Socially distanced bees

A real skill when writing scientific papers 1 is to give them a suitable title.

Choosing the title involves a combination of art and science.

It must look appealing … you want the viewer to become a reader.

Since it is always indexed by search engines you must make sure it includes suitable keywords or phrases.

It needs to be informative. At least sufficiently so that the ‘take home message’ is clear. Even if the viewer does not become a reader they should still remember the title and so know the gist of what the article concludes.

The art of good title writing goes beyond this though. To increase the appeal, if it includes humour, some sort of half-hidden pun or some clever word play, then all the better.

And there are some great examples out there:

  • You probably think this paper’s about you: narcissists’ perceptions of their personality and reputation by Erika Carlson et al. (2011) in Journal of personality and social psychology 101:185-201. doi:10.1037/a0023781
  • Fifty ways to love your lever: Myosin Motors by Steven Block (1996) in Cell 87:151-157 https://doi.org/10.1016/S0092-8674(00)81332-X

There’s another variant of the latter and a host of additional variously funny or insensitive titles in this post on Slate. This also includes mention of the contrived efforts some scientists make to include Bob Dylan song titles in their publications (see Freewheelin’ scientists: citing Bob Dylan in the biomedical literature in the BMJ) as part of a long-running bet with colleagues.

Making it topical

Failing humour – and you could argue that some of the examples above 2 or linked are failing humour – a good way to get a paper some attention is to use a title that overtly hints at topicality.

In this regard, two papers caught my eye 3 this week:

The first of these is topical because travel restrictions to limit infectious disease transmission is a near-daily news item. However, it goes further than that in also including the Blofeld-like quote. The paper also has an entertaining abstract which finishes with the words We only live once, and sub-sections entitled The man with the golden gut: food safety and infections and The fly who loved me: arthropod-borne diseases. 

However, I’m not going to discuss the analysis of Bond’s hand-washing, potential Toxoplasmosis or the disturbingly high mortality rate of his sexual partners.

You’ve seen the film(s), now read the book paper 😉

Instead I’ll briefly focus on the second paper which managed to sneak ‘social distancing’ into the title, thereby ensuring it was picked up by almost every newspaper in the UK.

Socially distanced bees

‘Briefly’ because it’s a long paper and because rather too many of the figures are uninspiring bar charts like this one:

Spatial shift in allogrooming behaviour

… which, if you read the legend shows that there is almost no significant (ns) difference in allogrooming behaviour (which I’ll come to shortly) between Varroa-infested and -uninfested bees.

However, some of the graphs do have bars of different heights (and that are statistically significantly different) and there’s an interesting contradiction between studies conducted on full colonies and individual cohorts of bees.

So, rather than work through the entire paper I’m going to just focus on a few points and then discuss a couple of things that I found interesting.

Hypothesis driven science

Social insects, like ants and bees, are particularly at risk from pathogens and parasites. Their large populations, high density and ample food reserves means they have had to evolve both individual and social immunity.

The former prevents or mitigates infection of the individual, the latter reduces the chances that the colony will get infested (or restricts the impact of any infestation or infection to help ensure the survival of the colony).

The authors hypothesised that the presence of Varroa might induce some of these social immune responses. For example, bees might increase grooming activity in areas of the hive where Varroa were most frequent, or they might decrease antennation or trophallaxis with infested nest-mates, all to reduce the chance of mite transmission.

They focused on two particular aspects of social immunity and colony organisation, and made two predictions (hypotheses) for each:

  1. Space usage.
    1. Spatial shift of waggle dances to the periphery of the brood nest in infested colonies when compared with uninfested colonies.
    2. Spatial shift of grooming activity to the core of the colony in infested colonies when compared with uninfested colonies.
  2. Social behaviour.
    1. Infested bees would be expected to show changes in social behaviour including an increase in allogrooming, and decreases in antennation and trophallaxis.
    2. Changes in the structure of the social network in the infested hive, with decreases in connectivity and centrality.

Using colonies with high and low (almost negligible – I’ll return to this later) mite levels they then conducted observational science – they watched waggle dances, allogrooming etc. – to see if their predictions were correct.

Compartmentalisation of the colony 

When we open a hive all we often see is a mass of bees covering every frame.

Lots of bees

Beekeepers are often too busy trying to find the queen, or judge whether there are eggs or sufficient stores present, to appreciate that the bees are organised into two main ‘compartments’ within the colony:

  • an outer one occupied by foragers (the older bees) located nearer the hive entrance.
  • an inner one containing the young nurse bees and the queen, all of which are mainly arranged on brood.

The authors reasoned that since foragers represent a potential entry route of Varroa into the hive, you might expect the waggle dancing foragers to move the ‘dance floor’ to the periphery of the colony.

Does this make sense to you? To me it only really makes sense if you assume that the forager picks up a mite from elsewhere, for example when robbing a mite-infested collapsing colony elsewhere and returning to the hive. The alternative is that that forager was already carrying a mite, though I suppose that’s still a mite being introduced (or, more correctly, reintroduced) to the colony

Whatever the reason – and this wasn’t really elaborated – the changes in space usage and social behaviour would be expected to increase the compartmentalisation of infested colonies, so reducing mite spread.

Remember, mites predominantly associate with nurse bees and need to spend several days ‘surfing’ around the colony on these bees before entering a cell to reproduce.

Experimental details

Two month before the experiments started observation hives and other colonies were treated with dribbled oxalic acid. The colonies destined to be “Varroa-free” were then treated once a week for two further weeks with trickled oxalic acid.

Six weeks later, at the start of the observations, Varroa levels were strikingly different. The infested colonies were about ~6.2% and the “Varroa-free” uninfested colonies ~0.1%.

6% means six mites for every 100 bees sampled.

The team recorded the location of waggle dances and allogrooming in observation hives. Independently, using individually marked populations of caged bees, they recorded allogrooming, antennation and trophallaxis.

And, just so we all know what these terms mean:

  • allogrooming – is where one bee removes foreign particles and parasites from another bee
  • antennation – is how bees identify nestmates in the hive, by touching with the antenna
  • trophallaxis – is where one bee feeds another bee liquid food

Spatial shifts in waggle dancing and allogrooming

The colony is approximately spherical, sliced through by the vertically-hanging frames. The authors distinguished between the central frames and the lateral frames, and the position on the frames being closer or further away from the hive entrance 4.

In uninfested colonies the waggle dance and allogrooming activity occurred on both central and lateral frames, and predominantly on the lower half of the frame.

In contrast, infested colonies showed a significant shift of waggle dancing activity to lateral frames, and to positions closer to the hive entrance on these lateral frames. The allogrooming activity also shifted, but in the opposite direction, becoming concentrated on a larger area of the central frame.

These spatial changes were statistically significant and they should have the effect of keeping the forager and nurse bee populations better separated, and of concentrating the grooming activity to the centre of the colony.

Spatial organisation of nurse bees (yellow) and foragers (red) in mite-infested and uninfested colonies

Did the latter occur because that’s where most of the mites are located … hanging around waiting for a suitably-aged late stage larva to snuggle up with?

Or, does allogrooming become concentrated in the core because the nurse bees – which are responsible for most allogrooming activity – have relocated from other areas within the colony?

Or both? … these are not mutually exclusive.

The diagram above is my half-assed rather poor attempt to demonstrate the changes in compartmentalisation within the colony. In the colony on the left there is much more mixing and overlap between the nurse and forager bees. On the right there is much less mixing, and therefore less opportunities for mite transmission.

Social behaviour

The studies on social behaviour were somewhat less definitive, or produced unexpected results. These studies were all done using caged bees from infested or uninfested colonies. Allogrooming, antennation and trophallaxis can all be divided into ‘giving’ and ‘receiving’ activity, all of which was recorded, as was whether the bee from the infested colony was activity carrying a mite.

The expectation was that these activities – all of which are likely to increase the opportunities for mite transmission – might all be reduced in bees from Varroa-infested colonies, with one or two caveats.

In fact, in the majority of cases there were no significant differences between the levels of allogrooming, antennation and trophallaxis.

The exceptions included Varroa-parasitised bees which were – perhaps understandably – more likely to be the recipients of grooming.

Infested colonies overall exhibited slightly increased antennation, with Varroa-carrying bees receiving significantly more attention from cage-mates and – in turn – performing less antennation.

Finally, although there was no overall difference between trophallaxis between bees from infested and uninfested colonies, bees actively parasitised by Varroa received more trophallaxis … an unexpected result considering the potential for mite spread.

The final hypothesis that was tested was whether the social network changed in infested colonies. This was based upon analysis of high resolution videos of caged bees, recording the interactions between and then calculating the connectivity and centrality of the network.

I’m deliberately being brief in my description of the methodology here, for two reasons; 1) it’s complicated and would take 500 words to describe more fully, and 2) there were no differences in the measured parameters of the social network in the infested bees when compared with the bees from the uninfested colonies.

Contradictions

Looking back at the predictions (see above) it seems clear that there were large scale changes in space usage within the colony … perhaps justifying the phrase ‘social distancing’ in the title.

However, when the authors looked at individual cohorts of bees they did not detect evidence of increased small scale separation – either within the social network they formed, or in terms of avoiding activities that would be expected to lead to mite transmission.

In fact, the caged bees showed increases in activities that were commensurate with ‘care giving’ … increased grooming and trophallaxis of Varroa-carrying individuals.

These appear to be contradictory observations.

How can the large scale spatial reorganisation occur without changes in the bee-to-bee interaction that occurs at a smaller scale?

The authors skirt around this a little, but don’t really tackle it head on.

Loose ends

I think a couple of things warrant further investigation.

The large scale spatial reorganisation was of activities (dancing and grooming) not of bees, though there was an unwritten assumption that the activities were observed to move because they were conducted by particular ages of bees (which did move).

That could be tested by high resolution video observations of a colony containing marked cohorts of nurse bees and foragers. The expectation would be that – like the red and yellow circles I’ve drawn above – you would expect to see a more distinct separation of the two groups.

With sufficient time, money and video recording you could also use this in place of the studies of small cohorts of caged bees. For example, using lots of bar coded bees. Perhaps these don’t perform in the same way outside the hive as inside it?

Oxalic acid treatment

The authors used oxalic acid to reduce mite levels in the “Varroa-free” hives.

Unusually – at least in my experience – they used three weekly treatments of trickled oxalic acid.

This seems to have been very effective in reducing mite levels – compare the 3 x treated (0.1% infestation) to the 1 x treated (>6% infestation) – five to eight weeks respectively after the treatment started.

I was surprised it was that effective in a colony that was activity rearing brood, where the majority of the mites would be hidden in capped cells.

However, there are numerous studies that show that trickled/dribbled oxalic acid damages open brood 5. Therefore, in the studies conducted in this social distancing paper there’s a possibility that an entire generation of brood were missing due to the three successive treatments with trickled oxalic acid.

How this would have affected the results is unclear.

Although bees display temporal polyethism they also exhibit developmental plasticity and can change roles if and when needed. This doesn’t appear to have been considered and is certainly not discussed in the paper.

How is social distancing achieved?

But, let’s take their clever and topical title at face value and accept that bees do socially distance in response to mite infestation 6.

What level of mite infestation is needed to initiate this activity?

What are the molecular (chemical) or behavioural signals that trigger this activity?

Can we, as beekeepers, exploit them to improve the efficacy of rational mite management?

All of which will involve wild speculation and precious few hard facts, so I’ll save it for another time 😉


 

Measure twice, cut once

Swear often 😉

I’ll return to cursing shortly … bear with me.

The autumn solstice is long gone and we’re fast approaching the end of British Summer Time 1. For most northern hemisphere beekeepers this means that there may be five months of ‘not beekeeping’ before we start all over again.

Of course, there are things we have to do with the bees in the intervening period.

The hive entrances must be kept clear so they can get out on the inoffensively named ‘cleansing flights’ when needed. There will be a winter miticide treatment to apply … probably long before midwinter. It is also important to keep an eye on the weight of the hive – particularly as brood rearing starts in earnest in late January and February – to ensure the bees do not starve.

But those three things aren’t going to fill anything like five months, so there is bound to be some time ‘spare’ over the coming months.

The elasticity of time

Although the year contains twelve about equal length months, those of us who keep bees in temperate northern countries experience a strangely warped calendar.

This is what it feels like … the beekeepers year

Apparently the months only vary in length by ±3 days. May and December contain the same number of days, but May disappears in the blink of an eye, whereas December can drag on interminably.

Weirdly there appears to be an inverse relationship between the available daylight to work in, and the amount of time it feels as though you have available to actually get the various beekeeping tasks completed.

This surely defies the laws of physics?

All of which means that beekeepers often have little free time in the summer and ample free time in the winter.

Some wise beekeepers have a busman’s holiday and go to New Zealand to tour apiaries (and – more to the point – vineyards).

Others catch up with all of the non-beekeeping activities that apparently ‘normal’ people do … like the decorating, or building model railways, or flamenco dancing 2.

Getting creative

But if you still want to dabble with a bit of beekeeping – in the broadest sense of the word –  through the cold, dark days of December and January 3 there are all sorts of things you can do. 

Many years ago I wrote an irregular column for my then beekeeping association on do-it-yourself (DIY) for beekeepers.

It was irregular because my use of punctuation has always, been suspect, and because it didn’t appear each month. 

That column eventually morphed into this website 4.

In fact, some of the very earliest articles were almost lifted verbatim from the beekeeping monthly newsletter.

I wrote about DIY because it was something that:

  • brought me a lot of satisfaction
  • saved me a few quid
  • improved my beekeeping

Now, a decade or more later, I still use the winter months to do the majority of my beekeeping-related DIY 5.

It’s only in the winter that I have the time to think things through properly before rummaging through the wood offcuts box and actually building something.

Measure twice, cut once

Which brings me back to the start of this post.

The motto for beekeeping DIY could be something like:

Measure twice, cut once, swear often 6

However, having identified a problem, there’s almost as much enjoyment to be gained from thinking it through to a workable solution than there is from the actual woodwork.

But Think lots, measure twice, cut once etc. doesn’t have quite the same flow.

And, as we’ll see below, it doesn’t have to be woodwork.

So I can happily fill a few hours on a dark November evening thinking about improvements to a hive stand that could cope with 1500 mm of rain a year and very uneven ground 7, or how to best construct the removable slides for a Morris board.

And by best here, I mean for a lot less than the £30 charged for the commercial ones 8.

Morris board … that’s £8.25 please

Part of the thinking involves how to tackle the project with the limited range of tools I have. I don’t have the space or the skill 9 to own a bandsaw, or a thicknesser 10, or a router.

Almost everything I build uses a combination of Gorilla glue, Correx, hand tools, blood 11, wood offcuts and some really rich Anglo-Saxon phrases.

My DIY skills are legendary, and not in a good way, but the great thing is that the bees could not care less

Fat dummies

Most of the various things I build develop from ideas that occur during the ‘active’ beekeeping season.

If it’s needed urgently I’ll cobble something crudely together and use it there and then. However, it’s unlikely to have received much thought (or care in construction) and so I’m more than likely to ponder how it could be improved once I have a bit more time.

I learnt the basics of queen rearing from the late Terry Clare at a BBKA Annual Convention and couldn’t wait to have a go myself.

Fat dummies – mark 1

I used the Ben Harden queenright queen rearing approach. This needs an upper brood box with most of the space ‘dummied down’ to concentrate the bees on the grafted larvae. For this you need a couple of ‘fat dummies’ 12. I built my first fat dummies one afternoon using gaffer tape and Correx (see above) and later that April reared my first queens.

But that winter I had time to do a bit more research. Dave Cushman’s website described fat dummies with integral feeders.

Clever.

These would clearly be an improvement – unless there’s a strong nectar flow you often have to feed the colony – so I built some. 

Fat dummy with integral feeder

Fat dummy mark 2 … with integral feeder and insulation

Mine are still in use … and not just for queen rearing. They are packed with polystyrene insulation … an embellishment I thought up 13. I can use them to reduce ’empty’ space in a brood box occupied by an undersized colony. In fact, with two of them, I can overwinter a four-frame nuc over a strong colony to provide warmth from below.

Problem solving

As I said earlier, the problem solving is part of the fun. 

I use a lot of Correx. That’s the fluted polypropylene board that is used for political posters and For Sale signs.

Sourcing it is often not a problem if you’re prepared to do some homework.

It’s lightweight, strong, available in a range of cheery colours … but most importantly it is used for political posters and For Sale signs.

So, it’s often free.

And that’s a word all beekeepers like 😉

Wait for a general election and seek out a candidate who has suffered an ignominious and humiliating defeat. Ideally one in which they have both lost their deposit and and any remnants of support from the political party they were standing for … and ask politely.

And For Sale signs are even more easily obtained. Always ask … and remember that it’s bad form to remove them if the house has yet to be sold.

But there’s a problem with Correx. You cannot glue it with any normal glues. It’s got some sort of surface coating that prevents glue from adhering properly. 

Believe me, I’ve tried.

There are special glues, but at special prices 🙁

Roofs

I wanted to build some hive roofs from Correx but had to solve how to fold it ‘across’ the longitudinal flutes, and then how to stick it together in a way that would be weatherproof.

Pizza cutter

Pizza cutter … take care scoring the Correx

The folding bit was easy … it turns out that people who keep guinea pigs use this stuff to make the cages and runs for their cavies. And after an hour or two reading about someone else’s (weird) obsession I discovered that a pizza cutter was ideal for scoring Correx prior to folding it.

The glue I worked out for myself. I built a couple of dummy roofs and held the folded corners together with zip ties or regular gaffer tape, zip ties and regular gaffer tape, or some (claimed) waterproof tape.

Of these, the waterproof tape – specifically Unibond Extra Strong Power tape – worked really well. 

Sticky stuff ...

Sticky stuff …

And remains the only one I’ve found to work.

You need to lightly sand the surface of the Correx and ideally degrease it with some solvent. I still have roofs built 8 years ago with the original tape holding them together. They cost me £1.50 each to build as I had to buy 14 the Correx as the only For Sale signs I had were too small.

Here’s one I made earlier

Most of the things I’ve made have been through one or two iterations of ‘improvement’ before I’ve ended up with something I’m satisfied with.

The Kewl floors I almost exclusively use these days were an improvement of the original design I built, but have also had a couple of additional modifications

My honey warming cabinet – one of the first things I ever built – was modified after a few years by the addition of a fan to better circulate the warmed air. This significantly improved it.

The things I’ve discussed above are all good examples of why it’s worth spending some time in the winter doing some creative thinking and DIY 15 :

  • commercial Morris boards are expensive and (I think) have entrances that are too large
  • I’m not aware of any commercially available fat dummies … please correct me if I’m wrong
  • no one sells hive roofs (or super carrying trays) for £1.50
  • my floors are ideal for the beekeeping I do and significantly less expensive than anything similar available commercially
  • my honey warming cabinet is used to warm supers before extraction, to melt set honey and – because the temperature control and heat distribution is good enough – has even been used as a queen cell incubator

Electrickery

This winter I have three projects to entertain me.

The first project is the second iteration of my DIY portable queen cell incubator. The first of these was cobbled together earlier this year. Although it worked – more or less – it was far from satisfactory.

Mark 2 is currently being stress tested.

It is being tested.

I am getting stressed.

Queen cell incubator – mark 2 … a work in progress

I’ve managed to achieve really good temperature control. However, I’m currently struggling with uneven temperatures at different areas within the box. They barely fluctuate, but they’re not the same.

Great temperature control at a range of (different) temperatures

Grrrr.

I’m pretty sure this is solvable 16 and that it will be possible to build something better than is available commercially for about 10-15% of the price 17.

But, almost more important than that, it will be a problem I’ve solved 18 that suits me, my bees and my beekeeping … which will be very satisfying.

The second project is a set of hive scales. Lots of others have tackled this problem and there are some really clever and complicated solutions out there.

The plan is for mine to be the exact opposite.

Simple, and not very clever at all.

Testing is ongoing 😉

Software, not hardware

And the final project is software, not hardware.

All my honey jars have unique batch numbers. These allow the individual apiary (and bucket) to be identified. The batch number is generated by some PHP or perl scripts and used to print a QR code onto a Dymo label affixed to the back of the jar.

QR code containing a batch number

But that monochrome pointillist pattern contains a hidden web address as well. The purchaser will be able to point a mobile phone at the code and get more information about the honey 19

Having sold honey ‘from the door’ for years I’m unsurprised when buyers want to know more about local bees and the available forage … and with these labels they can (and do).

I’ve written the scripts to handle label creation and logging/redirecting ‘views’. I now have to write the programs that create the customised web pages with the local information lifted from the backend database.

And, with only ~165 days until I next expect to open a hive, I think I’m going to have my work cut out to complete any of these projects.


 

Autumn cleaning

Over the last fortnight, despite some occasional warm and sunny days, the autumn has made its presence known. 

Flaming autumn aspen

The aspen down the road are a stunning colour at this time of the year. Although I’ve planted a couple of dozen, they’re still not more than thigh-high and it will be quite a few years until they can match the display shown above.

Almost overnight hundreds of redwing have arrived from Scandinavia and many of the rowan have already been stripped bare 1.

In Fife, the leaden skies are filled with skeins of geese forming raggedy V’s as they fly in from the North Sea. It’s an evocative sight … it reminds me of my first weeks as an undergraduate student at Dundee University half a lifetime ago

And it also emphasises that the beekeeping season is over.

Of course, there will be jobs to do in the winter, but the bees are pretty much on their own for at least the next five months.

Apivar

The final essential task of the season for me is to remove the Apivar strips that went into the hives in August. Initially the strips were placed on either side of the – still large – brood nest. A few weeks ago I removed the strips, scraped them free of propolis and wax and re-inserted them around the, now shrunken, brood nest.

Mid-autumn and time for the Apivar strips to be removed

You can just about see them in the photo above, flanking the four central frames.

It is important to remove the strips. Although Apivar has a relatively short half-life, some residual activity will remain. If you leave them in the hive any surviving Varroa – and there will be survivors 2 – will continue to reproduce in the presence of trace levels of amitraz, the active ingredient in Apivar. 

With reduced – and possibly borderline for killing – levels of amitraz present, these are ideal conditions in which resistance may develop. Although this has been reported it does not appear to be widespread. 

Therefore, to ensure that Apivar remains an effective miticide it is important to remove any remaining strips before the winter.

Your next adventure in Glenrothes awaits!

Tragic isn’t it?

That’s the subject line on the emails I receive from Travelodge where I stay when I’m doing my beekeeping in Fife. 

Have you ever been to Glenrothes?

‘Adventure’ isn’t the word most people associate with Glenrothes. 

Good morning Glenrothes

GetMeOuttaHere is. 

This is a town where every third car being driven late at night has a raucous exhaust, lowered shocks, tinted windows and a spoiler. The drive-in queue for McDonald’s sounds like the pit lane at the Indianapolis 500 and there are more donuts in the car park than in the fast food outlets 3.

But none of that usually bothers me as, by the time I get to the hotel, I’ll have been driving for 5 hours and will have spent about the same amount of time inspecting colonies or lifting cleared supers. I may also have squeezed in a couple of hours of meetings at work.

The environment might be noisy, but the beds are comfortable. 

But visits in late autumn are a bit different.

No colonies to inspect, no grafting to do, no nucs to check for mated queens and no supers to remove.

All I need to do is gently lift a few crownboards and pull out the Apivar strips now that treatment is complete.

So, what do I do for the rest of the day?

Long range weather forecasting

Is that an oxymoron?

I book my trips to Fife to fit in with what the bees need. To make the hotel affordable I book many weeks in advance.

I therefore put up with whatever the weather throws at me. Usually it works out OK.

Furthermore, as regular reader know, several hives are in a bee shed, so the weather is largely irrelevant.

But ~60% of them are outside.

And Monday was really wet. 

Having driven for four hours through increasingly heavy rain – stopping en route to make a honey delivery – I fortified myself with a cappuccino and excellent almond croissant from Taste, the best independent coffee shop in St Andrews 4.

Essential fortifications

I then sat in the shed enjoying my late breakfast listening to the rain hammering on the roof.

I needed something to occupy me until either:

  • the rain stopped
  • it got so late in the day that I’d just have to open the hives and remove the strips anyway

And the obvious thing to do was a bit of spring autumn cleaning. 

During the season the bee shed is used on a daily or weekly basis depending upon the experiments underway. In addition, we have a storage shed on the same site and a number of additional hives in the same apiary. I also do most of my queen rearing in this apiary (the bee shed provides a near-perfect environment for grafting), distributing the nucs to other apiaries for mating.

And all that beekeeping tends to leave a bit of a mess. At least, it does where I’m involved.

Super job

For the last couple of years I’ve not bothered returning the extracted supers to the hives for the bees to recover the last of the honey.

Instead I’ve just stacked them ‘wet’ in the shed, protected from wasps, mice and robbing bees, by covering the top of the stack with a well-fitting roof.

Or a snug-fitting crownboard and a badly fitting roof.

Stacked ‘wet’ supers

Experience has taught me that the floor of the shed isn’t level and/or has gaps between the planking. Rather than seal all these gaps I simply stand the stack of boxes on the sort of closed cell foam sheeting used for packing furniture, or – when I run out – on double thicknesses of cardboard 5. This stops the wasps, ants and bees from getting access. 

So I started by tidying the stacks of supers. Inevitably this necessitated moving them first, sweeping the floor clean, laying out the foam/cardboard and then restacking them. There’s not enough space in the shed to move ~60 supers so they went out in the rain.

So I got wet 🙁

Floors, roofs, boards, unidentifiable objects and wax moth

Once they were back I could turn my attention to the other side of the storage shed which houses spare roofs, nuc feeders, floors, boards (split, crown, surf, Morris, Snelgrove etc. 6 ), a breeding colony of queen excluders 7 and a motley collection of other items that:

  • might come in useful
  • don’t logically belong anywhere else
  • appear valuable and/or difficult to make … but I don’t know what they are
  • are essential and were needed several times in the season … but I’d lost them 🙁

Sorting this lot out took another hour or two, and involved a further soaking as I needed to clear the space before I could refill the space.

Early on in the process … 

Is beekeeping the largest volume hobby?

… and when at least partial order had been restored …

Floors from Abelo, Pete Little and some homemade abominations

I also found several brood boxes full of drawn comb or sealed stores.

Excellent 🙂

And I found a nuc box lurking in the far corner containing comb riddled with wax moth 🙁

Wax moth larvae and damage

Aargh!

DiPel DF

Wax moth are something I’ve largely avoided or ignored for most of the last decade. The cold winters in Scotland seem to keep their numbers down.

Not this time … 

All of the infested frames were bagged up for burning at the earliest opportunity. The remaining brood frames were treated with DiPel DF, a suspension of Bacillus thuringiensis kustaki spores and toxins. If ingested by the larvae of wax moths, the δ-endotoxin component dissolves in the alkaline environment of the gut, is activated following cleavage by gut proteases and then ‘punches’ a hole through the gut wall.

Ouch.

And the spores germinate, allowing the bacteria to grow inside the larva.

As I wrote in a post several years ago about this treatment:

This isn’t good for the moth larva. Not good at all. Actually, it’s probably a rather grisly end for the moth but, having seen the damage they can do to stored comb, my sympathy is rather limited.

DiPel DF is non-toxic for bees.

DiPel DF

I’ve not had problems with wax moth infesting supers stored ‘wet’ … they’re after the old cocoons and other rubbish that accumulates in brood frames.

Vita used to sell a product called B401 – also a suspension of Bacillus thuringiensis spores and proteins – which was withdrawn from sale in 2019. Despite assurances that a replacement – imaginatively labelled B402 – would be available ‘soon’ it appears to only currently be sold in the US.

Out with the old … and the not fit for purpose

I was on a roll … 

All this organisation meant I discovered things that I’d lost … like a small stack of contact feeders hiding in the corner that had not been used this season as I hadn’t done any shook swarms.

There they are! Contact feeders lurking shyly in the furthest corner (unlike those brazen frame feeders at the front)

I also found some mini-nucs I’d built for queen mating almost 10 years ago. They were made of ply and housed a tri-fold full-size brood frame (you can now buy these, but couldn’t when I built them). 

Tri-fold brood frame

However, the ply was starting to delaminate and it was pretty clear that they wouldn’t survive a Scottish summer season so they were unceremoniously binned.

And I finally bit the bullet and got rid of all my XP Plus queen excluders. These were bought from Thorne’s a few years ago and had been used only when I ran out of everything else.

In principle they are a good idea. A white plastic queen excluder with bee space on the underside provided by a raised rim and a series of small X-shaped spacers that stand on the top bars.

XP Plus queen excluder (the plus must mean ‘plus warp’)

However, in practice, they’re rubbish. They were the ‘ugly’ in my 2017 description of queen excluders that included the phrase ‘the good, the bad and the ugly’.  

They warp really badly. The photo above – if anything – obscures the warp because the QE is not being held flat. When you place them under a super the centre bows up and contacts the underside of the super frames.

Rubbish. 

Out they went.

The little things

There’s something rather poignant about the death throes of the beekeeping season. It can end with a bang as autumn storms roll in, or it can end in a protracted stutter as intermittent good days allow the bees to forage late into October. 

Of course, it’s au revoir 8 and not a final goodbye

It forms such a large part of my life for six months of the year that little things found during the clear-out bring back a flood of memories …

Nicot cup and (partly squidged) queen cell amongst the debris on the shed floor

A Nicot cup and vacated queen cell reminded me what a good queen rearing season we’d had on the east coast. Although the first round of grafting was a near-total failure, successive rounds were excellent, and queen mating was very successful. One of the best seasons in memory 9.

Coffee stirrer … or AFB test kit

Not all the memories were good ones though. I received one of the dreaded ‘AFB alert’ warnings for the apiary and spent a very long couple of days checking every cell on every brood frame in every colony, and testing any that looked suspicious.

I don’t take sugar, and the coffee stirrer shown above is provided in the AFB LFD kit to lift the dodgy-looking larva into a tube for analysis. Everything looked clear, but it gave me a few very stressful days.

And … after all that tidying, and repeated trips to the industrial-scale bins, it finally stopped raining.

Finally … some practical beekeeping

I fired up the smoker and quickly, but gently, removed all the Apivar strips. The crownboards on all the hives were very firmly stuck down with propolis and the bees, although calm, weren’t exactly overjoyed to see me.

Autumn still life – smoker, hive tool, Varroa trays and Apivar strips

I still had another apiary to visit. With rain threatening there wasn’t time to monitor the level of brood present so I slipped cleaned Varroa trays under the hives. This will allow me to inspect both residual mite drop and look for the presence of the characteristic biscuit-coloured cappings when brood is uncapped.

And then, after about half an hour of practical beekeeping, I set off back to the west coast as the rain started again.

The Moidart hills – An Stac, Rois-Bheinn and Sgùrr na Ba Glaise

Two days later the Moidart hills had their first dusting of snow.

It’s official, autumn is here and the beekeeping season is over.


 

Dancing in the City

Beekeeping is an increasingly popular pastime. Since ~84% of the UK population live in urban areas (up from ~70% in 1950’s) it is not unsurprising that the number of hives kept in cities is increasing.

Of course, not everyone who lives in a town or city keeps their bees in the back garden. When I lived in the Midlands I lived on a small estate that was indisputably ‘urban’, although there was farmland within sight 1. My bees were on the nearby farmland and I just kept a few mating nucs and a bait hive in the back garden 2

Hive in a field margin

I kept my bees in the farmland because 3 I reasoned that there were both larger amounts and a greater range of forage available for them there.

But I was probably wrong.

It wouldn’t be the first time, and it certainly won’t be the last.

Too many bees?

Before discussing urban bees and forage in more detail I’ll digress a minute to mention the suggestions that the inexorable rise and rise of urban beekeeping is threatening our native pollinators.

Actually … more than suggestions.

There are a number of scientific reports and reviews that indicate that urban beekeeping harms – by outcompeting – native pollinators like solitary bees. A recent report by the Royal Botanic Gardens at Kew states:

‘Campaigns encouraging people to save bees have resulted in an unsustainable proliferation in urban beekeeping. This approach only saves one species of bee, the honeybee, with no regard for how honeybees interact with other, native species.’

‘In some places, such as London, so many people have established urban hives that the honeybee populations are threatening other bee species.’

Our bees (Apis mellifera) are generalists. They are not particularly well adapted to any flower or nectar/pollen source.

They are equal opportunists.

Individually, there are many solitary bee species or non-hymenopteran pollinators, that are ‘better’ adapted. They pollinate more efficiently, or collect more nectar, faster.

But honey bees arrive in the environment mob handed.

Thousands of them.

Actually, tens or hundreds of thousands of them if there are several hives in an apiary. They are a formidable force and can easily outcompete other pollinators that are either solitary or only live in small colonies.

Save the bees, save humanity

When you see the phrase “Save the bees” what it usually means is save the honey bees.

Save the bees ...

Save the bees …

What it should be encouraging is “Save anything but the honey bees, because they don’t need saving … actually, there are possibly too many of them altogether”.

But that’s a lot less catchy … and it won’t let the supermarket, or food manufacturer or whatever, illustrate their campaign with cute photos of pollen-laden honey bees returning to quaint white-painted WBC hives in some sort of idyllic rural scene 4.

I suppose a photo of a honey bee would be better than drawing of a wasp though … which is what the NRDC used for a (mis)information campaign on CCD (colony collapse disorder) a few years ago.

D’oh!

Anyway … saving the bees is usually “greenwash” or bee-washing as it was termed by MacIvor and Packer in a 2015 paper on bee hotels 5

I’ll return to this topic, and urban beekeeping, later in the winter 6.

The Town mouse bees and the Country mouse bees

Where was I?

Oh yes, my – as will shortly be clear – incorrect assumption that country bees have access to more diverse and richer sources of forage than their poor relatives living in the town.

There are many sorts of countryside and many sorts of urban environments.

A hive in an intensively farmed arable landscape could be located in hundreds of acres of wheat fields, where all of the hedgerows were grubbed up years ago and replaced – if they weren’t just removed altogether – with barbed wire 7

How different is that environment to the ‘concrete jungle’ of a modern city? 

Tokyo

Surely that must be a terrible environment for bees?

In contrast, the suburban sprawl that surrounds most cities is possibly a good place for bees to live. Lots of neat little gardens, each 8 with a profusion of flowering plants, each chosen to provide vibrant colour for a much longer period than native plants.

And I’m sure we can all think of forage-rich rural environments. Here the bees gorge on early crocus, then gorse, willow, oil seed rape, clover, lime, blackberry, fireweed and himalayan balsam, before finishing the season will full crops and corbiculae from the ivy.

Now, in a recent publication 9 scientists have compared the forage available to town and country bees, and the results are quite surprising.

Let the bees tell you

If you live in a country with enlightened right to roam laws (like Scotland) you could wander around the countryside recording all the forage available to bees.

But the laws in England are much less enlightened. However, your right to roam in either country does not extend to the land around a private house or building. 

So, although you might be able to determine the forage available in the Scottish countryside, you can’t be certain you would have good enough access to do the same in England. And in a city you could only map what forage was available by peering over fences from public roads. 

So Elli Leadbetter and colleagues let the bees do the work.

They established 20 observation hives. Ten were in the the centre of London and 10 in agricultural land to the North East and South West of London. The hives were 5 km from each other to avoid overlapping areas of forage. They used observation hives so that they could watch and record the waggle dances of foragers in the hives.

I’ve discussed the waggle dance before. It is used to communicate three important pieces of information about a forage source:

  • direction
  • distance
  • quality

The first two bits of information are encoded in the angle of the waggle run to the perpendicular and the duration of the waggle run. The quality is conveyed by the number of circuits a dancing working performs. It’s a case of ‘the more, the better’ … energetically higher quality resources 10 result in more circuits.

Having recorded thousands of these waggle dances, they used the direction and distance information to ‘map’ where the bees were foraging.

GIS data, land use and foraging bees

For many locations there exists a wealth of land use data (GIS data; Geographic Information Systems). Much of this is at high resolution. For each of the 20 observation hives they produced a map of land use within 2.5 km of the hive at a resolution of 25 m. 

Land use was defined in broad categories such as 11 buildings, woodland, arable, pasture, fruit, OSR (all in agricultural areas) and dense or sparse residential, parks, amenity grassland or railways (all in urban landscapes). 

They then used some clever mathematics to decode the waggle dances 12 to work out where the bees had been, converting the distance and direction components to geographic locations.

Urban (top) and rural foraging heat maps, overlaid on GIS land use maps (5 km diameter)

These locations were overlaid on the land use maps to produce ‘heat maps’ showing where the bees were foraging. The image above shows these heat maps. In the spring the urban bees (top left) were foraging intensively to the east and west of the hive and the rural bees (bottom left) were mainly foraging in two large areas to the south east and south west of the hive.

Foraging distance and nectar quality

Even a cursory look at the image above shows that the urban bees tended to forage closer to the hive than the rural bees. But remember, that’s just three snapshots during the season.

Waggle run duration – rural bees fly further

However, more detailed analysis confirmed that this was the case. Throughout the season, the bees in the agricultural landscape foraged further from the hive. I’m showing the log-transformed median waggle run duration (above) as this allows slightly easier comparison across the season. The further the wiggly ‘best fit’ line is above the horizontal axis, the longer the duration of the waggle dance run, and so the further the bees are flying to find the forage.

Interestingly, the median foraging distances were relatively short when compared with the maximum foraging distances from the decoded waggle dances. This applied wherever the bees lived. For urban bees the median was 492 m (max 9375 m) and for agricultural bees it was 743 m (max 8158 m 13 ).

Perhaps the agricultural bees were flying further because there was better quality nectar available at more distant sites?

Nectar concentration (% w/w) sampled from returning workers

They controlled for this by recovering returning foragers and robbing them of their nectar load before analysing the sugar content. There was no significant difference 14 between the nectar from agricultural or urban landscapes. The sugar content of the nectar was recorded as reducing through the season.

Foraging preferences

So where did the town bees and the country bees prefer to forage?

City rooftop bees

City rooftop bees …

In urban areas the bees exhibited a strong preference for residential gardens (the ‘sparse residential land’) … these are presumably the flower-rich urban gardens that the homeowners also tend to prefer.

In contrast, bees in an agricultural landscape showed an entirely unsurprising reliance upon mass-flowering crops like oil seed rape (in spring only). They also showed weaker preferences for arable land and fruit crops throughout the season.

Mid-April in the apiary ...

Mid-April in a Warwickshire apiary …

I’ve skipped over a host of additional observations from the study, and almost all of the controls. Two things that are worth mentioning though.

Firstly, hive strength had no influence on waggle dance duration (and hence foraging distance). It therefore wasn’t the case that stronger hives had a larger workforce that could survey and exploit more distant forage. 

Secondly, cities are warmer due to the urban heat island effect. However, temperature also did not affect waggle dance duration when it was factored in. So, the city bees aren’t foraging at shorter distances because the dance is truncated at higher temperatures.

Conclusions

So, although cities are predominantly filled with buildings and roads, city bees travel less far to forage when compared to bees in agricultural landscapes.

This strongly suggests that the urban landscape consistently provided more available forage 15

Conversely, the bees in agricultural landscapes had to fly further, not because there were better quality nectar sources available at long-range, but because there wasn’t enough nectar nearby.

There were a number of additional interesting points in the paper, some of which were known already from other studies. For example, the high sugar content in spring nectar was already known (and confirmed here). Similarly, foraging distances in midsummer were longer than those in spring or autumn. This could be predicted due to the reduced rainfall in summer, and consequently the reduced overall level of nectar available.

I need to think more about how this study contributes – if at all – to the ‘too many bees in cities’ argument. If anything, forage-rich towns should be able to support a greater number of bees 16 without the honey bees impacting on other species. In contrast, honey bees in agricultural landscapes might dominate the available nectar sources because they can forage at long distances and then communicate to their nestmates the location.

Perhaps it just shows that that heavily farmed land is actually very poor in terms of nectar availability? It’s either boom or bust … once the OSR has finished, or the clover has been ploughed in, or the fruit trees stop flowering then there’s nothing left 🙁

It would be interesting to conduct a similar study in a forage-rich, non-agricultural, rural landscape.

Access all areas

Finally, I think a particularly neat thing about this study is the use of bees to ‘map’ the forage availability using what the authors term “a large-scale search effort that has no access limitations”. The scientists interpreted the waggle dance to get information that would otherwise have been difficult or impossible to determine.

However, using the bee’s own perception of the distances flown might actually lead to inaccuracies in the calculations. As discussed previously, bees measure distance by optic flow. Optic flow increases in complex landscapes … and cities are likely (at least to us, and certainly when compared with arable farmland, to bees) to be complex landscapes. Increased optic flow leads to a perception of increased distance, and hence to longer waggle runs.

This means that bees in complex landscapes might overestimate the distance they have actually flown to forage. Conversely, those in uniform landscapes might underestimate.

Which means that the results of this study may be a conservative estimate of the differences in foraging distance.

And therefore a conservative estimate of the differences in forage availability in urban and agricultural landscapes.


Notes

Dancing in the City was a pretty cheesy song that reached #3 in the charts for the rock-pop duo Marshall Hain in 1978. Having remembered the track when thinking up a title for this post, I made the mistake of listening to it on Spotify.

I now can’t get the damned thing out of my head. 

But it gets worse. I rummaged through Wikipedia and discovered that Kit Hain, the vocalist, subsequently had a very successful songwriting career with people like Roger Daltrey, Chaka Khan and Fleetwood Mac. Impressive. 

In contrast, Julian Marshall, the keyboard player became a member of the Flying Lizards who had a minor hit with a cover version of Barrett Strong’s 17 Money (That’s What I Want)

… and now I can’t get that out of my head 🙁

Counting by numbers

Can bees count?

If they can count, what’s the highest number they can count to?

Do they understand the concept of ‘more than’ or ‘less than’? And what about zero? These are very much more complex concepts than simple numbers.

If bees have simple counting skills, can they do mathematics? Addition, subtraction, multiplication and division?

What about more complicated maths like differential equations or Fourier transforms? 1

And finally, if we can determine the answer to all these questions, do we know how bees count? Do they simply see things and think “Ah Ha! Two flowers each with four petals”, or do they count in a non-numerical way?

Numbers, arithmetic, more than, less than, zero etc. are complicated concepts that involve aspects of neuroscience, psychology and even philosophy. I’m a molecular biologist/virologist and so singularly ill-equipped to understand the more esoteric or advanced aspects of these topics.

Don’t say I didn’t warn you 😉

Can bees count?

Yes.

Bees, like many other animals have basic counting skills.

In studies going back 25 years, Lars Chittka 2 demonstrated that bees exhibited what he called protocounting. He positioned a feeder between distinctive landmarks (tents in a field) and showed – by altering the number of tents between the hive and the feeder – that the ability of the bees to find the feeder was at least partly due to their ability to count the landmarks.

Counting by bees

If he added more tents between the feeder 3 and the hive, the bees flew a shorter distance to where they thought the food supply was. If he removed some of the landmarks, the bees flew further.

Chittka used the term protocounting because he reasoned that the things that the bees were counting – in this case tents in a row in a field – may not be transferrable to different objects. For example, bees trained to a feeder between tents 3 and 4 in a series might not return to the same position in a series of trees in a row. He didn’t test this, but others now have.

Bees also measure distance flown and this had a greater influence on where the bees searched in the series of landmarks. Nevertheless, these early studies provided compelling evidence that bees had some basic counting skills … or numerosity as it is called.

Is this ‘just’ protocounting and how high can they count?

To understand numerosity in more detail scientists moved the experiments into a laboratory setting where they could control the environment much more tightly.

Landmark counting in a laboratory flight tunnel

These use uniform flight tunnels containing painted or taped on landmarks. For some of the detail read the legend in the figure above 4. By using flight tunnels they could change the landmarks – see (a) above – from stripes to dots to baffles. In doing so they demonstrated that the bees were counting landmarks per se, rather than a particular type of landmark.

For example, bees trained to search for food between the third and fourth set of stripes would look between the third and fourth set of dots. This is much more advanced than the protocounting proposed in the initial study by Chittka and colleagues. … it shows a degree of abstract numerosity.

The use of baffles prevented the bees ‘looking ahead’ (or behind) to visualise the entire set of landmarks together … they had to keep a running total in their heads.

Finally, the highly controlled environment of a flight tunnel enabled the researchers to determine that bees could count up to … wait for it … four.

Not a huge number but, in terms of cognition, a significant advance on none, one or more.

But let’s not get ahead of ourselves.

We’re going to tackle the concept of zero and ‘more than’ in a minute.

It has been argued that the upper limit of four – a limit shared with a number of other animals – might be a consequence of the small size of the bee’s brain 5 and the small percentage of the neurones in the brain being dedicated to counting 6.

However, it may represent a more fundamental limit of cognition and perception that reflects the capacity limit of working memory. This isn’t restricted to bees … it’s something shared with beekeepers. For more detail on this I recommend Nelson Cowan’s The magical number 4 in short-term memory: A reconsideration of mental storage capacity. 7

Go on … knock yourself out 😉

More or less … and zero is not a number

Actually, it is.

What’s more, it’s an even number … 0, 2, 4, 6, 8 are the first five even numbers from zero.

It’s the ’empty set’, smaller than one.

It’s also, conceptually, a difficult number to grasp. Children take much longer to understand that zero is a number (e.g. that they can do maths with) than they do to understand that zero means “nothing”.

There are four steps defined in the acquisition of the understanding of zero in human history, psychology, animal cognition and neurophysiology” 8, which are:

  1. defining zero as ‘nothing’
  2. the categorical definition of zero as ‘nothing’ versus ‘something’
  3. an appreciation that zero is a quantity at the low end of the positive integer numerical continuum (see above)
  4. the symbolic representation of zero i.e. 0, the Arabic number for use in maths

Can bees distinguish ‘more than’ or ‘less than’? And what about zero being ‘less than’ one?

The experiments to determine this were simple but elegant (as all the best experiments are 9) and involved training and rewarding bees to select targets that displayed more items or fewer items.

Bees trained to select ‘more than’ targets would choose one displaying four items over one with two or three. Similarly, the ‘less than’ trainees 10 would select two items rather than three or four.

More than, less than and zero

These experiments confirmed that bees ‘understood’ the concepts of more than or less than. The experiments were controlled to exclude the possibility that the bees were responding to other stimuli that changed in the target e.g. signal density or colour intensity.

And if that wasn’t enough 11 they also showed that the ‘less than’ trainees would choose an empty target when offered the choice between ‘some’ and ‘none’.

But there’s more … or less

The ‘popularity’ of the empty set – zero items – was directly related to the difference in the number of items displayed on the non-empty targets. For example, bees more frequently chose the zero option when numbers were numerically more distant (0 vs. 5 or 0 vs. 6) than those closer together (0 vs. 1 or 0 vs. 2).

This relationship between accuracy and numerical distance is called Weber’s law.

This demonstrates a significant degree of understanding of the place of zero in a numerical continuum, an extraordinary feat in a honey bee.

This appreciation of the concept of zero as a number is similar in ability to that shown by African grey parrots, non-human primates … and pre-school children.

That’s impressive.

Counting by numbers

These numerical skills, amazing as they are 12 demonstrate an appreciation of numbers, but not the ability to manipulate numbers.

Can bees count?

For example, could bees solve this testing little equation?

Uh oh ... swarming ...

Maxwell’s equation – the foundation of classical magnetism, optics and electric circuits … but you knew that already

OK, not so fast … is that really a fair test?

These coupled partial differential equations are quite challenging. As bees have yet to be trained to hold a piece of chalk, they can’t write QED 13 at the bottom of the blackboard to indicate they’ve solved it.

So what about these instead?

1 + 1 = 2

3 – 1 = 2

To test this Adrian Dyer 14 and colleagues substituted colours for mathematical operands during the training e.g. blue for addition, yellow for subtraction, coupled with shapes for the numbers.

Y shaped maze to determine if bees can do maths

They trained the bees using a classical reward-punishment system. This sounds worse than it is. It means they received delicious syrup 15 when they got the right answer, but bitter-tasting quinine when they got the wrong answer.

The more training the bees received, the better they got at maths – both addition and subtraction. Once trained, the bees were tested.

Honey bees can do basic maths

In this subsequent testing phase the bees got the correct answer about 75% of the time. If they had been choosing the answer at random they would have achieved only ~50% of correct answers.

So, if more than, less than and an appreciation of zero aren’t enough, bees can also do mathematics.

Though probably not partial differential equations 😉

How do bees count?

It’s not yet clear how bees actually count objects – like the shapes scientists train them to recognise in the Y shaped maze shown further up this post.

Numerical cognition is considered a higher cognitive activity. In humans we’ve abstracted the process and – for at least the last 1100 years – used Arabic numbers to indicate quantities of ‘stuff’.

Of course, humans could count long before this, as could the apes from which we are descended. But they don’t use Arabic numerals and nor do bees.

3 + 1 = 4

Humans can look at a diagram like the one above and immediately recognise and count the similar shapes – this is a process called subitizing and is restricted to small numbers of shapes. You can train computers to do the same thing using neural networks, object detection and counting the instances of the objects detected.

However this is both computationally expensive and exploits symbolic mathematics, neither of which are achievable in the tiny brain of a honey bee. They cannot inspect a complete field of view and conclude “four apples”, or “three black circles”.

Bees cannot subitize … their brains don’t work fast enough and their visual acuity, and compound eyes, are probably incompatible with the process.

Instead, recent modelling studies have suggested that bees might count objects by serial sequential processing.

If you observe honey bees traversing a Y shaped maze they closely inspect each and every element in the patterns they are presented with.

Simple neural model for counting in honey bees

Using just four neurones, this method appears to allow the bee to achieve the known capabilities of their numerosity i.e. counting to four, concepts of more than or less than, understanding zero, and the fulfilment of Weber’s Law.

This area of the science is even more outside my comfort zone than Maxwell’s equation (see above) and I recommend you read the article cited in the legend to the figure above for further details.

Unanswered questions

There’s clearly a lot more to understand about the numerical and mathematical abilities of honey bees. This will take time, but good progress has been made over the last decade or so.

A full understanding of the neuronal processing involved in object discrimination and counting will probably require an ability to determine which neurones are firing, and the pathways of neuronal communication.

Scientists are years away from being able to do this with honey bees. It necessitates the ability to introduce specific reporter genes (for example that turn green when a neurone fires) into individual cell lineages. We don’t have the tools to do this (yet), but it can be done with fruit flies (Drosophila) and some of the same methods do – or might – work in bees.

In the meantime it’s worth thinking about what the ability to count contributes to the biology and behaviour of bees.

Do plants with more petals have more nectaries, and do bees follow these numerical clues rather than – or in addition to – other visual or scent stimuli?

And why on earth do bees have the ability to do basic maths?

I can’t think of an advantage that this would confer to bees.

Can you?


Notes

The title of this post was going to be 0 … 1 … 2 … 3 … 4 … more’ but that would have looked terrible as a URL and would have sunk without trace in Google searches.

Instead I’ve used a play on the title of the 1988 Peter Greenaway film Drowning by Numbers. This has a fairy tale-like plot that involves three generations of women – all called Cissie Colpitts – drowning their husbands. Bernard Hill plays Madgett, the coroner encouraged to cover up the crimes and involves a series of invented games, one of which is called ‘Bees in the Trees’ (which seemed appropriate).

Drowning by Numbers … going by the number in the background, a scene from about half way through the film

If you’ve not seen the film (and enjoy slightly surreal movies and black comedies) I can recommend it. See if you can count the numbers 1 to 100 that appear, almost all in sequence, either in the background or spoken by the characters. Michael Nyman wrote the music which is similarly highly structured, and based entirely upon a Mozart Sinfonia Concertante in E flat.

Of course Counting by numbers is also relevant as bees probably count in a different way altogether. Perhaps I should have ended the title of the post with a question mark?

Hydroxymethylfurfural

Excuse me?

Hydroxymethylfurfural which, for very obvious reasons is usually abbreviated to HMF, is an organic compound that forms in sugar-containing foods, often as a result of heating.

Hydroxymethylfurfural (HMF) Oxygen = red, Hydrogen = white, Carbon = black

HMF is relevant to bees because, at high levels, it is toxic for them. Since beekeepers often heat (or use ready-made feed that has been heated during production) sugar-containing syrups or fondants it’s worth being aware of it.

HMF is also relevant to beekeepers as high levels of it in honey are an indication of prolonged heating during storage and preparation or potential adulteration. For this reason there are legal limits on the levels of HMF in honey sold for human consumption.

I suspect beekeepers in the UK who know about HMF – and many may not – probably worry about it unduly. In tropical countries or regions where high fructose corn syrup is used as a bee food then HMF is likely to be of more immediate importance.

Natural occurrence of HMF

Hydroxymethylfurfural is essentially absent from fresh foods. However, in sugar-containing foods, particularly those that are acidic, HMF levels can build up. A chemical process called a Maillard reaction is responsible for HMF formation (there are other reactions that generate HMF as well, including caramelisation) and the reaction works about five times faster for every 10°C rise in temperature.

Therefore processes such as drying or cooking result in elevated HMF levels. The precise amount varies depending upon the foodstuff, the amount of heating and other factors; typical figures are bread 3 – 180 mg/kg, prunes 240 mg/kg, sugarcane syrup 100 – 300 mg/kg and roast coffee 900 mg/kg 1.

All of these foods can be consumed perfectly safely (at least in terms of their HMF content … prunes can have some adverse effects 😉  ).

It should therefore be obvious that the 40 mg/ml limit 2 of HMF in honey has nothing to do with its safety for human consumption.

Dietary HMF has been extensively studied as there were concerns it may be carcinogenic for humans. Several studies showed that non-physiological levels and/or prolonged exposure were cytotoxic or inhibited key enzymes in the cell such as DNA polymerase. However, no evidence for in vivo carcinogenic or genotoxic effects have been demonstrated 3.

HMF is currently considered safe and has been shown to have beneficial antioxidant activity, to protect against hypoxic (low oxygen) injury and to counteract the activities of some allergens.

HMF in honey

Readers familiar with the chemistry of honey will be aware that it is often rich in fructose (one of the sugars from which HMF is derived) and is acidic.

Add a little heat and you have near-perfect conditions for the production of HMF.

How much heat? 

It’s actually not just heat but a combination of heat and time.

The higher the temperature, the less time is required for the production of a certain amount of HMF. There are several studies of this, but one of the most frequently quoted is from White et al., in 1964 4 which has this slightly skewwhiff, but nevertheless useful, graph of the influence of storage temperature and time on HMF production in honey.

HMF production in honey – influence of storage temperature and time

That’s barely legible – check (and enlarge) the original if needed – but the approximate times/temperatures required to generate 30 mg/kg of HMF in honey 5 are as follows:

30°C ~250 days
50°C ~10 days
70°C ~10 hours

All of which is good news … heating a 15 kg bucket of rock-solid OSR honey overnight at 50°C to melt it before making soft-set honey is unlikely to significantly increase the HMF levels.

How to avoid the generation of HMF in honey

But, if you are worried about HMF levels, you could always produce creamed honey which just requires overnight warming at 33°C.

This is what I now do; not because of any concern over the HMF levels but because it’s:

  • faster
  • produces a honey with better batch-to-batch consistency of texture
  • generates a jarred honey much less susceptible to frosting

Long-term storage of honey results in the formation of HMF. The lower the temperature it is stored (and the shorter the time) the less HMF is produced. For an exhaustive list of HMF levels quantified in honey stored at different temperatures have a look at Table 1 in Shapla et al., (2018).

Store honey carefully in a cool place … or sell, eat or gift it quickly

It makes senses to store honey in a cool place with a relatively stable temperature.

Quantifying HMF

There are a variety of ways of detecting HMF. Unfortunately, all require laboratory equipment and none are really suitable for home use.

There are spectrophotometric methods – essentially detecting a colour change after adding an indicator that reacts to the presence of HMF – but these can lack both sensitivity and specificity. Some of the chemicals involved are carcinogenic.

More accurate and sensitive are methods use reversed-phase high-performance liquid chromatography. These have been in routine use for years.

Orbitrap ID-X Tribrid Mass Spectrometer

Probably the newest and most advanced methods involve the use of time-of-flight mass spectrometry (MS MALDI-TOF). These ionise the constituents of the sample and measure the time they take to reach a detector. Mass spectrometry is exquisitely sensitive and specific … and the equipment is eye-wateringly expensive. 

Since you’re unlikely to have one in your honey processing room 6 you’re better off doing your best to avoid conditions that lead to the build-up of HMF in the first place.

OK, enough about honey and humans, what about the bees?

HMF is toxic for both adult bees and developing larvae. The level of toxicity depends upon the concentration of the HMF, the duration of exposure and the developmental stage of the bee.

Krainer and colleagues 7 looked at toxicity of HMF to developing larvae and showed that concentrations up to 750 ppm (i.e. 750 mg/kg) did not reduce larval or pupal mortality.

Larval and pupal mortality when exposed to HMF at different concentrations.

They calculated that the LC50 (concentration that produced 50% mortality) at day 7 and day 22 was 4280 ppm and 2424 ppm respectively, with a calculated LD50 (dose per larva that resulted in 50% mortality) of 778 μg and 441 μg at day 7 and day 22 respectively.

Adult bees were less sensitive to HMF in the first week after emergence than during the first week of larval development.

Adult bee mortality when fed a diet containing HMF at the levels specified

What does all this mean?

It means that high levels of HMF are likely to have a significant impact on adult bees, but – at least until the levels are exceptionally high (grams, not milligrams, per kilogram) will probably not adversely impact brood levels.

Further validation of the adverse effects of HMF to adult bees

A similar study was recently conducted by Gregorc and colleagues 8 using lower concentrations of HMF.

Survival of adult bees fed with HMF-spike Apifonda

Again, there was a time/dose response, but note that only about 30% of the control bees survived 30 days and this was only double the number that had been fed the lowest level of HMF-spiked Apifonda. Note the clear evidence of a dose-response with increasing levels of HMF in the diet.

Dysentery

Several studies, dating back at least 50 years, report that high levels of HMF result in dysentery-like symptoms due to ulceration of the gastrointestinal tract of honey bees.

Gregorc and colleagues used immunohistochemistry to investigate the integrity of the gut tissues in the honey bees fed HMF. They stained cells red that were undergoing a process called ‘programmed cell death’ or apoptosis. This is a natural physiological response to damage. The more red staining, the worse the damage.

Midgut of formalin-fixed, paraffin-embedded tissue of worker bees exposed to HMF

At higher doses of HMF and/or longer exposure there was increased apoptosis in the gut tissues, presumably accounting for the dysentery-like symptoms often seen (though these were not recorded in this particular study).

Real world beekeeping

All of these bee corpses and fancy-dan immunohistothingamajiggery really just confirm that high levels of HMF are a bad thing™

In terms of honey processing and storage the allowed levels are nothing to do with human (or bee) health, but everything to do with evidencing overheated, poorly stored or doctored honey.

And since no readers of this blog do these things then there’s no need to be concerned 😉

Assuming your honey starts with low HMF levels (on extraction) then any reasonable levels of heating to liquify honey for filtering, blending or jarring should not result in HMF levels anywhere near to those that would prevent the honey being saleable 9.

Refer to the graph above from the 55 year old paper from White and Co. (shown above) for further validation.

If you’re making thick (2:1 by weight sugar to water) syrup to feed bees perhaps use warm rather than boiling water. However, considering the time involved and the absence of the acidity of honey, even with the latter HMF levels should not get close to high enough levels to endanger the bees.

If you’re making thin (1:1 by weight) syrup then use cold water. Just stir it a bit longer to dissolve it all.

However, take care – or avoid altogether – the use of high fructose corn syrups (HFCS) for feeding bees. I don’t know anyone who does this in the UK and have no experience of it myself. To learn more have a look at this article in Bee Culture. HFCS is high in fructose (the clue is in the name) and acidic, so HMF readily forms.

Studies of commercial HFCS show levels of HMF can start at 30 – 100 mg/kg before any long-term storage. 

Oxalic acid

The only time most beekeepers probably need to have concern about HMF levels is in the preparation and storage of oxalic acid solutions for trickle treating colonies in midwinter.

Oxalic acid is, er, acidic. For trickle treating it’s mixed with thin syrup to make a 3.2% solution. The combination of syrup and acidity means that HMF can be produced if stored – for a long time – in unsuitable conditions (under which there is an obvious colour change).

Stored OA solution and colour change

Stored OA solution and colour change …

So, if you’re preparing OA solutions for trickle treating either:

  • use it immediately and safely dispose of the excess
  • store it at 4°C and use then it as soon as possible (before safely disposing the excess)

Fondant

But what about fondant?

The HMF levels in commercially available fondant have recently been discussed on the Beekeeping Forum. I’m grateful to ‘loyal listener reader’ (to use Radio 4’s More or Less definition) Archie McLellan for bringing this to my attention.

The thread started with the challenging title The truth behind fondants.

Like all discussion groups, the contributions are many and varied.

Some wander off-topic.

Others use it as an opportunity to get a little dig in at the opposition.

Or a great big dig 😉

Novices and the naive ask simple questions and hope for straightforward answers 10.

Usernames often give no indication of who the poster actually is.

Is the poster a manufacturer or distributor of BeeCentric fondant™ “The best fondant for bees and a whole lot better than that cr*p they sell for ice buns”

Does the poster use 5 tonnes of fondant a year and buys anything s/he can get as long as it’s cheap enough?

Or does the contributor have a £576,000 Orbitrap MALDI-TOF mass spectrometer in their basement and a damned good idea of exactly how much HMF is present in every commercial source of fondant?

On the internet, nobody knows you’re a dog

Who knows?

I certainly don’t know all of the contributors to these threads.

But I know some of them 😉

Read the thread. It’s now 12 pages long and you’ll do well not to get lost or to disappear down a few cul-de-sacs

If you’ve ‘got a life’ and want to cut to the chase then have a look at this post in particular.

What do I do?

I use standard Baker’s fondant. It costs about £8-12 for 12.5 kg depending how much you need. I’ve used this type of fondant for a decade for 90% of my colony feeding (and 100% of my autumn feeding).

I’ve never seen any adverse effects from using this type of fondant for my bees.

I simply do not believe some of the negative marketing that is used to promote BeeCentric fondant™ costing £36 for 12.5 kg. It’s not that I can’t afford this 11 and it’s certainly not because I don’t care about my bees. I simply choose to trust experience over carefully-worded marketing ‘information’.

To convince me they’d need to publish the HMF levels in their products. They might be lower than bog-standard Baker’s fondant.

And I’d also want to know the HMF levels in standard Baker’s fondant 12.

If they were significantly higher 13, are they anywhere near high enough to damage my bees?


Note

A version of this article appeared in the November 2021 edition of An Beachaire – The Irish Beekeeper.

Winding down

Here in Scotland the season is rapidly drawing to a close. All of the summer nectar sources – the lime, blackberry and heather – have stopped yielding and the bees are noticeably less busy, other than in the warmest parts of the day.

Inside the hive the colony is segueing from summer to winter bee production. Brood rearing is still ongoing and there’s lots of pollen still going in, but the rate at which the queen is laying is very much reduced.

And, as the bees transition from summer to autumn behaviour, my own beekeeping activities are also changing. No more queen rearing, uniting or even colony inspections. The risk of swarming ended months ago.

Instead, with the winter ahead, the number of evening talks is increasing and several winter beekeeping projects are starting to occupy my mind.

But the season’s not over yet and there are still a few last minute tasks before active beekeeping stops. Here is what has been keeping me busy over the last week or two …

Talk, talk

Beekeepers are a sociable bunch and the pandemic has had a significant impact on the amount of digestive biscuits consumed and tea slurped in church halls across the country.

However, in addition to being sociable 1 they are also adaptable and inventive. Zoom and GoToMeeting talks, attended from the comfort of the sofa with a glass of red wine, have become the new normal. 

Early forays into the world of ‘virtual’ beekeeping were plagued with dodgy connections or noisy feedback.

Q&A sessions were stilted due to the lack of familiarity with the need to unmute the microphone before talking.

Some were more like a Marcel Marceau tribute act than Beekeeper’s Question Time.

But all that has changed.

I’ve experienced some excellent hosting, lively and interactive Q&A sessions and entertaining pre- or post-talk chat with beekeepers across the country. 

‘Virtual’ beekeeping talks

Increasingly this format appears to have been widely accepted. There may not be face-to-face meetings with tea and biscuits, but there’s also no need to drive half way across the county on a filthy, wet winter night.

Long distance talks – imagine the travel expenses being saved

I live in one of the most westerly locations in the UK (I’m about 15 km west of Land’s End) and have used the title ‘Go West young man’ a couple of times in previous posts. Later this winter I’ll be ‘virtually’ going west a further 7000 km and talking to beekeepers in British Columbia, Canada. They may be half way across the world, but their climate (reasonably mild and wet) is not dissimilar to the west of Scotland, and bees are bees 🙂 

It should be interesting.

Zoom and GoToMeeting

About 95% of the talks I give (or attend) use Zoom. It works well. The interface is logical and I can see some/all of the audience. Questions are often handled through the ‘Chat’ function. At least a couple of associations have invested in an add-on 2 that allows questions to be upvoted, so moving the most popular or relevant topic 3 to the top of the pile. 

‘Seeing’ the audience in the talk isn’t really necessary, and can be a bit distracting 4. But I find it really helps during the Q&A session, and certainly makes the ‘virtual’ interaction just that little bit more realistic. 

At the very least I can guesstimate the age and experience of the beekeeper asking the question, so allowing me to tailor my answer if appropriate. Of course, this sometimes goes wrong, but people are usually too polite to point out my error.

GoToMeeting is less intuitive (possibly because I’ve used it less) and I don’t think offers me a view of the audience 5. However, I think it’s more suited to larger audiences and coped admirably with ~250 who attended a recent talk to the Welsh BKA.

OK, enough virtual beekeeping … what about the real thing?

Heather honey

In the six years I lived in Fife (on the east coast of Scotland) I never moved my bees outside a 20 mile corridor in the centre of the county. The arable farmland, mixed woodland and low, rough grazing contained no (worthwhile) heather.

Therefore, despite living in Scotland, I’ve no previous experience with heather, considered by many to be the ultimate honey. However, on the west coast we have patchy heather on the hill behind the house, so the bees have almost no choice but to forage there.

After a record-breaking honey yield in Fife, anything extra in the west was a bonus.

I was singularly ill-equipped to extract it. A few of the frames I put through the extractor collapsed spectacularly, so I was reduced to scraping the frames back to the midrib and crushing and straining the honey out.

As I’ve said before, there’s always something new to learn.

Crushed and strained … I was, but I got there eventually

And I learnt that this can be a messy and exhausting process 🙁

One of many few … my first jars of Ardnamurchan honey

But, by golly, it was worthwhile 🙂

I now have to buy a larger shed to store a compressed air-driven fruit press as extracting anything more than half a dozen supers of heather honey will probably drive me round the bend.

Based on the price of these fruit presses and the likely honey yield per year I reckon I’ll break even in about 29 years 🙁  6

The heather here on the west coast goes on yielding long after the bees in Fife have packed up and gone home.

At least, usually. 

Feeding and forage

The summer honey came off the hives in Fife in mid-August. All the colonies were treated with Apivar strips and received a full block of fondant on the same couple of days I removed the supers.

It was hard work, not least because there was a lot of honey. All the supers were brought back home for extracting, and subsequently returned for storage.

As described a couple of weeks ago, I only feed fondant in the autumn. Having checked the colony is queenright I simply plonk a block of fondant on the hive and leave them to get on with it 7.

When I checked the colonies earlier this week all had completely finished their 12.5 kg fondant block.

All gone

Although I didn’t do a full colony inspection, I did have a peek in a couple of hives to check the level of stores and brood. They were wall-to-wall with capped stores except for 2-3 frames in the centre of the brood box which contained about a hands-breadth of brood. Much of this brood was capped and there was still a little bit of space for the queen to lay … but not much.

However, several boxes also had brace comb in the super above the empty bag of fondant. None of this contained brood as I always support the block of fondant on a queen excluder. 

Bees don’t draw comb on fondant … or do they?

I suspect this comb building was triggered by the availability of ivy nectar. In previous years I’ve not seen comb drawn when feeding fondant. However, it’s been quite mild and the bees have probably been taking advantage of the warm weather to supplement the fondant.

Avoiding another sticky mess

I don’t want to leave the bees with a third of a super of ivy honey, particularly when the rest of the super is a big empty space they would have to heat. However, I also don’t want to mess about cutting it all away or – worse – wasting all their efforts.

A small hole

Therefore, having removed the queen excluder and the empty fondant wrapper I placed a new crownboard and empty super back on the hives with brace comb. I modified the crownboard to reduce the hole to about a single bee width.

Regular readers will know that modified almost always means either gaffer tape or Correx.

I’ve branched out this time and instead used the side of a cardboard box of fondant for one hive. If this works I’ll claim it was a well thought out experiment. If it doesn’t I’ll claim I was pushed for time and had no Correx or gaffer tape with me 8.

Having done all this I added back the original crownboard with the attached brace comb and closed the hive up securely.

The intention here was to make the stores in the brace comb appear as though it was outside the hive. I expect the bees to relocate the nectar from the brace comb – none of it was capped yet – to the brood box, as and when space become available.

No top ventilation please

Finally, reinforcing the point I made recently about the dislike bees have for top ventilation, every single Abelo crownboard “vent” was gummed up solidly with propolis. 

I’ve got the message loud and clear. No matchsticks needed here.

Scratch and sniff reposition

Apivar strips need to be placed in the edges of the brood nest, at least two frames apart and in diametrically opposing corners of the hive.

But in mid-August the brood nest is a lot larger than it is a month later. As the brood nest shrinks, the strips get further and further away from the main concentration of the bees in the hive.

In an active hive stuffed with bees this probably isn’t a major issue. However, to achieve maximum exposure of the bees – particularly the young bees that Varroa like to hang out with and that are concentrated around the brood nest – it makes sense to reposition the strips midway through the treatment period.

Apivar strip placement as the brood nest shrinks

Apivar treatment takes 6-10 weeks. The actual wording is something like “The larger the brood is, the longer the strips should be left in the limit of 10 weeks”. I usually treat for 9-10 weeks; my colonies are all pretty strong at the end of the summer.

But strips left for that long in the hive often get gummed up with propolis and wax.

Apivar strip efficacy is probably impaired by all that propolis and wax

I therefore spend a few minutes scraping the strips clean of gunk 9 and then reposition them in the hive, adjacent to the – now shrunken – brood nest.

There are studies showing that this scratching and repositioning of the Apivar strips marginally increases the devastation wreaked on the mite population.

Apivar scratch and sniff repositioning studies

And that can only be a good thing™.

More heavy lifting

I returned to the west coast after two long days of driving, beekeeping and meetings 10 having collected a further 125 kg of fondant en route. 

The following day a pallet of jars were delivered from C Wynne Jones. I get the square jars I like – and, more importantly, my customers like – from there. Because of my remote location the ‘free delivery’ comes with a hefty surcharge, so it makes sense to buy a reasonable number at once.

Unfortunately the courier transported them on a 36 ton artic, and there was slightly less than no chance whatsoever that it would be able to negotiate our ~300 metre, 1 in 5 driveway.

I’d had a barely decipherable call (wrong mobile network) from the driver in the morning as he arrived on the peninsula but heard nothing more. I presumed he was still negotiating the ~18 miles of single track road to get here.

Either that or he’d got no phone reception.

I was right on both counts.

He knocked at the door having been unable to call me, but had abandoned the lorry in the road and walked up the hill to the house. 

What a star.

With thanks to Palletline

In exchange for a jar of honey – to restore his flagging blood sugar levels – he unloaded the pallet in the road and I made four trips by car to collect the boxes.

Beekeeping is a high-volume pastime 11 … everything takes up a lot of space.

I think I need to find another location for the canoe that occupies one side of the shed.

In between all the heavy lifting …

And canoeing with the dolphins in the loch is the other thing I’ve been enjoying now the majority of the beekeeping is winding down for the year.


 

Beekeeping fantasy vs. reality

There have been a couple of stories in the press recently that have made me think about the idealised version of beekeeping that is often promoted … with the reality of a lot of amateur beekeeping 1.

Most recently was the announcement of the new CBBC show titled Show Me the Honey! which will be available at the end of this month on iPlayer.

Information is a bit limited at the moment. It’s clearly a programme featuring and for children. According the The Guardian it “features five children and their families taking part in a series of weekly challenges to create the best hive and tastiest honey, with the winner taking home the beekeeper of the year trophy”.

Undoubtedly this will increase interest in beekeeping. This isn’t in itself a bad thing, though the timing is a bit off. The seven week series will end with much of the winter left to run.

Not the best time to start beekeeping

Will those watching who are captivated by the thought of keeping bees go for the ‘quick fix’ of an expensive mid-March nuc thinking “What can be so difficult? One of those kids became the ‘Beekeeper of the Year’ in just seven weeks”.

Or, will they do their homework, attend a Start beekeeping course with a local association, go to a couple of ‘bee handling’ sessions in the association apiary, find a mentor … and only then order a locally sourced nuc?

I’m pretty sure I know which route is more likely to produce a future ‘beekeeper of the year’ 😉

Competitive beekeeping

Just like Show Me the Honey!, my beekeeping often involves a set of ‘weekly challenges’.

  • Where is my bloody hive tool?
  • Your mission, should you choose to accept it, is “To find, mark and clip the queen in this double brood monster of a hive, bulging with psychopathic bees … before the rain starts”.
  • Can I lift these three full supers together without causing permanent damage? 

The concept of competitive beekeeping grated a bit when I first read about it, but the reality is that beekeeping can be competitive.

Think about the annual honey shows.

A bit of lighthearted entertainment for the end of the season?

Or a cutthroat affair, with lashings of deviousness and skulduggery to produce the best 1 oz wax blocks?

That sort of competition I can cope with, although I no longer partake as I’m a very bad loser.

And I lost … a lot 🙁

But think about what’s happened to climbing, and the huge success it was at the Olympics. The speed climbing event is probably now the fastest non-gravity-assisted 2 Olympic sport. 

Perhaps the inevitable adult or celebrity spin-offs of Show Me the Honey! will involve speed inspections?

3 … 2 … 1 … GO!

With Martha Kearney doing the commentary … 3

The best hive

So let’s return to that quote from The Guardian … ‘the best hive’.

Are they going to start with a Thorne’s Bees on a Budget flatpack cedar hive, a mismatched pile of nails, a hammer and a set of IKEA-ish hieroglyphic 4 instructions?

Is the winner the one who gets everything square and true? Does beespace matter? What about injuries? 5

Or perhaps it will be to dream up ‘the best’ new hive design … and there’s lots of competition for that.

How about the urban-friendly 6 B-Box the first ever beehive designed for home beekeeping’.

The B-BOX

Hang on a sec … I’m currently at home.

Let me just check what’s in that blue and yellow box by the shed.

Don’t do this at home … this beehive is designed for other locations

Yep … just as I thought. Bees. It’s a beehive. 

Am I doing something wrong? Have I got a hive designed for beekeeping somewhere other than home? 

There are some grand claims made for the B-BOX and the website is awash with buzzwords 7. I’m not sure the 16 small honey ‘supers’ would be sufficient during a strong nectar flow from the lime trees found in many cities.

These hives are about €480 (plus an extra €580 or so if you want a ‘swarm’ of bees with it … and I think they probably do mean swarm from the description. Yikes!).

Or what about this Philips design – another Urban beehive – that “consists of two parts, a tinted glass shell that houses the honeycomb frames and a flower pot with an entry passage to the glass vessel. You can then harvest the honey produced, simply pull on the smoke actuator chain to calm the bees before it is opened”

Philips Urban beehive

Wow. 

I was sure that bees draw comb in a vertical plane? 

This one is a ‘concept’ hive, so is effectively priceless. 

Which would also be my reaction if I had to do a shook swarm on it 😉

Smart hives

I’m not sure that last hive is entirely practical. 

Instead, how about this ‘robotic’ hive – or Beehome as they call it – from Israeli startup Beewise? This is a container 8 housing 24 colonies which are constantly monitored.

The Beewise ‘Beehome’ robotic beehive

The technology is clearly pretty clever as they appear to be able (or claim) to:

  • provide climate and humidity control
  • monitor brood development on every frame of every hive
  • apply pest control (non-chemical, but it’s not clear what) to control Varroa
  • deliver swarm prevention by ‘changing the conditions in the hive’
  • automatically harvest honey … when the 100 gallon tank is full the Beehome calls you to come and collect

When you think of some of the manipulations needed for successful swarm control you wonder – well, I wonder – how on earth a robot could do it by simply ‘changing the conditions in the hive’

Their website shows a screenshot of an app displaying digital images of frames, together with schematics of the distribution of the various types of brood (capped/uncapped) and stores within the hive.

Very clever … though I do wonder whether the robot takes quite as much care as I do returning frames to the hive without crushing or rolling bees in the process.

What?

I thought you’d never ask … $400.

A month.

At least, that’s the price quoted on the website. I’ve no idea if that’s ‘all in’, or if there are hidden costs involved, like custom frames, software licenses. If it is ‘all in’ and every hive generates a good crop of honey each season it seems very reasonable.

But, and this is a biggy as far as I’m concerned, it seems to to rip the soul out of all that is special about keeping bees.

It’s more like factory farming.

Save the bees

But, inevitably, it ‘saves the bees’ … so that’s OK then 🙁  9

Hives in reality

So those are the fantasy hives that the public read about in the newspapers and that adorn press releases.

Super-clean and shiny and described in glowing terms as bee friendly, bee-centric, sustainable, healthier or a nature-based solution.

In many ways these are what shape their expectation and understanding of beekeeping.

The reality is that bees do just fine in almost any relatively secure container.

Like a hollow tree.

Or a dustbin.

Or a variety of beehive types …

Gaffer tape apiary

Gaffer tape apiary …

… including some that appear to consist mainly of gaffer tape.

Aesthetically perhaps less attractive, but perfectly functional.

I’ve discussed the concept of the ‘the best’ hive previously 10.

The 12-13 pages of different hive types in the Thorne’s catalogue describe a plethora of different sizes and designs. As long as they have the correct bee space and the boxes are broadly compatible – which really means flat interfaces – I’d be happy to keep bees in any of them.

Sure, some might suit my beekeeping a little better than others, but I reckon I’d do OK with them all. 

But, of course, I’d want more than one … which is where the compatibility becomes critical. I’d inevitably end up mixing ‘n’ matching different boxes during swarm control, autumn uniting or simply when running out of equipment.

Uniting with newspaper ...

Uniting with newspaper …

And it’s this reality that never appears in that glossy advertising on promotional websites. The ‘cobbling stuff together’ to make something that’ll do. In the picture above I’m uniting a queenless double hive with a queenright poly hive.

The poly hive is actually a bait hive built from two stacked supers. They are the Paradise/ModernBeekeeping design with an overhanging lip on the lower face, hence the thin, wide, wooden shim between the boxes.

And the crownboard is a piece of thick polythene.

All perfectly functional, but not quite as glossy, organised and coordinated as is often displayed in print or online 11.

But this neat, clean and pristine presentation doesn’t stop with the hives … 

Suits you Sir!

What about the protective clothing?

If you look at the photos above you’d think you could harvest honey (from the B-BOX) wearing a T-shirt and jeans, or inspect your Philips urban hive in a slinky Christian Dior LBD.

The reality is a little less flattering. 

Bees can sting, and agitated bees – with dodgy parentage or through sloppy handling 12 – can sting quite a lot. 

As a quick aside, I note that one of the presenters of Show Me the Honey! has apparently been ‘keeping bees for 15 years and has never been stung’.

And now back to reality 😉

Beesuits aren’t particularly flattering.

Does my bum look big in this? … doesn’t even come close. 

Everything … looks big in a beesuit.

And usually the beesuits are completely pristine, not stained with propolis, held together with gaffer tape or with pockets hanging off from hive tool damage 13.

Angelina Jolie and some slightly grubbier beekeepers

The beesuit Angelina Jolie is wearing is what they typically look like in ‘fantasy beekeeping world’. No broken zips, no propolis staining, no pockets bulging with emptied queen cages and old gloves.

Those worn by the beekeepers around her are probably a bit more normal, though I also have a sneaking suspicion they’ve worn their ‘Sunday best’ beesuits for the photo op.

As another aside, Angelia Jolie is promoting the UNESCO programme ‘Women for Bees’. This teaches beekeeping and entrepreneurship to women in UNESCO designated biosphere reserves around the world. Further details also in National Geographic.

And it doesn’t stop there

I’ve had a great beekeeping year.

There have been some notable successes – in queen rearing and mating, in preparing nucs and in a really excellent honey crop.

Show me the Honey!

However, it wasn’t all the clean, neat and tidy affair depicted in the press.

And, to be honest, parts of it could best be described as an omnishambles.

I’m being polite there.

Here are just a few examples where my beekeeping reality didn’t quite match the glossy, propolis-free, beautifully ordered and presented world of beekeeping fantasy.

  • Wrenching my back during the spring honey harvest by trying to carry too many supers. I walked hunched over for a month and spent quite a lot of time lying flat on my back.
  • Glenrothes – my base when beekeeping on the east coast. Underwhelming 14

Good morning Glenrothes

  • Installing a ‘lively’ nuc in a full hive before securing my veil. No stings, but a pretty close call with several bees agitatedly struggling to escape the space they’d seemingly so easily entered.
  • Lifting three supers off a hive in late July and carelessly 15 tripping over a hive roof. I dropped the lot and fell flat on my face. A very sticky mess but the bees were extraordinarily tolerant of my clumsiness.
  • Sweating so much during July inspections that my gloves filled with perspiration and my wrinkly fingers stopped ‘unlocking’ the phone.

Ewwww

  • Consequently dropping more queens in the grass than ever before. I was so cackhanded that it became unusual not to drop them on the ground before getting them into the marking cage.
  • Watching a much-needed virgin queen fly off out of sight while – stupidly – trying to get her into an introduction cage with the shed door open. D’oh!
  • Chasing another virgin queen around the shed – after closing the door 16 – for five minutes before getting her into a cage. 
  • Going half crazy trying to keep wasps out of cleared supers before stacking them in the car.
  • The hole in the hive pocket and no trousers debacle. Enough said 🙁
  • More lifting, more sweating, more wasps …
  • The long evening drive back to the west coast, tired, dehydrated and smelling of smoke and propolis 17.

Go west young man …

That’s the reality of a beekeeping season.

It’s been fantastic.

I wouldn’t have it any other way 🙂


 

Cut more losses

This is a follow-on to the post last week, this time focusing on feeding and a few ‘odds and sods’ that failed to make it into the first 3000 words on reducing overwintering colony losses.

Both posts should be read in conjunction with one (or more 1 ) of my earlier posts on disease management for winter. Primarily this involves hammering down the mite levels before the winter bees are produced, so ensuring their longevity.

But also don’t forget to treat your colonies during a broodless period in midwinter to mop up mites that survived the autumn treatment, or have reproduced since then.

Why feed colonies?

All colonies need sufficient stores to get the colony through the winter until suitable nectar sources and good enough weather make foraging profitable the following spring.

How much the colony needs depends upon the bees themselves – some strains are more frugal than others – and the duration of the winter. If there is no forage available, or the weather is too poor for the bees to fly, then they will be dependent upon stores in the hive.

A reasonable estimate would probably be somewhere around 20 kg of stores, but this isn’t a precise science.

It’s better for the colony to have too much than too little. 

If the colony has stores left over at winter’s end you can always remove them and use them when you make up nucs later in the season. Just pull out the frames and store them safely until needed.

Unused winter stores

In contrast, if the colony starts the winter with too few stores there are only two possible outcomes:

  • the colony will starve to death, usually in late winter/early spring (see below)
  • you will spend your winter having to regularly check the colony weight and opening the hive to add “emergency rations” to get them through the winter

Neither of these is desirable, though you should expect to have to check the colony periodically in winter anyway.

Feeding honey for the winter … and meaningless anecdotes

By the end of the summer the queen has reduced her laying rate and the bees should be backfilling brood comb with honey stores. If you assume there’s about 5 kg of stores 2 in the brood box then they’ll need about another 15 kg. 

15 kg is about the amount of honey you can extract from a well-filled super. 

Convenient 😉

Some beekeepers leave a full super of honey on the hive, claiming the “it’s better for the bees than syrup”

Of course, it’s a free world, but there are two things wrong with doing this:

  • where is the evidence that demonstrates that honey is better than sugar-based stores?
  • it’s an eye-wateringly expensive way to feed your colonies

By evidence, I mean statistically-valid studies that show improved overwintering on honey rather than sugar.

Not ‘my hive with a honey super was strong in spring but I heard that Fred lost his colony that was fed syrup’ 3.

That’s not evidence, that’s anecdote.

If you want to get this sort of evidence you’d need to start with a lot of hives, all headed by queens of a similar age and provenance, all with balanced numbers of brood frames/strength, all with similar mite levels and other pathogens.

For starters I’d suggest 200 hives; feed 50% with honey, 50% with sugar … and then repeat the study for the two following winters.

Then do the stats 4.

The economics of feeding honey

If I were a rich man …

The 300 supers of honey used for that experiment would contain honey valued at about £80,000.

That’s profit, not sale price (though it doesn’t include labour costs as I – and many amateur beekeepers – work for free).

The honey in a single full super has a value of £250-275 … that’s an expensive way to feed your bees 5.

Particularly when it’s not demonstrably better than a tenner or so of granulated sugar 🙁

But there are more costs to consider

The economic arguments made above are simplistic in the extreme. However, there are other costs to consider when feeding colonies.

  • time taken to prepare and store whatever you will be feeding them with 6
  • feeders needed to dispense the food (and storage of these when not in use)
  • energetic costs for the colony in converting the food to stores

Years ago I stopped worrying (or even thinking much) about any of this and settled on feeding colonies fondant in the autumn.

Fondant mountain ...

Fondant mountain …

Fondant is ~78% sugar, so a 12.5 kg block contains about 9.75 kg of sugar.

This year I’m paying £11.75 for fondant which equates to ~£1.20 / kg for the sugar it contains.

In contrast, granulated sugar is currently about £0.63 / kg at Tesco.

The benefits of fondant

Although my sugar costs are about double this is a relatively small price I’m (more than) prepared to accept when you take into account the additional benefits.

  • zero preparation time and no container costs. Fondant comes ready-wrapped and stores for years in the box it is purchased in
  • no need for jerry cans, plastic buckets or anything to prepare or store it in before use
  • no need for expensive Ashforth-type feeders that sit around for 95% of the year unused When I last checked an Ashforth feeder cost £66 😯 
  • it takes less than 2 minutes to add fondant to a colony
  • no risk of spillages – in the kitchen, the car or the apiary 7.
  • fondant is taken down more slowly than syrup, so providing more space for the queen to continue laying. In addition, in the event of an early cold snap, fondant remains accessible whereas bees often stop taking syrup down

Regarding the energetic costs for the colony in storing fondant rather than syrup … I assume this is the case based upon the similarity of the water content of fondant to capped stores (22% vs. 18%), whereas syrup contains much more water and so needs to be ripened before capping to avoid fermentation.

Fondant block under inverted perspex crownboard – insulation to be added on top.

Whether this is correct or not 8, the colony has no problem taking down the fondant over a 2-4 week period and storing it.

What are the disadvantages of using fondant? 

The only one I’m really aware of is that the colony will not draw fresh comb when feeding on fondant (or at least, not enthusiastically). In contrast, bees fed syrup in the autumn and provided with fresh foundation will draw lovely worker brood comb. 

Do not underestimate this benefit.

They fancied that fondant

Brood frames of drawn comb are a very valuable resource. Every time you make up a nuc, or shift a nuc to a full-sized box, providing drawn comb significantly speeds up the expansion of the resulting colony.

Nevertheless, for me, the advantages of fondant far outweigh the disadvantages …

Finally, in closing, I’ve not purchased or used invert syrup for feeding colonies. Other than no prep time this has the same drawbacks as syrup made from granulated sugar. Having learnt to use fondant a decade or so ago from Peter Edwards (Stratford BKA) I’ve never felt the need to look at other options.

Let’s move on …

Ventilation and insulation

Bees can withstand very cold temperatures if healthy and provided with sufficient stores. In northern Canada bees may experience only 120 frost-free days a year, and cope with 3-4 week periods in winter when the temperature is -25°C (and colder if you consider the wind chill).

That makes anywhere in the UK look positively balmy.

Margate vs. the Maldives … a similar temperature difference to Margate vs. Manitoba in the winter

I’ve overwintered colonies in cedar or poly boxes for a decade and not noticed a difference in survival rates. Like the honey vs. sugar argument above, if there is a difference it is probably minor. 

However, colony expansion in poly boxes in the spring is usually better in my experience, and they often fill the outer frames with brood well before cedar boxes in the same apiary get there.

Whether cedar or poly I take care with three aspects of their insulation/ventilation:

  • the colonies have open mesh floors and the Varroa tray is only in place when I’m actively monitoring mite drop
  • all have insulation above the crownboard in the form of a 50 mm thick block of Kingspan (or Recticel, or Celotex), either integrated into the crownboard itself, placed above it or built into the roof
  • I ensure there is no upper ventilation – no matchsticks under the crownboard, no holes etc.
  • excess empty space in the brood box is reduced to minimise the dead air space the bees might lose heat to

In my experience bees actively dislike ventilation in the crownboard. They fill mesh with propolis …

Exhibit A … are you getting the message?

… and block up the holes in those over-engineered Abelo crownboards …

Exhibit B … ventilated hole in an Abelo crownboard

Take notice of what the bees are telling you … 😉

Insulation over the colony

I’ve described my insulated perspex crownboards before. They work well and – when inverted – can just about accomodate a flattened 9, halved block of fondant.

Perspex crownboard with integrated insulation

Finally, if it’s a small colony in a brood box 10 then I reduce the dead space in the brood box using a fat dummy

Fat dummy with integral feeder

Fat dummy …

I build these filled with polystyrene chips.

You don’t need this sort of high-tech solution … some polystyrene wrapped tightly in a thick plastic bag and sealed up with gaffer tape works just as well.

Insulation ...

Insulation …

I’ve even used bubblewrap or that air-filled plastic packaging to fill the space around a top up block of fondant in a super ‘eke’ before now.

However, remember that a small weak colony in autumn is unlikely to overwinter as well as a strong colony. Why is it weak? Would you be better uniting it before winter starts?

Nucleus colonies

Everything written above applies equally well to nucleus colonies.

A strong, healthy nuc should overwinter well and be ready in the spring for sale or promoting to a full colony.

Here's one I prepared earlier

Here’s one I prepared earlier … an overcrowded overwintered nuc in April

Although I have overwintered nucs in cedar boxes I now almost exclusively use polystyrene. This is another economic decision … a well made cedar nuc costs about double the price of the best poly nucs

I feed my nucs fondant in preparation for the winter, typically by adding 1-2 kg blocks to the integral feeder.

Everynuc fondant topup

Everynuc fondant topup

Because of the absence of storage space in the nuc brood box it’s not unusual to have to supplement this several times during the autumn and winter.

You can even overwinter queens in mini-mating nucs like Apidea’s and Kieler’s.

Kieler mini-nuc with overwintering queen

This deserves a post of its own. Briefly, the mini-nuc needs to be very strong and usually double- or triple- height. I build fondant frame feeders for Kieler’s that can be quickly swapped in/out to compensate for the limited amounts of stores present in the brood box.

Kieler mini-nuc frame feeders

My greatest success in overwintering these was in winters when I provided additional shelter by placing the nucs in an unheated greenhouse. A tunnel provided access to the outside. However, I know several beekeepers who overwinter them without this sort of additional protection (and have done so myself).

Just because this can be done doesn’t mean it’s the best thing to do.

I’d always prefer to overwinter a colony as a 5 frame nuc. The survival rates are much better, their resilience to long periods of adverse weather is significantly greater, and they are generally much more useful in the spring.

Miscellaneous musings

Hive weight

A colony starting the winter with ample stores can still starve if the bees are particularly extravagant, or if they rear lots of brood but cannot forage.

The rate at which stores are used is slow late in the year and speeds up once brood rearing starts again in earnest early the following spring (though actually in late winter).

Colony weight in early spring

As should be obvious, this is a Craptastic™ sketch simply to illustrate a point 😉

The inflection point might be mid-December or even early February.

The important message is that, once brood rearing starts, consumption of stores increases. Keep checking the colony weight overwinter and supplement with fondant as needed.

I’m going to return to overwinter colony weights sometime this winter as I’m dabbling with a weather station and set of hive scales … watch this space.

An empty super cuts down draughts

Periodically it’s suggested that an empty super under the (open mesh) floor of the hive ‘cuts down draughts’, and is therefore beneficial for the colony.

It might be.

But like the ‘overwintering on honey’ (and being a pedant scientist) I’d always want to see the evidence.

There are two claims being made here:

  • a super under the floor cuts down draughts
  • fewer draughts benefits the colony which consequently overwinters better

Really?

There are ways to measure draughts but has anyone ever done so? Remember, the key point is that the airflow around the winter cluster would be reduced if there are fewer draughts. 

Does a super reduce this airflow significantly over and above that already caused by the sidewalls of the floor?

And, even if it does, perhaps the colony ‘reshapes’ itself to accommodate the draught from an open mesh floor.

What shape is the winter cluster?

For example, in an uninsulated hive (including no insulation over the cluster) with a solid floor the cluster is likely to be roughly spherical. They minimise the surface area.

With an open mesh floor are they more ellipsoid, so avoiding draughts from below? If so, is this improved much by an empty super below the open mesh floor? Does the cluster change shape or position? I don’t know as I’ve not compared cluster shapes in solid vs. open mesh floors plus/minus a super underneath.

And anyway, an open mesh floor looks very like a baffle to me … how much better can it get? How draughty is it in the first place?

Is this example 8,639 for my ‘Beekeeping Myths’ book?

I do know that top insulation tends to flatten the cluster against the warm underside of the crownboard.

Midwinter cluster

A strong colony in midwinter

Having worked out that draughts are (or are not) reduced … you still need another couple of hundred hives to test whether overwintering success rates are improved!

More winter bees

Finally, always remember that the survival of the colony is dependent upon the winter bees. All other things being equal (stores, disease etc.), a colony with lots of winter bees will overwinter better than one with fewer.

This is one of the reasons I stopped using Apiguard for mite control in autumn. Apiguard contains thymol and quite regularly (30-50% of the time in my experience) stopped the queen from laying, particularly in warmer weather. 

Apiguard works well for mite control, but I became wary that I was potentially stopping the queen at a time critical for late-season colony development. I worried that, once treatment was finished, a cold snap would shut down brood rearing leaving it with suboptimal numbers of winter bees.

I never checked to see whether the queen ‘made good’ any shortfall after removal of the treatment … instead I moved to Scotland where it’s too cold to use Apiguard effectively 🙁


 

Cut your losses

The stats for winter losses in the UK, Europe and USA can make for rather sobering reading.

In the UK, losses over the last 12 years have fluctuated between 9% and 34%. This self-selecting survey includes responses from about 10% of the British Beekeepers Association membership (primarily England and Wales, despite the name). The average number of hives maintained by a BBKA member is about 5, meaning – all other things being equal 1 – that most beekeepers should expect to lose about 1 hive every winter.

BBKA winter losses survey

About 30 countries, mainly Northern hemisphere, contribute to the COLOSS survey which is significantly larger scale. The most recent 2 data published (for the ’16/’17 winter) had data from ~15,000 respondents 3 managing over 400,000 hives. Of these, ~21% were lost for a variety of reasons. COLOSS data is presented as an unwieldy table, rather than graphically. Further details, including recently published results, are linked from their website.

In the USA the Bee Informed Partnership surveys losses – both winter and summer – and claims to have results that cover ~10% of all the colonies in the country (so probably between 250,000 and 275,000 hives). Winter losses in the USA are rarely reported at less than 20% and were as high as 35% in the ’18/’19 winter 4.

Bee Informed Partnership annual colony losses

Are these figures to be trusted?

Who knows?

Each survey is accompanied by a variety of statistics. However, since they all appear to be based upon voluntary reporting by a subset of beekeepers, there are opportunities for all sorts of data to be included (and even more to be missed entirely). 

The problem with surveys

Is the successful beekeeper who managed to get all her colonies through the winter more likely to respond?

A form of ‘bragging rights’.

What about the beekeeper that lost all his colonies?

Does he respond out of a sense of responsibility?

Or does he keep quiet because he doesn’t want to be reminded of those cold, quiet, mouldy boxes opened on the first warm day of spring?

One and two year beekeepers

What about the high level of annual ‘churn’ amongst beekeepers? They buy a nuc in May, filled with enthusiasm about the jars of golden honey they’ll have for family and friends in late summer.

To say nothing of all the “saving the bees” they’ll be doing.

But by late summer the colony is queenless and has an unpleasant temperament

Beekeeping should be enjoyable ...

Beekeeping should be enjoyable …

Psychopathic you might say … if you were feeling uncharitable.

Consequently the Varroa treatment goes on far too late,. Or is quietly forgotten. The winter bees have high viral loads and ‘die like flies’ 5, resulting in the colony succumbing by the year end.

But this colony loss is never recorded on any surveys.

The once enthusiastic beekeeper has moved on and is now passionate about growing prize-winning vegetables or cheesemaking or keeping chickens. 

Beekeeping associations train lots of new beekeepers and – although membership numbers are increasing – it’s well below the rate they’re trained at.

Some may not be ‘joiners’ and go their own way.

Many just quietly stop after a year or two.

How many people have you met that say “Oh yes, I used to keep bees”

Did you ask them whether they ever completed a winter losses survey?

I’m not sure any of the surveys listed above do much ‘groundtruthing’ to establish whether the data they collect is truly representative of the population actually surveyed. With large numbers of respondents spread across a wide geographic and climatic range it’s not an easy thing to do.

So, treat these surveys with a healthy degree of scepticism.

Undoubtedly there are high levels of winter losses – at least sometimes – and the overall level of losses varies from year to year.

Losses and costs

The direct financial cost of these colony losses to beekeepers is very high.

Ignoring time invested and ‘consumables’ like food, miticides and foundation these costs in ’16/’17 for just Austria, the Czech Republic and Macedonia were estimated at €56 million 😯  

These figures simply reflect lost honey production and the value of the lost colonies. They do not include the indirect costs resulting from lost pollination.

But, for the small scale beekeeper, these economic losses are irrelevant.

Most of these beekeepers do not rely on bees for their income.

The real cost is emotional 🙁

It still saddens me when I lose a colony, particularly when I think that the loss was avoidable or due to my incompetence, carelessness or stupidity 6.

Little snow, big snow. Big snow, little snow.

Your hives should be quiet in winter, but it hurts when they are silent in spring.

Anatomy of a death

The COLOSS surveys give a breakdown of winter losses in three categories:

  • natural disasters
  • queen problems
  • dead colonies

Natural disasters are things like bears, honey badgers, flooding or falling trees.

We can probably safely ignore honey badgers in the UK, but climate change is increasing the weather extremes that causes flooding and falling trees.

Moving to higher ground ...

Moving to higher ground …

Don’t assume that poly hives are the answer to potential flooding.

They do float, though not necessarily the right way up 🙁

Queen problems cover a variety of issues ranging from reduced fecundity to poor mating (and consequent drone laying) to very early or late – and failed – supersedure 7.

Beekeepers with a lot more experience than me report that queen problems are increasing.

Drone laying queen ...

Drone laying queen …

Perhaps the issues with fecundity and drone laying are related to toxic levels of miticides in commercial foundation? It’s certainly known that these residues reduce drone sperm fertility significantly. I intend to return to this topic sometime during the approaching winter … perhaps in time to encourage the use of some foundationless frames for (fertile) drone production 😉

In the ’16/’17 COLOSS data, natural disasters accounted for 1.6% of all overwintered colonies (so ~7.5% of losses), queen problems resulted in the loss of 5.1% of colonies (i.e. ~24% of losses) and the remainder (14.1% of colonies, ~68% of losses) just died.

Just died?

We’ll return to natural disasters (but not bears or honey badgers) and queen problems shortly. What about the majority of losses in which the colony ‘just died’?

If you discuss colony post-mortems with beekeepers they sometimes divide the ‘just died’ category (i.e. those not readily attributable to failed queens, marauding grizzlies or tsunamis) into four groups:

  • disease
  • isolation starvation
  • starvation
  • don’t know 

The most important disease associated with overwintering colony losses is high levels of Deformed wing virus (DWV). This results from uncontrolled or inadequately controlled Varroa infestation. For any new readers of this site, please refer back to many of the articles I’ve already written on Varroa management 8.

I strongly suspect that a significant proportion of the reported isolation starvation is actually also due to disease, rather than isolation per se.

A consequence of high levels of DWV is that winter bees die prematurely. Consequently, the colony shrinks faster than it would otherwise do. It starts the size of a basketball but (too) rapidly ends up the size of a grapefruit … or an orange.

Isolation starvation and disease

The small cluster is then unable to remain in contact with stores, and so starves. 

Yes, the colony died from ‘isolation starvation’, but the cause was the high levels of Varroa and the viruses it transmits.

Isolation starvation ...

Isolation starvation …

What about regular starvation?

Not because the cluster became isolated from the stores, but simply because they had insufficient stores to get through the winter.

Whose fault was that?

And the last category, the “don’t knows”?

I bet most of these are due to high levels of Varroa and DWV as well 🙁

Yes, there will be other reasons … but probably not a huge number. 

What’s more … if you don’t know the reason for the colony loss there’s very little you can do to mitigate against it in future seasons.

And, other than wild and increasingly vague speculation, there’s little I can write about if the reason for the loss remains unknown 9.

Avoiding winter losses

So, let’s rationalise those earlier lists into the probable (known) major causes of overwintering colony losses:

  • natural disasters
  • queen problems
  • starvation
  • disease (but probably mainly DWV and Varroa

As the long, hot days of summer gradually shorten and cool as early autumn approaches, you should be thinking about each of these potential causes of overwintering colony loss … and doing what you can to ensure it doesn’t happen to you (or, more correctly, your bees).

Ardnamurchan autumn

Ardnamurchan autumn

Some are easier to deal with than others.

Here’s a whistle-stop tour of some more specific problems and some practical solutions 10. Some, all or none may apply to your bees – it depends upon your location, your climate, your experience and future plans as a beekeeper. 

Natural disasters

These fall into two broad groups:

  • things you can do almost nothing about (but might be able to avoid)
  • things you can relatively easily solve

Flooding, falling trees, lightning, landslides, earthquakes, volcanoes, meteor strikes etc. all fall into the first group.

If you can avoid them, do. 

Your local council will have information on areas at risk from flooding. There are also searchable maps available from SEPA. Do not underestimate the severity of some of the recent flooding. Some parts of Scotland and Northern England had 600 mm of rain in two days in 2015.

You might be surprised (and from an insurance aspect, devastated) at the classification of some areas now ‘at risk’. 

Where did Noah keep his bees? In his Ark hive.

Where did Noah keep his bees? In his Ark hive.

Consider moving hives to higher ground before the winter rains start. One consequence of climate change is that heavy rainfall is now ~20% heavier than it was a few decades ago. This means that floods occur more frequently, are more extensive and the water levels rise faster. You might not have a chance to move the hives if flooding does occur,

More rain and stronger winds (particularly before leaf fall) mean more trees will come down. You might be able to identify trees potentially at risk from falling. It makes sense to remove them (or site your hives elsewhere). 

No risk of this larch tree falling on my hives

Lightning, earthquakes, volcanoes, meteor strikes … all a possibility though I would 11 probably worry about Varroa and woodpeckers first 😉

Solvable natural disasters

The ‘solvable’ natural disasters include preventing your colonies being robbed by other bees or wasps. Or ransacked by mice or woodpeckers after the first hard frosts start. A solution to many of these are ‘reduced size entrances’ which either enable the colony to better defend itself, or physically restricts access to critters.

The L-shaped ‘kewl floors‘ I use prevent mice from accessing the brood box. They are also easier for the colony to defend from bees/wasps, but can also easily be reduced in size with a narrow piece of hardwood. If you don’t use these types of floor you should probably use a mouseguard.

Polyhives and polythene

Polyhives and polythene …

Woodpeckers 12 need to cling onto the outside of the hive to hammer their way through the side. You can either place a wire mesh cage around the hive, or wrap the box in something like damp proof membrane (or polythene) to prevent them gaining purchase on the side walls.

Keep off Woody

Keep off Woody

Doing both is probably overkill though 😉

Strong colonies

Before we move onto queen problems – though it is related – it’s worth emphasising that an even better solution to prevent robbing by bees or wasps is to maintain really strong colonies.

Strong colonies with a well balanced population of bees can almost always defend themselves successfully against wasps and robbing bees.

Nucs, that are both weaker and – at least shortly after being made up – unbalanced, are far less able to defend themselves and need some sort of access restriction.

By ‘balanced’ I mean that the numbers and proportions of bees fulfilling the various roles in the nucleus colony are reflective of a full hive e.g. nurse bees, foragers, guard bees. 

Reduced entrance ...

Reduced entrance …

But the benefits of strong colonies are far greater than just being able to prevent wasps or robbing bees. There is compelling scientific evidence that strong colonies overwinter better

I don’t mean strong summer colonies, I mean colonies that are strong in the late autumn when they are fully populated with the winter bees.

Almost the entire complement of bees in the hive are replaced between late summer and late autumn. Remember that a really strong summer colony may not be strong in the winter if Varroa and virus levels have not been controlled.

How do you ensure your colonies are strong?

  1. Minimise disease by controlling Varroa levels in early autumn to guarantee the all-important winter bees are reared without being exposed to high levels of DWV.
  2. Try and use a miticide treatment that does not reduce the laying rate of the queen.
  3. Avoid blocking the brood nest with stores where the queen should be laying eggs.
  4. Requeen your colonies regularly. Young queens lay more eggs later into the autumn. As a consequence the colonies have increased populations of winter bees.
  5. Unite weak colonies (assuming they are disease-free) with stronger colonies. The former may well not survive anyway, and the latter will have a better chance of surviving if it is even stronger – see below. 
  6. Use local bees. There’s good evidence that local bees (i.e. reared locally, not imported from elsewhere) overwinter better, not least because they produce stronger colonies.

Uniting – take your losses in the autumn

My regular colony inspections every 7-10 days during May and June are pretty much abandoned by July. The risk of swarming is very much reduced after the ‘June gap’ in my experience. 

I still check the colonies periodically and I’m usually still rearing queens. However, the rigour with which I check for queen cells is much reduced. By July my colonies are usually committed to single-mindedly filling the supers with summer nectar.

They are already making their own preparations for the long winter ahead.

Although the inspections are less rigorous, I do keep a careful watch on the strength of each colony. Often this is directly related to the number of supers I’ve had to pile on top.

Colonies that are underperforming, and – more specifically – understrength are almost always united with a stronger colony.

An Abelo/Swienty hybrid hive ...

An Abelo/Swienty hybrid hive …

Experience has taught me that an understrength colony is usually more trouble than it’s worth. If it’s disease-free it may well overwinter reasonably well. However, it’s likely to start brood rearing more slowly and build up less well. It may also need more mollycoddling 13 in the autumn e.g. protection from wasps or robbing bees.

However, a colony that is not flourishing in the summer is much more likely to struggle and fail during the winter. Perhaps the queen is not quite ‘firing on all cylinders’ and laying at a really good rate, or she might be poorly mated.

Far better that the workforce contributes to strengthening another hive, rather than collect an underwhelming amount of honey before entering the winter and eventually becoming a statistic.

My winter losses are low and, over the last decade, reducing.

That’s partly because my Varroa management is reasonably thorough.

However, it’s probably mainly due to ensuring only strong colonies go into the winter in the first place.

Newspaper

I’ve dealt with uniting in several previous posts.

It’s a two minute job. 

You remove the queen from the weak colony, stack one brood box over the other separated by a sheet or two of newspaper with a very small (~3mm) hole in the middle. Add the roof and leave them to get on with things.

I don’t think it makes any difference whether the strong colony goes on the top or the bottom.

I place the colony I’m moving above the box I’m uniting it with. My – wildly unscientific – rationale being that the bees in the top box will have to negotiate the route to the hive entrance and, in doing so, will help them orientate to the new location faster 14.

If you unite colonies early or late in the day most foragers will be ‘at home’ so not too many bees will return to find their hive missing.

If there are supers on one or both hives you can separate them with newspaper as well. Alternatively, use a clearer the day before to empty the supers prior to uniting the colonies. You can then add back the supers you want and redistribute the remainder to other hives in the apiary.

Successful uniting ...

Successful uniting …

Don’t be in too much of a hurry to check for successful uniting.

Leave them a week. The last thing you want is for the queen to get killed in an unseemly melee caused by you disturbing them before they have properly settled.

Done properly, uniting is almost foolproof. I reckon over 95% of colonies I unite are successful.

That’s all folks … more on ‘Cutting your losses’ next week 🙂


Notes

At just over 3000 words this post got a bit out of control … I’ll deal with more significant queen problems, feeding colonies, the weather and some miscellaneous ‘odds and sods’ next week.