2 reports you might review

Rich had asked that I speak at the WVBA June picnic before it was cancelled due to the heat wave. I was going to discuss two new reports. Here is that information.

New HBHC report on treating varroa mites

The Guide to Varroa Mite Controls for Commercial Beekeeping Operations lays out a vision that addresses the risks of mite resistance created by off-label pesticide use. The threat of widespread resistance to useful miticides, like amitraz, poses a serious threat to the long-term financial health of every commercial beekeeping business. Since backyard/hobbyists rely on commercials for their replacement bees they too are at risk. Continuous use of off-label pesticides such as increasing dosages and frequency of use, common alterations as a treatment becomes less effective, is a ‘fast track’ to promote pest resistance. In the case of amitraz,  instances such as uneven control for beekeepers who have been using it the longest, are an indication that amitraz might be losing its effectiveness.

This new HBHC guide is designed to help commercial beekeepers evaluate the use of a variety of varroa control methods that can be integrated into a management plan to protect their bees. It highlights the experiences of beekeepers, via case studies, who are having success as they    explore alternative strategies to limit their reliance on off-label amitraz and avoid using  unregistered products. One of the case studies is of George Hansen of Foothills Apiaries, Colton, Oregon.

In addition to documenting six case studies, all using various approaches to varroa treatment, the guide also reviews the causes and impacts of Varroa mite resistance to varroacides. It highlights control methods that can be used in an integrated pest management (IPM) strategy or a highly specific, knowledge-driven approach, referred to as       precision apiculture.

The full guide is available for free on the Honey Bee Health Coalition’s website at:  https://honeybeehealthcoalition.org/varroacontrolsguide/ Full disclosure: I was one of the authors of our newest guide.

National Bee Losses 2020-2021

Beekeepers across the United States lost 32.3% of overwinter colonies (9.6% higher than the previous winter) and through the entire year, 45.5% of their managed honey bee colonies, according to preliminary results of the 15th annual nationwide survey conducted by the nonprofit Bee Informed Partnership (BIP). The survey represents about 7% of the estimated 2.71 million colonies in the U.S. Seventy-nine Oregon beekeeper participants, keeping 20,344 colonies, 23.4% of the estimated 87,000 colonies in Oregon, had a 29% winter and 35.4% overall 35.4% annual loss.

These losses mark the second highest loss rate the survey has recorded since it began in 2006 (6.1 percentage points higher than the average annual loss rate of 39.4%). The high loss rate was driven by both elevated summer and winter losses this year. “This year’s survey results show that colony losses are still high,” said Nathalie Steinhauer, BIP’s science coordinator and postdoctoral researcher in the University of Maryland, Department of Entomology. “Not all beekeepers are affected at the same intensity, but the turnover rate of colonies is still overall higher than beekeepers deem acceptable [normal or acceptable turnover is defined at about 20%].

“Beekeepers of all types consistently lose a high number of colonies each year, which puts a heavy burden on many of them to recoup those losses in time for major pollination events like California almonds,” said Geoffrey Williams, assistant professor of entomology at Auburn University and co-author of the survey. “Colony losses remain elevated, and this year’s annual and summer loss rates are among the highest recorded.”

To read the complete article go to: US beekeepers continue to report high colony loss rates, no clear progression toward improvement (auburn.edu). Full Disclosure: Ramesh and I have participated in annual BIP surveys but this year the report was prepared only by the University of Maryland and Auburn University.

For comparison: The PNW honey bee survey included 368 Oregon backyarders (2564 colonies) and 11 Oregon commercial/semi-commercial beekeepers  (31,675), 35% of total estimated Oregon colonies. The backyard winter loss was 35%; OR larger-scale beekeepers had a 23% loss rate. The 22 WVBA beekeeper respondents had 29% loss. The loss results have been posted to http://pnwhoneybeesurvey.com I will be adding the management options and loss levels to that report.