Category Archives: Science

The day job

It’s no secret that I have both amateur and professional interests in bees, bee health and beekeeping.

During the weekend I sweat profusely in my beesuit, rushing between my apiaries in Central and Eastern Fife, checking my colonies – about 15 at the autumn census this year – averting swarms, setting up bait hives, queen rearing and carrying bulging supers back for extraction.

Actually, not so much of the latter in 2017¬† ūüôĀ ¬†I did get very wet though, much like all the other beekeepers in Fife.

The BSRC labs

The BSRC labs …

During the week I sit in front of a large computer screen running (or sometimes running to keep up with) a team of researchers studying the biology of viruses in the Biomedical Sciences Research Complex (BSRC) at the University of St. Andrews. Some of these researchers work on the biology and control of honey bee viruses.

During the winter the beekeeping stops, but the research continues unabated. The apiary visits are replaced with trips in the evenings and weekends to beekeeping associations and conventions to talk about our research … or sometimes to talk about beekeeping.

Or both.

This weekend I’m delighted to be speaking at the South Devon Beekeepers Convention in Totnes on the science that underpins rational and practical¬†Varroa¬†control.

Which came first?

I’ve been a virologist my entire academic career, but I’ve only worked on honey bee viruses for about 6 years. I’ve been a beekeeper for about a decade, so the beekeeping preceded working on the viruses of bees.

However, the two are inextricably entwined. Having a reasonable amount of beekeeping experience provides a unique insight into the problems and practicalities of controlling the virus diseases that bees get.

Being able to “talk beekeeping” with beekeepers has been very useful – both for the communication of our results to a wider audience and in influencing the way we approach our research.

Increasingly, the latter is important. Researchers need to address relevant questions, using their detailed understanding of the science to deliver practical solutions to problems1. There’s no point in coming up with a solution if there’s no way it’s implementation is compatible with beekeeping.

Deformed wing virus

DWV symptoms

DWV symptoms

The most important virus for most beekeepers in most years is deformed wing virus (DWV). This virus¬†“does what it says on the tin”¬†because, at high levels, it causes developmental defects in pupae that emerge with shrivelled, stunted wings. There are additional developmental defects which are slightly less obvious, but there are additional (largely invisible) changes which are of greater importance.

DWV reduces the lifespan of worker bees. This is probably not hugely significant in workers destined to live only a few weeks in midsummer. However, the winter bees that get the colony through from September through to March must live for months, not weeks. If these bees are heavily infected with DWV they die at a faster rate. Consequently, the colony dwindles and dies out in midwinter or early Spring. At best, it staggers through to March and then never builds up properly. It’s still effectively a winter loss.

Our research focuses on how¬†Varroa influences the virus population. There’s very good evidence now that DWV transmission by¬†Varroa leads to a significant increase in the¬†amount of virus, and a considerable¬†decrease in the diversity of the virus population.

So what?

Well, this is important because if we want to control the virus (i.e. to¬†reduce DWV-associated disease and colony losses)¬†it must help to know the proper identity of the virus we are trying to control. It will also help us¬†measure how well our control works. We know we’re measuring the right thing.

We’re working with researchers around the world to define the important characteristics of DWV strains that cause disease and, closer to home, with entire beekeeping associations to investigate practical strategies to improve colony health.

Chronic bee paralysis virus

CBPV symptoms

CBPV symptoms

We’re about to start a large collaborative project on the biology and control of chronic bee paralysis virus (CBPV). This virus is becoming a significant problem for many beekeepers and is increasing globally. It’s a particular problem for some bee farmers.

CBPV causes characteristic symptoms of dark, hairless, oily-looking bees that sometimes shiver, dying in large smelly piles at the hive entrance. It typically affects very strong colonies in the middle of the season. It can be devastating. Hives that should be the most productive ones in the apiary fail catastrophically.

Why is a virus we’ve known about for decades apparently increasing in the amount of disease it causes? Are there new virulent strains of the virus circulating? Are there particular beekeeping practices that facilitate it’s spread? We’re working with collaborators in the University of Newcastle to try and address these and related questions.

I’ll write more about CBPV over the next year or so. It won’t be a running dialogue on the research (which would be crushingly dull for most readers), but will provide some background information on what is a really fascinating virus.

At least to a virologist ūüėČ

And perhaps to beekeepers.

Grow your own

As virologists, we approach the disease by studying the virus. Although we maintain an excellent research apiary, we don’t do many experiments in ‘the field’. Almost all the work is done in test tubes in incubators in the laboratory … or in bees we rear in those incubators.

Grow your own

Grow your own …

We can harvest day-old larvae (or even eggs) from a colony and rear them to emergence as adult bees in small plastic dishes in the laboratory. We use an artificial diet of sugar and pollen to do this. It’s time consuming – they need very regular feeding – but it provides a tightly controllable environment in which to do experiments.

Since we can rear the bees, we can therefore easily test the ability of viruses to replicate in the bees. Do all strains of the virus replicate equally well? Do some strains outcompete others? Does the route by which the virus is acquired influence the location(s) in the bee in which the virus replicates? Or the strains it is susceptible to? Or the level of virus that accumulates?

And if our competitors are reading this, the answer to most of those questions is ‘yes’ ūüėČ

We can even ask questions about why and how DWV causes deformed wings.

Again, so what? We suspect that DWV causes deformed wings because it stops the expression of a gene in the bee that’s needed to make ‘good’ wings. If we can identify that gene we might be able to investigate different strains of honey bee for variation in the gene that would render them less susceptible to being ‘turned off’ by DWV. That might be the basis for a selective breeding project.

It’s a simplistic explanation, but it’s this type of molecular interaction that explains susceptibility to a wide range of human, animal and plant diseases.

Bee observant

Bee health is important, and not fundamentally difficult to achieve. There are some basics to attend to … strong hives, good forage, good apiary hygiene etc. However, it primarily requires good powers of observation – does something look odd? Are there lots of mites present? How does the brood look?

If things aren’t right – and often deducing this means comparisons must be made between hives – then many interventions are relatively straightforward.

Not long for this world ...

Not long for this world …

The most widespread problems (though, interestingly, this doesn’t apply to CBPV) are due to high levels of¬†Varroa infestation. There are effective and relatively inexpensive ways to treat these … if they’re used properly.

More correctly, they’re relatively inexpensive whether they’re used properly or not. However, they’re pretty ineffective if not used properly ūüėČ

Regular checks, good record keeping, comparisons between hives and informed observation are what is needed. Don’t just look, instead look for specific things. Can you see bees with overt symptoms of DWV? Are there bees with¬†Varroa riding around on their backs? The photo above has both of these in plain view. Are some hairless bees staggering around the top bars with glossy abdomens, or clinging to the side bars shaking and twitching?

Don’t wait, act

I’ve no doubt that scientists will be able to develop novel treatments to control or prevent virus infections of bees. I would say that … I’m a scientist ūüėČ ¬†However, I’m not sure beekeepers will be able to afford them, or perhaps even want to use them, or that they’d be compatible with honey production or of any use in Warr√© hives¬†etc.

I’m also not sure how soon these sorts of treatments might become available … so don’t wait.

If there are signs of obvious DWV infection you need to do something. ‘Obvious’ because DWV is always present, but it’s usually harmless or at least tolerated by the bees. My lab have looked at thousands of bees and have yet to find one without detectable levels of DWV. However, healthy bees have only about 1/10,000 the level of DWV present in sick bees … and these are the ones that have obvious symptoms.

I’ve discussed¬†Varroa control elsewhere, and will again.

Unfortunately, if your colony has signs of CBPV disease then Varroa control is not really relevant. The virus is transmitted from bee to bee by direct contact. This probably accounts for the appearance of the disease primarily in very strong colonies.

At the moment there’s little you can do to ‘cure’ a CBPV-afflicted colony. I hope, in 2-3 years we will have a better idea on what interventions might work. We have lots of ideas, but there are a lot of basic questions to be addressed before we can test them.

Field work

Field work

Business and pleasure

The half of my lab that don’t work on bee viruses study fundamental mechanisms of virus replication and evolution. They do this using human viruses, some of which are distant relatives of DWV. They work on human viruses as it’s only these that have excellent model systems to facilitate the types of elegant experiments we try to do. They’re also relatively easy to justify in funding applications, and it allows us to tap into a much bigger pot for funding opportunities (human health R&D costs probably total ¬£2 billion/annum, bees might be ¬£2 million/annum).

And no, my lab don’t get anything like that much per year for our research!

Importantly, the two activities on human and honey bee viruses are related. Our experience with the human viruses related to DWV made us well-qualified to tackle the bee virus. They replicate and evolve in very similar ways, we quantify them in the same way and there may be similarities in some ways we could approach to control them.

And with the bee viruses I can mix business with pleasure. If I’m going to the apiary I’ll get to see and handle bees, despite it being officially “work”. It doesn’t happen as much as I’d like as I’m usually sat behind the computer and all of the ‘bee team’ have been trained to work with bees by the ESBA.

However, at least when I talk to collaborators or to the beekeeping groups we’re fortunate to be working with we – inevitably – talk about bees.

And that’s fun¬† ūüėÄ


1¬†Several years ago I delivered an enthusiastic and rather science-heavy talk at a Bee Farmers Association meeting. I thought it had gone reasonably well and they were kind enough to say some nice things to me … and then I got the question from the back of the room which went something like¬†“That’s all very well young man … but what have you made NOW that I can put into my hives to make them healthy?”.

I’m sure my answer was a bit woolly. These days the presentation would have had a bit less science and bit more justification. We’ve also made some progress and it’s possible to now discuss practical strategies to rationally control viruses in the hive. It’s not rocket science … though some of the science it’s based on is reasonably fancy.

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Honey and hay fever

300 jars of honey

300 jars of honey

I’m conflicted.¬†As a beekeeper I appreciate offsetting the cost of indulging my hobby from honey sales. In a good year I get much more honey than I could ever give away to friends and family. Despite making some of my own equipment, there are the costs of purchasing (yet more) boxes, miticides, extraction equipment and winter feed. There’s also an ever-growing wishlist of things that, whilst not essential, would be very welcome. Abelo’s heated honey creamer looks very nice ūüėČ ¬†Bottling, labelling and then selling honey – either from the door or from local shops – provides a few quid to help … a sort of self-perpetuating process in which I transfer all that summer effort by the bees into the coffers of Thorne’s and C. Wynne Jones.

However, I regularly get asked for local honey to ‘prevent the symptoms of hay fever’. Emails or phone calls go something like this:

“My son/daughter/husband/wife suffers really badly from hay fever and I read that locally produced honey could help her symptoms” … followed by a request to confirm that what they’ve read is correct and could I sell them some honey.

As a¬†scientist I can’t do the former and so usually fail to achieve the latter. No way to run a business perhaps, but honesty is the best policy‚ąĎ.

Achoo!

Bless you

Bless you

Hay fever is an allergic reaction to pollen in the air. About 20% of the population have, or will develop, hay fever. I never had it as a child, but in my 30’s developed a strong reaction to some grass pollens that still makes a fortnight or so in mid/late June pretty miserable. Hive inspections with bad hay fever are really miserable.

Symptoms are characteristic – itchy eyes, sneezing and a runny nose (where does all that stuff come from?!). Anti-histamines, either prescription or over-the-counter, help prevent the allergic reaction from occurring. Usually this is sufficient to make the symptoms bearable.

Severe hay fever symptoms, where anti-histamines or corticosteroids are insufficient, can be treated by immunotherapy. Over several months, the patient is exposed sub-cutaneously or orally, to low and increasing doses of the allergen (the compound that causes the allergy) to help develop immunity. Full desensitisation takes about three years.

Honey contains pollen

Honey contains small amounts of pollen. The presence of the pollen forms the basis for lots of tricky questions in the BBKA examinations and is a feature used by food standards to discriminate between flavoured sugar syrup and real honey.

This is probably where the ‘honey prevents hay fever” stories originate. It’s this small amount of pollen that is supposed to stimulate the immune system of hay fever sufferers. A sort of DIY desensitisation course using toast or porridge to help deliver the allergen. Tasty ūüėČ

All this seems pretty logical and straightforward. Honey contains pollen. Low doses of pollen are used to stimulate immunity that, in turn, stops hay fever from developing. Local honey prevents hay fever¬†… I must get this printed on my labels to boost sales further.

Don’t let the facts get in the way of a good theory‚ąě

Unfortunately, there are a couple of irritating facts that scupper this nice little theory. The first is  a sort of error of omission, the second is the absence of evidence supporting the theory (or, more accurately, the evidence that the theory is wrong).

Honey certainly contains pollen. At least, real honey does. Melissopalynologists Рthose who study the pollen in honey Рcan identify the genus of plants that the bees have been visiting and so may be able to deduce the geographic origin of the honey.

The key part of that last sentence is¬†“that the bees have been visiting”. The vast majority of pollens in honey are from the flowers and trees that they visit to gather nectar. These pollens are usually large and sticky so they adhere to the passing bee and are then transferred to another plant when the bee moves on.

What’s missing are any significant quantities of pollens from wind-pollinated plants such as grasses. Studies have shown that almost all pollens that cause allergies such as hay fever are from these wind-pollinated species‚Ć. It’s logical that these pollens are largely absent … since the flowers, grasses and trees that produce them are anemophilous (wind-pollinated) they don’t need to generate nectar to attract bees, so the bees don’t visit. So there’s little or none of this type of pollen in honey.

No bees legs ...

No bees legs …

Testing, testing …

So that’s the error of omission. What about scientific support, or otherwise, for the theory that local honey prevents hay fever? After all, this must be an easy (and tasty) experiment to do. Feed a group of people honey and compare their hay fever symptoms with a group fed synthetic honey (or perhaps imported pseudo-honey sold from a supermarket near you).

Researchers in Connecticut did this experiment in 2002. They published their results in a snappily-titled paper “Effect of ingestion of honey on symptoms of rhinoconjunctivitis” published in the Annals of Allergy, Asthma and Immunology.

Rhinoconjunctivitis, or perhaps more correctly, allergic rhinoconjunctivitis, is the symptoms of hay fever – the itchy eyes, sneezing and runny nose. Three groups of a dozen hay fever sufferers, pre-screened for reactivity to common wind-borne allergens, were randomly assigned to receive local ‘raw‘ honey, filtered non-local honey and honey-flavoured syrup (the placebo group). They took one tablespoon of honey, or substitute, a day and recorded their hay fever symptoms. The abstract of the paper neatly summarises the results:

Neither honey group experienced relief from their symptoms in excess of that seen in the placebo group.

… leading the authors to conclude that:

This study does not confirm the widely held belief that honey relieves the symptoms of allergic rhinoconjunctivitis.

Absence of evidence does not mean evidence of absence

So, this study does not confirm (prove) that honey prevents hay fever. What about the opposite? Can we use it as evidence that honey does not prevent hay fever symptoms?

1934 Loch Ness haox

1934 Loch Ness hoax

Tricky … as the skeptic James Randi asserted, you can’t prove a negative. I can’t prove that the Loch Ness Monster doesn’t exist. However, in the absence of convincing evidence that it does exist, I can be reasonably sure that Nessie is a 6th Century tale, embellished in the 19th Century and blatantly exploited by the 21st Century tourist industry.

Of course, lake monsters are ‘found’ worldwide, which isn’t evidence that any of them actually exist ūüėČ

We’re getting into the messy intersection of science and philosophy here. I think it’s sufficient to say that there’s no scientific evidence that honey prevents hay fever. The Connecticut experiment was a properly controlled random study. To my mind (as a scientist) this is much more compelling evidence than any amount of anecdotal stories to the contrary.

An abbreviated version of which is what I tell potential customers who want me to confirm that buying my local honey will help alleviate their hay fever symptoms. Essentially, it won’t.

Sure, they might not get hay fever after eating my honey, but that’s almost certainly a coincidence. It’s a coincidence I’m happy to live with, but not one I’m happy to promote as a reason to buy my local honey.

Why buy local honey?

I don’t think it’s necessary to cite dubious medical benefits when encouraging people to buy local honey.

Why claim something that’s probably not true?

Far better to claim the things that are true, some of which are also clearly demonstrable:

  • It’s local, from the hedges and fields within 3 miles of the apiary. It wasn’t imported by the tonne from a location or locations unknown‚Ä°.
  • It’s a very high quality product – clearly to claim this you need to ensure it looks wonderful and that there are no legs or antennae lurking in the jar.
  • It hasn’t been excessively heated before jarring – all the goodness is still present, including pollen, just not the sort of pollen that will prevent hay fever.
  • The honey hasn’t been micro-filtered, pasteurised or tampered with in any way.
  • It varies during the season as the forage changes – a jar of spring OSR honey is very different ¬†in flavour from a jar of mid-summer floral (hedgerow) honey. It’s a wonderful edible snapshot of the changing seasons.
  • Buying it supports a local cottage industry.
  • It tastes fantastic – clearly demonstrable.

The ‘taste test’ is usually the deciding factor. A couple of tester jars – clearly labelled – a limitless supply of plastic coffee stirrers and a discard pot will allow customers ample opportunity to ‘try before they buy’.

Which they surely will … ūüôā


‚ąĎ¬†Honesty is the best policy is an idiom dating back to the late 16th Century when¬†Sir Edwin Sandys, a founder of the Virginia Company and one of the first settlers in America, stated¬†“Our grosse conceipts, who think honestie the best policie”.

‚ąě A corruption of the saying by Mark Twain “Don’t let the facts get in the way of a good story”.¬†

‚Ƭ†Jean Emberlin (2009). “Grass, tree, and weed pollen”. In Kay et al. The Scientific Basis of Allergy. Allergy and Allergic Diseases. 1:942-962. John Wiley & Sons. ISBN¬†9781444300925

‚Ä°¬†This isn’t xenophobia. The UK is a net importer of honey. 95% of the honey eaten in the UK is imported – 50% of the 34,000 tonnes imported in 2012 came from China. Most honey on the supermarket shelves contains some rather vague term like¬†Produce of EU and non-EU countries. You don’t know where it came from, and probably nor does the supermarket. There have been bans on imported honey due to it being not honey (just doctored corn syrup), or being contaminated with antibiotics.

Small cell foundation

In a recent monthly newsletter Thorne’s announced they were now supplying small cell foundation. This foundation has a cell diameter¬†of 4.9mm, rather than the standard 5.2-5.4mm. Under the¬†ambiguous heading 4.9 mm foundation for varroa control”¬†they have the following text:

Wired foundation

Wired foundation

“It is claimed varroa mites struggle to reproduce in the slightly smaller cell size. 4.9 mm being close to what bees produce in comb width in nature. Many beekeepers in the USA who have experimented with small cell have reported encouraging results. Moving over to small cell however can be difficult and must be done at the correct time of year. It cannot be done either by simply putting 10 frames of small cell foundation in the hive. The bees must first be subject to regression over a period of several months.”

Do mites struggle to reproduce?

No. There’s compelling scientific evidence that¬†Varroa levels in hives on small cell foundation may actually have¬†higher mite levels than those on standard foundation. These are from¬†properly conducted and controlled studies involving dozens of hives.

It certainly is claimed that mites struggle to reproduce in small cell foundation. The evidence actually directly contradicts these claims. Undoubtedly beekeepers in the USA have reported encouraging results, but scientists doing side-by-side comparisons clearly demonstrate that mite levels are at best not changed or at worst appreciably higher on small cell foundation.

Actually, it’s not the mites but our bees that struggle to reproduce in small cells. This explains the phrase¬†“subject to regression over a period”¬†above. You have to select smaller bees that can reproduce well in¬†small cell foundation. Once this is done, the bee size is measurably smaller and the density of brood cells in the hive is greater.

Is¬†this is a one-off study –¬†where is the independent verification?

No. They were repeated at least three times by labs at the University of Georgia. Similar studies were conducted by Florida Department of Agriculture and Consumer services. In addition, the Ruakura Research Centre in Hamilton, New Zealand, conducted their own study Рusing a different experimental format Рbut achieving the same conclusions. Small cell foundation increased mite levels when compared with conventional or standard diameter foundation. There are now several additional independent studies which essentially reach the same conclusion Рsmall cell foundation does not restrict Varroa replication and may actually increase it.

Has this new research been published?

Apidologie

Apidologie

After all, perhaps Thorne’s aren’t completely up-to-date about these studies? If the work is really new then perhaps they can be excused for¬†trying to flog something for which there’s no compelling evidence of benefit.

Well, it was¬†published … in some¬†cases seven¬†to nine¬†years ago:

  1. Taylor, M.A., Goodwin, R.M., McBrydie, H.M., Cox, H.M. (2008) The effect of honeybee worker brood cell size on Varroa destructor infestation and reproduction. Journal of Apiculture Research¬†47, 239‚Äď242 …¬†summary, a higher proportion of cells from small foundation were mite infested.
  2. Ellis, A.M., Hayes, G.W., Ellis, J.D. (2009) The efficacy of small cell foundation as a Varroa mite (Varroa destructor) control. Experimental and Applied Acarology¬†47, 311‚Äď316 … summary, no difference in mite levels between small cell and conventional foundation.
  3. Berry, J.A., Owens, W.B., Delaplane, K.S. (2010) Small-cell comb foundation does not impede Varroa¬†mite population growth in honey bee colonies. Apidologie 41, 40‚Äď44 …¬†summary, small cell colonies had ~40% higher mite infestation levels when compared with conventional foundation.
  4. Seeley, T.D., Griffin, S.R. (2011) Small-cell comb does not control Varroa mites in colonies of honeybees of European origin. Apidologie¬†42,¬†526-532 …¬†summary, no difference in mite infestation levels between small cell and conventional foundation.

If you want an accessible and readable account of small cell foundation studies Jennifer Berry has written one for Bee Culture which includes experimental details of the work in references 1-3 above.

In denial

A recent thread on Beesource discussed the reported benefits of small cell foundation and the scientific evidence that contradicts these claims. It’s notable that supporters of small cell foundation generally criticise the ‘agenda’ they claim scientists have, rather than providing scientific evidence that supports¬†the ‘benefits’.¬†I’ve not been able to find a single peer-reviewed and properly controlled study that supports the beneficial claims for small cell foundation.

Hives on small cell foundation may have manageable levels of¬†Varroa. If they do it’s in spite of the use of small cell foundation, not because of it. I am very willing to accept that there are some very competent beekeepers using splits, rational miticide treatment or other strategies¬†and small cell foundation, who have low or manageable¬†Varroa levels. However, it’s their beekeeping skill and experience not the choice of foundation size¬†that is important here.

Indeed, you could argue that the detrimental enhancement to mite reproduction of small cell foundation, means that they must have truly exceptional beekeeping talents.

Or an agenda perhaps ūüėČ

Ambiguous and misleading titles

In the opening paragraph I stated that the title¬†4.9 mm foundation for varroa control” was ambiguous. The scientific evidence presented above is that small cell foundation does control¬†Varroa. Assuming you use the word ‘control’ when defined as¬†the power to influence or direct the course of events. Small cell foundation does exert control … but almost certainly in the opposite direction to¬†the way implied in the title.

What turns an ambiguous into a misleading title is this implication that small cell foundation reduces Varroa levels. The text that accompanies makes this implication without providing any sort of balanced view based upon the published evidence to the contrary.

Beekeepers, particularly beginners, looking for effective ways to reduce their mite levels are not being provided with the facts and are likely to be misled.

But wait … were all these scientific studies flawed?

Thorne’s partly justify the sale of small cell foundation in their newsletter by citing a UK research project that involves its use:

“The University of Reading has just started an exciting new research project examining the highly problematic issue of varroa mites and whether the use of small cell foundation (4.9 mm) can help. This is being carried out with volunteer beekeepers in the local area as well as in an apiary at the University. The study will evaluate the use of small cell foundation alongside regular-sized (5.4mm) foundation and compare the varroa loads during next spring and summer.

This is an interesting topic to research as beekeepers around the world have had success with the use of small cell foundation whereas many others have not. Some previous studies have also found that varroa counts increase in the short term when small cell foundation is first used. The new study will evaluate what happens once the bees have fully adjusted to small cell foundation and if there is a significant impact on varroa loads.”

The implication here is that the previous studies (above) are flawed because they failed to use bees that were properly adapted to small cell foundation. Thorne’s do clearly state that the bees have to be properly adapted – subjected to regression – for several months before benefits are seen (or claimed to be seen). To their credit also, they acknowledge that some studies show increases in mite levels. This text is from the newsletter and unfortunately does not appear on the webpage of their catalogue that describes the foundation.

Call me sceptical …

If it looks like a duck ...

If it looks like a duck …

As you can tell from the tone of this post, I remain sceptical.

If it looks like a duck, if it swims like a duck and if it quacks¬†like a duck … it is a duck. As a scientist I’m influenced by controlled studies, not hearsay or beliefs.

The Berry study (ref 3 above) did use bees reared on small cell foundation for their comparative studies, the other studies did not as far as I can tell.¬†However, remember the original hypothesis about why small cell foundation is beneficial. The mites do not develop properly within the cell as they are ‘crowded’ by the abdomen of the developing honey bee pupa i.e. there’s too little space for the mite.

What does regression lead to? Smaller bees. In the Berry¬†et al., study the weights of adult bees reared on small cell and conventional foundation was 129 and 141 mg respectively. This seems to be contradictory … if properly regressed bees on small cell foundation are significantly smaller than those on conventional foundation how is the space for the mite development restricted? I acknowledge that the cell size is proportionately smaller than the reduction in adult bee weight.¬†Conversely, if small cell foundation is supposed to restrict mite development, why are levels apparently higher when ‘normal’ sized bees are first forced to use smaller cells? Surely there should be a greater reduction in mite reproduction before the bees have regressed?

I hope the study being conducted by the University of Reading is thorough and properly controlled. These are difficult studies to conduct, particularly at the scale needed to be statistically convincing and when not under the direct control of a single beekeeper in a single apiary. I wish them every success with the experiments and look forward to reading about it once it is peer-reviewed and published.

Until then I suggest you save your ¬£11.60 for ten sheets of small cell wired brood foundation … you’d be far better off preparing foundationless frames and controlling¬†Varroa by rational and judicious use of hive manipulations and approved miticides.


Additional reading (far from exhaustive):

The late and still unbeatable Dave Cushman has an article by Philip Denwood reproduced from the 2003 BIBBA magazine on cell size. Recommended for a historical perspective.

A 2013 article from the New Hampsha’ Bees blog¬†Small cell doesn’t work (but please don’t tell my bees describing typical¬†evidence that small cell foundation does work¬†… anecdotal and not controlled, but nevertheless enthusiastic and – unusually – acknowledging the evidence against.

Michael Bush on small cell bees and foundation.

Dee Lusby – one of the originators of the ‘small cell’ movement – in an early article from ABJ reproduced on the Beesource forums. Be warned … there’s some misleading¬†nonsense in this article.¬†For example¬†“it is a known fact that both honey bees and mites have been on this Earth many millions of years together and survived quite nicely”.¬†I don’t disagree that both mites and bees have been around for millennia. However, they have only been together for a century or so. I think I’ll have to write something about natural beekeeping in the future …

It’s notable that top Google ‘hits’ for small cell foundation provide no scientific support for the claims that are made¬†… caveat emptor.

 

 

 

You’ve spilt wax in the kitchen … again

cover_natureThere’s an interesting article in yesterday’s¬†Nature on the detection of beeswax residues in crockery shards dating back at least¬†9000 years i.e. since the development of agriculture.¬†This suggests that humans have been exploiting bees and bee products since the Neolithic Revolution when the first animals were domesticated, though evidence for beekeeping (from wall engravings in Egypt) only exists for about 4500 years. Samples of crockery almost 6000 years old from Southern/Eastern England¬†were found containing traces of wax, but more northerly samples were free from residues. This suggests that there was a northerly/westerly ecological limit to the distribution of honeybees (Apis mellifera) but confirming – assuming Neolithic pastoralists weren’t plagued with imports – that honeybees aren’t a recent introduction to the British Isles.

YBKA Spring Conference

York College

York College

I’m delighted to be talking ¬†– twice (!) – at the Yorkshire Beekeepers Association Spring Conference in York on Saturday. With Stephen Martin (bee recognition and the Asian hornet), Jay Evans (beenomics – is that a real word?), Ben Jones (nutrition) and Liz Collison (neonicotinoids) also on the programme it promises to be an enjoyable day.

Update – it was a very enjoyable meeting and I’d like to thank the YBKA, Roger Chappel and Michael Badger for their excellent hospitality. My talk on queenright queen rearing using the Ben Harden system was well attended and generated some interesting questions. Abelo had a small trade stand selling all sorts of ‘essentials’ including some competitively priced radial extractors.