It was a pleasure to visit the 40th Annual Tri-County Beekeeper’s conference in Wooster, OH again this March. I missed last year but made sure to attend this year with both Randy Oliver and Jamie Ellis on board as speakers.
The focus, and rightfully so, for both Jamie and Randy was the Varroa mite. I follow Randy’s website updates throughout the year, especially his “blue towel” notes, with great interest.
Dr. Jamie Ellis in particular was fun to listen to as I’d not had the opportunity until this conference to hear him speak. He is a professor at the University of Florida, married with four children, one of which sat with us at his presentations watching an iPad with headphones on. :) Here’s a brief bio on him:
Dr. Ellis is the Gahan Associate Professor of Entomology in the Department of Entomology and Nematology at the University of Florida. At the University of Florida, Dr. Ellis has responsibilities in extension, instruction and research related to honey bees. Regarding his extension work, Dr. Ellis created the UF, South Florida, and Caribbean Bee Colleges, and the UF Master Beekeeper Program. As an instructor, Dr. Ellis supervises Ph.D. and masters students in addition to offering an online course in apiculture. Dr. Ellis and his team conduct research projects in the fields of honey bee husbandry, conservation and ecology, and integrated crop pollination.
There was much value in his presentations, especially for newer beekeepers or those who aren’t paying enough attention to varroa. Jamie started at a high level and attempted to help us understand both some misconceptions and the harsh realities regarding mites in the U.S. that he has tracked carefully since at least 2000.
I might distill down the key takeaways from my perspective as follows:
- Years of data since 2006 are showing that poor queens, nutrition, and most importantly, MITES are the major players year after year in killing our bees — not CCD, and not pesticides although chem is of course an important factor.
- Sample for mites. Sample for mites. Sample for mites. Alchol wash is best. We should be sampling in Ohio probably every couple months, more in warmer climes. We should be careful to obtain before and after data to ensure our treatments were effective.
- As a general rule, treat when you hit 3 mites per 100 bees (3%) and you should sample 20% of your bees in small apiaries, spot checking in a large operation. Above that threshold and you can expect a collapse is coming.
- All the data on treatment options to make educated decisions can be found at in incredible website Honey Bee Health Coalition and in particular their varroa page: Tools for Varroa Management
- The PDF found on that page is most helpful, Tools for Varroa Management
- They are learning that varroa mites feed on bee fat, not on bee blood as commonly communicated (this has many implications for future treatment ideas)
Lots of good stuff as you can see! It was well worth the time driving to Wooster and back.
I’ve been thinking long the last 18 months about the OTS methodology (brood breaks, new queens, healthy bees) and if it alone was sufficient for managing mites. At a base level, I could say “yes” but with living with the reality over five years that the best I could expect for a winter survival rate with OTS alone was around 80% and sometimes only 60%. I’m not satisfied with 60% and started playing with oxalic acid knowing that is was more of an “organic” acid that doesn’t leave residue and can be used properly and not compromise honey consumption.
By this Spring my main idea and plan was this: continue doing OTS and take advantage of this break at 21 days to do my oxalic vapor treatment. The benefits are at least three-fold:
- All mites by then are phoretic (living on the bodies of bees and not under capping) and thus susceptible to oxalic contact, making the vapor treatment very effective
- With all mites phoretic, I only have to apply the treatment once, saving much time and making this quite scalable
- Much less colony exposure to oxalic with one treatment, instead of three over many days
During one of his presentations, Jamie pulled up the PDF mentioned above. I skipped ahead while he spoke and, much to my delight, this basic idea was outlined as an acceptable plan for treatment. At the end of the document, the major treatment methods are discussed including their pros and cons. Brood breaks happens to be one of these and is the main power in the OTS method. And, like I have personally experienced, it is sometimes just not enough. The PDF indicates that additional help is needed. Conversely, the information on the oxalic treatment discusses the pros and cons. It’s main issue? Non-phoretic mites within cells out of reach of oxalic! Can you see where we’re headed? :)
With all that said, I’m confident now in my plan, which I experimented with this past year with 87% survival at this point with colonies expanding. The plan will be OTS brood breaks in April a week before swarm season and again at the end of June around summer solstice. At the 21+ day mark, I will do one treatment of oxalic vapor (with the Provap tool). And, I will up my game with alcohol wash sampling every other month, starting in April.
For those beekeepers wanting to be “treatment free” I think OTS offers one of the best methods, but I don’t think you can slide by without consistent and quality sampling for mites using an alcohol wash. You could be harming other beekeepers around you and, of course, your own bees if you get a mite problem in one or more of your hives. I personally think the responsible thing is to sample and know your mite rates. For those of you okay with oxalic as I am, I think the plan above is solid.