Europe versus USA: breeding varroa resistence

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

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

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

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

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

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

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

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

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

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

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

VSH is active on drone brood as well

In my former post I wrote: “When I first read that bees don’t uncap and clean out drone pupae, as they do of different reasons with worker pupae, I was a little bit surprised as I saw it ‘all the time’.”

I got this information from a paper by Rémy Vandame, Serge Morand, Marc-E. Colin, Luc P. Belzunces: Parasitism in the social bee Apis mellifera: quantifying costs and benefits of behavioral resistance to Varroa destructor mites, Apidologie 33 (2002) 433–445. In a reference to Rath W., Drescher W. (1990) Response of Apis cerana Fabr. towards brood infested with Varroa jacobsoni Oud. and infestation rate of colonies in Thailand, Apidologie 21, 311–321.

But the findings were made with Apis cerana bees not Apis mellifera. This applied to  removal of pupae from cells artificially infested with mites, so these mites had no offspring. Thus it was not ‘true’ VSH tested.  You find it under the subheader 1.2. Removal behavior:  “When brood is artificially infested, bees remove only infested worker brood but not infested drone brood (Rath and Drescher, 1990).”

It seems this removal of worker brood (and lack of removal of drone brood) in Cerana bees is not applicable to VSH but to hygienic behavior. If it should be applicable also to VSH in Cerana bees, it opens up for a conclusion that Mellifera bees maybe could be bred to be more resistant to Varroa than Cerana…

Oh, I realized now that Cerana can’t ever uncap a drone pupa, hygienic or VSH, it’s capping is too hard. The drone capping even has a breathing hole. So you can’t compare it with Mellifera really when it comes to uncapping drone brood or not.

Jeffrey Harris found (with Mellifera bees) that VSH is active on drone brood as well, but not as much as on worker brood.  For the full text just register here and download:

Dragging out drone pupae


When I first read that bees don’t uncap and clean out drone pupae, as they do of different reasons with worker pupae, I was a little bit surprised as I saw it ‘all the time’. Then I read it another time and I started to realize that maybe my bees were doing something unusual.

When Varroa mites first started to create havoc in my apiaries it was not unusual to see sights like this

DronesDraggedOut2008  I’m glad I never see things like this anymore. This was in 2008.

Now I can see a few on the cardboard below the entrance. I make a note and look closer on that hive every time I visit the apiary. It may turn up with wingless bees. I see fewer and fewer of them, glad for that. When I do I give the colony one or two pieces of dishcloth with 4-5 grams of thymol each, for at least ten days, but not more than three weeks. Anyway after 14 days nothing left almost of the piece. Some need more than once. More and more nothing. In average this year 5 grams/hive. Previous couple of years 10-15 grams per hive. None-selected colonies are recommended to have at least 50 grams per hive and year, for comparison. I tried in 2008-09 to use nothing and almost lost all, in spite of the African genes and small cell size. The mites that came were virusbombs I suspect. And no epigenetic and genetic adaption and selection had taken place. Now the situation looks much better. And still some drone pupae are seen being dragged out. Even a mite on this picture. Do you see it?

DronesCol3 Click on the picture to get it bigger then click on the back arrow up in the left corner of the web-browser to come back to the text.

Epigenetics, genetics and breeding locally adapted bees

Randy Oliver Randy Oliver in Sweden 8 Dec 2013

7-8 December, Randy Oliver California USA, Steve Pernal Canada and Mark Goodwin New Zealand had a workshop on parasites and pathogens, mainly Varroa and American Foulbrood. Mark Goodwin with the help of video Skype. I only could participate on Dec 8. I overheard good teaching, mostly on handling AFB and breeding for Varroa resistance. I want to share somewhat of what Randy Oliver gave us, as I understood his teaching.

Locally adapted bees

Randy stressed the importance of locally adapted bees. Even if you happen to breed resistant bees, the queens people buy from you might not be resistant at their place. They may contribute in developing their bee stock, but probably adaption to the circumstances that form the new situation may take some generations.

Epigenetic finetuning


Epigenetics is the first adaption process that takes place in respons to a changed situation – bees and queens moved to a different location with different nectar flows and climate – newly arrived pathogens and parasites – or new varieties of pests and parasites. The genetics at hand in the bees respond to the differently chemical environment that these changes create and causes their DNA to be read and be used differently by them to express a better use of resources and a better defense against enemies. These changes will be inherited to next generations and may well have to be settled during some generations for best effect. This is an adaption process.

HDRtist Pro Rendering -


During this process selection also is taking place, mainly through culling of the least fit, those that can’t handle the new situation die – or you shift the queens in those colonies. And a changed variety of bees will be created with a different setup of gene varieties, alleles. This changed genepool of the population of colonies at this place will be adapted to the new situation. Another adaption process going on, hand in hand with the first one.

Colony diversity

Genetic diversity in the bee colony

It’s not only one enemy or difficult situation the bees have to handle. And here is the genetically different sistergroups in e bee colony very useful. Not all bees have to be able to detect Varroa mites in broodcells and remove those pupae with fertile mites. It’s enough with maybe a couple sistergroups of workerbees. The other ones maybe needed for taking care of other things in first place.

Genetic diversity between bee colonies in the population

A sudden changes in climate can cause most colonies to die, un unusually hard winter or a long dry season. Those few surviving will be able to rebuild most of the genepool again – if the queens are mated to several drones, from many of the colonies in the locality where a group of colonies are forming a subpopulation of bee colonies. This is one of the reasons why queens rarely should be mated at a mating station where a few closely related colonies produce the drones for the virgin queens. For a sustainable stock of bees.

In a breeding program, to give the bees the best resources for both the immediate and the longterm adaption – genetic variation inside the bee colony is important, but also between the bee colonies. This gives the bee stock ability to keep a high variation in the colonies over the years.


  • Select for the best; but it may be even more important to cull the worst.
  • Be sure to maintain genetic diversity if you are controlling the drone pool – breed from a large number of queens each year.
  • Breeding from only a few queens can rapidly lead to inbreeding. If you only breed from a single queen one season, all the drones the next season would all share the same grandmother.
  • If you only have a few hives, swap queens with other beekeepers in order to maintain genetic diversity.

Breeding varroa resistence: Germany versus USA

The other day I received Imkerfreund 12-2013 in my postbox. In this issue of the German bee magazine I found an interview with the scientist leading a varroa breeding project involving beekeepers. It’s a project that has made some progress.

A German strategy

Germany has had varroa for about 40 years. And they mostly try to breed pure Carniolan bees (carnica) and pure Buckfast with the help of isolated mating stations (and insemination). The main varroa treatment concept is the following in the south of Germany.

  • April-June    Cut dronebrood and make splits
  • July              After harvest in July treatment with Formic acid
  • August          Four weeks later the second treatment with Formic
  • September   The third treatment with Formic if mite downfall after treatment no 2 is too high
  • December    Treatment with Oxalic acid, trickling of sugarsolution with oxalic


Their breeding program has two resistance parameters: pinkilling a square decimeter of brood (similar to freeze killed brood) and measuring the development of the varroa population during the season. Besides traits like low swarming, good temper and a honey crop. Their progress: being able to skip one of the summer treatments with Formic acid (as far as I understood the German article).

An American strategy

USA has had varroa for about 25 years. Few try to breed pure race bees like the Germans. Ineminated and naturally mated queens are used. The main varroa treatment concept for smaller operations are aimed at organic treatment (involving formic acid, thymol, drone cutting, hops) and treatment free (involving small cell size, topbar hives). Bigger operations most often trust different syntetic miticides, formic, thymol and hops.) Americans are more focused on treshold counts of mites for the time to treat.

The Russian bees from the very east of Russia, the Primorski area, is one quite succesful undertaking started and developed by the USDA. A number of beekeepers have formed an association to take care of the 18 lines of these bees. They are treated much less than ordinary bees against varroa. With these bees you have to watch out for swarming.

The VSH-bees are influencing most of the other efforts of breeding resistant bees to varroa mites. These bees are a mixture of all kind of bees. Here you find most of the traditional beekeepers that don’t use any treatment against varroa mites, for example John Harbo, , and Adam Finkelstein,

HarboBeeCo Carol and John Harbo

Beekeepers in different states are forming breeding organisations funded by the governement, like this one:

There are those in Europe forming good projects and those already not treating against varroa either, but with this article I want to get attention to how little progress is made with the strategy mentioned above in Germany and how great achievement is made with the VSH-breeding, focused at the start on one trait: VSH. Then on the other. Something has to be learnt here.

Actually resistant bees were achieved already after very few years, by Harbo and Harris in 1995-98 in USA. They started with survivor colonies of any type of bee they were given. The only one parameter they focused on first was VSH: Varroa Sensitive Hygiene. See other articles here in the VSH category. This development of resistant bees have to be done in all kind of regions differing in climatic and other local characteristics, mites and pathogens for example.

It’s time for Europe to learn the lesson and form breeding projects together with beekeepers where ’central’ areas are formed fairly isolated from other bees. All bee colonies in these ’small starter’ areas are part of the program. An effective way of using funding money from European Union would be to support such projects.

Peter Donovan has moved on


Peter Donovan was the longterm, faithful and skilled coworker with Brother Adam at Buckfast Abbey in southwest of England.


He came to the abbey 1939 at the age of 12 when the war started and helped Brother Adam in his work with the Buckfast bee. Already here he started using his typical tie, always with him during work. Later he added the blue cap.

During his military service he was stationed in the far east. When he came home he returned to the bee departement at the abbey to work for and with Brother Adam.

DDonovanKnoblauchSherberton Carrying mating nuces from the mating station Sherberton on Dartmoor, here together with J. Knoblauch. Brother Adam had other persons working for him during the years as well, both munks and non munks.

When Brother Adam died Peter continued his work developing the Buckfast bee, testing and refining new combinations of subpopulations (races) of bees, until several years after his retirenment age.

DDonovanBesök Inspecting colonies in the home apiary showing visitors from Germany possible breeding candidates.

Peter Donovan was highly appreciated as speaker at conferences. We invited him to Bee-85 in Sweden together with Brother Adam and Steve Taber. He has been to Germany and Canada, not the least to many bee clubs in Great Britain. In his later years he helped the Canadians to build up their Buckfast strain of bees. He also collected material to publish an instructional DVD about beekeeping at Buckfast Abbey. Let’s hope it will be published one day. Today the Bee Departement at the Abbey mainly produces honey for sale at their gift shop.

When John, his son, phoned me I reacted with great sadness. I had learned to know Peter during many years and appreciated his upright and humorous personality. We kept in touch during the years, from my first visit in 1983.

The funeral ws held by the abbott at the monastry December 16 and he is buried at the monastry. Chief mourners, his wife Grace and son John.

HDRtist Pro Rendering - Peter Donovan, born 1927 Aug 27, died 2013 Dec 3.

Efforts for resistant bees give results

VSH breedersOrgDec13

I really work for getting bees that can handel the varroa mite themselves. You get results when you do, but it’s extra work and sometimes it’s difficult to interpret what you see. And you loose some bad bees. And some not so bad bees don’t give any honey – and you shift the queen in those. That’s the two most important results from such a work.

I got a good report in the discussion forum of That’s encouraging.