Beesource Beekeeping Forums banner

Best Varroa Resistant Breed for NH

14K views 84 replies 19 participants last post by  NHbeek 
#1 ·
The success of treatment free beekeeping seems to depend primarily on genetics. I am trying to decide which strain(s) to start with. What would you recommend? VSH? Russian? Biting breeds?
 
#53 ·
Re: Best Varroa Resistant Breed

Are there studies of different varroa resistant breeds, what kind is the population curve of mites? VSH, Primorski, Purdue mite biters etc.

I mean is there somekind of period when mite numbers go up (maybe 5%?), after which the bees react and trow mites out. Or has some stock another strategy: mite level stays stable all season(maybe 1-2%)?

From Fernando de Noronja (?) there is a study, the levels have come down during several decades, but I don´t remember if that study said anything about seasonal variation.
 
#68 · (Edited)
Re: Best Varroa Resistant Breed

Are there studies of different varroa resistant breeds, what kind is the population curve of mites? VSH, Primorski, Purdue mite biters etc.

I mean is there somekind of period when mite numbers go up (maybe 5%?), after which the bees react and trow mites out. Or has some stock another strategy: mite level stays stable all season(maybe 1-2%)?

From Fernando de Noronja (?) there is a study, the levels have come down during several decades, but I don´t remember if that study said anything about seasonal variation.

Brettella,Martin 2107 Oldest Varroa tolerant honey bee population provides insight into the origins of the global decline of honey beeshttps://www.ncbi.nlm.nih.gov/pmc/articles/PMC5385554/
My memory failed, they write about seasonal variation in mite population.
Quote of the study:
"The infestation levels of sealed brood and adult workers were variable; both between colonies and month of collection (Fig. 3a) as previously found. All colonies were infested, with adult bee infestation levels much lower (1–2%) than found in the worker (10–20%) or drone (23–38%) brood cells. In May 2016, the six study colonies contained an average of 8400 (±2865 SD; range 4684–11839) sealed brood cells, 13894 (±4560 SD; range 7655–19982) adult bees and 1749 (±1565 SD; range 290–4647) mites per colony (Fig. 3b)."

Worker brood infestation varied between 10% ( July 2015) and 20% (May 2016). Adult bee infestation varied from 1 to 2%.

I remember reading that with Primorski they have evolved to a different direction: there are more mites on adult bees and less mites in brood cells compared to "normal bees". And from the study I linked (in my post number 56) one could suspect that a lot of seasonal variation (Primorski mite numbers went up to 4000 before "anything happend".
https://hal.archives-ouvertes.fr/hal-00891899/document

Interesting to notice that mite numbers went up until June, and after that started to decline. Similar to my personal experience.
 
#54 ·
Re: Best Varroa Resistant Breed

like many of the studys on isolated populations, when exposed to mainstream mites and virus they colaspe

the honey bee population in Fernando de Noronha has thus far evaded the catastrophic consequences of DWV and Varroa because the incredibly small and isolated population size (ca. 20–40 colonies) has meant that there hasn’t yet been sufficient time for a virulent variant to have become established in a colony. The estimated mite populations in the colonies would no-doubt result in the rapid death of the colonies if a virulent genotype of DWV was to emerge, since up to 42% of the worker brood can be infested by Varroa, levels never observed in healthy hives of European honey bees. Moreover it is just a matter of time before an overt outbreak of a virulent variant appears that has the capability to spell disaster for the bees of Fernando de Noronha. It also explains why when in 1997 six queens were transferred from Fernando de Noronha to Germany to head colonies and study whether heritable hygienic behaviour is responsible for their Varroa tolerance31. Although no difference in hygienic abilities compared to the local population were found indicating no genetic basis for the tolerance is present. These colonies all died during the winter or early spring (Peter Rosenkranz, personal communication) since the bees and mites would for the first time be exposed to the virulent DWV strains5,32 circulating in the local bee population
Brettella,Martin 2107 Oldest Varroa tolerant honey bee population provides insight into the origins of the global decline of honey beeshttps://www.ncbi.nlm.nih.gov/pmc/articles/PMC5385554/

In the US, breeds don't realy exist, the lack of-Control over mating, importation of fresh breed genetics for about 100 years, and breed standards means bees have been selected for color and traits, not necessarily genetic breeds.. the one main exception might be stock coming from a certified Russian breeder.
yes there are some II lines like the mite biters but they are not breeds per say
long and short in the US... its going to matter more on what the breeder has selected for, less on the name given it
 
#55 ·
Re: Best Varroa Resistant Breed

yes there are some II lines like the mite biters but they are not breeds per say
long and short in the US... its going to matter more on what the breeder has selected for, less on the name given it
Ok, lets not get stuck to words/names and take VSH for an example. Of course the original has now evolved in the hands of hundreds of breeders, but was there originally, right after in Harris and Harbos breeding work, studies how is the mite population dynamics going: up and down or stedy all year round, how high were the infestation rates etc.

Here is one of Primorski, fairly old one, but their mite numbers are going up, so it seems it is not going to level back to normal.
https://www.ars.usda.gov/southeast-...lti-state-field-trials-of-russian-honey-bees/
 
#58 ·
Re: Best Varroa Resistant Breed

Mite counts like that look great! Just to confirm, those were taken from bees on brood comb, not the honey storage area, and was done with an alcohol wash? And your bees have built up to a full deep and at least half of a second?

Otherwise.... using the powdered sugar shake, you can underestimate easily. Taking from older bees, you can also miss enough mites that you don't get a true picture. And if the hive is smaller, they won't have had as much brood emerge, which means they won't have had as many opportunities for mite reproduction, which will result in a low mite count but begs the question about why the hive is small. Hives that have European Foul Brood for example, have low mite counts... but they also have spotty brood and at most 1 deep of bees (maybe 5 frames top and bottom covered).

If none of the above are true, then congrats, good stock and not much mite pressure (so far) from confused foragers from elsewhere, or your hives robbing.

The need to feed is common, and does not reflect anything poorly on your hives. The amount of brood (at least 8 frames with brood, unless it's a dearth and you aren't feeding) and number of bees (majority of both boxes covered in bees by now, assuming you've been feeding) tells you the queen quality - when she's getting fed. Most first year hives need fed massive amounts of sugar water to draw out their double deeps. If they are started after the main flow, or the flow is shortened (I know OH was hit hard in May with 90s, which dried up locust trees, and tulip poplar was rained out....) then we have to step in.

Only 10% of feral swarms successfully find a home and make it through to winter, and they do it with half the space and half the bees. We want honey, so we need the queen maxed out on brood rearing and the double deeps full of bees.

Don't relax now - check again in a month, and ideally in late october too, to see if your hive went a-robbing and picked up hitchhikers. :( I am just doing OAV in early Nov to be better safe than sorry. ;/
 
#59 ·
Re: Best Varroa Resistant Breed

Mite counts like that look great! Just to confirm, those were taken from bees on brood comb, not the honey storage area, and was done with an alcohol wash? And your bees have built up to a full deep and at least half of a second?
/
I shook the bees off a couple open brood combs, mixed them around and got my half cup, dumped the remaining bees back in the hive and did a standard isopropanol wash. The big hives have been running a little under two deeps of brood for most of the year, and I will probably get a super or two of honey off them depending on how the next two months go. The hives that I had to split repeatedly or swarmed have been building up and have very little honey at the moment but do have an insane amount of brood currently.

The lack of mite pressure is an interesting point. As far as I know, there are no other beekeepers within flying distance.
 
#62 ·
Re: Best Varroa Resistant Breed

:thumbsup:

from what i can gather on the web sam and tim are completely treatment free and wca 'minimizes' the use of treatments.

your mite counts are encouraging.

it would be great to have more reporting from treatment free beekeepers located in the northeastern u.s.

if you are so inclined please consider starting a thread chronicling your experience nhbeek.
 
#64 ·
Re: Best Varroa Resistant Breed

I will most certainly be testing again in september and october. The plan is to treat if mites get over 2% because a hive needs to be in excellent health to even have a chance to overwinter.

it would be great to have more reporting from treatment free beekeepers located in the northeastern u.s.

if you are so inclined please consider starting a thread chronicling your experience nhbeek.
I would love to start a thread when I have something more to add.
 
#77 · (Edited)
Re: Best Varroa Resistant Breed

Typically I end up doing several treatments on the buckfast/italian stock I have. They always need treatment around this time of year.
The majority of my treatment free hives, have had the typical 'mite explosion' over the last month. Before I blasted them with oav this morning they averaged 3-4% mite infection. I still have a handful of colonies that are from other breeders and still have low mite counts, but I cant rate their resistance because they were previously treated colonies that were requeened this summer. The experiment with resistant stock, for this year atleast, is a failure.
no actually, I have not seen a single case of dwv this year. The hives seem very healthy and the population is peaking, but the mite counts indicate I was on the verge of mite outs.
how did you monitor and how often?
Are they placed near treated hives?
Is there drift? When did you treat your treated hives?
What comb are they on? Treated?
Are they harvested like the others?
 
#69 ·
Re: Best Varroa Resistant Breed

Interesting to notice that mite numbers went up until June, and after that started to decline. Similar to my personal experience
Are you flipping the seasons? June is there winter/late fall. I am going to guess the drop in mites is do to a drop in brood rearing do to lack of forage
"The climate of the archipelago of Fernando de Noronha, located near the northeast coast of Brazil, is tropical, hot all year round, with a dry season from August to January, and a rainy season from February to July. ... The driest period, in which it rarely rains, runs from September to December."
https://www.climatestotravel.com/climate/brazil/fernando-de-noronha
 
#72 ·
Re: Best Varroa Resistant Breed

I was hired to try and save/treat some hives that were established from packages in the spring. A few had already perished and the ground was covered in workers with DMV and numerous mites. The situation inside most of the hives was even worse. The interesting thing is one hive, despite the situation going on around it, was in perfect shape with no visible DWV or mites and beautiful brood. If it makes it through winter I will ask if I can graft from it in the spring.
 
#73 ·
Re: Best Varroa Resistant Breed

The majority of my treatment free hives, have had the typical 'mite explosion' over the last month. Before I blasted them with oav this morning they averaged 3-4% mite infection. I still have a handful of colonies that are from other breeders and still have low mite counts, but I cant rate their resistance because they were previously treated colonies that were requeened this summer. The experiment with resistant stock, for this year atleast, is a failure.
 
#76 ·
Re: Best Varroa Resistant Breed

"I spend more than 4 hours talking privately about bees with him on the conference being part of a little group interested. He is most generous with all you want to know and how his bees fare in different locations."


I'm sure that was the highlight of his day.
 
#81 ·
Re: Best Varroa Resistant Breed

Recommendation is as close to 0% infection as humanly possible going into winter. These mite levels (3 -4%) is the highest recommended treatment threshold for summer.
What was your count?

The plan is to treat if mites get over 2% because a hive needs to be in excellent health to even have a chance to overwinter.
In this case I don´t think you will ever be treatment free.
Thanks for answering my questions above.
 
#82 ·
Re: Best Varroa Resistant Breed

https://www.google.com/maps/@42.7664317,-71.4648979,115902m/data=!3m1!1e3

it may be possible but it may take time. with some luck and careful selection nhbeek may end up with a strain that can make it through the harsh winter in nh even after carrying more of a mite load in the fall.

if you zoom out on the terrain map you will see that the area around nashau is very wooded.

jmho, but if i were looking for the best varroa resistant breed for nh, i would search those wooded lands for overwintered feral survivors.

not finding any ferals surviving winter would suggest to me that the long winters there may be a little more than the european honey bee can easily thrive through, that the short season and/or limited foraging opportunities aren't quite enough to support a typical sized colony to easily reach wintering strength, or perhaps that there aren't many large cavities in the trees having the volume necessary to support a large enough colony along with adequate honey stores for wintering there.

tim ives is having tf success slightly farther south in indiana by overwintering strong triple 10 frame deeps. he also happens to have nectar availability that is off the charts which allows him to not use syrup and still get 200 - 300 lb harvests.

i might consider the triple deep set up and some of that stock if i were located in the north to see if those bees with that type management yielded similar results.
 
#83 · (Edited)
Re: Best Varroa Resistant Breed

with some luck and careful selection
I consider this a possibility for all beekeepers if they do not fear the work.

But the threshold nh gives himself seems to be too low IME. It would be interesting to see how high the mite infestation in feral swarms is.

Purchased "resistant" queen stock does not mean a lower mite count automatically, many factors play a role. Such stock IMO can be evaluated the next season if they are not treated and survive the first winter, our group experienced the F1 as much better after some adaptation happened. But you have to risk tf first and overwinter the F0.

I would use the local threshold and give the bees some % more. I would go for 5%. or treat if some defect worker bees are observed earlier. But only this colony. Shift the queen or use it elsewhere.

When I started tf I was going bond and watched the crawlers and mites on bees in a kind of naive way, thought the bees, untreated would be able to purify the hive.
But no. Not always. But some. Why that is I don´t know yet. It´s genetics or other circumstances. Working on it.

The danger starts when a colony shows defect worker bees. The first of them means : over the threshold.
Threshold of tf stock is much higher than local treated stock but maybe lower than ferals anyway. IMO. Personal experience.

I´m much more careful with monitoring and taking action now.
 
#84 ·
Re: Best Varroa Resistant Breed

with the handful of late season alcohol washes i have done i am seeing 8% to 14% infestation rates that do not result in collapse.

the winters here are relatively mild however. there are scattered opportunities for cleansing flights and even some early tree pollens sometimes in mid to late january.

t makes me wonder if there is something special about the nutrition here that perhaps results in particularly good fat bodies. i am going to communicate with the research community about the possibility for looking into that.
 
#85 ·
Re: Best Varroa Resistant Breed

with the handful of late season alcohol washes i have done i am seeing 8% to 14% infestation rates that do not result in collapse.

the winters here are relatively mild however. there are scattered opportunities for cleansing flights and even some early tree pollens sometimes in mid to late january.

t makes me wonder if there is something special about the nutrition here that perhaps results in particularly good fat bodies. i am going to communicate with the research community about the possibility for looking into that.
You have more leeway with mite counts than I do. However I think the long winter and spring splits can reset my mite counts to near zero, if only the bees can keep them down through the fall.

jmho, but if i were looking for the best varroa resistant breed for nh, i would search those wooded lands for overwintered feral survivors.

not finding any ferals surviving winter would suggest to me that the long winters there may be a little more than the european honey bee can easily thrive through, that the short season and/or limited foraging opportunities aren't quite enough to support a typical sized colony to easily reach wintering strength, or perhaps that there aren't many large cavities in the trees having the volume necessary to support a large enough colony along with adequate honey stores for wintering there.
There are rumors of feral AMMs in the area. New England kind of sucks for beekeeping, we dont get the enormous nectar flows that people to the west get, but still have the terrible winter. Some people claim to get 100lbs average, so perhaps I ought to seek out better yards.

What was your count?



In this case I don´t think you will ever be treatment free.
Thanks for answering my questions above.
mites ranged from 9-15 per 300 bees in all colonies but one. The one colony actually went from 8 mites per 300 bees before the tf queen and is now down to 0, but it was started from a really small nuc in the summer...
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top