During the years I have received numerous feedbacks from our customers. Some of them are good some more critical.
This blog update is done solely because of a feedback I specially asked for from Luca Consigli, our partner in queen rearing:
Copy from E-mail 3.10.2018:
”Running probably the biggest company into live bees’ production, my goal is to search always for breeders with best quality, honey production, low swarming tendency and no brood diseases breeders. To reproduce and sell to our customers. I met Juhani reading his varroa resistance story. I was curious to test varroa resistance tendency on big quantities and check also their commercial skills (I had bad experience with other varroa resistance queens in the past. No commercial characteristics so little honey production, aggressive temperament, sensitive to diseases or very little brood all season long).
Lundén’s breeders were left quite 2 years without treatments with other Buckfast breeders. They were the last to show collapsing signs. So, my conclusion was: best varroa tolerance (not varroa resistance in my Italian area just because hives density is very strong, and they suffer continuously varroa re-infestation from other colonies) and average commercial characteristics.
My real surprise was after 1-year test of f1 generation (Lundén daughter crossed with our Buckfast drones):
Best honey production, biggest and compact broods, no foulbroods, chalk, viruses but still low swarming. Good temperament and overwintering.
Yes, for sure they lose some of their varroa tolerance but still able to work from January to July with no varroa warning sign on bees and inside brood.
Probably it’s a very good cross because their isolation in Finland crossed with high standard stabilized European Buckfast score an optimum and positive hybrid vigour.
So, we decide to have an exclusive partnership also with Mr Lundén, to test his material on big numbers and to improve our Buckfast genetic bank with Varroa resistance new stock.
Very lucky decision by the moment.”
LUCA CONSIGLI, APICOLTURA LA FENICE (TRANSLATION FROM A SPEECH IN A MEETING IN BASQUE COUNTRY, SPAIN, FRANCE)
In mid-June 2015 I got a phone call from Kuortane about 80 km north from here. It was Reijo Avara calling and he told that near him is living a beekeeper who has been treatment free since 2001. His name is Heimo Kangasaho. Reijo said that Heimo had been with great enthusiasm reading my writings about treatment free beekeeping in “Mehiläinen” beekeeping magazine. I don´t know was Heimo too shy to make this first call or what but this was the beginning of our friendship.
My first reaction was firm denial. “Cannot be true!” I said to Reijo. But Reijo was persistent. He told me Heimos story, this is how it goes.
Heimo had been a beekeeper long time ago, but life forced him to give up with bees for a while. In 2001 he decided to start again, and he bought one beehive from Alajärvi, about 40 km north from Kuortane. This hive was the last living hive of a 90-year-old man who had to give up with bees. Heimo and I are pretty sure this old man probably did not even know mites existed.
I knew very little about mites 1996 when I suddenly got hit by them. Those late 1990 -years mites were almost everywhere in Finland, and I remember feeling a bit ashamed, almost like a fool, because of my ignorance. After all I have a university degree in beekeeping. It was a shock. By 2001 mites were all over southern Finland. Only Lapland and Åland were places where varroa had not come or spread, mostly by beekeepers themselves.
The more I listened to Reijos` talk the more I realized Heimos` story could be a very interesting one: In 2001 an old beekeeper is selling his last hive form a region which was surely hit by varroa years before, but by that time education and knowledge of treatments had not reached older beekeeper generations.
This last hive could well be a lucky survivor.
Heimo got home with his one hive and years went by, bee yard got bigger. Heimo has never cared about mites. After all he was a beekeeper before mites came. Sometimes Heimo went to beekeepers’ meetings, mites were of course major issue many times. When he told fellow beekeepers that he had not treated against mites they warned him firmly. “You must treat, or you lose them all!” they said. But Heimo is like me: just one hell of a stubborn beekeeper who does not like to be told what to do.
Many, many years Reijo Avara did not treat either. But in the end, he got so many warnings about his hives dying for sure, that he gave up and started to treat, even though he had had hardy any troubles with mites. You might say he was brain washed, but his reaction is very human. We listen advise and try to be wise and learn.
The story goes on
We first met when Reijo and Heimo drove to our home yard in June 27th 2015.
They had one black queen in a mating hive with them. “This is for you” Heimo said “but I don´t know if she has been mated” The weather had been rainy.
We went to see my bees and then looked some queen rearing gear Heimo has designed and build himself. I made my first visit to him couple months later.
In 2016 I went to see Heimo again and gave him one laying queen. Heimo told me later that after she had started to lay eggs in her nuc the bees changed her immediately. This daughter queen´s hive (F1) brought the biggest honey crop in Heimos` yard this year (2018): five Langstroth boxes full of honey, somewhere near 150 kg.
We want to forget about year 2017, it was so rainy that there was hardly any honey crop in this part of Finland.
The queen I got 2015 form Heimo had mated in his yard. So, it was a pure Kangasaho queen. I raised some daughters from her. I have already reported about the results before but put together the results are promising and there surely is varroa resistance in this queen. Variation in her daughters has been great, and it seem Heimos` bees are surviving in somewhat different way that mine. They build larger brood areas, but that is what F1 daughters do, one must consider heterosis which may have an effect too.
Luca Consigli (Puglia, Italia) reports also fantastic results with F1 daughters of our queens.
Pure Lundén Resistant Queens make smaller than average brood area, but of course not treating must have an effect. Mite infestation levels were aroud 2% this summer.
Visit to Heimo Kangasaho 21.9.2018
We neither have issues with angry bees. That is probably why I forgot my bee suit home. Never the less we inspected at least 10 hives and transferred honey combs from hives with more stores to lighter ones. We checked some queens too and saw some beautiful brood areas.
Just in the end of our operations I got one sting near my right eye.
We saw some mites, behind the hive entrance reducers and some even on the bees. Heimo loves gardening and has for instance pear trees.
Heimo is feeding quite late. I have already finished with winter feeding, but he had not even started. Situation was similar in my last visit in September 2017, after the record breaking rainy and cold summer, his hives looked weak and had almost no food at all. But somehow, after Heimo feeded them about 10 litres sugar, they managed to overwinter. No bees left outside died in winter, some died in spring and some small nucs brought in cellar to overwinter, died too.
Bees looked very well. His bees are mixture in colours, although he has been selecting in favour of black colouring. This hive has mostly black bees, can you find the queen?
The autumn has been warm, and his bees have been collecting nectar from clovers nearby. They all had plenty of stores. I was relieved. We put some feeders on, sugar syrup was waiting on his car trailer.
I brought Heimo bear fence gear, had one extra at home. He knows there has been a bear moving nearby, last summer it turned his trash over, made some marks on a tree and this year other villagers have reported seeing bear on the opposite bank of the Kuortane river. This bear in Kuortane has not learned to attack beehives yet, but hopefully he will assemble the gear. His bees are so valuable, that it is better to be safe than sorry.
Beekeepers in Kuortane and in many other similar places in Ostro Bothnia sort of live on islands: fruitful river bank fields where bees find plenty of honey and pollen surrounded by large meagre forests and swamps.
Beautiful red clover field in full bloom in Kuortane that day.
The surrounding areas are very often so rugged that bees cannot produce big enough honey crop for any beekeeper to be interested. There are no wild bees this north in Finland, swarms usually die in their first winter.
Heimo has many types of boxes: insulated wooden boxes and Styrofoam boxes from various manufactures. Most of his boxes are uninsulated and wooden, just like mine, mostly Langstroth frames but also shallower equipment.
So far Heimo and his bees have been living happily together with mites. Hopefully his beekeeping neighbors realize the importance of his work too.
There has been breeding and research to develop varroa resistant bees for a long time, over 30 years now. That is good, although nobody has come up with perfect varroa resistance.
Since now there has been very little talk about the transition period after varroa resistant bees have been developed. Only few people have openly come up with ideas how are we, TF beekeepers, going to be the majority. No matter however long that might take.
One of the first ones was Josef Koller. He developed the idea of ROOTs breeding -system. I wrote about it in one of my very first writings in this blog.
In ROOTs breeding system the basic idea is to start with one bee yard and keep it TF whatever comes. The place of the first bee yard should be as remote from other beekeepers as possible. Josef realized that it will be struggling but he reasoned that in the end the bee yard need to be expanded. New TF bee yard should be placed in the flying range of drones. To maintain versatility and avoid inbreeding nucs are made of all, strong enough hives. Hives, which have given their queen to a nuc, are allowed to raise a new queen for themselves. New queens mate freely in Josef’s plans.
Little by little the modest start will grow into ever largening circle.
Or will it?
In July 2014 bear destroyed my mating nucs in Haukkamaa mating station, which had been in use for 20 years. To be honest the fight with varroa had drained all my strength, bears were just too much. I gave up. I had to think something new, I did not want to take my bees 30 km into the darkest forest and let the bear jeopardise my breeding work. Josef’s idea came to my mind, I decided to give it a go. I thought circumstances in Central Finland would be ideal, few other beekeepers around. I realized we have at least one down side: there are no wild bees in Finland.
Now after 4 years I am ready to share something of what are my ideas of ROOTs breeding system.
These 4 years nearly destroyed my beekeeping. But was the reason ROOTs breeding or 3 rainy and cold summers in a row, that is hard to say.
The main problem is that in the beginning of TF breeding free mating is not working to the advance of TF breeding. The TF hives will raise less, and lower quality drones compared to other hives nearby. Free mating may be good to keep up versatility, but there is no breeding advance. In the contrary: varroa resistance will retard and hives become more mite infested. The bad circle is hard to stop once it has begun.
In the beginning of TF breeding it is essential to mate the best with the best. This can only be done with reliable mating stations or insemination.
FORT KNOX beekeeping, the new initiative from Poland
In April 2018 there was the first European Treatment Free beekeeping conference in Austria. The main interest was captured by the Polish group “Wolne Pszczoly”. A quote from their web site, http://wolnepszczoly.org/about-us/ :
“Fort Knox” is a gold reserve in the USA. That is why we used that name for the reserve of our “gold” – treatment free bees. The initiative is about giving “insurance” for all beekeepers that want to be treatment free, but are afraid of losing hives and start over again. Each beekeeper can declare some of his hives to “joint venture” – whatever number he or she wants, but no more than the number of project members (because we could have some problems of meeting the need in a bad year). We still have these hives in our yards – but they have to be treatment free, “promising” genetics, harvested only from surplus (only from what the bees don’t need for successful wintering – so with no, or only minimum feeding sugar). If a colony dies, beekeeper who is in the common project is given a new colony for free from other beekeeper, who had the luck of surviving bees. We started the initiative a year ago, but this year two of us have already been given colonies from others. We think the initiative in time has the potential to gather more and more beekeepers who would be less frightened by the vision of losing all hives and starting over again. We hope that treatment free, productive bees in time will no longer be the impossible dream in Poland.”
They have a lot in common with Josef Kollers ROOTs breeding: free mating of queens, making nucs of the survivors. But in addition, they prefer 4,9 mm wax or foundations less beehives and minimum sugar feeding and beekeeper intervention.
However, the revolutionary part is the mutual responsibility of other members in the group. Nobody is left alone with no bees in case of losses. The group members live quite far from each other and meet at least once or twice a year to share experiences. In these meetings a member who have lost bees is given new hives (only capped brood frames with bees) from survivor stock of other members.
If beekeepers forming such a group would be living closer to each other, I think the odds were more on favour. After discussing with the project members, it seems to me that they have quite a lot against controlled matings. Their basic main idea is that the natural forces of nature will eventually win, and bees will naturally become varroa resistant when let alone. Their belief is that the impact of treated drones will eventually fade away.
Wild bees of Poland may have positive impact, but on the other hand the enormous density of treated beehives in Poland is serious down side. It remains to be seen what their success will be.
If you know some other initiatives in this matter, or have corrections or comments, please write.
The weather has been hot, maybe a bit too hot…
Kysymykseen on vaikea vastata, koska tällaisia mehiläisiä on olemassa vielä niin kovin vähän, eikä täydellistä liene kehittänyt vielä kukaan. Lisäksi on tiedettävä tarkkaan, puhutaanko puhtaista jalostusyksilöistä vai niiden risteytyksistä. Varroasaastunnan määrä vaikuttaa myös mehiläisten käytökseen. Varmaa lienee vain se, että kun jalostuksella jyrkän valinnan avulla pyritään voimakkaasti edistämään varroankestoa, niin se väistämättä vaikuttaa mehiläisten muihin ominaisuuksiin ainakin lyhyellä tähtäimellä.
Varroankesto perustuu moniin eri tekijöihin, joista tärkeimmät lienevät:
– kuolevien tai kärsivien sikiöiden tunnistaminen kennossa ja niiden poistaminen
– joku muu punkin lisääntymistä hidastava vaikutus (kennojen aukominen, kemiallinen harhautus, punkkien vahingoittaminen)
– mehiläisten kestävyys viruksia vastaan
– joidenkin lähistöllä olevien pesien parempi tai heikompi kestävyys (Kefuss: varroa black holes, Lundén: punkkimagnetismi)
Tähänastisissa tieteellisissä tutkimuksissa on pystytty hyvin yhtenevästi todistamaan, että kaikille punkkia kestäville kannoille on ominaista punkin lisääntymiskyvyn huomattava heikkeneminen. Syitä lisääntymiskyvyn heikkenemiseen on tutkimuksissa pystytty toistaiseksi vain arvailemaan.
Kuolevien tai kärsivien sikiöiden tunnistaminen kennokannen alta ja niiden poistaminen vaikuttaa voimakkaasti pesän maksimikokoon ja kehittymisnopeuteen, jos varroasaastunta on suuri. Mutta entä tulevaisuudessa, voisiko olla, että tarkka ja nopea punkkien tunnistaminen ja välitön poistaminen pitäisivät punkkikannan niin pienenä, että puhdistustyö vaikuttaisi vain vähän yhteiskunnan kokoa pienentävästi? Evoluutiobiologi kysyisi, voisiko varroankeston kustannus mehiläispesälle pienentyä merkityksettömän pieneksi? Muutamat hassut punkit putsattaisiin pois ja kaikki muu pesän toiminta jatkuisi normaalina. Mehiläisten koko genomin selvityksessä havaittiin hajuaistiin liittyvien geenien suuri määrä. Tarkan hajuaistin kääntöpuoli voi olla ympäristön ärsykkeistä hermostuminen, jonka hoitaja voi havaita lievänä vihaisuutena, tai ainakin uteliaana pörräämisenä.
Punkki on sokea ja pesä sisältä melkoisen pimeä paikka. Punkki löytää sopivanikäiset sikiöt hajuaistinsa avulla. Voisiko ajatella, että mehiläiset oppivat harhauttamaan punkkia? Jos sikiöiden erittämä ”kemikaalikoktaili” muuttuisi hieman toisenlaiseksi, se voisi olla tarpeeksi, jotta sokeat punkit eivät löytäisi niitä. Kennojen aukominen ja sulkeminen toiminee sekin eräänlaisena harhautuksena, mutta tiedossani ei ole tämän toimenpiteen tehokkuus. Maalaisjärjellä ajatellen voiko punkki olla niin tyhmä, että pelkkä kennon kannen avaaminen saisi sen nousemaan ylös kennon pohjalta sikiön alta kesken lisääntymisprosessin? En usko, mutta tämäkin vaikutus voi perustua kemiaan: kennon sisäisten kaasujen koostumus muuttuu ja punkin lisääntymisen pasmat menevät sekaisin. Viimeaikaiset tutkimukset Apis ceranalla osoittavat että punkit vastoin aiempaa luuloa pystyvät lisääntymään työläiskennoissa, mutta putsaaminen on niin tehokasta, että niitä ei ole aiemmin löydetty. Tämä on mielenkiintoinen tulos, joka antaa uskoa siihen, että myös melliferalla tämä voisi toimia päämekanismina punkkia vastaan.
Punkin fyysinen vahingoittaminen on aivan oma juttunsa, johon ainakin Alois Wallner on tutkimuksissaan ja jalostustyössään keskittynyt. Wallner pystyy tällä hetkellä tulemaan toimeen yhdellä muurahaishappo torjunnalla, mikä on Keski-Euroopan oloissa huomattava saavutus. Myös USA:ssa on ajoittain kohistu ns. Anckle Biter eli nilkanpurija mehiläisistä. Näitä on jalostanut Purduen Yliopisto.
Mehiläisten viruskesto on tavallaan vakuutus, joka varmistaa, että jos punkin torjunta on syystä tai toisesta jäänyt huonoksi, niin pesä ei silti tuhoudu, koska mehiläiset kestävät punkin tuomien ja levittämien virusten vaikutuksia. Mehiläisethän eivät kuole punkkiin vaan punkin levittämiin viruksiin. Tämä on paradoksi, jota pitää hetki miettiä. Jos mehiläiset eivät kuole punkkiin vaan viruksiin niin voisiko olla niin, että virukset muuttuvat heikommiksi? Näin eräs tiedemiesryhmä uskoi englantilaiset Ron Hoskinssin tapauksessa. Hänen pesistään löydettiin DWV eli siivenkutistajaviruksen B kantaa, jonka uskottiin olevan pesien selviämisen salaisuus, vaikka Ron Hoskins oli kahdenkymmenen vuoden ajan jalostanut punkkia kestävää mehiläistä. Puhuttiin ns. super-infection exclusionista, eli kun pesille vähemmän vaarallinen virus pääsee syystä tai toisesta lisääntymään pesässä, se ikään kuin sulkee vahingolliset virukset pesän ulkopuolelle. No, kuten tieteessä usein tapahtuu, toinen tutkimus kumosi tämän teorian. Kun tutkittiin koko Englannin viruskantoja, huomattiin, että B kanta oli hallitsevana valtaosassa tutkituista kohteista. Osa tiedeyhteisöstä on lisäksi sitä mieltä, että B kanta on nimenomaan se vaarallisempi versio.
Itävallassa huhtikuun alussa pidetyssä ensimmäisessä eurooppalaisessa kansainvälisessä konferenssissa, jonka aiheena oli mehiläishoito ilman varroan torjuntaa, esitti John Kefuss käsitteen ”varroa black hole”. Johnin englannin kieli on melkoisen haastavaa seurattavaa, saksan ja ranskan kielen sanat sekoittuvat mukaan, mutta sikäli kun ymmärsin oikein, niin hänen sanomansa oli, että punkkia kestävä pesä toimii kuin musta aukko, josta punkki ei elävänä palaa. Kestävä pesä siis auttaa ympäristöään pysymään hengissä. Raportoin samasta asiasta toisinpäin vuonna 2003: Jotkut pesät tuntuvat imevän punkkeja itseensä kuin magneetti. Tästä on seurauksena, että ne kuolevat, mutta se helpottaa muiden pesien tilannetta. Tämä on luonnon monimuotoisuutta ja normaalia luonnonvalintaa. Luonnonvoimen avulla syntyvä tasapaino voi olla jotain täysin muuta kuin se, mihin jalostuksella pyritään. Luonnon tasapainotilanteessa lajille riittää hengissä pysyminen, populaation koon jatkuva kasvu ei ole mahdollista (vrt. ihmiskunta!). Luonnonvalinnalle riittää, että jos joka pesä parveilee joka vuosi, niin kuolleisuus voi olla 50%. Jalostaja taas haluaa, että kaikki pesät pysyvät hengissä.
Haastetta riittää. Suurimman ahaaelämyksen varroan keston jalostaja saa sinä hetkenä, kun hän lopullisesti uskoo ja ymmärtää, että mehiläiset eivät kuole punkkiin. Voin kertoa, että se on mahtava hetki. Ja samalla saa uuden ystävän, tai oikeastaan tuhansia, punkin, jota tarvitaan jalostustyössä.
Insemination of queen bees is often seen as something very difficult, strange and high tech. It is seen something for the professionals only. It is not. Insemination is very often more needful for a hobby beekeeper than for a commercial beekeeper.
Many beekeepers have bees which are too prone to swarm or sting. Free mating of queens makes these problems continue for ages. What would be a good standard? I would say if a beekeeper must use gloves when working with bees, they are too aggressive. If a beekeeper loses swarms despite of using swarm prevention methods, the bees are too swarmy. Swarming is often seen something evitable. Beekeepers do not believe better bees exist.
In Central Europe there are wide range of isolated mating stations for all beekeepers to use. These are run by beekeeping groups and associations. The idea is that every beekeeper belonging to that group can send or deliver queens, in a mating hive without any drones, to the mating station where they are taken care of by personnel in charge. After mating the queens are sent back to owner and small fee is charged for the expenses. This kind of cooperation is very useful and has been proved to be a powerful tool in bee breeding. All races have their own mating stations, which are for the most part located in either remote forest areas, mountain valleys or islands.
Queen rearing skills are needed if this kind of mating system is used. Many beekeepers know how to raise cells but the use of mating nucs is not familiar. As far as I know most mating stations require the use of standard mating hives, such as Apidea, Mini-Plus or Kirchain. Larger mating hives, such as 5 frame nucs or other structures made by the beekeeper are not accepted. This rule is to make the whole operation run smoothly, and to secure mating purity.
Which drone lines are used in these mating stations? In winter time the results, hive evaluations of the previous years are calculated. Sometimes there are several drone lines to choose from. It is a group decision but the procedure behind these decisions is unknown to me. Something must be agreed of, I believe that the breeding material of “the most famous” breeders is often accepted, and therefore the risk for increasing inbreeding is evident in the long term. A beekeeper with personal view or personal breeding goals may find oneself in opposition. Another, although small, inconvenience is, that timetables must be set up according to each mating stations mating ”rounds”.
Here comes insemination to rescue. Beekeeper can plan all breeding work and time tables freely, choose drones for each queen individually.
If learning new skills is not tempting or too time consuming now, there is always the possibility to use insemination services. There are hundreds of professionals capable of doing insemination work for a moderate fee as a service. I don´t know how many of them are willing to travel across Europe, but here is something to think about: We should have a working system where a beekeeper can just pick a name from a list and order an expert to inseminate new queen bees. This kind of system would require education to all parties. The hobby beekeeper should be able to raise drones and queens in the right time and have facilities ready and all set up when the time comes. It is essential that there are lots of mature drones available and that the queens are minimum 7 days old, preferably 10 days, when the insemination is planned to happen. The queens must have been confined to mating nucs with queen excluder. There must be a place to work indoors: well illuminated, not too hot or cold, electricity and a place to wash hands is needed, too. Poorly performing drones have usually been the biggest problem. If weather is poor, drones collecting should be rethought. Drones and nursing bees can be collected beforehand to smaller nucs and placed in garages etc.
Queens waiting for insemination can be confined to bigger mating nucs, too. Nucs with 4-6 normal size frames work fine. There is no limit to their size, but if very large nucs are used it is a good practice to catch the virgins one day before and place them in a small cage with some nursing bees and candy. It is handy to give 1-2 minute CO2 treatment in the same time.
In this kind of insemination services there could be standard table for charges: fee for a queen, or for time used if the smooth insemination work is not possible and it is due to something wrong with queens, drones or facilities. Fee for travelling costs could be fixed by distance.
If learning new skills sounds tempting, then I advise to buy insemination devices and education from the same resource. This is because all different insemination equipments have their specialties. If you take a course in insemination but the machine you buy is not the same used in that course, there might be some problems.
Kari Pirhonen and I can offer “STARTER packages for HONEY BEE INSEMINATION”: All including set up (devise, microscope, lightning, CO2 gear), everything needed for insemination work plus education in buyer’s location in Europe. Price of this kind of package is depending on many things. If accommodation and food is from “the house” and pickup from and to the airport is no problem, it is of course cheaper than staying in hotel and renting a car.
If you got interested, I would be very happy if you comment this blog writing or you can of course write me e-mail: firstname.lastname@example.org
Selecting for varroa resistance
Is IMP a possibility?
In breeding for varroa resistance in bees, or in any other breeding as well, it is crucial to be able to identify the individuals which are genetically better. To be able to do this all hives must be handled the same way.
In practical beekeeping efforts IPM has often been seen as a possibility to breed varroa resistant bees. This kind of selection is often based on measuring infestations with alcohol wash or sugar dusting methods. The hives with lowest mite infestations are used in breeding.
In these IPM breeding programs infestation threshold is usually set to a certain level. The levels vary a lot, and to my knowledge, they are not based to any scientific information. I have seen figures from 2,5% to 10% mentioned. In fact, any set infestation level has nothing to do with varroa resistance, only the increase in mite population in a time interval is meaningful in deciding breeder queen quality. This fact is hardly ever mentioned in discussions. Starting point infestations are usually not mentioned/measured at all! This is very surprising.
Varroa papulation can develop very fast. Varroa population is doubling every 3 weeks and the number of mites in a hive can raise 20 to 100-fold in one summer. In autumn when bee population is getting smaller, infestation levels raise sharply. This is the main reason why relatively moderate infestation levels are usually used in IPM breeding selection. When using higher infestation level as treatment threshold there is a greater risk of mite numbers getting dangerously high and thus making too much damage to hives before winter. This is one of the most severe weak points of IPM management when choosing breeder hives. If we accept for instance 3% infestation level as treatment threshold, there is much bigger risk of choosing wrong breeders when compared to for instance 5- 10% levels. This is due error in measured data.
Error in data is getting bigger in two ways. Firstly, the low levels of mites make is tricky to measure the number of mites exactly, when using the standard method of 300 bees. Measuring error is easily +-50%.
Hive number Measured in reality between status
1 6 mites 3-9 approved, not treated
2 8 mites 4-12 approved, not treated
3 10 mites 5-15 discarded, treated
From these examples hive number 1 and 3 “passes the test” and hive number 1 is to be a breeder even though hives 2 or 3 may have been better choices. Hive number 3 might actually have been the best choice. Only with some luck the best breeder is chosen.
The other factor causing more error is the short time interval.
Example, two hives: Hive 1, infestation in the starting point is 0,4 %. It may take only 2-3 months and the hive is in the treating threshold. Is such a short interval really enough to evaluate, approve or discard?
Hive 2, infestation in the starting point 0,2%. This hive may just make it through winter without treatments and may well become a breeder next year.
The only difference between these two hypothetical queens could have been efficiency of treatment given to the previous queens and her bees. The previous queens had infestations of 6% (Hive 1) and 4 %(Hive 2) and were therefore discarded. Treatment was given, and the efficiency was 93,3% (Hive 1) and 95% (Hive 2).
99,3% efficiency drops the 6 % infestation to 0,4%
95% efficiency drops the 4% infestation to 0,2%
The marginal difference in treatment efficiency (killing mites of the previous queen) made the beekeeper to choose one hive over other. The treatment efficiencies may vary a lot more and cause wrong decisions.
My observation has been that there is an individual level in which bees start to react to mites. This level may well be over 5%.
If we have threshold of 10%, then 2 % infestation is much more certain proof of breeder quality than in a situation when the threshold is 3 %.
In breeding all hives must be managed the same way. In bee breeding there are many factors causing error in breeder selection, yard, honey crop and management some of the biggest. Therefore, heritable differences are so hard to detect. Low heritability makes decision making even harder and possibilities for error even bigger. But to make the right decisions we need to know: Are the differences heritable or not? This is often done by comparing one sister group of queens to another sister group. In one sister group all queens have the same (possible breeder) mother.
Integrated Pest Management, IPM, in varroa mite control is fighting against this basic rule of equal management.
Breeding is a numbers game, and every time we treat some part of our hives, we get smaller groups of hives which can be compared with each other. Example: Beekeeper has 200 hives to compare in the beginning of his breeding efforts. That is a pretty good number to make comparisons. He treats 50% of his hives annually. After three years he has 8 groups, 25 hives each. After 4 years he has 16 groups 12,5 hives each etc. Hives must be compared and selected within these groups. When making breeder queen selection, sister groups must be compared to other sister groups. This is the only way to ensure the differences are inheritable. In such a small group it is very hard to make any right decisions, because sister groups are not big enough or they are non-existent.
Huhtikuun 7. ja 8. päivänä pidetään Itävallassa Euroopan ensimmäinen kansainvälinen konferenssi, jonka aiheena on mehiläishoito ilman varroan torjuntaa.
Minulla on kunnia olla yksi puhujista.
Osa esitelmistä on englannin kielellä. Saksan kielellä pidettäviä luentoja ei todennäköisesti käännetä englanniksi.