Posted 16 December 2005
Inbreeding in Honeybees - A Possible Solution to the Current Widespread "Disappearing Bees" and Queen Losses Mystery.
By Eric McArthur
Many years ago, in the mid seventies, when I started selling queen bees and nuclei, I was approached by a beekeeper on one of the islands off the West Coast of Scotland. This beekeeper was the only beekeeper on the island and he was having great difficulty making colony increase from his small number of colonies. He had been making up queen less nuclei and allowing then to raise their own queens. However his efforts came to virtually nothing with failure after failure - in his 'best case scenario' he would find eggs and brood in some of the nucs but within a short space of time the bee population dwindled and the nucs failed. Around this time I had just finished reading about German pure breeding techniques (Korung), in isolation mating apiaries on the off shore islands adjacent to Ost Friesland. The limitations of 'line breeding' by these breeders had long been understood and the minimum number of colonies required to minimise inbreeding in their parent stocks had been well established.
The Scottish island beekeeper was in a classic inbreeding situation - small number of colonies in isolation over an extended period of time: Result - a chronic loss of heterosis (hybrid vigour). I stated my opinion on his plight to him and he duly received 4 - 4 frame nucleus stocks. I advised him that no matter how good the 'new blood' might be - not to buy his next batch of bees from me - to save him unnecessary expense I advised him to merely purchase queens and introduce them to queenless nucs. Some three years later a happy beekeeper phone to tell me that he had a thriving operation and the bees were doing just fine "Thank you very much"! Right you may well ask. What has all that to do with the current seemingly world wide phenomenon of queen loss, poor mating results, colony loss and 'Marie Celeste' empty hives - everything I reckon!
I was fortunate to attend one of Hampshire College's Advanced Beekeeping NDB Preparation Courses in the late 70's. The participants were given the opportunity to cover all aspects of beekeeping visiting honey packers, commercial beekeepers and commercial queen breeders. The particular breeder we visited had been a partner in ROB Manley's Honey Farming business - I do not intend to name him! However he was producing thousands of queen bees for the market each year using a single 'high performing' queen mother and selling these bees in large numbers to individual beekeepers and many commercial beekeepers - virtually flooding particular areas with related queen bees. Now many of these queen bees would be used to produce the following generations of queens which in many cases might have exacerbated any potential inbreeding problem, as occurred in the Scottish island example mentioned. However the situation here was different - because instead of an isolated island the surrounding area was probably inhabited by numerous feral colonies and many other beekeepers. In my opinion the presence of these feral colonies not only swelled the numbers of potential 'mates' for the to be mated queen but was also instrumental in inhibiting an inbreeding situation by enlarging the gene pool available to the virgin queens.
So what? Well, it is a well established fact that any bee colony infested with Varroa will meet it's maker within 3 - 4 years if untreated. Feral colonies go of course untreated and many, even most are lost. Not only does this reduce the numbers of potential mating partners for virgin queens but each lost colony represents a loss of a unique gene pool. Notwithstanding the gross anomaly of the thousands of related queens produced by the large queen rearer concerns over time, most beekeepers in Scotland and probably the world have been encouraged to - breed from their best, (very best?) colonies over many years - unwittingly eliminating vast reservoirs of genetic material in the interests of 'maximising' honey returns. As a matter of fact a well respected College adviser of the 70's whose workshop on Queen Rearing I attended advocated that as well as 'breeding from the best' that it was really only necessary to use one drone colony for mating purposes. How many beekeepers had this very well respected and well liked man set down the road to hell ? His teaching was only saved from causing beekeeping despair and despondency by the abundant feral colonies existing at that time, in my opinion.
The feral and many smaller beekeepers and their colonies, thanks to the predations of Varroa, are virtually all gone world wide; beekeepers are still practising 'breeding from the best'. Regional gene pools over time have diminished to the stage where problems are now beginning to be so severe that beekeepers are taking notice - but completely baffled by the situation. Be baffled no more! Start now taking your bee breeding seriously and encouraging your local associations country wide to exchange breeding material and do their homework relative to the minimum number of colonies required as parent stock to maintain a 'sweet gene pool'. Only by doing this will you begin to eliminate some of the important parameters besetting the world's honeybees and Scotland's bees in particular.
I say again the huge agro-chemical multis should be falling over themselves to finance such breeding procedures in an attempt to get themselves 'off the hook' of a seriously bad press about their products.