Varroa destructor mites can decimate your honey bee colony. They weaken the bees, decrease lifespan, and lead to high viral loads. What can be done?
Every major honey bee organization recommends taking regular mite counts to assess the health of your colony. An increasing mite load can spell disaster for your hive – increasing disease and limiting strength going into winter.
But what if you have been doing the mite count incorrectly?
What if your mite counts are wrong? If you are doing a sugar roll – then it’s almost a guarantee. But wait! The powdered sugar roll is endorsed by major Universities.
Yes, but it’s ineffective. It does dislodge a few mites, but it does not dislodge a majority. If it did, then dowsing your bees with powdered sugar would be effective at reducing mites overall – especially when combined with a screened bottom. Check out Randy Oliver’s page for more details about the effectiveness/ineffectiveness of the sugar roll. *Be sure to read “all parts” of his articles. He evolves his answer over time by experimentation and experience.*
The main benefit of the powdered sugar roll is low toxicity. It’s cheap, it’s easy, and it doesn’t kill the bees. You can still perform the sugar roll, but just understand that it will be less accurate than an alcohol wash. So you will need to extrapolate your mite count higher.
Washing in alcohol kills the bees. Dead bees are infinitely depressing to the beekeeper, but it’s a means to an end. You need an idea of how your bees are faring. But what if you found out the alcohol wash was also inaccurate?
What if you have been doing it wrong? Chances are – you have, and many scientific studies regarding varroa are invalid because of it.
Ever read a mite treatment study only to see they counted mites by sticky board? Not a reliable method! Well, all of our studies may be tainted by inaccurate counts, even when using the alcohol wash.
Why? Because rewashing the bees again removes more mites. Doing it a third time will uncover a few more. Mites hide under the bees scales. They are lodged in there pretty good. That’s why bees have a tough time removing them on their own and as of yet, there is no mechanical means to help them out.
When you do an alcohol wash – wash the same bees a few times. 2 or 3 times at least. The bees have already died in the first wash. Make their deaths worth it by repeating the test to get an accurate result. Alcohol is cheap, and truthfully, you can probably use the same alcohol again.
Keep this in mind when you are reading new developments in mite treatment as well. Do not settle for mite fall on sticky boards or sugar rolls or 1 time alcohol washes. A few reputable studies even go so far as to look at the bees under microscope to be sure their multiple washes have removed all the mites. These are the studies that will give us the most accurate representation of how the bees/mites are reacting to treatment.
Remember that mites prefer to hang out near the brood, and by proxy, the nurse bees. If you are sampling foragers, be consistent and stay sampling foragers. Just be aware that since a large portion of your pool will be dying per day, the mite counts will most likely swing wildly.
Most recommendations are to sample the nurse bees.
Another way to assess your mite load is to sample drone brood. Because most of us are using foundation, our brood should be predominantly worker brood. To allow your bees to create drone brood, you can either insert drone comb or do what we do and place one medium frame into the brood box. We use all deep frames in our brood boxes. We add one medium frame to the 2nd or 9th position. The bees then build comb onto the bottom of the frame, most often drone brood (sometimes honey).
Because the wax is not encased by frame, it’s very simple to cut off. It’s also easy to take a bent fork (or an uncapping fork) to open up the brood. If you’re young, you can probably see the varroa with your eyes. Otherwise, use a magnifying glass. You can get a good idea of the mite infestation by looking at these drone brood.
If they appear clear, then put the frame back in the hive. The bees may choose to recap them or they may clear them out. If they are heavily infected, sacrifice the brood. Cut the wax off and feed it to your chickens. They will relish the treat! Or simmer the whole comb in water inside a filtering bag (cheesecloth, panty hose, fruit straining bag) to render the wax for future use.
Take a hard look at your mite counting process. See if any of the above suggestions can improve your accuracy. Report back your success!
Best of luck with your bees! The varroa mite is a veritable competitor but humans have always proven to be up for a challenge. Together we can improve honey bee health!
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