Mite recovery rates depend on miticides?

[richardh]

This autumn, I used three different miticides (MAQS, Apilife Var and Apiguard) on representative hives (2 per miticides) in each of 4 apiaries. All of the treatments yielded the desired reduction in mite populations with the effect of MAQS being relatively dramatic in the short term. However, the mite populations seem to have recovered much faster in the hives treated with MAQS than they have in those treated using the (relatively long duration) thymol-based alternatives. No excess mortality was observed in any of the test colinies.

The relative recovery rates surprised me, given formic acid is said to be effective in capped brood and also given its manifestly relatively dramatic impact. This has me wondering if perhaps the treatment duration and a consequent differential in the autumnal re-infection rate is at play in my results, particularly given the extended autumn we experienced this year.

Given I only tested a small number of colonies and also my experimental method probably wouldn't stand up to scrutiny in court, I'm curious about the experience of colleagues.

 

[Erichalfbee]

Maybe we should be questioning the ability of MAQS to penetrate brood cappings. I know some beekeepers do already.

 

[jenkinsbrynmair]

Maybe we should be questioning the ability of MAQS to penetrate brood cappings. I know some beekeepers do already.

the claim that it penetrates brood cappings has been questioned for as long as MAQS has been around - I'm sure that Pete Little shared some findings that indicated the claim was questionable to say the least

 

[Michael Palmer]

I've used formic only twice. The treatments, Mite Away 2 and MAQS, resulted in very little control. Almost none I would say. A good friend with thousands of colonies has used formic with a number of different application methods and formic%. He claims that the only time he killed the mites under the cappings was when the %formic was so high it also killed all the old queens and the open brood.

One time I used formic (MAQS) there was an initial mite count of 15/300 bees. After the recommended treatment time the counts were 12/300. I called NOD, the manufacturer of MAQS. They said that with high mite loads the treatment might have to be used two or three additional times. Let's see...the first treatment cost, with product and labour, $4000. For a reduction in mite population of 20%? And they want me to repeat? If the mite population is reduced by only 20% per treatment it looks like the total cost to get the mite load below treatment threshold would be upwards of $16-$20,000.

I'll use alternate methods to control varroa, and continue to rely on the nucleus colony side of my apiary to keep my hives stocked.

 

[richardh]

I've used formic only twice. The treatments, Mite Away 2 and MAQS, resulted in very little control. Almost none I would say. A good friend with thousands of colonies has used formic with a number of different application methods and formic%. He claims that the only time he killed the mites under the cappings was when the %formic was so high it also killed all the old queens and the open brood.

One time I used formic (MAQS) there was an initial mite count of 15/300 bees. After the recommended treatment time the counts were 12/300. I called NOD, the manufacturer of MAQS. They said that with high mite loads the treatment might have to be used two or three additional times. Let's see...the first treatment cost, with product and labour, $4000. For a reduction in mite population of 20%? And they want me to repeat? If the mite population is reduced by only 20% per treatment it looks like the total cost to get the mite load below treatment threshold would be upwards of $16-$20,000.

I'll use alternate methods to control varroa, and continue to rely on the nucleus colony side of my apiary to keep my hives stocked.

That's very insightful information, thank you very much.