Science & Technology

US Beekeepers Report Abnormally High Summer Losses After Lower Winter Losses


Beekeepers throughout the USA misplaced 43.7% of their managed honey bee colonies from April 2019 to April 2020, in response to preliminary outcomes of the 14th annual nationwide survey carried out by the nonprofit Bee Knowledgeable Partnership (BIP). These losses mark the second highest loss price the survey has recorded because it started in 2006 (4.7 share factors larger than the typical annual loss price of 39.0%). The survey outcomes spotlight the cyclical nature of honey bee colony turnover. Though the excessive loss price was pushed by the very best summer season losses ever reported by the survey, winter losses have been markedly decrease than in most years. As researchers be taught extra about what drives these cycles of loss, this 12 months emphasizes the significance of the summer season for beekeeper losses.

This previous 12 months, winter losses have been reported at 22.2%, which is 15.5 share factors decrease than final 12 months and 6.4 factors decrease than the survey common. Nevertheless, excessive summer season losses have been reported at 32.0%, which is 12.0 share factors larger than final 12 months and 10.4 factors larger than the survey common.

Worker Bees Hive

“This 12 months, summer season loss was truly the very best we’ve ever recorded, even larger than winter losses, which is simply the second time we’ve seen that, and it’s principally business beekeepers which might be driving that loss quantity, which is uncommon,” says Nathalie Steinhauer, BIP’s science coordinator and a post-doctoral researcher within the College of Maryland Division of Entomology. “In order that makes this 12 months completely different and fascinating to us, as a result of we wish to know what’s driving their losses up compared to earlier years.”

Industrial beekeepers sometimes have decrease losses than yard and smaller operations. Industrial honey bees pollinate $15 billion price of meals crops in the USA every year, so their well being is crucial to meals manufacturing and provide.

“When BIP began doing this survey, winter loss was the primary focus as a result of that interval of the 12 months was considered essentially the most difficult for beekeepers and their colonies, particularly in temperate climates,” says Geoffrey Williams, assistant professor of entomology at Auburn College and co-author of the survey. “Including summer season loss into the survey in 2010/11 was fairly revealing. For the primary time, we had the numbers to point out that loss happens all year long, and that summers should not insignificant for beekeeper losses.”

Since beekeepers started noticing dramatic losses of their colonies within the early 2000s, state and federal agricultural businesses, college researchers, and the beekeeping business have been working collectively to know the trigger and develop finest administration practices to cut back losses. The BIP annual colony loss survey, which has been carried out since 2006, has been an integral a part of that effort.

The survey asks beekeeping operations of all sizes to trace the survival or turnover charges of their honey bee colonies. This 12 months, 3,377 beekeepers managing 276,832 colonies all throughout the nation responded to the survey, representing about 10.4% of the nation’s estimated 2.67 million managed colonies.

In line with Dan Aurell, BIP area specialist primarily based at Texas A&M College, the components that go into summer season and winter losses are fairly completely different, as are the results for business beekeepers, who appear to have struggled essentially the most this previous 12 months primarily based on the survey outcomes. The well being of the queens that head manufacturing colonies is a significant factor in summer season losses. As well as, beekeepers cut up their colonies after winter to strengthen them as a finest administration apply, and the well being of these colonies at the moment is crucial to their longevity.

“Components that usually contribute to summer season loss are usually in case your splits are in poor situation or don’t have the appropriate sources, and queen failure,” says Aurell. However, winter loss is intently associated to fall administration practices, Aurell explains, resembling whether or not your colonies have good situations through the summer season to construct as much as a sturdy fall inhabitants, and if the autumn varroa mite masses have been excessive.

“I’ve heard beekeepers say that the California queen elevating season in 2019 was the worst in 30 years,” Aurell provides about one of many main queen-raising markets in the USA. In line with Aurell and his colleagues at Michigan State College, UC Davis, and Oregon State College who all work with business beekeepers, this might have been a contributing issue.

“Industrial beekeepers fairly constantly have decrease losses than yard beekeepers–you don’t get to a degree the place you’re managing greater than 500 colonies, and infrequently much more than that, with out studying good administration methods,” says Aurell. “However excessive losses for business beekeepers could be actually pricey. It might be that 400 colonies value upwards of $80K to interchange. And even when the remainder of your bees are wholesome and powerful after an enormous loss, it’s a number of labor to separate these and restore steadiness in your operation. In the event you’ve had an enormous loss, it’s usually the case that your surviving colonies are additionally in poor situation.”

Most of the summer season losses this 12 months might signify carry-over from a very poor winter final 12 months, the place BIP reported the very best winter losses it had ever recorded at 37.7%. Greater ranges of the parasitic varroa mite reported that winter could have weakened colonies going into the spring of 2019. Moreover, climate situations could have promoted brood ailments, affected the supply of mated queens after they have been wanted, or contributed to a scarcity of meals for honey bees at key occasions all year long, resembling through the almond blooms.

“Whereas these explanations are fully primarily based on what we’ve been seeing and never on information, our conversations with beekeepers and colleagues throughout the nation help these points as potential causes for the notably excessive summer season losses this previous 12 months,” says Aurell.

Along with the loss survey, BIP conducts a administration survey to attach administration practices to losses, exploring methods to handle and cut back losses total. Nevertheless, in response to the researchers, losses are a pure a part of the beekeeping business, rising and falling with the climate, varroa masses, pesticide masses, and a wide range of different components.

“Within the survey, we ask what beekeepers think about to be acceptable loss within the winter, and that quantity has crept up from 15% to 25% fairly steadily, so it’s slowly trickling into the beekeeper’s thoughts that losses have gotten worse over time, and so they have to just accept extra as a brand new regular,” says Steinhauer. “There’s all the time going to be some turnover, however it’s about what’s a standard turnover and what’s abnormally excessive, and the way BIP may also help arm beekeepers with the knowledge they should handle it.”

Williams provides, “BIP is engaged on an epidemiological strategy to essentially perceive the well being problems with bees. It’s utilizing correlational data generated by the loss and administration survey outcomes to drive extra hypothesis-driven analysis to validate and confirm findings and causes of mortality.”


The survey is carried out by the Bee Knowledgeable Partnership with information collected and analyzed by the College of Maryland and Auburn College. Survey outcomes can be found on the Bee Knowledgeable Partnership web site on this page.

Winter Loss Estimates:

Summer Loss Estimates:

Complete Annual Loss Estimates:

Back to top button