the survey began, lower only than winters 2018-2019 (37.7%) and 2022-2023 (37.4%). The percentage of colony loss over winter 2023-2024 that was viewed as “acceptable” by beekeepers was 20.0%, which was on par with the previous ten years during which acceptable loss has hovered around 20%. During winter 2023-2024, over 45% of the surveyed beekeepers reported winter loss above this threshold.

Over the entire year (April 1, 2023 – April 1, 2024), beekeepers in the United States lost an estimated 55.1% [48.1 – 61.3 CI] of their managed honey bee colonies (Fig. 1). This is the highest loss rate reported since 2010-2011, when annual lost rates could first be determined, and is 14.8 pp higher than the running 13-year average annual loss rate of 40.3%.

Losses by operation type for 2023-2024

The honey bee industry in the United States is loosely divided into three groups of beekeepers: backyard (managing less than 50 colonies), sideliner (managing between 51-500 colonies), and commercial (managing more than 500 colonies). Commercial and sideliner beekeepers (6.9% of the surveyed beekeepers) collectively managed 96.9% of surveyed colonies in 2023-2024, whereas backyard beekeepers (93.1% of the surveyed beekeepers) collectively managed 3.1% of surveyed colonies in the 2023-2024 survey.

Different from previous years, backyard beekeepers during 2023-2024 experienced a lower annual loss rate than commercial beekeepers (45.1% [42.4 – 47.6 CI] for backyard vs 55.7% [48.9 – 62.9 CI] for commercial). This represented a lower loss year than average for backyard beekeepers (4.1 pp less than their running 13-year average of 49.2%), but a significantly higher loss year for commercial beekeepers (16.8 pp more than their running 13-year average of 38.9%).

During summer 2023, backyard beekeepers experienced an estimated loss of 24.4% [22.4 – 26.4 CI], which was 3.8 pp higher than their running 13-year average summer loss of 20.6%. Meanwhile, commercial beekeepers experienced an estimated loss of 30.9% [20.3 – 39.9 CI], which was 7.9 pp higher than their running 13-year average summer loss of 23.0%.

Similar to summer, loss rates for winter 2023-2024 were higher for the commercial beekeepers than for backyard beekeepers. Backyard beekeepers experienced an estimated loss of 30.9% [28.8 – 33.5 CI], which was 7.1 pp lower than their running 16-year winter loss of 38.0%. Commercial beekeepers experienced an estimated loss of 37.6% (31.2 – 45.7 CI), which was 10.0 pp over their running 16-year average winter loss of 27.6%. The winter 2023-2024 loss rate for commercial beekeepers was on par with the other record high losses reported during 2018-2019 (37.7%) and 2022-2023 (37.6%).

Losses by state for 2023-2024

We estimated loss rates for each individual state by including all beekeepers who reported managing colonies in that state during the survey year (whether single state or multi-state operation). Multi-state operations are also represented as a separate subgroup (MSO) in the hex maps below. An interactive web map has been created to display colony losses by state for the three time periods, Annual, Summer, and Winter. The state loss rates varied considerably over the country (Fig. 2). However, if state by state losses estimates comparisons are intended, readers should be careful to look at specific sample sizes since responses rates varied across states. Annual losses by state ranged between 17.7 – 76.2%, while summer losses ranged between 7.9 – 63.7% and winter losses between 9.3 – 70.1%. The MSO experienced 57.7, 33.6, and 38.0% losses during annual 2023-2024, summer 2023, and winter 2023-2024, respectively.

Figure 2. Colony loss rates (%) of managed Apis mellifera honey bee colonies in states, territories, and districts of the United States during 2023–2024. Green and orange colors represent loss rates below and above 30%, respectively. The grey color indicates that results are redacted for those states, territories, and districts that had fewer than 10 respondents during a season. MSO: multi-state operation; NCU: non-continental U.S. (American Samoa, Commonwealth of the Northern Mariana Islands, Guam, Federated States of Micronesia, Hawaii, Puerto Rico, Republic of the Marshall Islands, Republic of Palau and the U.S. Virgin Islands). MSO were counted in each state in which they reported owning colonies but were also reported as a separate subgroup.

Although the total number of honey bee colonies in the country has remained relatively stable over the last 21 years (~2.6 million colonies according to the USDA NASS Honey Reports), loss rates remain high, indicating that despite efforts beekeepers are still under substantial pressure to offset losses by creating new colonies every year to meet demand.

Resources

Full Abstract (PDF)

Data table- State Data (Excel)

The 2023-2024 US Beekeeping Survey is supported by the One Hive Foundation, Project Apis m., the National Honey Board, the American Beekeeping Federation, and the American Honey Producers Association.