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. http://www.elgon.es/diary/?p=914

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 (http://www.elgon.es/diary/?p=794), 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: http://www.elgon.es/diary/?p=809

 

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 (http://archiv.resistantbees.com/phoretische-varroen). 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?

 

 

Changing plans

I make notes. I’m sure you do to. How much is a good question. I made more notes as a beginner and quite some years after that. When I got well above hundred hives I began to question each kind of note and how much I could benefit from it. I wanted to save time, if I found it possible to skip doing some kind of notes.

For each year I use a fork binder. First I have a graph paper. On a horizontal line high up all the apiaries are numbered. On a vertical line to the left I make a note of the date, then an X for the apiary I have gone through that day. That’s the most important note, to be sure I don’t forget any apiary and to make sure it doesn’t take too long between my visits.

Fork Binder A spread in my fork binder.

I have made a map in the computer in the Excel application showing each apiary. On the spread is the map to the left. On the opposite side a blank graph paper for making notes. In the very early season (still winter/spring) I make note of the colony strength, how many “comb gaps” the bees occupy. Then of the progress of the colony (putting on boxes). At the end of the season, very late autumn/winter, again how many comb gaps the bees occupy.

I only make a thorough check of a colony if it doesn’t develop as expected. I check for eventual disease, if it has brood (thus a laying queen), and eventual other things to observe. I make notes only of things that depart from the average or the normal. No notes for a colony indicates an average or a normally functioning colony. Also notes are made concerning hot temper, no brood, wingless bees. I make notes of how much thymol in grams a colony get and what date, estimated amount of honey taken in kilograms (it doesn’t matter if I do a wrong estimation with 10-20%, the estimation is for comparison between the colonies).

When the season is over I compile the notes and do stats. Then I make a first probable selection concerning next year’s breeders and which queens I will shift next year. The final selections are made during May and June the coming season. Here the notes are invaluable as I tend to forget some colonies that I discover again when I’ve done the stats.

Before May comes there’s often a hard winter ahead, and a tough spring. And the spring this year was really tough, which changed the preliminary plans a lot. But the winter had been mild.

The spring was very rainy and very chilly. May was the coldest since 1962 in Sweden. The bees had small opportunities to get enough of fresh pollen for their usually quick buildup. And proteins they need desperately for everything for their rapidly expanding colony to function properly.

My bees have a higher varroa pressure than most others maybe, to let the least good colonies reveal themselves. Due to the season the immune system (rather defense system as their defense against diseases are different compared to mammals) among other things didn’t work fully due to lack of proteins. Viruses showed up even if the varroa population wasn’t big.

Maybe I should have stayed cool and not used varroa treatment, I don’t know. Varroa treatment affect the bees negatively as well, but of course not as much as mites. When should I stop treating altogether? And how should I do it? Just stop at any moment or do it in a certain way? I don’t know.

I have used more thymol this season than last. The colonies with high VSH value (VSH 80% the best one, included) and their daughters, most of them, showed wingless bees and many dwindled. I was surprised and disappointed. How was this possible? Can high VSH-value mean less good other traits than VSH? Sometimes such phenomena can appear with strong selection for strengthening a trait, as such selection often is made with the help of inbreeding.

Anyway, when I should decide which queens to breed from I went through the notes and found some interesting colonies I hadn’t payed enough attention to. Those colonies hadn’t needed any treatment for two years. So I made a VSH test. The S241 colony had three mites of 103 pupae checked. Two of the mites had no offspring. The third had one white daughter mite and no male. The H101 had one mite of 110 pupae checked, with no offspring. The neighbor colonies of these two colonies had wingless bees and many were dwindling. Of course I bred from these two good colonies.

Quite soon afterwards the H101 showed a wingless bee. I had split that colony and put the big split with the queen in the same apiary as the “mother” colony. The split with the queen lost most of its field bees that way. Was that a cause?

The S241-split was moved to the home apiary and kept its field bees. The split grew fine and is now a big colony. All the daughters are doing fine and building fine colonies. Both S241 and H101 are colonies that have shifted their queens themselves, whatever impact that may have.

To sum it up. I had to change my breeding plans quite a bit for this year, after this unusually cold and rainy spring. But I think it’s important to make good notes and from them plan for next season. Then when next season comes you know what to change and how.

The VSH 80%-colony was a disappointment and I don’t understand that, yet. There are though a couple of daughters from it that are very interesting. Those havn’t needed any treatment and didn’t show any wingless bees. One has shifted it’s queen. The second are showing a lot of bald brood and spotty brood (cleaned out brood with mites?). The queen is laying well. It seems it’s fighting reinvasion of mites and doing it well. So good that the colony hasn’t grown and hasn’t given any honey.

Bald brood One of the daughter colonies to the VSH 80-colony is fighting hard against the mites and havn’t shown any wingless bees, not yet anyway. Maybe a breeder next year.

This season is a disaster. The month of July has been the rainiest I have experienced ever. The honey crop is in average maybe 5-10 kg per hive (including winter losses and failing colonies) to compare with 25-35 kg for several years. And many colonies may need a good sugar feed to survive the coming winter.

But, the season isn’t completely over yet…

 

 

Varroa defecation and pupa remains

I’m checking my, as I think, most promising colonies for the VSH trait. (http://www.elgon.es/diary/?p=146) 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 - http://www.ohanaware.com/hdrtistpro/

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.

Jante and The Involuntary Adviser

“It is better to listen to a string, which burst,
than never to span an arc.”
Verner von Heidenstam (Swedish poet), 1902, Invocation and Pledge

 

Jante verbalize the unwritten law that says that you can not stand up and think that you are better than others in some way. It’s a fictional law of a fictional Danish town in a novel by Aksel Sandemose in the book En flykting korsar sitt spår (A refugee crosses his tracks) (1933). The closest phenomenon in the English-speaking world is what is called The tall poppy syndrome.

 Jante
1  You shall not think you are something.
2  You shall not think you’re as good as we are.
3  You shall not think that you are wiser than we are.
4  You shall not fool yourself into thinking you’re better than us.
5  You shall not think that you know more than we do.
6  You shall not think that you are more important than we are.
7  You shall not think that you are good at anything.
8  You shall not laugh at us.
9  You shall not think that someone cares about you.
10 You shall not think that you can learn us anything.
Jante Criminal Code
11 Don’t you think we know something about you?

 

Commitment
Commitment can be dangerous as it can lead to knowledge that leads to the development leading to change. If those in charge do not control the course of events. They need control of change not to risk losing control of the situation – losing control over others, over money, over development. If you have influence and power you may want to keep it. That’s when you oppose those who get involved – rather than encourage, assist and perhaps cooperate.

 

Do nothing
If you don’t do anything you don’t risk standing out and you don’t risk falling into disfavor with those who want to have control. But you can never do anything good, increase knowledge and contribute to development.

 

Do something
If you do something you risk making mistakes. A mistake, may learn you important things. And you can get ideas about how to do instead. If you do something good and it’s new, you learn something new, and also others do that, perhaps leading development forward.

 

 

2008, varroa and viruses

In spring of 2008, I had been told not to give advice to beekeepers how to combat the varroa mite. This is because I allegedly gave dangerous advice that caused beekeepers to lose their bees. The one who told me this, I had been told treated against Varroa mites only once a year trickling with oxalic acid solution in November and calculated to have 30% winter losses.

Shortly afterwards a desperate beekeeper called me in late April. He actually sought someone else he could not get through to. He asked for advice on how he would do to save his eight colonies from dying as they all showed wingless bees in different amounts. It is considered by some that a bee colony showing wingless bees is doomed to die and can not be saved. So what should I do? I was told not to give advice. But should I tell the person seeking help to let the bees die, or should I give the best advice I could? Deny a needy help, I could not.

– The mildest treatment against the already by viruses weakened bees, are probably in this case Apistan, I said, but you may not want to use that. (The mites had just arrived there and built a population and Apistan had never been used before.)

– No, said the beekeeper from east central Sweden.

– To treat these highly viruses weakened bees with acid is to lead them into death, I said. Oxalic acid could possibly have been used in November, but only really if one earlier in July/August had checked the colonies concerning the amount of mites and treated with something then if needed, so they are not weakened when Oxalic treatment comes in November/December.

– Do you know what Apiguard is? I asked.

– No, he replied, and did not know what Thymol was either.

– The best advice I can give you is to get in touch with Joel Svensson’s Bee Equipements and ask them to help you get Apiguard. Read the packaging how to use it, and apply it as soon as you can. Thymol, I think is mildest for the bees in this case.

In September the same year the beekeeper called med and thanked me for I had helped him. All his bee colonies had survived, even the most affected and vulnerable. He had also made a few splits and wintered 13 colonies.

I asked him how long time Apiguard was in the hives.

– All summer, he replied.

– Huh, I cried, but did you harvest any honey then?

– Oh yeah, was the answer.

– But didn’t the honey taste thymol, I asked.

– No, he replied.

Hmm, could it be possible? Maybe yes, maybe no. Well, you should not and need not to use Apiguard as this beekeeper did. But the most positive thing with this beekeeper was that the colonies recovered and lived. And the honey was safe to eat whether it tasted thymol or not. It was probably mostly this beekeeper and his family who ate the honey that year I believe. He certainly hadn’t a bumper crop.

The bees pollinated and did what they should. And the beekeeper was happy.

Oxalic side effects

Oxalic acid has been used for many years in Europe to kill Varroa mites in bee colonies. Recently it has been approved for use in USA.

Oxalic Trickling Photo: Anders Berg

When choosing between strategies against this mite it’s good to know all the pros and cons. Not much has been said about the negative aspects of this acid. In 2012 a study was published that hasn’t got much attention among researchers. I understand it’s why Dr Heike Ruff at Würzburgs university in Germany wrote a note about this study in the German bee magazine ADIZ no 2-2015, page 16.

The website Resistantbees.com made a reference to this and also made a summary of the study. http://resistantbees.com/blog/?page_id=2302#dt

If you succeed in using Oxalic acid correct it can help bees survive while they otherwise had died. But experiences from Sweden is that it’s difficult to have a number of years in a row with low winterlosses using Oxalic acid. If it’s only because of not successful tracking of the mite population and treating in summer when needed, not to get to high mite population when it’s time for Oxalic, I don’t know. Or treating when there’s still brood in the colony, quite useless. Or maybe damage has been adding up some years whch results in high losses with intervalls. Obviously there’s more to find out. This study cited below shows that. More beekeepers in Sweden are finding Thymol a better alternative, especially when used in spring (instead of Oxalic in winter) and after the main crop in late summer (instead of pesticide strips).

Best of all though is to work for resistant bees the best we can.

 

Sublethal effects of oxalic acid on Apis mellifera: changes in behavior and life expectancy. Oxalic acid treatment side effects
To combat the Varroa mite beekeepers can use different veterinary drugs, including organic acids such as formic acid or oxalic acid (OS). So far only the efficacy against the mite and how well the bees could tolerate the acid was evaluated for the approval of the OS. The criterion for how well the bees can withstand and tolerate the Oxalic acid is determined if the bees die (the mortality of the bees). Therefore the recommendation for treatment for Central Europe is to treat once in the broodfree time in late autumn with 3.5% sodium dihydrate OS. Higher concentrations or multiple treatments lead to high loss of bees. A study now shows that the OS-treatment, despite correct application can have harmful effects on bees. The acid affects both the performance and behavior. Treated workers neglected the brood and were inactive. Learning and memory performance for fragrances were reduced. Even the life of the bees were shortened. In addition, the acid can damage the digestive tract of the bee. Also, the bees clean frequently. Whether it is the desire of the bee, to get rid of adhering acid crystals on the body, or is a symptom of poisoning is unclear. Obviously, however, such weakened bees cannot contribute to the health of the colony. The exact effects of the OS are not known to the researchers. Further studies will show whether the effects of acid are caused by nerve damage (neurotoxicity).

 

The results of the study showed

  • That the treatment with OA led to a reduced lifespan.
  • That treated bees showed an increased self-grooming, a superior tendency to inactivity and decreased nursing behaviour….The increased self-grooming of the treated workers could be caused by the detected residues of OA on bee surface.
  • Treatment with a 3.5% solution of oxalic acid dehydrate (OA), corresponding to the dosage of 175 μg/bee, causes sublethal effects on A. mellifera. The decreased activity and nursing as well as the reduced lifespan of treated bees are aspects for a permanent damage due to the treatment with OA.
  • A decreased activity was also noticed in other studies where bees were numb for several hours (24–48 h) post application of 50 mL 4.2% oxalic acid per colony (Bacandritsos et al. 2007). Similar effects are known from bees treated with formic acid. Due to the fact that the animals did not recover from their immobility, permanent neurotoxic damage was assumed (Bolli et al. 1993). Concerning OA treatment comparable damage may have caused the decreased tasks performance in the colony, including nursing.
  • OA treatment affects the general condition of bee colonies: the workers’ performance is restrained due to the changes in behaviour, the decreased nursing of brood can lead to a lack of healthy and vital workers and the decreased lifespan could modify demographic alterations in colony age structure. Under the suggestion, that the treatment will cause damage of the digestive organs, such bees would be weaker and less vital. This could influence the general state of health of whole colonies.

 

References:

  1. Schneider, S., Eisenhardt, D., RADEMACHER, E., Sublethal effects of oxalic acid on Apis mellifera (Hymenoptera: Apidae): changes in behaviour and longevity, Apidologie, Springer Verlag (Germany), 2012, 43 (2), sid.218-225. https://hal.archives-ouvertes.fr/hal-01003525/document
  2. Ruff, Heike, Oxalsäurebehandlung mit Nebenwirkungen, ADIZ 2015; 70 (2), p.16.

The Beeshakers

‘The Beeshakers’ would be a good name for a pop/rock/soul-band/group, wouldn’t it? Why not a group of beekeepers that have control of their bees and the Varroa infestation?

Regardless of if you are on the path of becoming treatment free or treating with whatever to get rid of pathogens and parasites in your hives (and creating other problems probably along the way – that goes for both groups unfortunately). Agree we can that the world would be a better place for bees and men without killers. That’s why treatment free is the goal!

A year ago I wrote about the bee shaker: http://www.elgon.es/diary/?p=354 Here are some more tips how to get control of the Varroa situation in the hive.

When a colony has problems you can speculate and discuss about how many mites there are in the colony. If that’s why the colony is dwindling. With a high number of mites often follows virus problems, more sensitivity to plant protection chemicals and more susceptibility to Nosemas, and all of this together in a spinning wheel. You can know the mite infestation much better with this simple method that is quick and done on the spot in the apiary, with some training in a few minutes per hive.

 

Make the beeshaker

I used two plastic bottles containing peanut butter of the brand Skippy, a bee tight but not varroa tight netting, mesh size 3 mm, a plate shears, a proper sized hole saw (in this case for a 60 mm hole) and a soldering iron at 80-100 watts.

Biskak1

Get rid of the peanut butter and wash the bottles. Saw holes in the lids. Cut a piece of mesh so it fits inside the lids and covering the hole. Put one of the lids on a table, then the piece of mesh, finally the other lid upside down. Keep it all together with one hand (or some one else’s hands). Solder the caps with the piece of netting in between.

Biskak2Biskak3Biskak4

Pour one deciliter (3.5 fl oz UK; 3.4 fl oz US) in one of the bottles. Mark the waterline around the bottle with a black marker pen. Get rid of the water. Now you have calibrated the bee shaker. When you fill this jar with live bees up to the black line you have close to or exactly or somewhat above 300 bees, enough accurate so you don’t need to count them. (If you use 2/3 of a deciliter you get 200 bees.)

Biskak5

 

Make a test

Don’t take bees close to the entrance. They have bad correlation to the real amount of mites in the colony, fewer mites on those bees. Take bees relatively close to the brood, but not from a comb with the queen (poor queen if she should end up in the shaker). You may well take bees from a comb without brood, but close to the brood. In the upper brood box is a good choice if you use two brood boxes. Check for the queen! Avoid the outermost comb in the box, unless brood is close and it’s filled with bees. Most secure and quickest is if you use queen excluder and you have super(s) above it (depends on the season of course). Take bees from the center of the first super close to the excluder.

Take the jar with the black line (black color doesn’t fade so easily by the sun), hold the opening close to bees on the comb and move it from below upwards. Bees will tumble down. Hit the bottom of the jar gently against something sometimes so that the bees will be shaken down on the bottom. You then see easier when you have enough of them.

Biskak6

Before this procedure you have poured 2 deciliter of some kind of high content alcohol fluid into the other jar. The soldered caps are on top of it (there’s a hole you know you can pour through). Pour the alcohol into the jar with the bees. They die. Screw the lids with the other jar onto the jar with the bees and the alcohol. Shake it for a minute, not too hard and not too soft, “lagom” as we say in Sweden (a frequently used word when you don’t know what word to use). Turn the shaker upside down. The alcohol and the mites will go down. The bees stay above. Lift the shaker up towards heaven. The light will shine through and you can count the mites. (Live mites now killed will sink to the bottom. Dry mites from natural downfall will float. Just want to make clear the difference.) Recycle the alcohol through a fine mesh into the now empty jar to get it ready for the next hive.

Biskak7 Randy Oliver counting

Biskak8

 

Count and calculate

You may find 9 mites on your 300 bees (which you DON’T have to count, it’s enough with the calibration done to get an enough good estimation of the mite infestation). That’s 9/300 = 3/100 = 3% infestation. You can find that small or big, depending on when you did the measurement and what you are up to. Maybe you are in the middle of a breeding program for Varroa resistance. Maybe you want to find out when to treat, so you will not treat to late, or making an unnecessary treatment.

In spring, especially in a breeding program for resistance, you don’t want 3% infestation. If you’re in a breeding program you will probably take another measurement a month later. If you’re not, you maybe want to treat now, if you find something that’s good using in spring (there’s really only one option here that is least damaging in different respect, thymol).

If you get 3% after the main crop in the middle of July or in the beginning of August (or September maybe), you may decide not to treat if you’re in a breeding program. If you’re not and the bees will be without brood in November or December (on higher latitudes in Europe and Canada) and you plan to use Oxalic acid (which I don’t recommend for different reasons [though you’re the boss in your operation]) you may wait until then. If you consider pesticide strips or Apiguard (Thymol) or Formic acid, you may decide for that now.

If you get 3% in October, November just prior using Oxalic, you may decide not to use any Oxalic. Like a friend in our resistance breeding program here in Sweden. He has the limit 5% for deciding when to treat. All colonies below that limit don’t get any treatment with him.

If you treat all your colonies whatever figures you get in your measurements because you hate the mites that much, you get at least figures you can use in selecting the ones with the highest numbers. Those are the ones that should have their queens shifted in some way.

 

More to read

http://scientificbeekeeping.com/sick-bees-part-11-mite-monitoring-methods/ eller kort url: http://alturl.com/np8ez

http://svenskbihalsa.se together with Google translate

Biskak9Biskak10 Another Swedish alternative of the BeeShaker, Varroa Sampling Tool, which is for sale from http://svenskbihalsa.se