Anecdotal science

The expression ”anecdotal science” may well be a contradiction, as an anecdote can be far from scientific. When we are discussing bees, varroa, varroa resistance, bees behavior and similar things it may be a good thing to think about how we argue, the quality of evidences for different things, how we draw conclusions and what truth is. This is an extensive area for discussion. But I will here restrict myself to discuss little about the difference between anecdotes and science.

If someone has another opoinion than you he may try to dismiss what you say by calling it an anecdote. By that he gives the impression that reports can be either anecdotal or scientific, as if there are just two distinct divisions of accounts, either it is anecdotal and thus not of any real value when drawing correct conclusions. Or it’s scientific and a good help in knowing the truth.

Reality isn’t that simple. There aren’t just two different options when characterizing an account, an anecdotal or a scientific report.

Anecdote

An anecdote is a brief, revealing account of an individual person or an incident. It is used to illustrate a point the author want to make.

Evidence

Evidence is anything presented in support of an assertion. The strongest type of evidence is that which provides direct proof of the truth of an assertion.

Scientific evidence

Scientific evidence consists of observations and experimental results that serve to support, refute, or modify a scientific hyphothesis or theory, proposed explanations for a phenomenon.

Prediction and falsifiability

The best hypotheses lead to predictions that can be tested. The strongest tests of hypotheses come from carefully controlled and replicated experiments that gather empirical data. A scientific hypothesis must be falsifiable, implying that it is possible to identify a possible outcome of an experiment that conflicts with predictions deduced from the hypothesis; otherwise, the hypothesis cannot be meaningfully tested.

Reproducibility

Reproducibility is one of the main principles in science. It is the ability of an entire experiment or study to be dublicted, either by the same researcher or by someone else working independently.

Statistics

Often today when you are producing papers of tests, statistics play an important role when presenting results. If you get what is called a statistical significance you are said to have a result that can be trusted when used to draw conclusions. It is a difficult field and discussed in different ways.

The value of a report

There’s not just two options, anecdote and scientific report. There’s a whole range of different characteristics of a report qualifying it to be placed somewhere in between the two ”extremes”. Even these two can be difficult to clearly define.

Example

An anecdote far away from being scientific could be what often is called a testimony, a story of an event, and in this case a conclusion: ”I have a bee colony that is very aggressive. It produced double the amount of honey compared to my other colony. Aggressive colonies are more productive than calm colonies.”

Then you have a scientist that got inspired by this anecdote and formed a hypothesis of the last sentence in the anecdote above: ”Aggressive colonies are more productive than non-aggressive colonies.”

The first important issue is to define ”aggressive”. But let’s say he used a definition that everyone can recognize to be true. The next problem is to decide how many colonies to be used in the test, and the heritage of the queens in the colonies (should they be sisters for example). About half of the colonies should be aggressive and the rest non-aggressive. The colonies should be of the same strength (from when) and have the same health statues. The worker bees should be very much dominated by the queens offspring (when should the queen have been introduced).

These things I mention here are taken in consideration to avoid error sourcesto be able get a correct result. There are surely more error sources to avoid.

In the ideal situation there will be enough obtained data to produce a statistical result that falsify or supports the hypothesis. If it supports the hypothesis you can draw the conclusion that according to the knowledge we have today the most probable conclusion that comes closest to truth is that the hypothesis is true. But the result does not exclude the possibility that future result will anyway falsify the hypothesis. New knowledge may enlighten how to better design a test and avoid an error source not previously known, for example. That’s science. It always leave open for new knowledge to change the conclusions made today, in a minor or major way.

If no statistical significance has been obtained the results may anyway be pointing in a certain direction and a conclusion may be that the hypothesis is correct but more research is needed, probably with better designed tests.

Lasting learning?

In one of the recent blogposts I wrote about non-resistant bee colonies against varoa mite, learning from resistant worker bees how to deal with the mites and being resistant. It seems now that these colonies that has learned resistance have to have worker bees from genetically resistant colonies drifting into them continuously to stay resistant.

This resistance went on for at least a couple of years. I referred to experiences of Hans-Otto Johnsen and Terje Reinertsen (http://www.elgon.es/diary/?p=880)in Norway and Magnus Kranshammar (http://www.elgon.es/diary/?p=890)in Sweden.

A.) In the Norwegian cases colonies with queens from non-resistant stock originally were kept in apiaries together with resistant bee colonies. Bees are kept on small cells.

B.) In Magnus’ case it was somewhat similar as the colony of the original queen, which was the result of genetically selected resistance, and splits from it with queens of originally non-resistant stock, were kept in the same apiary. The total number of colonies was not big here. These bees were kept on large cells.

A.) A couple of years ago Hans-Otto started a variety of the first tests he made mentioned in the blogpost above. He introduced virgin queens of non-resistant stock into splits from his Elgon-stock. In this test he didn’t place these new colonies in apiaries together with his resistant stock. Instead he placed them in an apiary of their own in the forest, a lot more than 2 miles (3 km) from other bees. For two years these colonies functioned without problems concerning Varroa.

This autumn they all showed crippled winged bees. He made a test with the Bee Shaker (http://www.elgon.es/diary/?p=794). About 35 mites from 300 bees. 11-12% Varroa level. Probably there was resistance in the colonies at least the first year as long as the old worker bees were alive.

In an apiary all colonies will share more or less worker bees with each other. The whole apiary works more or less together. This depends of course also on how much worker bees from different colonies drift. In an apiary with resistant colonies, bees from resistant colonies will help keeping non-resistant colonies resistant. (And if the non-resistant colonies are many compared to for example a single resistant, this may create problems for the resistant one.)

B.) Two splits from a colony with a queen of non-resistant stock, which anyway were resistant, were moved to an apiary of their own in a forest about 2 miles (3 km) from other bees.

The mother colony of the splits was kept in the same apiary as the colony with a resistant queen (which was still alive this year). It was this resistant queen’s colony that gave bees to this mother colony of the described splits. So you could expect some drifting had occurred with resistant worker bees now living in the colony with the non-resistant queen. Thus some good resistant worker bees were living in the splits as well to begin with, until they died their natural death.

Drones from the non-resistant queen of the mother colony of the splits were of course present in these. But of course there were also drones in some colonies 2 miles (3 km) away. Those colonies were of Elgon heritage, but not of the very best variety of resistant stock. The splits got virgin queens from an Elgon colony of good resistant quality. The Varroa level was initially very low in the splits, about 0.3% (without treatment this year or the previous year).

The splits developed very well after the queens were mated and laying. In the beginning of September the Varroa level was 2% and 3.3% respectively. It had increased more than expected, but was not alarmingly high. The cell size in those splits was initially 5.4 mm, that is large cell size. (Resistant thus in spite of the large cells.) The story of those bees are told here: http://www.elgon.es/diary/?p=890. But the virgins came from established small cell size colonies since many years. The plastic combs used for increase were small cell. The 3.3% part had relatively somewhat more left of large cell combs.

131mk1 One of the splits in case B. The original large cell combs are of an old Swedish (as well as an American) size, 12”x12” (30 x 30 cm). With the help of adapters these combs are placed in boxes which hold Jumbo sized frames (448 x 286 mm) plus a deeper bottom board. The combs used for increase are small cell plastic Langstroth from Mann Lake (http://www.mannlakeltd.com/beekeeping-supplies/category/page19.html).

C.) In a project that has been going for a couple of years now, one apiary was placed a lot more than 2 miles (3 km) from other bees. The queens were of non-Elgon, non-resistant, large cell bees. They were introduced into Elgon colonies on small cells in 2013. In autumn 2014 they were moved to their test apiary and treated with a small amount of Thymol to ensure an in the test initially small and quite even population of Varroa mites. They had during 2014 been standing in apiaries with Elgon colonies. Thus probably containing some drifted Elgon worker bees. The test apiary was poor from a nectar point of view. In 2015 the Varroa level in autumn was low, around 1%. A split was made during 2015 and queens shifted to daughters made in the split in two of the units. The virgins were mated in this apiary. One of the originally queens, all had been sisters initially, were still left in its colony. The new queens were of course very inbred as the available drones were very closely related to the virgins.

In the middle of the summer 2016 the Varroa level was 3-4%. A couple of weeks later all three colonies showed crippled winged bees. They were treated with two pads with 5gr Thymol each (once) after which they recovered.

Conclusions

The experiences given here makes it probable that there are more than one component necessary for a queen of a non-resistant stock to have a resistant colony. First the colony with a non-resistant queen must become resistant. It can become resistant quickly in two ways. (One may ask whether it is desirable to deliberately do this.)

1.) Worker bees from a resistant colony can be united with a non-resistant colony through shifting the places of a resistant and a non-resistant colony. Most of the other colones in the apiary are resistant. It is uncertain how many of the colonies that should be genetically resistant.

2.) Splitting a resistant colony and giving the split(s) virgin or laying queens of non-resistant stock.

To maintain this resistance achieved, still with a queen of non-resistant stock in the colony, when the first resistant worker bees that came along with the splits are worn out and dead, new resistant worker bees have to come into the colony in some way. (Resistant worker bees are bees in colonies that show resistant behavior to such an extent that their colony can rid themselves of mites through different kind of hygienic traits.) It seems the number of resistant worker bees needed to come from other colonyies “per time unit”, are not very many. By just keeping the colony in an apiary with resistant colonies this seems to be achieved, probably through drifting of worker bees between the colonies in the apiary.

In all cases above, A, B and C there were no new resistant worker bees drifting into the colonies. In case B though virgin queens from a resistant queen were introduced, but no new bees from the original resistant stock were re-introduced. Instead new workers with probably better genetic set-up for resistance were born. But there were now probably no, or very few, resistant worker bees left that could teach newborn bees. At least this is a conclusion that is close at hand, to explain the increase of the Varroa level. It will be interesting to see what will happen further on in these two colonies. Hopefully the virgins were mated to other drones than those that came along in the splits from the genetically non-resistant queen.

No shortcut

It is thus no shortcut to get resistant bees, to split genetically resistant colonies and introduce whatever kind of queens into those splits (of non-resistant heritage)! What these experiences tell us is how important it is to increase your number of colonies and replacing the dead outs by splitting the best resistant colonies. The very best might many times be to let those splits raise their own queens. And in addition to this breed queens from good resistant colonies of good heritage in being resistant.

Factors for reinvasion

Robbing

Several years ago, it was common that there were always noticeable, even many bees flying around the ventilation and the door to the extraction room. It has become less and less bees every year. This year there have been virtually none. However wasps have been in abundance. Even though I often walked through the door in July and extracted some of the honey then. And it was no honey flow then.
Last year’s breeding queen no 1 gave many new queens working the colonies this year. That has apparently had a big effect this year. Last year, I used a lot of thymol as wingless bees appeared in many colonies. This year I barely needed to use any thymol at all. I find it hard to draw any other conclusion than that my bees have become more resistant to varroa.
However, there are a few colonies in some apiaries which are close to other Beekeepers bees where the mite level suddenly increased quite some in late July/August onwards for a few weeks. It seems to indicate so-called silent robbery from my colonies from hives that are affected by larger amounts of mites so that they do not maintain a good entrance defense.
Then when I was told about the problems some beekeepers had in Finland with imported Italian bees when it comes to how quick they were to rob and as often as these colonies must be treated against Varroa, I made a connection here.
Bees that are not inclined to rob have less problems with reinvasion of mites. Bees that have less problems with reinvasion can be called more resistant to Varroa.

Drifting

Another factor that is important for reinvasion is the tendency to return to wrong hive, to drift. I have sold a few queens to countries further south in Europe. I got some feedback recently from a beekeeper in Germany who this year introduced two Elgon queens with differing color, one light and one dark. (One of the features I do not attach great importance to is the color and therefore it can vary a lot.)
Her carniolan bees drift a lot, she has noted. Now she split a hive in two and put the two parts very close together with the entrances adjacent. She noticed that Elgon colony with striped bees contains only striped bees. The hive with without beige striped bees, had only dark bees, no bees with beige stripes. None of these colonies’ bees thus drifted to the neighbor.
It seems that part of the Elgon bees’ better resistance can be explained that they are less inclined to rob and that they drift less.

Reinvasion is worst

Last year 2015 was a bad year for the bees in more than one respect. Long cold spring and bad summer. But late summer was good as was the autumn. The bees could recover and prepare for next year.

Fresh pollen was low in spring 2015 . The immune system wasn’t at its best. And the bees couldn’t fly as much as they needed. Where nosema was present it could infect new bees instead of disappear with sick bees as those couldn’t make it back to the hive.

I treated more hives and used more Thymol last year than I had done earlier years. Early in the season I saw what was coming and decided to try some new strategies to get forward on the path to better Varroa resistance and finally get rid of chemicals.

Leif Hjalmarsson

Very often I have reminded myself of the experiences from an apiary of Leif Hjalmarsson in the southern part of Sweden. He got 5 Elgon queens from me already in 1997 and established an apiary at least 2 miles from other bees. The bees to which he introduced the queens had been treated with Apistan for about 5 years and were very low in number of mites. The bees had probably been adapted somewhat to the presence of the mite. Leif used large cell size, 5.4 mm. He never had to use any miticide on those bees until he died early this year. I do miss him! He was dear friend and a good beekeeper.

Already when we started to combine the Monticola bee with our Swedish bees there could be seen resistance traits. Therefore I had hoped that Varroa mites would be no problems when they arrived in my apiaries. This would not be the case. Even though I had as well regressed my bees to small cell size, 4.9 mm.

I have been wondering since 2008 when the mite started to create problems, why they were a problem for my bees with me, but not for “my” bees with Leif? Last year I decided I had to let the fact that Leif Hjalmarsson established this apiary of his more than 2 miles from other bees affect how I designed my bee management. I want of course to get better resistance with my bees in my apiaries.

A lot of focus had to be put on avoiding reinvasion, bees picking up mites from colonies with high infestation level of mites, within my own apiaries and others within about 1.5 miles.

Better selection 2015

But the difficult circumstances for the bees last year also meant that selection pressure was stronger and it was easier to choose a good breeder, if there was any. And there were good breeders, especially colony S241 which I have mentioned in an earlier blog post, but also C243. I introduced many new queens in my colonies last year, especially from S241. I had only found one mite in S241 in the brood when I tried to found out the VSH degree. And that mite had no offspring.

1. Project 1, 3 miles from other bees in a forested area started in autumn 2014. I had not treated the colonies in this project in that autumn when the project apiary was established. During 2015 I treated a couple of colonies when they showed crippled winged bees. The varroa level was not alarmingly high, so virus effects came early in infestation. Evidently reinvasion from the colonies with DWV didn’t occur very much to the other colonies in the project apiary, as in autumn 2015 varroa level was low in all colonies. Varroa level was also very low this spring 2016, and so it is now late in summer 2016.

Bee shaker1 The Bee Shaker is a valuable tool in getting a quick and easy figure of the Varroa level in the bee colonies in an apiary. Type in the search box: Bee Shaker – at the top of this blog, and you will find more info about it.

2. Project 2 started late summer 2015 as I treated all colonies in an apiary 1.5 miles from other bees of mine with an effective pesticide/miticide in August that year (I hated to do use it), to mimic somewhat how the apiary of Hjalmarsson was established. The varroa level now in August 2016 was surprisingly low, almost not detectable. It was in this apiary I had planned to reduce Varroa level by removing all capped brood frames twice with a week in between, in those colonies showing higher Varroa level than 3%. The highest level now in August was 0.3%.

Bee shaker2 The Bee Shaker will help you to decide if any colonies has to be removed (or any other action taken) from your apiary in which you are developing the Varroa resistance in your bees. It’s a simple and quick method, but you kill 300 bees. That is though nothing compared to numerous bees dying if you do nothing. Viruses and mites killing thousands of bees besides the normal die offs from worn out bees in their daily work, where tens of thousands of bees are dying.

3. Those colonies I decided last year I would shift queens in this year, I treated with thymol in April/May this spring even if they showed no signs of Varroa or virus symptoms. With this I think I secured that those colonies wouldn’t produce mites that could reinvade the other colonies in the apiary. These kind of apiaries are the most numerous of mine. I have not checked the varroa level in all colonies spring and late summer in these apiaries.

Up til now in late August 2016 I have found this odd colony in just a few apiaries, showing one wingless bee. I have tested those colonies with the bee shaker for the Varroa level and only found a few colonies with a Varroa level higher than 3 %.

In one apiary I had this colony with a decreasing varroa level during the season. Three weeks after the early August measurement with just above 1 % Varroa level, I made a new measurement. Now it showed 5 %! Too many mites for the colony to have produced it during these three weeks. Less than a mile away there is another beekeeper, with Elgon bees, but not selected for Varroa resistance for some years. No wingless bees. The colony had probably picked up the many mites from one of his colonies. I didn’t treat, but gave it a sticky board on the bottom to check the natural downfall. And a new Varroa level check will be done in a month. Hopefully this colony will be able to reduce the Varroa level. We’ll see.

An apiary at the edge

Let’s look at one apiary at the edge of “my” Elgon area. With that I mean that drones from other beekeepers’ bees can influence the matings of virgin queens. Also the risk of reinvasion is of course higher. Last year was of course not only difficult for my bees but also for the bees of other beekeepers. In this apiary I treated two colonies quite a lot last year, and also this spring and shifted their queens. The other colonies in this apiary has not been treated this year. But they were all treated last year with Thymol. Now in August I saw a bee that looked like it had the beginning of wings being crippled in one of those colonies. So I tested the Varroa level, 4 mites in 350 bees = 1.1 % Varroa level. It got no treatment of course. Very pleasing result.

A couple of small apiaries

I have a couple of small apiaries in which I checked all colonies with the Bee shaker in spring this year, 0 or a couple of mites in 300 bees. No colonies treated this spring as I didn’t plan to shift any queens this year. I had shifted some last year. I checked these apiaries now in August.

In one of the small apiaries with two colonies and a split I found 4 mites in one of the big colonies and 32 (!) in 300 bees in the other. This was too many in the later colony for it to be able to produce them by itself. No crippled winged bees. Also a sign of that those mites were picked up from somewhere else. This colony had a history of needing Thymol every year, so I chose to treat with Thymol and am planning to finally shift the queen next year. 500 meter away is double the amount of hives of another beekeeper (with Elgon bees which were not from my selection in recent years). He had had problems with one of his colonies.

The situation in the other small apiary will be described later in a blogg post of its own.

Avoid reinvasion when bees adapt

The conclusion is that it’s very important to avoid reinvasion of mites when your bees are developing their ability to control the Varroa mites. They need mites to do that, but no or few extra mites from other colnies that makes it more difficult for them to survive.

On the other hand can the explanation for the better varroa resistance with my bees, as it seems, partly be explained by the fact that I shifted quite some queens last year to S241-daughters. Bess from their colonies will drift somewhat into other colonies, as bees from all colonies do. In this case these drifted bees may well help controlling the Varroa level and possibly also teaching the original bees of the colony to fight mites better.

Genetics is of course important when bees adapt, changes in the composition of the DNA. Selection by culling the worst and multiplying the best. But bees adapt too quickly for the genetic changes to explain in all. Epigentic changes is of uttermost importance here, changes how the existing DNA is expressed, how it’s used. It’s impossible to explain the resistance developing in S. America and S. Africa in about 5 years in any other way. As epigenetic changes occur when environmental changes act upon the chemical environment closest to the bees. The precense of the Varroa causes chemical changes in the bees, in the brood cells, etc. These epigenetical changes are inherited to next generations until new environmental changes cause other epigenetical changes. We understand that chemical help against Varroa will hinder the bees’ own control mechanisms to develop fully. There will be a balance act of avoiding all kinds of miticides as much as possible without letting the bee colonies die. Avoiding reinvasion will be very important then helping the bees developing their control mechanisms fully.

As was pointed out in a previous blog post, my bees are held on small cells, which may contribute to the very low overall mite level. The mite level in Leif Hjalmarsson’s apiary he didn’t treat for many years was at least in the beginning when we measured substantially higher. He used large cells.

I’m convinced that when the bees have learnt how to control mites effectively they can handle reinavsion of mites as well, maybe also in larger numbers. I would call that VISH (Varroa Intruder Sensitive Hygiene.:)) I suspect this can take some years. Then they probably sometimes need some reinvasion to keep their skill at a high level.

Small cell size important in breeding Varroa resistance

After reading the blogpost ”Breakthrough?” an European PhD-Scientist wrote me an email with the following comment:

After reading your post I realized that you do have small cell size, but you’re not mentioning it in the actual post. To make sure that the reader’s get the full picture, the main components of your management system, this should be explained for them.

For instance, for me it’s a fact, that the cellsize used in a selection program is a factor incorporated in the population just like springfeeding appears to create a dependency of that feed to make bees start an explosive spring behavior.

As our bees are still wild animals, you can select whatever you like (or forget to see as selection-factor) to specialize your bees. Feel very good that your selection works.

But looking at the picture I have, some more ’vitality’ comes with better Varroa control. More or less ’Race’-independent. Question for me: ’slight inbreeding effect’?”

A valuable comment which gives food for thought. Thanks!

Small cell size (SC) is so natural for me, that it’s the normal thing. I forget it sometimes. Those small quick bees flying directly into the entrance are what I expect when looking at a bee colony.

It’s interesting Eric Erickson in Tucson when he started his breeding project for Varroa resistance found that many survivors that he used in his program were on 5.1 mm cell size. This was quite smaller than the most common 5.4 mm. http://www.elgon.es/diary/?p=457

Eric_EricksonF Eric Erickson when I and Hans-Otto Johnsen visited him and Lenard Hines about ten years ago talking Varroa resistance.

Erickson is said to have been forced to retire earlier than he should have. He died earlier this year (2016) well above his 70th year. There were nice obituaries, but I couldn’t find a word about his Varroa resistance program. Strange.

Every spring since I started to take my bees down to small cell size, when I took care of the dead outs after winter I saw that many combs were poorly drawn. The bees had many times failed to follow the 4.9-pattern and drawn patches of sometimes bigger worker cells and sometimes a lot of drone cells. Also when managing struggling colonies during the season the same observation was many times made. This year very little of this was seen. But I still have some colonies that can’t follow the 4.9 pattern when drawing their own combs (but they do well on already drawn small cell combs, especially colonies with heritage from queens from other beekeepers I have found interesting to try.

At the same time I’m aware that there are beekeepers that havn’t treated against Varroa for many years that still use large cell sizes. I draw he conclusion that it is possible to keep bees on large cell size and still be treatment free. But I see very little reason for not going down in cell size. The most important reason is that the bees themselves go smaller when given the chance. It must have something to do with their fitness and survival, not actually in first place in relation to Varroa.

Concerning the earlier blog post “Breakthrough?” and that I have used very little Thymol this year. Last year at the end of July I had used Thymol on about 70% of the colonies. This year at the same time of the year I have used Thymol on 2 colonies out of about 150 (I had about 150 last year too). I find it hard to believe that the only reason would be a successful breeder queen. I think better pollen availability this year has given a better immune system. And reinvasion I think is less problematic. With the latter in mind, I can imagine that adaptation to better control the mites is developing in the bees. And the absence of chemicals, in this case thymol, do not disturb this adaptation.

Another change in management is that I don’t move bees between apiaries. When making splits they stay in the same apiary. If there’s only one colony in a yard I split that colony and build up the apiary again this way (from now on). Some minor movements of bees have been done though.

Breakthrough?

Last year I saw more wingless bees than I had expected and I used more thymol than I had expected. I realized that I could partially thank the bad weather fort thias. The bees had got too little of pollen. Their immune system was not at its peak.
It was not easy to find suitable breeder queens, ie, who showed great varroa resistance. I found a colony that had not needed varroa treatment for a few years and it had not had any wingless bees. VSH test could not be done as I found only one mite in more than 100 pupae. And this mite had no offspring. So if you would allow it to determine the VSH-level, this would be 100% VSH. However, the so-called statistical significance was non-existent because of the low number of mites (just one single one). Well, the low number of mites were decisive. S241 was last year’s most important breeder colony.
This summer, I have not seen much of mites and almost no wingless bees so far. Some odd mites in 4 colonies, of more than 140 hives. Well, those who got the most thymol last year, got Thymol in May this year and then got its Queen replaced. So that’s one explanation, about 15 colonies. A colony that was a split from one of those 15, which raised a queen of their own was the first. Due to it’s history it got Thymol as soon as I saw the wingless bee. The queen will be shifted.

A problem hive had got a daughter of S241 last year. A Beeshaker test though showed 0% varroa level. Viruses still a problem in spite of no mites? 

The other day I saw a wingless bee on the hard board in front of the entrance of a colony that had got a lot of Thymol last year. It did not get Thymol in May as it was shifting its queen in May, I found a dead virgin on the hard board and drew that conclusion. I decided to make a test with the Bee shaker due to the wingless bee. I did it yesterday, July 20, 19 mites out of minimum 300 bees , 6.3% varroa level. The hive got Thymol.

1DWV 19 mites, 6.3% Varroa level – Thymol.

Today I came to an apiary with a daughter of the 241 (introduced in 2015) which have had no need for Varroa treatment in a couple of years, neither 2014 nor 2015. This colony was now a strong colony that given a good crop. With still some time to go for eventual more honey to come.

241d No need for treatment for a couple of years (2014 and 2015) plus probably this year. Actually lower Varroa level now compared with spring ( at least not bigger).

In May, I tested interesting candidates for being breeders with the Bee shaker. This 241-daughter was among those of course. The Varroa level was 2%. I didn’t give it Thymol as this was not more than 3%. I had several colonies, including several 241-daughters, that got only a few grams of thymol in spring 2015, which showed no mites at all (zero) out of more than 300 bees. The two best with different heritage (one was a 241-daughter) I used as breeders this year.

1% 4 mites, 1,3% Varroa level now.

2% -colony I tested today July 21 regarding the Varroa level, 4 mites out of a little more than 300 bees. 1.3% infestation level. At least not higher Varroa level after 2.5 months. A strong hive that has given a good crop. The Varroa level would have been much higher if the bees could not get rid of mites themselves. This colony has thus been able to get rid of mites by themselves. What a great feeling!
Now this does probably not only depend on the queen. It was introduced to a colony that had not needed any treatment for at least a year. The worker bees might have learned the new queen’s bees some tricks how to deal with mites. It would not surprise me if there is a combination of reasons for the mite fighting ability of this colony. http://www.elgon.es/diary/?p=880 http://www.elgon.es/diary/?p=890

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

Wingless bees and varroa level

Before varroan came there could be seen occasional bees with undeveloped/deformed wings in spring. Maybe it was the influence of DWV, Deformed Wing Virus. But it may also have been chilled brood. During the final phase of the pupa development to finished bee the wings are formed. Cold nights and too much of brood could maybe have caused undeveloped wings.

Today, one can probably assume that when you see a wingless bee, it’s DWV responsible. Varroa mites are paving the way for many viruses into pupae and adult bees that had not previously bothered bees. Moreover, these viruses multiply in mites. So today mites spread viruses more efficiently than when the mite had just arrived in Europe. Why that is so is another interesting discussion that probably involves the use of miticides.

 

The Bee Shaker

The Bee Shaker is a great way to keep track of the level of mites in the bee colony, especially in spring and late summer, so the amount of virus can be kept reasonably low by allowing people to fight the mite if it exceeds a certain degree of infestation. (If that is the strategy chosen.) A good benchmark that many use today is 3%, three mites on one hundred bees (9 mites in 300 bees/1 deciliter of bees).

It also means that to develop a bee stock towards better varroa resistance, you don’t treat against the mite, especially below a mite level of 3%, whenever in the season it is measured.

But if there are wingless bees in the bee colony? It’s usually a sign of DWV and thus too many mites. Here is the Bee Shaker again a good tool, to find out if there really is a high degree of infestation of mites when you see a wingless bee. If you decide to treat against mites if the level is high you might do it to prevent the spread of mites to other colonies nearby.

 

A colony with a wingless bee

Last year’s breeder queens seem to have produced many queens that have given colonies that control the mites quite well. One of these daughter queens was introduced to a colony that had problems with mites. Perhaps the biggest problem was virus.

This colony was quite weak in this spring and developed slowly, compared to the other colonies in the apiary. I concluded that I would have to check the brood nest to find out the cause. Maybe the colony was shifting their queen?

On a later visit to the apiary about June 20, I saw one, only one, wingless live bee on the hard board in front of the entrance. I then looked in the brood nest, but saw no more wingless bees on the brood frames. But the brood frames had a so called shot gun pattern with a lot of “holes” where you would have expected capped brood as the other cells on the comb contained capped brood. Many pupae seemed to have been removed by the bees. Most likely not due to inbreeding as the queen had mated in the apiary and the number Elgon colonies in the neighborhood was quite high. No trace of any brood disease could be seen so I concluded that a likely cause could be cleaning out of varroa-infested brood. Or could the bees detect virus in the pupae and remove it, without there being a mite in the cell, and remove the pupae?

Could that be the reason why the colony developed so slowly – that the bees were throwing out mites? How had they managed? The wingless bee could indicate that they had not done so well and that the amount of mites was big. Now it was time for a Bee Shaker test to find out the level of Varroa infestation. (Here you can read more about The Bee Shaker, its uses and possibilities: http://www.elgon.es/diary/?p=809)

Here you can see a video clip when doing this test (sorry I’m talking my mother tounge Swedish):

The sample showed zero (0) mites! Then it’s no use to treat, There were far too few mites in the colony. Why had there been a wingless bee recently before the test?

VarroaVirus The brood frames looked less spotty and the colony stronger.

July 8 I was visiting the apiary again. Once again I saw a wingless bee on the hardboard. But now I knew the Varroa level was low. Still no use treating. I looked in the brood nest. The colony was a little stronger still and the brood frames had fewer “holes”. The bees look healthy. They were recovering.

Virus apparently remain in the colony for a while after mites are eradicated – by the beekeeper or the bees.

A good pdf-editor I like; maybe you need one too

I’ve been working with computers, Mac and PC, for many years, using them for making journals among other things, using graphic, photo and layout applications primarily. This blog though is dealing with beekeeping issues and normally nothing else. But I’ll make an exception this time.

I and a former colleague with my former employer have made a revision of a book of 350 pages in Swedish about beekeeping, Boken om biodling (The Book about Beekeeping). I helped trying to fix a proper way of updating the pdf printing file for the book.

The original layout file was made with Adobes InDesign. But that file wasn’t available. Only the pdf printing file. We thought that Adobes application Acrobat would do the job.

Some of the fonts in the pdf-file were present in our computers, some were not. Acrobat reflow the text in several places even with the fonts present in the computer, making the text longer. This would make the job unnecessarily laborious. And the fonts not present on the computer made the problem still worse.

I began searching for alternatives and found some, mostly for Windows but also for Mac. Everyone of them had drawbacks when it came to editing the text and/or changing pictures or pricing. It’s common today with pdf type of files. And from time to time it will be a need for small or bigger changes in such a file. I want to give a good alternative. It’s not free, but it’s the best I’ve tried for editing pdf-files, taken in account the different pro and cons.

This application does the job easily, Infix Pro (http://www.iceni.com/). Works with both Mac and PC. It’s like working in a layout application.. Even if the font isn’t on the computer Infix does the job nicely anyway. If you want to replace an inbedded font which is not present on the computer to one that is, it’s easily done, on all places in the document at the same time.

You easily connect text on different pages which all belongs to the same article. This makes the text reflow nicely when needed. You can easily replace or place new pictures. And Iceni has a very good support team which helps you quick eough when you need help.

Struggles for the survival of honey bees

S SB

SB is a relatively new and dedicated beekeeper in southern Germany. She is interested in different kinds of bees and their place in the ecological system. I asked her to tell her story and her struggles helping her bees to survive and thrive on their own as much as possible without chemicals. She writes:

After watching wild bees for some years I wanted to have honeybees and took lessons given by an organic beekeeper. In the year 2014 I bought my first colony from him. It was a Carnica cross on natural comb, built by the bees without the help of wax foundation. They had been treated with oxalic and formic acid against the varroa. But they were sick anyway!

S Natural comb My first colony was a Carnica (Carniolan) colony on natural comb.

I tried to find a way out of this chemical strategy that seemingly didn’t help. I got some information on internet and started watching how bees defend themselves against illnesses. I don’t want to have them close to other bees. I tried to help them with sugar powder dusting to rid them of the mites sitting on bees. After treatment with formic acid in summer, they had a natural downfall of 30 mites per day. After sugaring the whole hive ten times with 2 days in between the natural downfall of mites were 5 per day. This involved a lot of work and still didn’t do the job. The bees had chalk brood too!

I measured cell size on their natural comb. It was 5.0 mm in the brood area, 5.4 in food area and drone cells began at 5.6. All honey was taken when harvested, so they lived on sugar syrup for a long time of the year. They died in february 2015, not having enough bees to warm the hive!

S AMM queen The AMM queen

I had found some contacts through internet and was able to get 4 hives in 2015 which weren`t treated with chemicals for some years. One was of the dark bee Apis mellifera mellifera (AMM) , three were Carnica (Carniolans). I made some splits and wintered 3 of the AMM origin and 5 of the Carnica origin.

The former owner had a crisis being the victim of a migratory beekeeper whose hives most probably caused reinfestation bringing a lot of mites into his hives. He overcame this crisis combining the weakest of his hives, so they became strong enough to defend themselves. Some survived. In some of these he introduced a AMM variety of queens that had a reputation of being more resistant.

My aim was to follow Dee Lusby`s in Arizona way of beekeeping as much as possible (http://beesource.com/point-of-view/dee-lusby). Using small cell foundation, leaving with the bees enough honey for food, using so called housel position of the combs, what she calls unlimited broodnest and using no treatment (if possible).

S Carnicas Now I have 11 colonies and high hopes.

All 8 hives survived winter, but in spring 2016 I had to eliminate one of them because its bees were too susceptible to virus (another than DWV). I have made some splits and have now in May 11 hives and high hopes. The bees are my teachers. I want them to survive.

S hygienic The AMM I have are showing hygienic behaviour against mites in the brood. Now I have seen it also in my Carniolan crossings (the picture).

I don’t do drone brood cutting as I want the mite to continue being a drone parasite in first place and not a worker bee parasite. I’m happy to see more and more of hygienic behavior against the mite, also in drone brood. Now also in the Carniolan crossings.

At last I want to quote Kirk Webster (http://kirkwebster.com):

“Beekeeping now has the dubious honor of becoming the first part of our system of industrial agriculture to actually fall apart. Let’s stop pretending that something else is going on. We no longer have enough bees to pollinate our crops. Each time the bees go through a downturn, we respond by making things more stressful for them, rather than less – we move them around more often, expose them to still more toxic substances, or fill the equipment up again with more untested and poorly adapted stock. We blame the weather, the mites, the markets, new diseases, consumers, the Chinese, the Germans, the (fill in your favorite scapegoat), other beekeepers, the packers, the scientific community, the price of gas, global warming – anything rather than face up to what’s really happening. We are losing the ability to take care of living things.”

We are at big risk losing the ability to take care of living things. Thank you everyone who is helping me to improve myself as a beekeeper.