Category Archives: Cellsize

Darwinian beekeeping, cell size and fitness

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I respect and appreciate Tom Seeley and consider him a friend. He coined the expression Darwinian beekeeping. He has given us deeper understanding of the natural bee colony. But I don’t understand an expression of his in one of his lectures in London Honey Show in 2011:

I don’t understand why beekeepers are so interested in small cells.

There are scientists that have expressed suspicion, yes even an opposition towards small cells (4.7mm – 5.0mm, large cells 5.2-5.5, extra large 5.6-5.8, average 5.1). Tests have been done with small cells. Focus has been on reproduction of the varroa mite. None of them has come with the result that small cells are bad for bees. The majority of them are expressing a result that is not statistically significant concerning a good influence on varroa resistance. But there are tests that show a positive impact on the varroa level, for example this: http://www.elgon.es/norwegian_celltest.html. Concerning the design of tests please read this analysis: http://www.elgon.es/testdesign.html

 The classic picture by Dennis Murrell of a top bar with diffferent cell sizes. Those to the left are close to the entrance. An advantage with naturally built combs is that the midrib of the comb is very thin compared to a wax foundation. Therefore it’s easier for the bees to tear down combs and rebuild them as their needs changes. When a swarm starts to build combs they often start to build cells 5.3 mm big as their first need is to store the honey they are carrying in their honey stomach. Often they build quite some drone comb too. If it’s a first swarm and the queen is old they may well replace and then they need drones. Later when the nest is growing they replace some combs with new and build more honey storage away from the entrance (information from Johan Ingjald in Sweden who has studied this in his colonies).

Natural cellsizes

When bees choose themselves, what cellsize do they make? They make a range of cell sizes. When we look at naturally built combs in colonies where wax foundation is not used, the brown (or black) wax, that’s wax in which there have been brood, the range of sizes is smaller than in areas where you find wax in which there have been no brood. In such areas bees store honey. See the picture of the top bar comb taken by Dennis Murrell.

What did bees build before wax foundation was used? Wax foundation started to be used more widely after the introduction of the waxroller mill in 1876 by A. I. Root in America (cell size 5.1mm, which was said to be the average of cellsizes in a colony). See the article about cell size history: http://www.elgon.es/naturalcellsize.html

The conclusion is that nature favors small cells in the brood area and larger in the honey storage area. After a thorough investigation the Harvard professor Jeffries Wyman published the result 1866 to be 4.7 mm – 5.3 mm for the cell sizes. The British scientist Thomas W Cowan replicated his test 1890 and got the result 4.7 – 5.4 mm.

Natural selection and fitness

Natural selection (adaptation) is what nature uses to adapt creatures to their environment. It’s one of the forces in the Darwinian theory (the theory of evolution). Sometimes this is called survival of the fittest. This includes not only survival, but those individuals that survive, are healthy, strong and not the least reproduce most efficiently.

The answer why bees want mostly (but not only actually) small cells in the brood area is obvious, isn’t it? The bee colony then is then better fit, survive better, is healthier, stronger and reproduce better. The question is not in first place about varroa resistance, it’s about fitness!

The result would be lower annual losses of bee colonies, whatever the reasons for the losses may be: pathogenes, bad managemant, chemicals, etc, wouldn’t it? The varroa mites don’t kill the bee colony by themselves, but through ”cooperation” with viruses.

There is a project presented in the Swedish beekeeping magazine – Bitidningen 2018, no 3 – called ”Varroaprojekt LEKA” (perfomed during autumn 2014 to fall 2017). It supports the conclusion that small cells in the brood area gives better fitness. A report of it may show up here on this blog.

Initially when varroa mites arrive to an area the mite population can become very big, regardless of the cell size in the brood area. If the bee colony does not die of viruses (it must be interesting to find out why that can happen!) it will adapt and lower the mite level with the help of different traits strengthened through adaptation processes (epigenetic and genetic), with the help of natural selection. See: http://www.elgon.es/diary/?p=1121

In the light of the above:

I don’t understand why scientists are not more interested in small cells.

There are more reasons for losses than large cells in the brood area. But why not minimize one obvious cause for bad fitness that we can do something about?

In Sweden the standard cell size now in practise is 5.1 mm. The use of 4.9 mm is increasing, 5.3 is diminishing. In Norway the situation is somewhat similar.

Varroa resistant bees

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– African bees are resistant to Varroa mites, or become resistant in about 5 years after the mite has come to their hives, in Africa and Americas

– Italian bees on an isolated island close to the cost of Brazil have showed resistance in the same way as Africanized bees in Brazil. But the varroa level has decreased slower.

– The original host of the Varroa mite, Apis Cerana, is resistant to the mite and is very similar to Apis mellifera (African and European honeybees).

– My Elgon stock is selected for varroa resistance since more than 20 years.

• When reinvasion sources are few or none.

• When varroa levels are tested regularely.

• When bee colonies are treated when the varroa level is above 3%.

• When queens in such colonies are replaced –

• Then Elgon bees in my area seems to become resistant.

 

AHB1, Africanized Honey Bees

Africanized honey bee . Photo: Jeffrey W. Lotz, Florida/Wikipedia 

 

Remy Vandame describes in this doctorate thesis in 1996 that he found the varroa level on worker bees to be 5%. And more than 3000 mites in total.

That figure is about the same as in another study in which Vandame also was involved in Mexico some years later.

The AHB colonies were not alone in the test apiary. European queens (EHB) crossed with AHB drones in a number of colonies were in the same area. Those had better performance concerning varroa infestation and virus problems compared to EHB in USA or Europe, but not as good as the AHB. Drifting and silent robbery during nectar droughts are strongly suspected to have happened, thus evening out the results somewhat.

In December 1991 in Brazil, AHB bees were reported to have a varroa level of 4% (ABJ Oct 1997)

 

EHB on Fernando de Norhona, outside the coast of Brazil

European honey bee (probably not on small cell). Photo: Wikipedia/Luc Viatour/https://Lucnix.be 

 

Italian bees on a small island at the coast of Brazil (latitude south 22°) has the same small amount of DWV as in honey bee colonies before the arrival of the Varroa mite. This virus seems to be the most dangerous virus connected with the Varroa mite. (DOI: 10.1038/srep45953)

In 1984 africanized colonies without queens were brought to the island. They were made into 20 colonies in which queens reared from 5 selected Italian colonies from California were inseminated with drones from a colony from Georgia, USA.

The number of managed colonies was at the most about 50, today maybe 30. Besides numerous feral colonies that together with the managed colonies form the bee population on Fernando de Norhona.

  • In November 1991 11 colonies were examined for varroa varroa level. In three of these about every second bee had a mite (50%). Average was 26%. Lowest about 9%.
  • In April 1993 more colonies were examined. Highest varroa level 39%, average 19%, lowest about 9%.
  • In May 1996 of those examined the highest was 25%, average 14%, lowest about 9%. No damaged colonies, no virus effects. Good producers, very nice bees. (ABJ Oct 1997)
  • In November 2012 the varroa level was found to be about the same as in May 1996, about 14%. (DOI: 10.1007/s13592-016-0439-5)
  • In May 2016 the varroa level was 1-2%. Mites in brood also lower compared to November 2012. (DOI: 10.1038/srep45953) Has the time of the year significance concerning the Varroa level on the island, as it has in other areas of the world. It is lowest in “autumn” whenever that is. Here it seems to be in April-May, with lowest Varroa level then. Highest Varroa level in Nov-Dec. Maybe the lowest and highest months are somewhat different. No one seems to have measured to find out yet. Then it’s most logical to compare the figures from Nov 1991 with Nov 2012 and April 1993 with May 1996 and May 2016.

One thing is evident, the bee and mite populations are isolated from reinvasion from outside.

No chemicals to fight mites and big agricultural crops are used, that can contaminate the colonies or lower the immune and defense systems of the bees.

Cell size (about 4.9 mm) from the beginning anyway was that of the Africanized colonies brought there.

The Africanized microfauna came with them as well. The first brood was nursed by healthy non-contaminated small bees that helped the new queens to epigenetically adapt to the new environment.

 

AHB2, African Honey Bees

African bee in South Africa. Photo: JMK/Wikipedia

 

When mites arrived in South Africa you could find colonies with huge amounts of Varroa, up to 50,000. No reports of big losses due to the mite were given, if any. In about 5 years both the Cape bee (mellifera capensis) a little quicker than 5 years and the Savannah bee (mellifera scutellata) a little slower were found resistant to the Varroa mite (Mike Allsop doctorate thesis 2006).

Today (2014) the varroa levels are low, and no miticides are used to control the mite. In May, which is autumn the average varroa level was about 2%. In spring, September, it was about 1.5%.

Total varroapopulation in average was in May just below 1000 and in September just below 200 mites. No DWV (Deformed Wing Virus) was found. DOI 10.1007/s10493-014-9842-7

No miticide chemicals are used or were used (more than a ittle in the beginning of the arrival).

No bees full of viruses are spreading DWV.

Cellsize is 4.7-4.8 mm.

 

EHB in my Elgon apiaries

Click on the picture to get it larger. My testapiary for small cell Elgon bees Dec 1, 2017.

 

In autumn 2014 three colonies were brought from an environment with higher mite populations in some colonies within 2 km to an isolated test apiary, at least 3 km (2 miles) to other bees. None were treated in 2014 and no DWV-bees were observed.

One colony was weak in spring 2015 and got one thymol pad (5 gr thymol). Two splits were made in 2015. In late June three colonies showed crippled winged bees (DWV). They hade varroa levels of 2, 3 and 7% and were treated with thymol pads. One colony with 3% varroa level showed no DWV and wasn’t treated. In August 2015 the Varroa levels were 0, 0,3, 0,3 0,3 and 3%. One weak colony that got a laying queen introduced late in the season died during the winter.

Two spits were made in 2016, one were made in 2017. 2017 was the third unusually bad year in a row and the apiary is placed in a forested area with low nectar resources.

Varroa levels in average during 2016 was 0-1,5%, during 2017 0-1%.

No treatment were used 2016 and 2017.

Cellsize 4.9 mm – http://www.elgon.es/resistancebreeding.html – Strategy A. Isolated apiary, treat above 3 % varroa level.

 

Resistance breeding in an environment with high virus pressure

In most western countries we have a high varroa and virus pressure. Probably the result of heavy use of treating the colonies against mites for many years. In the light of what varroa levels finally stops at naturally, according to the above experiences, 1-4%, and the experiences I have had the latest years with treating colonies with varroa levels above 3% and replacing the least good queens – I find this strategy a good solution to get varroa resistant bees in even difficult environments.

It may probably take a little longer if the new queens will mate with more than a few drones from susceptible colonies. But that doesn’t matter to much as a queen mates with in average 20 drones. The bad genetics will be weeded out quite quickly if you are keen in replacing the least good queens every year. 

Reed more on this link: http://www.elgon.es/resistancebreeding.html

Resistance traits – VSH, VSHD, Grooming and more

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Sometimes, the term VSH is used as meaning the same thing as varroa resistance. I think it’s helpful to clarify what VSH is. It is one of several resistance characteristics that affect the bees’ resistance to the Varroa mite.

VSH is not the same as uncapping capped brood cells with varroa inside and remove the pupae. It is one of a few different varieties of cleaning varroa invaded brood cells.

– VSH is opening (+ possible recapping, and / or + possible removing the pupae) of capped workerbee brood cells (not dronebrood cells) in which one or more varroa mites have entered AND the presence of offspring (children) to this (these) varroa mite(s) in these cells.

 VSH

As we see from the description here there could be different varieties of this trait. It isn’t needed that the bees remove the pupa for this behavior to de called VSH. It is enough that they uncap pupae with invaded mites with offspring. The bees may well recap it again. Uncapping is enough to disturb the reproduction of the mite. Is this difference in behaviour (recapping the cell and not removing the pupa) due to genetic difference?

– Uncapping and cleaning of capped workersbrood cells with varroa which have no descendants is not VSH.

– Uncapping and cleaning of dronebrood with varroa is not VSH. (But this is though also a valuable feature.)

– Other properties like grooming (removal and biting of mites from the body of other bees or themselves is an important feature, especially if the colony is reinvaded by mites.

– Resistance to viruses, for example in the form of good production of suitable peptides (short amino acid strings) which “eat” viruses is important.

– Reduced inclination for robbery is not VSH, but is a good feature, as it means less risk for reinvading/reinvasion of mites from bee colonies with increased varroa level and as a consequence thereof a reduced defense against robbery.

– Good defense at the entrance not letting foreign bees enter the hive prevents bees with mites on them from other colonies to raise the varroa level..

– Bees that return to their own hive and not to the neighbor’s (drifting) is an important feature to prevent the spread of mites within the apiary.

– Forcing virus infected bees to leave the hive is one way for the hive to get rid of viruses, it’s not VSH, still very good. The house cleaning bees treat virus infects bees like trash, bees with damaged wings (DWV) or worker bees hatched too early (grey bees crawling around, APV-types).

– There are I’m sure more traits that are important for resistance.

 

VSH is a good feature!

VSH can sometimes be confused with less good development for a bee colony. This depends most often on a queen not laying eggs very well. But if a VSH colony is getting a lot of mites through reinvasion from colonies with high varroa levels in the neighborhood (within a distance of 2 km/1.5 miles) the result may be a lot of shotgun pattern brood combs due to a lot of uncapped and cleaned brood cells to get rid of mites. The consequence will be a slower development of the colony. But as mentioned above a true VSH trait give room for the variety that the pupae are not removed but they are recapped after uncapping. And this can happen more than once. In such a case the consequence needn’t be slow development of the colony even if the varroa level temporarily is a bit high.

This is a good example of VSHD. You see clearly that pupae in drone brood are removed as brown cocoon residues are left. This is the first round with brood. Also we see uncapped drone pupae with purple eyes, and some cells with uncapping having started with holes in the capping. Click on the pictures to make it bigger

 

 More acronyms

Perhaps it’s good if more short names, such as acronyms as VSH, become common, names for different characteristics of resistance.

– With regard to the concept of Grooming, This term is well established. Bees have mites on their body and these are removed by other bees or themselves. We need no other term here.

– As far as VSH on drone is concerned, it is quite newly discovered and no special acronym is used as far as I know. VSHD = Varroa Sensitive Hygiene Drones.

That’s an important feature, maybe more important than VSH. The acronym VSHD could work well.

The mites are more attracted to dronebrood than to workerbrood. If a colony has 5-10% dronebrood in the brood area, as is often found in feral colonies (at least) and bees have a strong VSHD, the bee colony will not lose so many worker pupea (future valuable worker bees). Many mites will invade drone brood and will be cleaned out from this drone brood.

The Norwegian Hans-Otto Johnsen has shown (he is conducting such surveys and there is some notes about this in Norwegian bee magazine Birøkteren and on this blog) that bees more easily identifie mites in smaller dronebrood cells (6.2 mm) than in larger (7.2 mm), and clean out them from mites and pupae. Bees make smaller dronebrood cells naturally, the smaller the cell size is for workerbee cells. This is probably an important characteristic that small cell size provide. The drone cellsize is naturally 6.2-6.4 mm when the bees live on 4.9 mm worker bee cells.

These acronyms may work

– ED  for entrance defense.

– LR  for low robbery.

– LD  low drifting.

– VP  for virus peptides.

– VB  for trashing virus infected bees

– If you have suggestions or comments don’t hesitate to share them, for example concerning more resistant traits. Maybe you have ideas how to measure resistance traits? Maybe the best selective tool is just measuring the varroa level a few times a year?

Treatment free focus in Germany

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 Besides detecting mites in brood and clean them from there, grooming mites from each other and bite them is also an important trait for bees fighting mites. Here a mite that has got some legs bitten. It will soon die after such treatment.

Treatment free focus in beekeeping is a growing movement in Germany, like in many other countries. This can be done in harmony with the legislation in almost all countries, if not all. Most legislations require treatment against the varroa mite, so people have come to think that they must treat every year to follow the law.

Now many have discovered that prophylactic treatment (before it’s actually needed) is almost never required, if anywhere. This means that to be able to be treatment free and keeping the law, you need to monitor the varroa level. If it’s below the threshold level, the mites create no problem for your or your neighbor’s bees, and no treatment is needed (yet?). The threshold level recommended by authorities is today in a climate similar to ours (Canada) 2% (two mites on 100 bees) in May and 3% in August. http://www.omafra.gov.on.ca/english/food/inspection/bees/varroa-sampling.htm An IPM PP-presentation from the university of Delaware: http://alturl.com/ed92e is focused also on developing resistant bees and management methods. You can find threshold values of 5% for the middle of the summer from universities in America, but that is probably to high for bees with weak resistance traits.

If the varroa population is above the threshold, the conclusion is that you have to take action to help the bees lowering the mite level. This can in many cases be done without treatment chemicals (drugs, essential oils or organic acids), but instead with other means. Monitoring can be done through checking natural downfall, looking for DWV bees (virus damaged bees) in front of the entrance or on brood combs, doing alcohol washes or sugar dusting. An effective treatment without chemicals – oils, acids or drugs – is removing capped brood, worker or/and drone. This of course effects the growth of the colony, but you can get a much worse effect by doing nothing at all. Also making artificial swarms is a way of preventing mite growths.

An important reason why you want to avoid the use treatment chemicals is that these interfere with the bees’ epigenetic adaption to rid themselves of mites.

This should be followed by replacing the queen in colonies with the worst problems with a queens bred from a more resistant colony. Also it’s important to let resistant colonies produce splits as well as a good amount of drones for the virgins to mate with.

Two beekeepers in Germany who work together according to these principles are Stefan Hutterer and Sibylle Kempf. They are active in a beekeeper group and on forums. Sibylle also makes many good comments on my blog. Here they give us reports from their season of 2017.

The story of Stefan

I´ve been keeping bees for 10 years now and decided in 2012 to regress one hive to small cell (SC) comb with the help of plastic comb (Mannlakes standard plastic comb https://www.mannlakeltd.com/shop-all-categories/hive-components/frames/plastic-frames/standard-plastic-frames ). That worked well, but the pure bred carniolans which I had could not follow the imprint of the cells on small cell wax foundation. Plus, which I think is important, they used no propolis. They were very susceptible to pests and diseases too.

The carniolan bees couldn’t follow the small cell pattern on the wax foundation and made a messy construction.

I wanted to be treatment free but I realized that in the end the only way to reach this would be to use a bee that had traits that had showed more success in this area.

2013 I ordered my first elgon queen from Josef Koller without expecting too much. I was curious how they would perform. This first Elgon colony survived winter very well and built nice 4.9 mm cellsize (SC).

A perfectly drawn SC wax foundation by an elgon colony

I think it’s important that bees do produce propolis to help them stay healthy. Here’s some applied on the top bars fo a mix of wooden and plastic frames in an elgon colony.

Mating apiary with Stefan. Apideas placed 4 and 4. Drone producing colonies in the traditional type of bee house.

I bred some daughters, thus making F1-colonies as they mated with carniolan drones and introduced them in Carniolan nucs. The more new bees that hatched in these nucs, the more they became lighter in color and less grey. I was impressed by the gentleness of the bees, and at the same time different in comparison to the carniolans as they were very defensive towards wasps and foreign bees and watched the entrances ferociously. Still, working with them was nice.

They started making brood later in spring than the carniolans, but I never had an elgon colony isolated from stores in winter or starving. They know how to househould with their food resources.

An elgon comb where the bees have uncapped cells with worker pupae as a way of fighting varroa.

2015 I got two pure bred elgons from Erik Osterlund in Sweden through a couple of friends, members of the ResistantBees Forum of Stephan Braun, La Palma. Now, 2017, I have only treatment free small cell bees except two large cell (LC) Carniolan hives.

I´m living in an area flooded with carniolans and I´m not isolated. This will not change. I also keep survivor colonies of unknown origin in my beeyards, but I know that I must propagate the best genetics to stay being treatment free.

So I breed every year from one or two pure bred elgon queens and shift all unsuccessful queens to better ones. I therefore this season bought two elgon queens directly from Sweden with the intent to use them the coming season.

Stefan Hutterer

Struggles for survival

My friend Stefan Hutterer and I started to work together and use the elgon bees because we realized they are less susceptible to diseases and are fighting more ferociously against the mites. They are more gentle than the imported Apis mellifera mellifera (AMM) we tried, and bring in more honey. These traits will hopefully convince other beekeepers to try treatment free beekeeping too.

A nice brood comb in an elgon colony.

A pure elgon queen mated with local drones giving a F1-colony.

To get elgon genetics in our beeyards, we purchase pure bred elgon queens, now directly from Sweden and breed virgins which are allowed to mate with drones of our local adapted bees, which are the carniolan crosses mostly but some buckfast combinations, and a growing number of elgons. So far the elgon crosses keep their good traits but we plan to introduce pure bred queens with not too long intervals. Stefan has kept elgons now for 3 years.

We want to flood our areas with our drones and give nucs to people working with us through our forum www.vivabiene.de

A workshop with our treatment free beekeepers group. We are producing small cell wax foundation with the help of mold parts bought from here: https://resistantbees.com/shop/index.php?id_category=7&controller=category&id_lang=5

We are trying to use foundationless naturally drawn comb to have locally produced clean wax. The elgons promptly built small cell natural comb in the brood area. The carniolans were not able to do that very well, probably because they are being bred on an unnatural cell size of 5.4 mm in the brood area for a long time.

Some members in our group will use well built small cell comb to regress the local hybridized colonies down in cellsize and try natural comb later.

I had big losses in winter 2016/2017. I went from 14 hives to 4. Four of the losses were the result of mite infestations. The others were due to bad matings and isolation of the cluster from food stores.

I went on and made splits from the survivors. Now in the autumn of 2017 I have wintered 12 hives. I got one colony from Stefan. Another one is a swarm with large cell (LC) bees I caught, which I now regress treatment free to small cells (SC) in my garden. My SC colonies are placed in apiaries with only my SC bees. Besides the LC swarm 4 are of the AMM mother line, 5 Elgons and 2 carnica crosses of survivor type.

Stefan has never had a crash. His losses are average, compared to both treatment free and treating beekeepers in his area. When he himself had both kind of bees in the past, small cell (SC) treatment free and LC treated with acids, he had about the same amount of winter losses in the two groups. Now he has changed to only SC treatment free. He is a very skilled beekeeper and has avoided some problems I have had as the inexperienced beekeeper I am, but I’m learning quickly.:)

I realized, that making strong splits with a lot of capped brood and a laying queen are “mite breeders“ in our environment, so I have tried other methods to make new colonies. This year I made small splits when doing them with laying queens and gave those only a few brood combs and some with food. Splits without an egglaying queen but with a virgin queens or a ripe queen cell were made strong. All splits got robber screens in front of the entrance to prevent robbing. When splits are placed in the same apiary as the one the bees were taken from all field bees flew back to the mother colony and left them defenseless against robbery. But the robber screens are good help against robbing.

Robber screens prevent robber bees from other colonies to interfere when introducing a new queen in a nuc or split.

May 16, I made a small split with my F1 elgon queen (pure elgon queen mated with local drones) I got in 2016. In the “middle” of the broodnest with 3 brood combs (no drone brood on those) I put a foundationless frame with just a starter strip of foundation. I was happy to see that in the middle of the comb they built naturally almost perfect small cells.

The small elgon split made small cells in the middle of a foundationless frame, which area the bees used for brood.

I have also had too much space during winter for the bees. I will change that. The bad matings were a result of the unfavorable weather situation in 2016, so I have to watch more carefully the time for breeding new queens and having them mated. There must be enough high temperature and enough amount of mature drones.

Beekeeping situations always change. To have success you must adapt to the needs of the bees and what nature tells you and develop a sensibility for this. This is hard work for me but when I see the beautiful elgon bees and the dark feral looking ones I have, the descendants of the AMM and still some carniolan crosses survivors I have, I enjoy every day learning from them.

After the colonies had been allowed to keep honey for winter stores Sibylle was able to secure a small crop for herself.

Sibylle Kempf in one of her apiaries.

The small harvest of honey I took after leaving the bees enough of their own honey for stores is a most wonderful compensation. Thank you, bees.

Sibylle Kempf, 4th season treatment free beekeeper

Varroa resistant bees in Norway

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It is positive that the research community is becoming increasingly focused on varro-resistant honeybees. The latest report comes from a doctoral student, Melissa Oddie. She has started an investigation why a Norwegian beekeeper’s population of bee colonies can be called resistant because, according to his information, he hasn’t treated his bees against varroa in at least 19 years. Their article is a pre-presentation before it is peer reviewed. It could be read and downloaded here when I was writing this: https://peerj.com/preprints/2976.pdf

The result showed that the varroa population of the test bees had a growth rate of 0.87, ie a decrease over time. While the non-resistant control colonies had a growth rate of 1.24, i.e. an increase of the mite population over time.

 

Positive details in the study

  1. One of the beekeeper’s own apiaries was used and its colonies were used in the test.. Thus, no queen was introduced to other types of bees in another place. The resistant bees and their queens were tested in their normal environment.
  2. The distance between the test and the control colonies were big, 60 km.

 

Details missing

  1. The name of the beekeeper. He had earned a place among the authors.
  2. The beekeeper has exchanged breeding material with another commercial beekeeper since 2004. This beekeeper has also not been treating his bees for many years.
  3. The number of bee colonies forming the resistant colony population is not mentioned.
  4. The cell size used by the beekeeper is 4.9 mm, ie small cellsize, for almost as many years as he did not treat against varroa.
  5. The cell size of the control colonies is also not mentioned. Is it also 4.9 mm or larger?
  6. It is not mentioned if there are other bees close to the test and control colonies. The test beekeeper has several apiaries. If any of them are near the test apiary, it would probably not affect the test. How many other type of bees could be found near the test and control apiaries (if any) is not mentioned and, if so, the distance to these bees. It is important for the reinvasion risk.
  7. Nothing is mentioned of annual losses for the years backwards for the test and control colonies. It may be of secondary significance and these figures may also not have been secured. However, some kind of data about of the losses at the beginning of the adaptation of the test bees could have been interesting to take part of. But the article is inspiring anyhow.
  8. There are also no tips for beekeepers inspired by their article to start developing their bees to become resistant. Of course, it is not a task of the test I understand, but some kind of comment about this has been positive since many beekeepers will certainly appreciate the article and be inspired by it. However, such advice I look forward to find in follow-up articles in bee magazines.

Varroa project 2014 –>

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Click on the pictures to get better quality and readability

This test is accomplished and funded by LP:s biodling bee equipement supplier, Arne Andersson sideline beekeeper and Erik Österlund sideline beekeeper.

 

GOAL FOR THE PROJECT

The goal for this test is to see if it is possible:

  • to improve mite resistance in apiaries with 5-10 colonies,
  • to understand the impact of ”isolation” of 3-5 km (3-4 miles) to other beekeepers
  • to understand the role of small cell size in the broodnest
  • to see the role of differentiated treatment of varroa mites, that is treatment of only those colonies that exceed a defined varroa level

 

PLANNED MANAGEMENT

Avoid silent robbery

The colonies should be managed as similar as possible to a beekeeper that want to increase the number of colonies with an extensive management method. It should interfere as little as possible with the bees activities and avoid disturbing parameters, which could happen when you open the colonies often, like for example starting robbing in nectar droughts. It could be enough with silent robbery, a robbery activity that you don’t notice. That could be enough to destroy a test, in that the varroa populations are evened out

3% strategy

Therefore we decided to maximize the number of hives for the two main groups in this test to 10 hives (5+5). We also decided to make two or three alcohol washes with 1 dl of bees to monitor the varroa level during the season. When the Varroa level was higher than 3% we planned to treat with thymol. If it appeared wingless bees in or in front of a hive treatment was also to be performed.

Use of thymol

We decided to use dish cloth pads drenched with fluid thymol mixed with a minimal amount of rubbing alcohol (to lower the melting point of the thymol crystals) as treatment against mites when decision was made to treat. You can see how they are done and used in this article: http://elgon.es/resistancebreeding.html

Crop and feeding

If possible a harvest should be taken and sugar solution (or honey) fed at the end of season after harvest to ensure enough food for winter. The goal should be to leave a fair amount of honey for winter, if possible as much as you think your bees have got genetics to make it through the length of your winters.

Nucs and splits

Increase are made by making so called walk away splits that remain in the same apiary as the mother colony. These are allowed make there own queens, or supplied with mature queen cells made from a good colony in the apiary. This should also be the swarm prevention method.

Elgon and Carnica/Carniolan

We choose to use two different types of bees in the project. One type that has been selected for varroa resistance during many years, Elgon, that has been bred with this purpose since 1989. Another type that hasn’t been selected less, but in other traits are good, pure bred Carnica/Carniolan bees.

 

FITNESS

Increase of the number of colonies

The number of colonies wintered each autumn would be a way to measure the difference in success between the two parts (large and small cell size) of each main group, Elgons and Carniolans. To be counted in the increase would be the colonies that are brought out from the apiaries and the project, a kind of crop. What we measure will thus be the production of new colonies and survival of colonies to the next season, the difference of fitness. If colonies survive to the next season is not only dependent on the varroa and virus levels in the colonies, but also on other circumstances that influence the survival and how a colony thrive, for example other pathogens like nosema and quality of food like pollen throughout the season.

Start and number of years

Instead of starting the project with 5+5 colonies with each type of bees, we have choosen to start from a fewer number of hives and increase the numbers. And we plan to continue the project for at least 3-4 years. We have choosen areas for the test that are low in nectar and pollen sources. That’s also a reason why the number of hives are restricted to five in each part, which makes a total maximum for each type of bees 5+5 colonies, 5 small cell and 5 large cell.

 

CARNICA

Four Carniolan colonies, all of them being sister queens from a pure bred Carnica/Carniolan stock, were divided in two groups with 30 m between the groups. These groups were placed in a deeply forested area far enough from the Elgon bees. Here it was no farm in the neighborhood, like it is where the Elgon bees are placed. One group was established on Mann Lake’s standard plastic frame, 4.95 mm cell size. The other on Anel plastic frames with 5.5 mm cell size. Frame size medium (448 x 159 m). Hive type well insulated styren plastic boxes.

The Carnica bees 2014-2015

The Carniolan queens we received in 2013 were introduced into Elgon small cell (SC) colonies on 4.9 mm cell size shallow sized frames (448 x 137 mm). The Elgons are adapted to SC during many years and if nurse bees fed and born in SC should be of importance that criterium should then be met for this test. The Carniolans in their homeland could not draw and thus live well on ”SC”. Here they were adapted immediately through this process, but they could not draw wax foundation 4.9 well even though they lived well on 4.9. Probably because they were not genetically adapted to small cells. Mann Lakes 4.9 they could draw well. Probably because of the high plastic cell wall starters which they couldn’t remodel

In 2014 half of the Carniolans got only Mann Lake’s 4.9 (SC), half got Anels 5.5 (large cell, LC). During 2014 they were this way transferred to these two types of frames. Increasing cell size in the LC-group up to 5.5 was no problem either as they were adapted to 5.5 in their genetics before they came here.

All the Carnica/Carniolan colonies were treated with thymol in 2013, but not much, and in September 2014 after they were moved to their test destination. No DWV-bees were observed in 2014.

The LC part of the Carnica bees 2015

In 2015 in June the LC-group (both colonies) showed 6% varroa level and crippled winged bees, one colony quite badly. They both got one treatment with two homemade thymol pads with about 5 gr thymol each. The LC-bees gave no crop. The Varroa level had not increased again very much and was only about 1 %.

The SC part of the Carnica bees 2015

The SC colonies had 0.3% and 1% varroa level respectively. In beginning of June a so called walk away split was made from one of the SC-colonies. The new queen then of course mated to very closely related drones.

The strongest SC-colony gave a small crop.

In September the SC-colonies still had only around 1% Varroa level. None of the colonies got any treatment in the autumn due to the low varroa levels. The SC-colonies thus got no treatment at all in 2015.

The Carnica bees 2016

The LC part of the Carnica bees 2016

The weakest of thee LC colonies didn’t make it through winter. The second one looked fine in May.

The weather was then rainy and chilly for several weeks, and when the beekeeper returned in late May to monitor varroa levels, in the remaining LC-colony he only found some dead brood and a few dead bees on the bottom.

The SC part of the Carnica bees 2016

In spring 2016 the now three SC-colonies were doing fine, two of them though small in size.

In the three SC-colonies the varroa levels were 3-4% in late May and some crippled winged bees appeared. Thymol pads were applied in June. A walk away split was made from the strongest SC-colony. The weather was unfavorable and the other three robbed the split. It thus died.

In September the three SC-colonies looked fine and got no treatment. The bees superceded the three year old queen.

The Carnica bees 2016-2017

The three SC-colonies were moved to an apiary with better resources for nectar and pollen. Some more pure bred Carnica queens were received in 2016. They will be used to biuld up the test apiaries again. Daughters will be bred from these and mated in the apiary with drones from the survivor colonies of the SC bees.

The whole season of 2016 was bad in producing nectar and pollen. The colonies had a hard time growing in size. It was late in the season when complementary feeding in preparation for winter was done that they grew somewhat in strength. That was the reason these bees were moved to a better place for food.

All three colonies actually were weaker than wanted going into winter. Two colonies made it through winter. The third and weakest died. This colony had probably survived if it had been fed honey (or fondant) and pollen during the worst nectar- and pollen drought periods.

 

ELGON

Six Elgon colonies of two different mother lines divided in two groups with 3 colonies each were set up. These groups were placed in a deeply forested area with a small farm in the neighbourhood. The two groups were placed about 700 meters from each other. One group got Mann Lake’s standard plastic frame with small cells (SC), 4.95 mm cell size. The other got Anel plastic frames with Large cells (LC), 5.5 mm.

Two sister groups were used. One sister group consisted of 4 queens, 2 SC and 2 LC. The other sister group had two queens, 1 SC and 1 LC. Frame size is medium, (448 x 159 mm). Hive type with well insulated styren plastic boxes.

The Elgon bees 2014-2015

The Elgon groups were established with new queens in 2014 and transfered successfully to Mann Lake’s 4.9 and with big difficulties to Anels 5.5.

The queens in the LC colonies were very hesitant to lay in their large cells. One queen totally refused.The broodnest of that queen consisted of only two shallow SC-frames. The resulting colony was of course small going into winter in 2014, but it wintered together with the other two LC colonies in their test apiary.

Most of the colonies, SC and LC, were treated in 2014 with thymol but mostly only in May. So this Elgon test groups of 3+3 were not managed in regard to the Varroa mites, similar to the Carnica groups. In the Carnica colonies the varroa populations were evened out between them, by treating them with home made thymol pads in September 2014.

The Elgon test colonies were taken from different apiaries and the varroa level in the colonies were not known when they were brought to the test site in late August. Earlier in 2014 the colonies who had wingless bees were treated with thymol, in May that was.

The LC part of the Elgon bees 2014-2015

In spring 2015 the Elgon LC group continued to create problems as the bees protested against using LC combs for brood by supersedure their queens, probably in an adaption process.

In April before grafting time and any drones were flying one LC-colony was queenless. The new virgin queen had of course failed to mate and was gone. I combined the queenless colony with the mini colony (the one with the queen that had refused to lay but in the two shallows). This queen still refused to lay in any other comb than the two shallows, so I tried to fool them by giving them a couple of 5.3 mm cell sized plastic frames on each side of the SC combs. That worked. When the 5.3 were filled on each side of the 4.9 they started on the 5.5 next to the 5.3.

It seems it is the workers that prepare the cells for laying, not the queens that are deciding in which cells to lay. (This experience is also in line with what is written in old books from beginning of 1900, that when broodnest have 5.1 you could use 5.6 in honey supers without excluder as the queen didn’t lay in the 5.6.)

In late April 2015 the third (now the second as the other two were combined) LC-colony had a virgin. They were also trying to supersedure their queen. No drones available yet. So she failed. The colony got a queen cell in second half of May. That queen got laying. This colony had 5% varroa level in August and got thymol.

The first colony (former first and second combined) got a small piece of thymol (actually both parts that were combined got half a piece each) early in spring to help against eventual patoghen problems as they had different kind of problems (weak but queenright and queenless). This colony showed only 0.3% Varroa level in August and got no treatment.

The SC part of the Elgon bees 2014-2015

In 2015 the three Elgon SC colonies developed well. Splits were made from two of them. One failed, but finally got a laying queen very late in season. It ended up weak. It was lost during coming winter, the only loss of the Elgons. The smallest of the overwintered colonies had a queen that was laying badly. It was killed and replaced by a ripe queencell.

Four of the now five colonies showed crippled winged bees in July and had Varroa levels between 2-7%. Even the 2% colony showed a few DWV-bees telling me the virus levels in the colonies were quite high. One 3% had no DWV, the weak one mentioned above and it was the only one that didn’t get treatment.

Because the varroa populations in the colonies weren’t allowed to grow strongly (still there were enough viruses in 2015 after years of somewhat higher varroa and virus pressure in the Elgon apiaries of Erik Österlund), the virus amounts in the colonies decreased and also there was no silent robbery. And the varroa populations were evened out at a low level. Thus the situation now was much more comparable with the varroalevels in the Carnica colonies in autumn 2014

The Elgon bees had better nectar flows than the Carnica in 2015 and the Elgon colonies gave a good crop from the Heather in 2015. The average crop was about the same for both SC and LC colonies. In August none of the SC Elgons had above 3% varroa level. They had 0%-3%, and got no more thymol. No colony swarmed in any of the test apiaries.

The Elgon bees 2016

In spring 2016 one of the Elgons, the very weak one in the SC-group died (as mentioned above). Both LC colonies survived.

The LC part of the Elgon bees 2016

In the LC-group splits were made from both colonies. Weather was bad and one failed to produce a laying queen. It got a new ripe queen cell. The parts with the ”old” queens (from the year before) both superseded their queens, in line with experiences in 2015. This year they waited until beginning of summer when there were drones around. Maybe the bees had adapted somewhat to LC now.

The season of 2016 was very bad so no crop was secured from the LC-group. In spring the varroa levels were 0.3% in all four colonies (they became four after splitting in late May). In early September it was 0% – 8.6% – 0.9% – 4%. The two with highest levels were treated with thymol. The other two not. We can see that two colonies had very low levels of Varroa mites. This indicates a good genetic set up for Varroa resistance, also to be able to work with large cells apparently. The queens in the colonies with low Varroa level are sisters, mated in the test apiary. They are daughters to one of the colonies in the apiary, one in a split. The other as a result of supersedure in the mother colony producing this split.

The SC part of the Elgon bees 2016

The four remaining colonies in the SC-group gave a split each. Season was bad and two of the splits failed. A small crop was secured from the strongest of the colonies.

The two colonies with two year old queens supersedured these later in season. The 6 colonies all had 0.3% varroa levels in spring. In August the varroa levels were between 0-1.7%. As we had decided not to keep more than five colonies in each of the four parts of the test, colony no 6 of the SC-ones (the one with 1.7%) was removed from the test area. It wastreated with a small amount of formic acid to get an idea of the mite load and also test the shaker method. It fell 10 mites in a couple of days. The other 5 colonies remaining at the test site didn’t get any treatment.

The Elgon bees in the beginning of 2017

All four colonies in the LC group wintered well, in spite of that two of them were almost too weak, those that had had the highest Varroa levels and been treated.

One of the five SC colonies defecated a lot on the outside of the hive, though not much inside. They did not have a large amount of honey left for winter the previous autumn. And it was of good wintering quality. The winter before all colonies had had a large amount of difficult winter honey, from heather. The colony that died was the strongest and smallest Varroa level. It measured 0% on 400 bees. The was a good amount of food left in the hive after it had died. The colony had an old queen, and just a few meters there had been quite some traffic during late winter from a tree harvester. The other colonies looked fine, with almost no defecation.

Harvest and Varroa level 2015 and 2016 in SC and LC parts of the Carnica bees. The sites for Carnica and Elgon bees are not comparable as the Carnica site was didn’t have the same amount of food sources. Click on the picture to get it bigger and of better quality.

 

Harvest and Varroa level 2015 and 2016 in the SC and LC parts of the Elgon bees.

RESULTS

Losses

The losses in the Elgon groups have been quite normal, on the lower side. It has in percentage been higher in the Carnica groups, especially among the LC bees. The higher amount of losses can be explained by the low availability of pollen and nectar, especially during 2016. That’s why the test site for the Carnica bees has been moved. One conclusion is that during times with small amounts of available pollen and nectar a solution could be to feed the colonies fondant/honey and pollen to develop healthier and stronger colonies better adapted to survive winter.

The strategy of 3 %

The strategy to measure the Varroa level a couple of times during the season and use Varroa treatment (dish cloth pads, about 50 x 58 x 1.5 mm [2”x2”x1/16”], drenched in thymol) when/if the Varroa level is higher than 3 % (only treatmnent in these colonies, not in those below 3 %) has minimized reinfestation, maybe altogether. You thus get a true picture of the Varroa level in the colonies and thus a better selection of the most resistant colonies and the most susceptible ones. You could for example have expected that the different cell size groups had affected each other so that eventual difference in the varroa levels had evened out, especially among the Carnica bees as the two groups there were only 30 m apart.

Little need for Varroa treatment

Relatively little of Varroa treatment has been used, probably partly explained by the absence of reinfestation, no silent robbing. Most treatment has been used in the LC colonies of both the Elgon (2016 when reinfestation had been removed) and Carnica (2015, in 2016 there was no LC left) colonies.

The strategy of 3 % seems to have eliminated the need of Varroa treatment in the SC part of the Elgon bees due to elimination of reinfestation and enough good development of the varroa resistance with the Elgon bees.

This strategy has also lessened the need for varroa treatment to every second year with the SC part of the Carnica colonies and the need for treatment then has been small. Thymol in this context has been effective.

Cell size and fitness

In the LC part of the Carnica bees the need for treatment has been bigger probably because of a quicker development of the Varroa population. It seems fitness has been lower here probably partly due to the bad pollen and nectar availability. But fitness may also be lower because of other reasons. The Carnica LC colony that died in May did not die due to high varroa level. Lack of protein and/or other pathogens (like nosema) can be the cause. The Carnica test site is moved to a place with better food sources.

One can object to this conclusion of lower fitness for LC bees because the number of colonies are low.

On the other hand were all original queens in the Carnica group sisters and all colonies in SC and LC groups (Elgon and Carnica) are behaving consistent in this respect. And any difference in fitness between the two cell size groups among the Carnica bees should have been to the advantage of the LC colonies because the SC colonies had become inbred. Usually follows a lower immune system with inbreeding. Possible impact of this small distance would have been small(-er) difference in the varroa levels between the two groups due to evening out of the varroa populations. The 3% strategy, measuring varroa levels and treatment when it was above 3%, lowered the varroa populations enough to eliminate (totally or enough) the silent robbery.

In 2016 the only colonies that needed treatment were in the LC colonies of the Elgon bees. It should though be noted that with a stock of bees that have been selected for Varroa resistance it is possible to find colonies that are resistant also on large cells. Two colonies (with sisters queens) had very low levels of Varroa mites.

The honey crops, the bee strength of the colonies indicates, and the resulting number of colonies in the SC and LC parts of the stocks of bees indicates that it is no disadvantage to use small cells in the broodnest, rather the contrary.

 Summary of production of new bee colonies, increase in the number of wintered bee colonies. These figures could be seen as a measure of the vitality of the different cell size groups. There is a difference to the benefit of SC bees both in the E group (Elgon bees) and the C group (Carnica bees). Click on the pictures to get them bigger and of better quality.

 

Suggestion on a breeding program for increasing Varroa resistance in a bee population. The background for these suggestion is the results of this project, so far.

 

Reworked website with new info

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Hello dear beekeepers!

I’ve been reworking my old website. not my blogs. The English part became ready enough to be published and I launched it on http://elgon.es

elgon-website

There are quite some new material there. In the article “Resistance breeding” some of the experiences from 2016, very positive and quite important experiences. On that topic there will be more info later on.

This website is so called responsive, which most are these days. It means that it automatically adapt to different screen sizes, down to that of a cell phone. It’s made with and easy working and free app called Rocket Cake.

Lasting learning?

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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.

Small cell size important in breeding Varroa resistance

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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.

Struggles for the survival of honey bees

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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.