Varroa Management
Allow me to start with an excellent assessment by Bee Culture’s Phil Craft (BC July 2015):
Perhaps beekeepers who have come to the craft in the last few decades aren’t aware of the effect varroa had when it first arrived on this continent and of how it earned its full name, Varroa destructor. Whatever the reason, every year, beekeepers all over the country lose colonies to mites and the viruses of which they are carriers, and they never know what hit them. They blame pesticides,or CCD, or habitat loss, and sometimes those really are causes, or at least significant factors. However, too, too often, the underlying cause is a lack of effective management, which allows a mite infestation to overwhelm a colony or weaken it to the point that it succumbs easily to other stressors. The most frustrating thing about these losses is that they don’t have to happen.
Watch Dennis vanEngelsdorp explain why mite management is critical for colony survival, and which methods work or don’t at https://www.youtube.com/watch?v=4bm3Y4t1NwQ
I’ve been speaking on a daily basis with one of the two beekeepers whose operations are infested, as well as others in the industry. So far, over 1000 of their colonies have been euthanized, with many more planned to be burned. As you can imagine, this is very emotional for those beekeepers, who have also been prevented from […]
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Extended-release oxalic acid for varroa management This method of application of oxalic acid is not yet approved by the EPA, so the instructions below are intended only for researchers having Pesticide Research Authorizations, Experimental Use Permits, or other permissions from their State Lead Agencies. FYI, the EPA does not require an Experimental Use Permit to […]
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Beekeeper-funded Research A Test of Thermal Treatment for Varroa Part 2 First published in ABJ April 2021 Randy Oliver ScientificBeekeeping.com Last month I covered the theory of using thermal treatment (hyperthermia) to control varroa, and some of the designs of devices on the market. I’d like to now answer some questions regarding thermal treatment. I […]
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Beekeeper-funded Research A Test of Thermal Treatment for Varroa: Part 1 First published in ABJ March 2021 Randy Oliver ScientificBeekeeping.com Last month I wrapped up the report on my testing of mite treatments suitable for application during a honey flow. A number of beekeepers have also asked me about using thermal treatment. I found […]
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Crystals from oxalic acid vaporization on bees’ bodies Randy Oliver February 2020 In order to determine how OA crystals settled on bees’ bodies after an OA vaporization, I set a graduated microscope slide and a number of dead bees under a 16-oz inverted plastic cup. I injected OA vapor briefly into a hole at the […]
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Mite Control While Honey is on the Hive Part 4 First Published in ABJ February 2021 Randy Oliver ScientificBeekeeping.com In the three previous articles in this series, I showed the results of my field trial of summer mite treatments. Now let’s go a little further with extended-release oxalic acid (OAE). A Note on […]
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Mite Control While Honey is on the Hive Part 3 First Published in ABJ January 2021 Randy Oliver ScientificBeekeeping.com In my two previous articles in this series, I showed the formal results of my field trial comparing summer mite treatments. We also have additional findings from other yards in which we applied extended-release OA. […]
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Mite Control While Honey is on the Hive Part 2 First Published in ABJ December 2020 Randy Oliver ScientificBeekeeping.com Last month I covered the setup of my field trial of summertime mite treatments, including experimental extended-release oxalic acid in glycerin. I’ll now share the results. The Results and Discussion Due to space limitations, […]
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Mite Control While Honey is on the Hive Part 1 First Published in ABJ November 2020 Randy Oliver ScientificBeekeeping.com During our hot, dry California summers most of our nectar flow may be over by early July, but if we’re lucky, our hives may still put on some harvestable honey. In any case, to control […]
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Refining the Mite Wash: Part 3 Dislodgement, Precipitation, and Separation Randy Oliver ScientificBeekeeping.com First Published in ABJ in September 2020 In my last article I showed how mites will quickly drop off the bees’ bodies if immersed in 91% alcohol. But there are still more steps remaining to separate the mites from the sample of […]
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Refining the Mite Wash : Part 4 Comparing the Release Agents Randy Oliver ScientificBeekeeping.com First Published in ABJ in October 2020 As I tested different release agents for varroa monitoring, I was often surprised by the results, which then raised new questions about why some worked better than others. So I ran a number of […]
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Refining the Mite Wash- Part 2 Mite Release Randy Oliver ScientificBeekeeping.com First Published in ABJ in August 2020 The high efficacy of hand dishwashing detergent at getting mites to release their grip on bees bestirred me to investigate this finding more deeply. What I’ve come to realize is that there are four steps involved between […]
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Refining the Mite Wash Part 1 Treatment Threshold and Solutions to Use Randy Oliver ScientificBeekeeping.com First published in ABJ July 2020 Once you’ve shaken a sample of bees, you then need to separate the mites from them. There are various recommendations for using alcohol, detergent water, powdered sugar, ether, or CO2. I’ve been using inexpensive […]
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Re-Evaluating Varroa Monitoring Part 4 WHAT ABOUT LETTING THE SHOOK BEES FLY OFF? Randy Oliver ScientificBeekeeping.com First appeared in ABJ June 2020 In my previous article I showed how the varroa infestation rate of bees varied by comb type, with those on brood frames having higher mite counts, but those on storage frames, despite showing […]
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Re-Evaluating Varroa Monitoring Part 3 HOW DOES MITE DISTRIBUTION VARY FRAME-TO-FRAME IN A HIVE? Randy Oliver ScientificBeekeeping.com First published in ABJ May 2020 In the previous articles in this series I evaluated the different methods for varroa monitoring, and then discussed the state of our knowledge as to where mites would be most prevalent […]
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