High varroa count in recently installed nuc

Hi there,

I am new to bees this year. I have a question about treating varroa:

On June 23, I installed a 4-frame nuc into an 8-frame langstroth hive. The bees have made a good start on filling out the 2 frames adjacent to the 4 they came with, but have hardly touched the furthest outside two frames so they are just in a single box. There is a ton of capped brood and they are storing honey and pollen (canola in bloom).

I have a screened bottom board, and recently used the “sticky board” method to get a count on varroa levels. I realize that this is not the most accurate method, but I don’t feel like I have the bee numbers to do a wash count. Over 72 hours, there were ~53 mites on the board.

I know I need to treat, but am I okay to treat now? Most of what I’ve read says to treat in spring of late summer/early fall. I don’t expect to harvest honey this season so effect on honey isn’t a concern. Priority is to make sure they are healthy and have enough numbers to get through winter.

Location: Ontario, Canada
Avg. temps right now: Range from 20-30 degrees Celsius on any given day.
Varroa treatments I have access to: Thymovar, Mite Away Quick Strips, Apivar, Apistan
Approximate colony size: 5 frames (brood and honey/pollen stores)

Thank you in advance for any insight you might wish to provide!

Ashley

Hi Ashley, what a nicely written post. :blush: You gave all al the information we could possibly want and you have obviously thought hard about this. I think treating at this time of year is no problem if you don’t intend to harvest. It is best to treat now, rather than let them crash in October.

Given your choices, I would treat with Apivar strips. My preference would be to treat with Oxalic Acid, either vapour, or using Randy Oliver’s shop towel method (not yet fully approved, but perfectly safe).
http://scientificbeekeeping.com/oxalic-shop-towel-updates/
Randy seems to have data showing that the towels may not work as well at this time of year, so I would probably do the vapour. The disadvantage is the cost of the equipment needed, and the fact that you would have to treat 3 times at this time of year.

I’m with Dawn
Beekeeping is not that prescriptive. Your bees are in trouble and you have to treat now. Apivar is simple but have a look at vaporising Oxalic for the future. It’s what a lot of beekeepers do these days and can be repeated without harming the bees

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Thank you both for the quick responses. I’m heading to the apiary today to pick up some Apivar, and I will definitely look into Oxalic for the future. I am very new to this so the thought of vapourizing anything is a wee bit intimidating right now.

Is it fairly common for a nuc to have such a high load of varroa??

Thanks again,

Ashley

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I would answer that in a slightly indirect way. :wink:

As the nectar flow and season progresses into summer, the varroa count in all affected hives is relentlessly increasing. Even in treated hives, the count will bounce back to a surprising extent after treatment. The peak varroa population is probably in August and September, at a time when the hive population is rapidly decreasing. So in those months, the varroa load can be devastatingly high.

Another part of the problem is the current demand for untreated bees. My nucleus supplier also runs a commercial pollination business. He does not treat any of the bees he sells for nuclei, because that is what the market here demands. However, he always treats his pollination hives, because he doesn’t want to lose them over winter. He says if he didn’t treat, he would probably lose half of them, and his business can’t afford that.

If your supplier doesn’t treat, you are probably seeing the effect of that.

I am speechless at that statement!

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That is why I always treat his nucleus bees soon after receiving them. This the nuc that had DWV from the start. :hushed: He does supply them with VSH queens, but even so, I don’t trust them to control it at that point.


Sheesh!!!

Body seems unclear, is it a complete sentence?..sorry this bit is from the forum program

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Hi Dawn, Dee n others,

I’ve been on a forced I-phone n computer vacation up here ! My phone CRASHED n I lost everything … including all my passwords ! :wink: Not fun but I’m back online n slowly rebuild … not quite as bad as loosing a colony to varroa mites.

To put this note in perspective. On Father’s Day weekend I had to treat all my eight hives. Not fun ! But with rather elevated mire levels I didn’t want to wait for the Crash n Burn !

Lucky for me I’d not added honey supers n Flow-Supers yet ! I used MAQS strips in my situation. I thot about the vapor method but at the time had strips so it’s done n count temperariallly at “0” ! I usually recheck every couple weeks via drop methods to my SBB slider board.

We are in the home stretch of our main black berry nectar flow. Guessing if it warms/heats up again maybe a week or so left unless we get a later rebloom.

Guessing I’ll be seeing a rise in later August or September … Last Autumn (actually December) I had to retreat with oxide vapors then n got thru the rest of the winter.

That’s my experience with those nasty critters so far. They did get three of my biggest n healthiest last August/early September !!

Got to boggie up here,
Gerald.

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Hi Gerald, and anybody else remotely interested.
You can vape with supers on if you really have to.
Move hive aside, lift super onto a new bottom board so that returning foragers have somewhere to return to.
Seal entrance to brood box/s and vape.
When finished rebuild the hive as it was. The bees move the oxalic about so those in the supers get a dose

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I was about to say that if you do that in the US, you are a “scofflaw” as the EPA doesn’t authorize OAV with supers on. However, technically the method you describe does the vape with the supers temporarily removed, so it probably squeaks in under the wire. A bit of a “Del boy” fast one, though! :smile:

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I agree with Gerald. Luckily I have NOT had a varroa problem this year. However, they have been a real problem with me in the last 4. I have tried oxalic acid (several treatments) and Apivar with unsatisfactory results. Neither really seemed to do the job. My best results (and without issues with mortality) have been Mite-away Quick Strips to be sure.

Mite-away Quick Strips were what I thought I’d use, but the temperature restrictions made me nervous so I went with the Apivar. It’s been in for a week now - we’ll see how things are looking when I do my next hive inspection this weekend.

Apivar does NOT work quickly. The strips are slow release, and you need to leave them in the hive for the full 6 weeks to see the effect. MAQS and Oxalic Acid Vapor work very quickly, but Apivar does not create an instant mite drop. :blush:

http://entomology.ucdavis.edu/files/203955.pdf

Yes, I didn’t mean to give the impression that I would be removing the strips when I did my next hive check. I believe I have a reminder to myself to remove them on September 4 or so.

I am more wanting to get into the habit of monitoring mite counts regularly. :slight_smile:

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I didn’t think you would. I just didn’t want you to be disappointed if you don’t see a huge immediate effect, because it doesn’t work that way. :blush:

I am sure that you will do very well as a beekeeper. You are a very thoughtful person. :wink:

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I’ve been wondering at the expense and labor of carting around a battery for the vaporizer. Then just a couple of days ago I happened upon some YouTube videos of folks using hot vapor foggers with OA suspended in either 190 proof everclear or ethyl alcohol. Seems to be a perfect all around solution to me. No battery to lug and charge and the fogger I’ve been looking at cost less than the vaporizers and will accept a mason jar in place of its own plastic bottle.

I can’t find a downside, please tell me what I’m missing if you do.

I don’t. I just use a miniature car jump-starter. If you are not vaporizing 100s of hives, it is more than adequate. Mine weighs about two pounds:
https://www.amazon.com/gp/product/B01HPCB2FW/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

I have never done that, and have no experience of it. The only major concern I have is control of the dosing. If you feel you can control that, fine. The other thing in the US is that fogging is not an approved method of application. Vaporization is approved. If you are not in the US, or you don’t care about the EPA/regulations then my comments are moot. :blush: