Colony Health & Varroa
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
Oxalic crystals on bees after vaporization
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...
A Test of Thermal Treatment for Varroa: Part 1
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...
A Test of Thermal Treatment for Varroa: Part 2
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...
Extended-release oxalic acid for varroa management
Extended-release oxalic acid for varroa management Updated 31 March 2026 Legality of use The question that I posed to the EPA is whether it actually had any legal justification for regulating the preparation and application of oxalic acid by beekeepers for their own use. Both New Zealand and Canada allow beekeepers to prepare their own...
The varroa incursion in Australia 4 July 2022
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...
2022 Extended-release Oxalic (OAE) Update Part 2
Contents An additional test of matrices and OA:gly ratios. 1 Cardboard Strips vs. Sponges. 3 Compostability of spent sponges. 3 A winter field trial 4 Methods. 5 Results. 9 Discussion. 11 The Elephant in the Room.. 12 Reality Check. 12 A possible easy solution for getting us legal 13 Citations and notes. 15 ...
2022 Extended-release Oxalic Update Part 3
Contents The slow effect of OAE 1 Mite turnover 3 A bothersome question 5 You don’t need to kill a single mite in order to control varroa! 5 Varroa’s world: Olfaction, taste, and touch 7 Disruption of mite sensory perception 9 “Blinding” or irritant? 9 A relevant question 9 Wrap Up 10 Citations and notes...
Walking the Walk Selective Breeding for Mite Resistance; 2022 Update, Part 1
Contents Resistance vs. Tolerance or “Survival” 1 Managed apiaries vs. natural evolution. 2 Background. 3 The necessity of Mechanical Agitators 3 The resistant colonies 6 So what’s our progress so far?. 10 A built-in lag inherent in open mating programs 13 Exhibit A: Mite-count tracking for our 2022 breeders 14 Coming. 16 References. 16 ...
Selective Breeding for Mite Resistance, Part 2; Mite Resistance and Genetic Expression
Contents The Achilles’ heel of varroa. 2 Genotype vs. Individual- or colony-level phenotype. 2 gene regulation. 3 An example of the differential expression of genes in the honey bee. 4 What Is our own bees’ mechanism(s) for Resistance?. 6 Testing for Uncapping behavior 9 Is there a Cost to the colony for resistance?. 10 Our...
Selective Breeding for Mite Resistance, Part 3; Shifting the Genetics of a Breeding Population
Selective Breeding for Mite Resistance, Part 3 Shifting the Genetics of a Breeding Population Randy Oliver ScientificBeekeeping.com The alleles necessary for varroa resistance already existed in my stock of bees, so I didn’t need to “create” anything new. What I’m attempting to do via strong selective pressure is to (1) eliminate from our...
Formic Pro and Queens in Hot Weather
Contents Formic for mite management 1 A trick for using formic pro on weak colonies 2 Queen loss in hot weather 5 Why would queens be more susceptible to formic than workers?. 6 A test of queen loss in tiny colonies. 7 Taking advantage of opportunity. 10 Trial #1 — Would foil covers reduce queen...
Formic Pro in Hot Weather — Slowing the Rate of Vapor Release
Contents Hard “Flash Treatment” vs Slow-Release. 1 Flash Treatments 1 Extended-Release Application. 2 our Follow-up experiments. 3 But Did the Wrapped Strips Kill Mites?. 8 Discussion. 9 Citations and Notes 9 Formic Pro in Hot Weather — Slowing the Rate of Vapor Release Randy Oliver ScientificBeekeeping.com First published in ABJ in October 2022 ...
Thymol — a New Application Method? Part 1
Contents “Off-Label” use of thymol 4 Thymol products for varroa control 5 Understanding Thymol 6 Reaction to the delivery matrix by the bees 6 Thymol in Shop Towels. 7 Removal and dispersion of thymol matrices by the Bees 9 Extended-Release Thymol?. 11 A Thicker Matrix. 11 moving ahead to 2022. 15 Citations and notes 15...
Thymol — A new application method? Part 2
Contents Extended-release thymol 1 The optimal release rate and placement of thymol 1 What’s The Optimal Dose?. 2 Our Field Testing. 3 The Dose-Response Curve. 12 Discussion. 12 Citations and notes 13 Thymol — A new application method? Part 2 First published in ABJ in December 2022 Randy Oliver ScientificBeekeeping.com I do a...
Testing Cotton Matrices for OAE
Contents The Fabrics to Test Preparation A Field Trial Results Discussion TESTING COTTON MATRICES FOR OAE Randy Oliver ScientificBeekeeping.com First published in ABJ January 2023 I continue to look for improved methods for application of extended-release oxalic acid (OAE), and thought that perhaps there might be an inexpensive, fully biodegradable all-cotton fabric that...
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