Bees grooming, shaking and biting mite

Already in 2002 Sven-Olof Ohlsson in Munsala Finland filmed bees grooming, shaking and biting mites. I have published two of his video clips on YouTube for him. You can see one here where the the mite had attached fast between thorax and the abdomen. The poor bee seemed to never stop shaking to get the other bees to help her. Ohlsson stopped filming after 20 minutes, but the bee didn’t.

Here you see a successful bee removing and biting the mite. Another bee gave it a bite as well. It moved too much.

The Bee Shaker – where to take the sample

It has been discussed where to take the bees when making the test for infestation level of Varroa mites with the Bee Shaker. From a brood frame or just near the brood. The first week of May, I did a test with the Bee Shaker of a number of bee colonies. After that I inserted sticky boards to collect the natural downfall. This happened to coincide so that two colonies tested with the Bee Shaker also got sticky boards. The sample of bees for the Bee Shaker were taken from the middle of a the super just above the queen excluder.

Skakburksprovtagning A good compromise place to take the beesample from to the Bee Shaker is in the middle of the first super above the queen excluder. You don’t have to look for the queen. Not close to the entrance where the number of mites are fewer than average. And not far awav from the brood, when there are many honey supers. The number seems to vary more there.

Those colonies tested were choosen as I had found them to be potential breeders. The two colonies mentioned both had one (1) mite in the Bee Shaker out of about 350 bees, ie about 0.3% infestation level. Three weeks of natural downfall thereafter gave 7 mites from one and 8 from the other. The sticky boards covered almost the entire bottom. Let’s say I missed seeing two mites. If so it was thus about 0.5 mites per day.

Multiplying this figure with 120 I have heard gives a figure for the total number of mites in the colony. 0.5 x 120 = 60 mites in total then. The number of bees in the colonies were at least 30 000. But let’s say it was 30 000. Then 60/30000 would maybe give an infestation rate = 0.2%. But now I’ve seen reports that one should multiply by 30 (20-40). Then it will be completely different figures (in “favor” of the Bee Shaker). Collecting natural downfall should be done during the normal brood period, not in the very beginning or the very end of the brood season. In the case of the natural downfall of varroa mites, mites will also come from mites emerging from brood cells that have hatched during these three weeks. The natural downfall should therefore have given more mites compared with the Bee Shaker if these methods should have given corresponding figures. Therefore, the conclusion should be that the Bee Shaker revealed a greater proportion of the total number of mites in the hives than the natural downfall did.

The Bee Shaker could therefore be trusted to be an enough reliable tool to show infestation levels of Varroa mites, when samples are taken close to the brood, but not from brood frames.

Varroa resistant worker bees

Magnus was a beekeeper in his youth in western Sweden. He quit in 1996 but started again in 2013 with his wife Ulrika. Then they bought from an older beekeepers a pavilion with seven bee colonies, most of which were splits, new colonies.

Varberg1 It was a big pavilion on wheels that they bought.

It was not crowded with bees where this beekeeper lived from whom they bought the bees. Maybe a couple of miles (3 km) to other bees than his. He treated with oxalic acid against Varroa once a year. Nothing more was used for keeping the Varroa population down. And he bought a Buckfast queen now and then to help the genetic variation.

Varberg2 The hives in the pavilion are long hives with 30 combs 12″x12″ (30 x 30 cm).

The pavilion was moved to Magnus and Ulrika in September. They saw wingless bees from three colonies. Two of these were splits from the third. Of the other four were at least two splits from one of the rest, No. 9. The fourth, No. 10, appeared to be related to No. 9, because of the behavior and appearance. Maybe No. 9 was a split from No. 10 in 2012. The argument for this is that in 2014 the queen just fell of the combs in No 10 and died. Perhaps the queen was the oldest of the two.

Magnus and Ulrika has their bees quite isolated too (about 3 km) in relation to other bees. In October 2013 they treated all seven colonies with oxalic acid. From the three with wingless bees fell very many mites due to the treatment. From the other four just about 10 mites from each. These four were also the only one to survive the winter.


Low level start in 2014

In August 2014 they treated all colonies with thymol. Now they were ten. Magnus and Ulrika wanted to bring all colonies into a low level situation concerning mites as a start for the coming years. The next year they planned to check the infestation level of mites with the bee shaker bootle and treat only those with an infestation level of at least 3% in August.

They probably did too many splits, as some were a bit weak in autumn. No. 10 was still there, but with a new Buckfast queen from a queen breeder. No split had a daughter of No. 9 or No. 10 as its queen. Only No. 9 had its original queen.

No colony had been purchased and brought into their area from “outside”. All new colonies were splits from the first four who survived the first winter with Magnus and Ulrika.

The mites that fell after thymol treatment were about as many as the previous year after the oxalic acid treatment, that is very few.

Seven survived the winter. Three splits were obviously too small and did not make it.


Bee shaker 2015

In autumn 2015, they wintered 13 colonies. They controlled the infestation rate in August with the help of the bee shaker (, ie alcohol sample of 300 bees. Only the “old” colonies were tested. Magnus and Ulrika did not want to weaken the splits made in 2015. Two of these were a bit weak in the autumn due to queen problems. If an “old” colony had more than 3% infestation rate (9 mites from 300 bees) also the splits made from it would be treated was the strategy.

Those which had higher infestation rate than 3% in August were treated with thymol. There were three colonies that had just over 3%. Only those three which no splits had been taken from. Some of the other “old” colonies had only one mite from 300 bees, i.e. 0.3% infestation level. All the others except the three were not treated.

Ten colonies survived to 2016. Two of the three dead were the weak due queen problems in the autumn. The third died of local starvation. There were some empty frames between food combs and the bee cluster.

No colony during the last two winters have died because of large levels of Varroa. Varroa is evidently not a problem. Varroa levels have always been low in these colonies that originated from bees from the No. 9 and No. 10, also in 2013.


The colonies from the No. 9 and No. 10th

What naturally would come to mind is that we have found a tiny varroa resistant local bee stock genetically, if the queens are all descended from the No. 9 and No. 10. But that is not the case! Several of the daughter colonies had received queen pupae from a queen breeder. Some had been laying queens from the same breeder. He doesn’t select for varroa resistance and use effective miticides. Still, even colonies with these queens have very small levels of varroa. But the worker bees that these queens were introduced into came directly or “indirectly” from No. 9 or No. 10. Some splits from No. 9 were made in 2015. The other “mother colonies” were splits made in 2014 from No. 9, though with queens from a Buckfast queen breeder. These colonies are not ffsprings genetically, “only” “social offsprings” through the worker bees. The colony No. 10, is the social offspring of the original No. 10. Eight colonies are social offsprings of No. 9. No. 9 have the original queen. Only No. 9 have a “true” varroa resistant genetic set up.


Naturrum 2016

The first weekend in April 2016, I had a lecture at the Visitor Centre at Getteron at the west coast of Sweden close to the little town Varberg. I talked about breeding bees resistant to varroa. In the afternoon there were some workshops. One on how to check the infestation level of Varroa with the Bee shaker. The other how to make dish cloth pieces with thymol to treat against Varroa.

Varberg3 Magnus and Ulrika pouring alcohol in the Bee shaker. Somewhat more.

Magnus had brought a colony that hadn’t been treated against varroa the previous year. The queen was an introduced egg-laying Buckfast queen from a queen breeder. A queen which was not selected for varroa resistance. We hoped it would be a substantial amount of varroa in the colony so there would be some to count at the bottom of the Bee shaker.

Varberg4 The fourth comb from the rear with a lot of bees on it but no brood, to minimize the risk of including the queen.

Varberg5 The bees were shaken into a corner. With a measuring cup a little more than 1 dl bees were talken and poured into one half of the Bee shaker.

Varberg6 After the bees had been poured into one half of the Bee shaker the lids were screwed on top. Then the alcohol was poured on the bees from the other half. This half was then screwed to the rest. Now the Bee shaker was shaken for one minute. Turned around, still shaken until all the alcohol had went down in the lower part.


Too few mites

In August 2015 it was one mite in 300 bees in that test colony at the workshop. Now April 2 the colony was a strong and healthy colony of bees filling the box that had been the winter room. The bees were very calm and sampling went well. I lifted the fourth comb from the rear, with no brood, but close to the brood. To our “disappointment” it showed only one mite in 300 bees. One can truly say that we were surprised.

Varberg7 When all the alcohol had went down, the Bee shaker was lifted above the head and the mites were counted on the bottom of the Bee shaker.

How could this colony be varroa resistant? And No. 9? And the colonies that were made with bees from No. 9 but with no daughter queen from No. 9. All Magnus’ and Ulrika’s current colonies and their social offsprings have demonstrated surprisingly low amounts of mites all of the years with them. Although their queens are not genetically related to the original resistant colonies. They are though social offspring, as described above what that means.


The explanation

I had in my lecture talked about the experience of Hans-Otto Johnsen and Terje Reinertsen in Norway that can hardly be explained otherwise than that worker bees in resistant colonies teach other bees how to control mites.

Sampling with the Bee shaker on Getteron confirmed what I had lectured in a most interesting way.


Look for resistant bees

Now is the time for beekeepers that have had varroa in their colonies for a few years and have not yet checked the downfall of mites after treating. Check the differences of downfalls between different colonies. Especially you can discover good colonies in apiaries located somewhat isolated and in which there are not so many bee colonies. This lessen the risk for reinvasion of mites in the colonies. It’s good if the apiary have somewhat developed a stock of its own, ie no colonies or packages have been brought into the apiary in recent years and mostly queens have been bred from colonies in the apiary.

I’m sure there are many resistant colonies to be found today, but you must look for them.

You should make splits from the best ones.

The poorest colonies should not be used to make splits from, in any case you should avoid it.

You can buy Bee shakers here:


Resistant genes are important but resistant worker bees are more important

Of course, it requires a certain amount of resistant genes for a colony of bees to be able to develop resistance and be able to teach other worker bees how to control mites. When there are colonies which have developed good resistance it seems less genetic resistance quality is required to be able to be taught ability to control mites than to initially develop and learn this property.


If you find resistant colonies

If you find resistant colonies, even if they are somewhat bad tempered, swarmy, and only give small crops of honey, take care of them like golden nuggets. Move them if you can to an apiary of their own somewhat isolated, a couple of miles (3 km) to the other bees. Make splits from them and give those splits pupae bred from good tempered bees, reluctant to swarm and high producing.. Then continue to do splits following year from the best varroa resistant colonies and let them make their own queens. Doing so also from the original resistant colonies and let them make their own queens. Now there are good drones in respect to other good qualities from the previous year’s new colonies. Continue the following years to replace the poorest queens with those bred from the best in the apiary.

Treatment select for increased reproduction rate

Varroa mites multiply in bee larvae. After they come out of the cell when the bee is fully formed, they sit on the adult bees and suck hemolymph.

It was observed many years ago that during the brood period of the bees, 2/3 of the mites was found in the capped bee brood cells while 1/3 was on the bees.

VarroaBin2 Varroa mites on bees. Many years ago 1/3 of the mites were sitting on bees while 2/3 was found in the capped brood. Today this has changed to 15% and 85%. (Photo: Anders Berg)

If the mites had been sitting longer time on the bees than they did, before they returned into a brood cell, a greater proportion than 1/3 had been found on the bees. If they had been sitting less time there would have been a smaller proportion found on adult bees. The shorter the time the varroa mites are sitting on adult bees, the faster they return into a new brood cell to reproduce. This would increase the speed of varroa reproduction in the bee colony.

It is thus from the beekeeper’s and the bee colony’s point of view desirable that the mites are sitting as long as possible on the bees, resulting in a slower development of the varroa population. So, if the proportion of mites had been ½ on the bees and ½ in capped brood, this would have been better than that found for a number of years ago when varroa mites had arrived.

In early December 2015, two professional beekeepers from the Spanish mainland came to the small island of La Palma, one of the Canary Islands, and lectured on the varroa problem ( One of them was Manuel Izquierdo Garcia, a biologist at the University of Seville. (Thanks Rüdiger Dietrich who drew my attention to this.)

30 years ago when varroa mites came to Spain, the proportion of mites on the bees was 1/3 and 2/3 in capped brood. During the past 30 years, the mites’ behavior have changed. You could say that during the 30 years of conventional treatment of bees to kill mites, the mites have responded by spending less time on the bees to accelerate their reproduction rate. They have also changed the place on the bees they usually sit, from the abdomen to the middle part of the bee.

The result of this change has resulted in 15% are found on the bees (previously 33%) and 85% in the capped brood (previously 66%).

VarroaYngel2 Mites are sitting shorter time on the adult bees. Thus you find at a given time 15% of the mites on the bees today and 85 % in the brood. This have increased the reproduction rate of the varroa population.

Increased treatment

This change has consequences for beekeeping. It explains why we in Europe have had to increase treatment to kill mites. There are examples of recommendations in several countries where the fight starts in spring and continues throughout the season. And anyway, or should one say, maybe sometimes also because of this, the bees have difficulties to survive.

Powdered sugar

Some types of treatment will also be less effective due to this change. Treating with powdered sugar, only kills the mites sitting on the bees. One must fight very often if powdered sugar should have any effect of relevance.

Oxalic acid

If there are still small areas of capped brood when one uses oxalic acid against the mites, the oxalic woun’t have the effect one wants. This becomes more relevant when climate change means warmer winters, as it will be more common with brood in winter times, the time when oxalic usually are used. It becomes even more important keeping bees that really have brood-free periods during winter, also for treatment free beekeepers.

Treatment is a dead end

It is becoming increasingly clear that it is a dead end using all kinds of chemicals against varroa mites. And it is with the increased reproduction rate of the mites more difficult to select resistant bees and get areas with treatment free bees – which is the solution.

Focus on varroa resistance

All this show how important it is to focus on producing as varroa resistant bees as possible and develop management methods without chemicals. It is important that all beekeepers understand the problem and are involved at least somewhat.

Every beekeeper can at least try to identify which of his or her bee colonies are the least good in resisting varroa mites and replace the queen(s) in those. The simplest way is to just remove the queen in such a colony and let the bees rear a new of their own. It is not the best method, but a start. Then you can make more steps in improving your bees, depending on interest and opportunities.

The bee shaker and varroa resistance

Skak botten 2lc One mite from 300 bees.

I understand that sometimes it’s a good idea to get an idea of the infestation level of varroa mites in bee colonies. You can take samples from a couple of colonies in an apiary to get an idea when to treat. But my first concern is breeding varroa resistant bees.

I have never monitored the varroa infestation level in my colonies. I haven’t had time and I haven’t found any reason for it because I thought I had found a good compromise – treating with Thymol when I saw wingless bees on the hardboard in front of the hive entrance, checking every 10 days or so.


Good results up till now

I give a colony one or two pieces of dish wash cloth containing 5 grams of Thymol each when I see wingless bees crawling on the hard board in front of the hive. But this means I don’t treat every colony at the same time (hopefully some not at all in a season). This results in some colonies with higher mite loads not showing wingless bees yet. So these colony (-ies) will through reinvasion increase mite levels again quite quickly in those colonies recently treated.

But this way I’ve been able to develop more and more resistant bees and still produce a good crop. There have been a number of bees not producing any honey. Winter losses have been reduced from 30 % to 10-15 % (except the first year with varroa trouble when I lost 50 %).

The bees have been better chasing mites and remove infested brood. I’ve got good reports from for example Poland and Germany of low populations of varroa in colonies headed by Elgon queens, compared to other bees. And the VSH trait is becoming better and better. Daughters of my colony with the highest VSH % (80) gave colonies that in Poland dropped 2-5 mites after effective treatment while other colonies dropped more than 1000.


Thymol is useful but hinders total adaptation

I now have been aware that by having this regime I have a constant quite high varroa population in the apiaries as a whole, and thus probably a climbing virus pressure. In a way this is good as selection is done also on virus resistance.

How do I know that? Now when I’ve used the bee shaker somewhat this year I’ve seen that colonies may show wingless bees (DWV-virus) at low mite infestation. Such low infestation you didn’t expect them to do so, sometimes even as low as 2 % infestation (a daughter from a colony with high VSH trait [80%]! This experience and others similar, raise the question if very high VSH comes with higher susceptibility to viruses.). Wingless bees at 2 % infestation is totally different from a report I’ve got from a test further down in Europe. (There they normally treat effectively every year.) In that test where they didn’t treat at all, my bees didn’t show any wingless bees at 35% infestation while other bees had a lot.


How to explain the high infestation level in the test

Now I have to try to explain why my good bees could arrive at 35 % mite infestation. This is interesting and brings up another topic as well. The importance of memories of the worker bees (their knowledge how to chase mites), not only their genetics (and epigenetic history). My queens in this test down in Europe were introduced to bees that had not been selected the same way as mine, and those bees had been treated effectively every year. The bees could probably not chase mites as well as mine.

But of course the genetics from my queens would more and more influence the workers to build up a better behavior when it comes to chasing mites. When the bees have arrived at a good mite chasing mood they learn new bees born in the colony what they have achieved, more than what just come directly with the genetics. In Norway with Terje Reinertsen and Hans-Otto Johnsen experiences are achieved pointing strongly to this.

In an apiary where many colonies are non-resistant as in this European test, you get a mixture of all bees in the apiary through drifting and robbing. This is taking place more and more when the mite populations in the colonies rise. As it did in this test as the colonies were not treated at all.

In a situation when colonies are receiving a lot of mites from neighboring colonies, even the very best kind of mite chasing behavior is maybe not enough to keep mite levels low.

In the test apiary previous to this test, effective treating every year had kept the mite and virus levels low, so the mite population could grow much in the test without showing wingless bees – like in the beginning when the mite first arrives to an area. Then the virus levels are usually very low and there could be 10 000 mites and more in a colony without any signs of viruses (documented case in Sweden in 1987 when the mites were first detected on the island Gotland in the Baltic).

The bees in this test were on 5.5 mm cell size, while my bees are kept on 4.9 mm.


Also Thymol hinders total adaptation

I have talked to some beekeepers whose bees are totally treatment free since many years (Hans-Otto Johnsen in Norway, Richard Reid in Virginia and Myron Kropf in Arkansas). Their bees have now small populations of mites and are showing no wingless bees.

I have come to realize that also Thymol is a chemical that hinders the bees to fully adapt to handling the mites successfully on their own. It is in first place the epigenetic adaptation I have come to think of that is disturbed when alien chemicals (like miticides of all kinds) are present. Epigenetic changes take place when a chemical change occur due to environmental changes, like for example the presence of the mite. (But it should be said also that if you use Thymol regularly spring and late summer in a system not selecting better bees like I do, winter losses can be kept low. I know because beekeeper friends do like this.) Also Thymol like other miticides is lowering the immune system of the bees.

How do I then integrate these insights to go further in becoming totally treatment free?


A new strategy to try

I’m planning a new strategy, at least to start with in one quite isolated apiary. I have to stop using Thymol. First though I think I have to knock down the mites effectively to reduce the virus level. And then get a better control of the number of mites and take action without any chemicals if varroa populations are rising too much in colonies.


The role of the bee shaker

Here the bee shaker will play a role. And I have looked more into how Randy Oliver uses it. It’s much easier to shake a frame of bees into a bowl or pan and then with a measuring cup scope somewhat more than a deciliter (3.5 oz) of bees and pour them into one half of the bee shaker, half filled with alcohol (for example methylated spirit or rubbing[isopropyl] alcohol). Then screw it together and shake for a minute before reading the result. Compared to holding the bee shaker close to a frame side with bees and pour bees into it moving it slowly upwards, the alternative of Randy Oliver is quicker (at least for me). The next step is to test the VSH trait in the best colonies.

Skak yngelrum Start checking from one side in the uppermost box with brood. The queen hopefully will run to the brood if she is outside the brood area (probably not). The comb closest to brood you check so the queen is not there. 

Skak deciliter Shake the bees into a pan or bowl. Scope up somewhat more than a deciliter of bees (3.5 oz)

Skakburk sprit Pour the bees into one of the halfs of the bee shaker, which is half filled with alcohol. Screw the other half tight on top. Shake it for a minute.

Skak botten1lc Turn the shaker upside down and continue shaking until all the alcohol has poured down. Lift it up against the sky and count the mites. This colony had 14 mites on 300 mites and it got two pieces with 5 gram Thymol each. It showed no wingless bees.

What I hated to do

So what I’ve done so far is something I hated to do. In one quite isolated apiary I used an effective chemical miticide (only this time I promised myself) in August 2015. I wanted to use something else than Thymol to give the bees a break from that chemical. And I wanted to knock down the mite population effectively to lower the virus pressure in the apiary. I collected the knocked down mites. (In the rest of the apiaries I plan at the moment to continue as before.) The colonies that had needed most Thymol earlier in the season had the highest downfall of mites. They got probably continuously reinfested from other colonies that happened to not show wingless bees while they anyway had quite high mite loads. The defense system of these quickly reinfested colonies was probably lowered by Thymol, which made this relatively quick reinfestation possible.

One colony that hadn’t needed any Thymol at all (and very little the year before) and still had given me 80 kg (175 lb) of honey with 20 kg (45 lb) left for winter dropped less than 200 mites. And this happened in this very bad season of 2015. This colony is of course a breeder for the coming season.


The new strategy

Next year I will in this new strategy apiary make splits from the best colonies and place them in the same apiary (or if the number is enough there, place in other apiaries). In the least good colonies in this apiary (those with highest infestation level) I will kill the queen and give them a ripe queen cell bred from a good colony in this apiary. I check the number of varroa (infestation level) with the bee shaker twice a season in all colonies in this apiary. Each time it will take about 5 minutes per colony. And I look for eventual wingless bees on the hard board in front of the entrances. Before the number of mites rise too high (whatever that is), or when I see wingless bees, I plan to remove all capped brood (worker and drone brood) once or twice with a week in between. I haven’t decided what to do with those brood frames yet. Any suggestion?



More viruses due to cold weather

The weather has given the coldest May since 1962, 12 years before I started with bees. The bees have had a hard time getting enough pollen to keep up egglaying to reach optimum nectar gathering strength when summer comes.

In agricultural areas winter rape has given some nectar during the few hours with good weather. It’s still in bloom… In the forest small blueberry bushes which in many areas cover the ground has done the same. Now lingonberry flowers give nectar and pollen.

Pollen is essential as amino acid and protein source. These are used for almost every thing the bees need to function as they should, for example the immune system.

This year I’ve seen wingless bees in colonies with no big population of mites, eve if it’s somewhat bigger than it had been if the colonies had been treated with an effective miticide last year. I use thymol only when wingless bees appear, on the hardboard in front of the entrance or on the brood combs.

Nosema have probably also contributed to health problems with the bees this cold May, in combination with viruses and plant protection chemicals, it can be disastrous.

Now sun and mating temperature for honey bee queens came upon us the other day. Nature dried up. The hard boards appeared “empty”. Bees are working like maniacs. Nectar is filling the supers, even in the forest. It must be the lingonberries.

More Virus lingonblom To the left there is a Swedish blueberry plant showing some berry babies. Now lingonberries are blooming.

But happiness is not perfect. In most colonies there hasn’t been egglaying as it should this time of the year. The field bees that will fly to death will not all be replaced by hatching new bees. But if the fine weather will continue the bees may collect quite some early honey, in spite of the earlier bad weather. And here in Sweden we hope for a good amount of wild raspberry flowers.

Varroa feces, larval and pupal skins

I found a good description of what happens in the brood cell here:…44&page=14

There are good pictures of different stages in the development of the bee and of mite reproduction.

There I also find the answer to my question and it’s yes. There are more remains of the bee development than just one piece of whitish/yellowish.

The first remain is from the larva when it becomes a pupa and the second is from the pupa when it becomes a fully grown bee.

Why this is important is because I have to take in consideration the age of the pupa/bee when I remove it. Do I find “extra” remains even if the pupa has not changed into a fully grown bee (but not hatched), the extra is varroa feces and there is a mite even if I don’t see it. That can happen when the mite doesn’t have progeny. i then don’t have to find the mite to know there is one.

Varroa defecation and pupa remains

I’m checking my, as I think, most promising colonies for the VSH trait. ( After dragging out more than 1000 pupae I have learned a lot about analyzing what I see. But I understand it’s more to learn. And I’m becoming faster doing the VSH-test. I have tried a reading lens with a ring lamp + extra 2.5 reading glasses. Together 5 times enlarging. Works great.

HDRtist Pro Rendering -

All pupae leave some white remains at the bottom of the cell. Mites defecate and leaves more white stuff often little higher up on the cellwall. When there’s a whole varroa family you find quite a lot of white stuff, sometimes covering the bottom.

VSH Pupa remains

A mite without offspring leave most often just a little extra white, sometimes almost nothing (can be hard detecting such a mite, but if missed doesn’t result in too good figures). New white wax comb makes it easier to detect mites without offspring.

VSH defecation? VSH defecation2

Now some questions.

  1. Does an older pupa than a younger one (with just darkened eyes) give more whitish remains at the bottom of the cell? (Just from the pupa and not from a mite?)
  2. If you find pupa remains AND just above it a small whitish stuff, more compact like varroa defecation, (I know it could be varroa defecation) is that always varroa defecation or could it, in case with an old pupa just about to emerge by itself, be more pupa remains due to the older pupa?

This could be important questions as if it is varroa defecation there is a mite even if I can’t see it. Once I saw a mite popping out from a pupa after it had been laying for a while on the table, a pupa from such a cell. This was seen on a dark comb, where it’s more difficult to detect a single mite without offspring. Often such single mites also are not as movable as one in a cell with a whole varroa family.

Anyone out there that has detected pupae remains in the cells after dragging them out? Have you seen the varroa defecation? Differences between them, and compared to pupae remains? It would be interesting to know.

MT-colony conclusion

I have shared the performance of this colony which had almost a box of plastic small cell frames and natural positioning of these frames (as the uppermost broodbox). Which also had a tough experience with mice living in the bottom box during winter.

It gave top crop the first crop of winter rape, dandelions and some raspberry. It showed no wingless bees this year early on as it did last year. But it had an old queen. So the colony decided to shift it’s queen and did. Now they showed a few wingless bees. I concluded that was due to the declining amount of open brood to enter for the mites, son inte last brood of the old queen there was enough concentration of mites to develop some wingless bees. But to be consistent with my way of working I gave the colony 9 grams (two pieces) of thymol dish pieces. Next time no wingless bees.

My impression is that the colony is not performing less good with plastic small cell and natural positioning. Thus the conclusion is that plastic small cell frames are not negative for the bees, neither what I call natural positioning. If any of these configurations are positive is difficult to say. An overall smaller mite pressure in the apiary and the area could be the explanation. Due to epigenetic changes that have improved the bees, or/and conventional selection has done its job with the genepool in the apiary/area. Also plastic small cell frames and natural positioning may have contributed. At least plastic small cell may have good influence as there are more cells for each comb, thus faster buildup.

Europe versus USA: breeding varroa resistence

Rüdiger Dietrich’s comment is so good I made it into a post of its own as well. Thanks Rüdiger!

As a German I have of course to answer to Eriks contribution “Breeding for Varroa resistance: Germany versus USA”…:-).

When commenting about activities in the varroa resistance breeding area I guess it’s better to compare Europe versus US. Otherwise it would be too bad for Germany…

I think the main drawback for Europe compared to US is that a funded continuous breeding program is missing. The US seems to have at least 3 – Minnesota Hygienic Stock (MNHYG), Russian Honey Bee program (RHB) and VSH program, which all seem to have shown valuable outcomes. Moreover, the organic beekeeping community in the US, e.g. Ed and Dee Lusby, Michael Bush, Dennis Murrel and others have been innovative and could establish treatment free beekeeping since many years. And this could be achieved with local bee races or no complicated bee breeding scheme!!! Their impact with small cells, comb distance, not contaminated bee wax etc. is not only logic and inspiring, it works as stated above.

Europe did of course some funded scientific investigation of Varroa and could contribute to the understanding of infestation mechanism in the 90-ies, e.g. grooming behaviour (Bienefeld, Aumeier, Thakur etc.) or VSH (Rosenkranz, Vandame). However, efforts seem to be sporadic and as already mentioned not continuous, to yield in resistant queens that are distributed via the beekeeping community.

Besides, beekeeping organizations here I can only comment on Germany with the AgT (Arbeitsgemeinsschaft für Toleranzforschung), try to connect and coordinate different breeders in order to achieve bees that combine favourable and varroa resistant traits. However, improvement ratios seem to be small up to now.

But in my eyes Europe could contribute significantly by activities of bee breeders. The idea to use already varroa resistant bees for breeding was first established by Erik Österlund (1989) and John Keyfuss (1993), who cross African bees into A.mellifera mellifera/Buckfast. John uses a Tunisian bee (Apis mellifera intermissa) and Erik Apis mellifera monticola from Kenya. The resulting Elgon bee is since a bee that needs less or even no varroa treatment. The same is true for Kefuss bees and he gain merits by bringing this topic into broad public interest with his “World varroa challenge”.

This approach was copied by Rinderer (RHB), who used Russian bees that lived since 200-250 years with varroa mites and hence, should have developed resistance traits. The same idea was practically followed by P. Jungels (Buckfast – Primorski mixes) and J. Koller (pure Primorski) (Primorski synonyme for Russian bees) in Europe, who contributed significantly by providing varroatolerant queens to the European beekeepers.

A guy that use local (carneolian) bees for his breeding program is Alois Wallner from Austria, who has bred since 1990 for bees that groom and kill varroa mites by removing their legs. The result is now a bee that kill nearly every mite (varroa killer factor 100). Additionally his bees express VSH behaviour and hence, bees need only few or no treatment with formic acid.

In my opinion one brave European guy need to be mentioned as well which is Juhani Lunden in Finland He managed in a brute force approach to breed varroaresistant bees, which are not treated since 2009. He used a strong selective pressure to achieve his goal and hence, other traits as gentleness or honey crop might be compromised.

So taken together, these efforts need to put on a strong base in Europe as well and both, the spread of “resistant genes” by suitable queens and by suitable programs need to be pushed and furthermore the usage of organic beekeeping principles that result in treatment free bees should be distributed. That includes the courage of not using treatments to outselect non optimal strains. Here the community in Europe is already on the way see (Germany and Spain), but Europe should definitely speed up and learn the positives from the US. This is especially true for the scientific sector and funded EC programs.