Category Archives: Queen rearing

Bad behaviour

Synopsis : Bad behaviour by bees – aggression, following and stability on the comb – may be transient or permanent. To recognise it you need to keep records and have hives to compare. Fortunately, these traits are easy to correct by requeening the colony.

Introduction

That’s a pretty generic title and it could cover a multitude of sins.

Slapdash disease management, insufficient winter feeding, poor apiary hygiene, siting bait hives near another beekeeper’s apiaries … even bee rustling.

However, I always try and write about a topic from direct practical experience.

If I did ever exhibit any of those examples of bad behaviour:

So, instead of discussing bad behaviour by beekeepers, I’ll write about badly behaved bees.

Nice bees

Most beekeepers have an idea of what ‘nice bees’ are like. It’s a 2 term that encapsulates the various characteristics that a beekeeper values.

These characteristics could include temper, stability on the comb, productivity (in terms of either/both bees or honey), frugality, colour and any number of other terms 3 that define either the appearance or behaviour of individual bees or, collectively, that of the colony.

Of course, all these terms are relative.

Nice bees and a nice queen

My definition of aggressive bees may well differ from what another beekeeper would consider (un)acceptable.

The relatively calm and stable bees in most of my hives could be defined as ’running about all over the place’ by someone who’s bees stick, almost immobile, to the comb.

This relativity is nowhere more apparent than when visiting the apiary of another beekeeper. I’m always a little wary of someone donning a beesuit 100 metres from the hives 4 while simultaneously claiming their bees are ’very friendly’.

These differences don’t matter if you keep your bees in an isolated location where other people – in particularly civilians (i.e. members of the general public) – won’t be impacted if your ’friendly bees’ are actually ’murderous psychopaths’.

However, they do matter if your bees are in an urban garden, or a shared allotment.

They also matter when making comparisons between colonies to determine which to split (so creating a new queen) and which – perhaps urgently – need requeening.

Transient or permanent?

For the purpose of the following discussion let’s consider that the ‘bad behaviour’ is aggression.

Here’s a screenshot from a YouTube video (from CapLock Apiaries) which shows some really unpleasant bees. The final words (in this part of the video) by the beekeeper on the right is ”This queen has to die!”.

‘This queen has to die’ … beekeeping doesn’t have to be like this

The brood boxes were stuck together, presumably because the colony is less regularly inspected and everything gets gummed up with propolis. The first comment 5 was

I’m new to bees and thought I found a hot wild hive today. Went to youtube to find some comparison. The hive I saw was absolutely docile in comparison to these guys, and the first wild hive I extracted are absolute angels!

Which emphasises the relative nature of behaviour.

I dislike aggressive bees so have no videos of my own showing this sort of behaviour 6.

However, that doesn’t mean that my bees never show aggression … 😉

Weather, forage, handling, queenless … all can influence temper

Aggression – or defensiveness – can be a permanent feature of a colony or can appear transiently. In my view, the former is unacceptable under any circumstances 7.

However, in response to environmental conditions or handling, a colony may become defensive. Again, the amount of ‘aggro’ varies. Some bees may just buzz a little more excitedly, others can go completely postal. If you are careful to only select from your better behaved stocks for splits and queen rearing you can usually avoid even transient unpleasantness.

Environmental factors that can influence the behaviour of a colony include the weather, the availability of forage and the gentleness and care exhibited by the beekeeper during inspections.

Queenless colonies may also be more aggressive, but all the comments in the post this week relate to queenright colonies.

Scores on the doors

There are two easy to achieve solutions that allow a beekeeper to make sense of the variation in any of these traits. These are:

  • keeping good hive records to allow undesirable behaviour, or a gradual decline in behaviour, to be identified, and
  • managing more than one colony so comparisons can be readily made

I score temper, running (stability on the comb) and following, but I know some who record a much greater range of characteristics.

Each are recorded on a 1 – 5 scale (worst to best, allowing half points as a ‘perfect 5’ is unattainable as the bees can always be better, whereas a 4.5 is a really good colony).

The bees in hive #34 run all over the place. They are being requeened.

I also make a note of the weather. A colony may consistently score 4’s or better until you inspect them in a thunderstorm, but that’s OK because when you look back you’ll see that the conditions were woeful.

Compare and contrast

With just one colony you have no reference to know whether all colonies in the area are suffering because there’s a dearth of nectar, or if this colony alone is a wrong ‘un.

With two colonies things get easier.

Increasingly – for reasons I’ll discuss in a future post – I think three is probably the minimum optimum number.

The more you have the easier it is to identify the outliers … the exceptional (whether good 🙂 or bad 🙁 ). That should be qualified by stating the more you have in one location as the local environment may differ significantly between apiaries.

The great thing about hive records is that they provide a longer retrospective view. You can overlook the hammering you received from a colony last week 8 if there are a long list of 4’s over the last 3 months.

They also allow you to observe trends in behaviour.

Growing old disgracefully

I’ve recently noticed that a couple of my colonies are markedly less well behaved now we’re reaching mid-season than they were throughout 2021 or the beginning of this year. I think at least one has (actually had, as it was requeened last week) a 2020 queen.

As the queen ages the behaviour of the colony has gradually changed.

I crudely classify my colonies into thirds – good, bad or indifferent. Anything ‘bad’ is requeened as soon as I have a suitable queen available (or the larvae to rear one).

These ‘declining’ colonies were never worse than indifferent last year but, as they’ve expanded this spring, are now firmly in the ‘bad’ category. I presume this is consequence of the combination of the influence of the queen’s pheromones and the size of the colony 9.

Whatever … I think all it really demonstrates is that consistently taking even cursory hive records is useful.

The colonies I’m referring to above haven’t become more aggressive (though this can happen). The characteristic I’ve seen change the most is the steadiness of the bees on the comb.

It’s worth noting here that colony size can fundamentally impact behaviour. A well-tempered nuc can develop into a big, strong and unpleasant colony. In contrast, the nucs I prepare from ‘indifferent’ colonies during swarm control and requeening don’t appear to generally improve much in temperament.

If I’m conducting swarm control on the third ‘bad’ tirtile 10 the queen is despatched so I never get to experience the performance of the resulting nucleus colony 😉

Aggression

I’ve discussed aggression above and covered it in more general terms previously. There are several studies of the genetics of aggression, usually by GWAS (Genome Wide Association Studies) of Africanised bees which can be significantly more bolshy than anything I’ve encountered in the UK 11. The colony shown in the video cited above is Africanised.

A recent study analysed individual aggressive bees 12 and compared them with pollen-laden foragers from the same colony. However, they failed to identify any genetic loci associated with aggression.

In contrast, by ‘averaging’ the genetics of hundreds of aggressive or passive (forager) bees, the scientists identified a region of the genome that – if originating from European honey bees – was more likely to result in gentle bees. Conversely, if this region is Africanised, the colony was more likely to be aggressive 13.

Hive genetics, not individual genetics

This is a really interesting result 14 as it means that, even if individual bees are Africanised and potentially aggressive, if the majority of the colony is European-like (and so gentle) the individual Africanised bees are unlikely to be aggressive.

Aggression is therefore a consequence of hive genetics, rather than individual genetics.

Neat.

Aggression in psychotic UK colonies (which, by definition, are not Africanised) may have a different genetic explanation, though some of the genes involved may be similar. Since aggression can manifest itself in several different forms – jumping up from the frames, buzzing around your head, response to sudden movement, targeting dark colours etc. – I suspect there may be multiple genes involved in the sensing or threat response.

Following

Some aggressive bees – particularly those that buzz agitatedly around your head during an inspection – also have the profoundly unpleasant trait of following you out of the apiary … down the track … back to the car … or even into the house.

The car is packed, you’ve taken you beesuit off … and PING!

The very worst of these lull you into a false sense of security by flying off, only to return in a lightning-fast kamikaze strike as soon as you remove your veil.

Ouch, that hurt.

I consider ‘following’ a worse trait than overt aggression at the hive.

I’m suited and booted’ at the hive. Ready for anything … ’Come on if you think you’re hard enough’.

At least, I am if I’ve remembered to zip my veil up properly 😉

But 15 minutes later, when I should be contemplating a cuppa, I don’t want to be pestered by bees dive bombing my head.

Looking for trouble

Followers don’t necessarily just follow.

They can initiate long-range and unprovoked attacks on individuals just walking near the hive.

I think this is an example of bad behaviour that should not be tolerated.

If you think it’s bad as a beekeeper, just imagine how unpleasant it is for passers by.

Sometimes it’s difficult to identify which of several hives is showing this trait in an apiary. To confirm it, change the order of hive inspections, leaving the likely suspect to last. If the followers don’t appear until the final inspection you have your answer.

If they’re present before that you either guessed wrong or – Eek! – have more than one hive behaving badly.

I’ve seen many aggressive colonies that showed little or no tendency to follow. Conversely, I don’t remember seeing followers that were not from an aggressive colony. I presume this means that the genes involved are distinct but linked.

Whether different or not … they’re unwanted. Any colonies of mine showing overt aggression or following are requeened. Perhaps 5% of my colonies each season are requeened for this reason.

Running

Remember back to your early days of beekeeping when you had to ’find the queen’ and were faced with this … 15

Find the queen

I estimate there are about 1200-1300 bees on the face of that frame 16. There are the same amount on the other side.

All of the bees are moving.

Of course, this makes it much easier to find the queen as she moves differently to the workers on the frame. I’m probably not alone in sometimes struggling to ‘find the queen’ on a photograph of a frame when I rarely have trouble locating her on a frame in my hands 17.

However, the more the workers move, the more difficult it gets.

Spot the queen

See if you can spot the queen on this frame of relatively sedate bees:

And what about this frame of more mobile bees? It’s worth noting there are only about half the total number of bees on this second frame.

OK, I cheated. Only the first frame has a queen on it. She’s in the middle near the bottom of the frame, moving left to right 18.

The top frame is pretty standard in terms of ‘running’ (shorthand for the stability of bees on the frame) in my hives. The bottom video is nothing like the worst I’ve seen, but (if consistently like this) it’s certainly a reason to score the colony down and requeen them from a more stable line.

Inspections

Bees running around on the frame certainly make locating the queen more tricky.

However, as I’ve written elsewhere, you don’t need to find the queen unless you need to do something with her. The presence of eggs is usually sufficient to tell you the colony is queenright (assuming there are no big, fat queen cells or a queen corpse on the open mesh floor 🙁 ).

The reason I dislike bees that are not stable on the comb is because they make inspections more difficult. They prevent you clearly seeing eggs and larvae so you have to shake the bees off the frame, thereby overloading the next frame you look at with agitated bees.

Furthermore, the bees must have somewhere to run to … which usually means they run onto the frame lugs, and then your hands and – in the worst cases – up your forearms.

There was a frame lug there a few seconds ago

In addition, they run over each other, forming heavier and heavier ‘gloops’ 19 of bees that eventually become too heavy, lose their grip and fall … onto the top bars of the frames you have yet to inspect, onto the ground, or into the top of your boots.

A ‘gloop’ forming

Running appears to be a feature which isn’t influenced much by environmental conditions, perhaps other than a chilly and gusty wind 20.

Better bees

There are two good things about aggression, following and running:

  • these behaviours are easy to identify; you can easily tell if the colony is too hot for comfort, or if your neighbour complains repeatedly about getting chased by bees, or you’re plagued with ‘gloopy’ bees that make inspections a pain. Remember, there’s no standard to compare them to, no ‘reference colony’. All that matters is how they’re viewed by anyone that interacts with them. If they’re too defensive, if they bother you away from the hive or are too mobile, then score them down in your hive records. If they remain the same for the next two to three weeks, or don’t improve when the weather/forage picks up, then make plans to do something about it.
  • all these undesirable traits can be easily corrected by replacing the queen. Four to six weeks after requeening the characteristics of the colony will reflect those of the new queen. Of course, this only works if you source a good quality queen – either by rearing your own or purchasing one 21, or by ensuring that the colony raises its own queen from larvae sourced from a high quality colony. While you’re at it do yourself and your neighbouring beekeepers a favour and fork out any drone brood in the misbehaving colony.

It really is as easy as that.

Incremental but steady improvement

Over a few years the quality of your bees will improve.

Of course, with open mating you’ll occasionally get rogue colonies. However, as the average quality improves, you’ll have a greater choice of colonies from which to source larvae.

Over time you’ll need to recalibrate your scoring system. In five years a 3/5 will be a much improved colony over a 3/5 now.

When you next (reluctantly) open a bolshy colony, struggle to find the queen because of the wriggling mass of bees on the frames and are then stung repeatedly as you take your veil off by the car, think of it as an opportunity.

You have now recognised the problem and you already know the solution 😉


Note

I’ve chosen aggression, following and running as three easy to spot traits that can be, just as easily, fixed. There are other examples of bad behaviour that may well be unfixable. There’s a dearth of nectar in my west coast apiary until the lime flowers and robbing is a problem 22. Although robbing is a variable characteristic (amongst different strains of bees) I doubt it could be excluded completely by requeening. Selection would be time consuming, being dependent upon environmental conditions. However, the ‘fix’ is again relatively straightforward … keep very strong colonies, feed late in the evening (if needed) and physically protect colonies with reduced entrances and/or robbing screens. Robbing is an example of bad behaviour by bees where the solution is almost entirely the responsibility of the beekeeper.

More queen rearing musings

Synopsis : What happens when your queenright cell raiser swarms? Are cells being reared under the supersedure response doomed? This and other musings on miscellaneous aspects of queen rearing, together with some comments on clearing supers on queenless hives.

Introduction

I described queen rearing last week as The most fun you can have in a beesuit ™. That’s my opinion. You may prefer making candles, or beeswax wraps or extracting and jarring honey 1 and I wouldn’t argue, though none of them come close to the satisfaction I get from queen rearing.

The term ‘queen rearing’ sometime conjures up images of booming, chest-high queenless cell starters, dozens of grafted larvae on each cell bar frame, incubators and serried rows of mini-nucs waiting for virgins … or even clinical instrumental insemination apparatus.

Capped queen cells

Capped queen cells on a cell bar frame (produced using the Ben Harden queenright queen rearing approach)

This is the industrial scale production of queens, and it’s rare that enthusiastic but nevertheless small-scale amateur beekeepers need that number of queens.

Or have the resources to produce them.

For convenience I think of queen rearing as an activity that can occur at three different scales:

  1. One or two queens at a time – e.g. adding a frame of selected (i.e. good quality) eggs/larvae to a terminally queenless hive. Surplus cells can be cut out and distributed elsewhere.
  2. Five to ten at a time – often using selected larvae transferred to a cell starter colony by grafting, a Cupkit-type system, cell punching or (fewer manipulations still) the Miller or Hopkins methods.
  3. Dozens of queens at a time – almost always using grafting and a strong queenless cell starter colony.

I’ve run 10-20 colonies for a decade or more and rarely need more than 20 queens a season (a number which includes some spares to make up nucs).

In addition, I live in an area with variable (i.e. often poor) weather where queen mating can be ’hit and miss’.

Little and often

For these reasons I prefer to produce a few queens at a time so I don’t have to devote significant resources to an activity that might be thwarted by a month of lousy weather.

I’d rather try and produce half a dozen queens three or four times a season, than dozens at once.

The latter requires a major commitment of resources (colonies and equipment). Depending upon the weather I might end up with a glut of queens.

Or an apiary-full of laying workers 🙁

In contrast, the methods I use allow me to produce a handful of queens every few weeks. If the weather is kind, all will get mated. If not, it’s not a total disaster.

West coast weather, mid-May to mid-June 2022 (average 13°C, range 6.2°C to 23.9°C)

Over the last month we’ve only had 2-3 days with conditions normally associated with successful queen mating i.e. light winds, sunshine and temperatures of 20°C.

Predicting this type of ‘weather window’ 2-3 weeks in advance is almost impossible.

It’s better to be prepared to repeat things again.

And again 😉

Apiary vicinity mating

In fact, queens don’t need ‘perfect’ conditions for mating. If they did, sustainable beekeeping 2 would be impossible – or at least very difficult – in many northern latitudes. Queens can be successfully mated in sub-optimal conditions 3.

Part of my interest in monitoring the local weather at my apiary is to try and determine just how poor the conditions can be whilst still getting queens mated.

Native Apis mellifera mellifera (black bees) are reported to use apiary vicinity mating (AVM) and so may not need optimal conditions to fly to distant drone congregation areas. Jon Getty has written more about AVM on his website.

However, wherever or whenever they get mated, I prefer to produce repeated batches of queens using queenright cell raisers. By doing this I’m not putting all my ‘eggs in one basket’. Essentially these cell raisers are standard (honey) production hives manipulated in simple ways to provide the conditions needed to rear suitably-presented larvae as queens.

And inevitably, because they’re queenright, things can sometimes go wrong 🙁

Queenright queen rearing

The two methods I’ve used are the Ben Harden approach and a Morris board. Both use a single colony to start and finish the queen cells, and the queen remains present – albeit separated from the developing cells – throughout the 10-12 days from grafting until the cells are used.

The Morris board

A Morris board is essentially the same as a Cloake board. These are boards that separate the queenright lower brood box from an upper brood box in which the queen cells are produced. The board has an integrated queen excluder and the provision to separate the upper and lower box with a metal or plastic divider.

Morris board (lower side)

With the divider inserted queen cells are started in the top box under the emergency response. However, once started, the divider is removed and the cells are finished under the supersedure response.

The Morris board is more complicated than a Cloake board; it is used with a divided upper brood box – allowing separate batches of cells to be started every week or so – and has a series of doors for bleeding off and redirecting returning foragers to the correct compartment.

It’s a clever idea and one that shows considerable promise for my queen rearing.

I’ll write more about my use of a Morris board in due course, or you could track down the article Michael Badger wrote in Bee Craft.

The Ben Harden approach

I’ve discussed the Ben harden approach extensively already – try here for starters. The method, although perhaps popularised by the eponymous Irish beekeeper (and excellent instructors like the late Terry Clare) was also described nicely by the National Bee Unit’s Mike Brown and David Wilkinson twenty years ago in the American Bee Journal 4.

Preliminary setup for Ben Harden queen rearing (note the ‘fat dummies’ occupying much of the upper box)

Until the last couple of years this is the method I’ve used for most of my queen rearing.

The queen is confined below a queen excluder to the lower brood box. Grafted larvae are added to the upper box, space within which is often restricted by the use of ‘fat dummies’.

The queen cells are therefore started and finished under the supersedure response.

Supersedure vs. swarming responses and colony swarming

In preparation for swarming a colony naturally produces several charged queen cells 5. Assuming the weather is suitable, the colony usually swarms on the day that the first cells are sealed.

If the weather is poor then swarming is delayed, but they often then go at the first opportunity … so much so that even a borderline day after a period of poor weather during the normal swarming season is often characterised by lots of swarms.

In contrast, newly sealed supersedure cells – and these are usually very few in number (often just one) – are incubated for a further 8 days until emergence of the virgin queen.

The superseding colony does not swarm.

The new queen goes on a few mating flights and starts laying.

At some point after that the old queen simply disappears.

One day you’re surprised to find two laying queens in the hive but at the next inspection (or the one after that) only the shiny new one remains.

The queen is dead, long live the queen.

Advantages (and disadvantages) of queenright queen rearing methods

For the small scale beekeeper – perhaps 2-20 colonies – queenright methods offer a number of advantages (with a few disadvantages) for queen rearing:

  • the quality of the cell starter/finisher is immaterial as long as the colony is strong. You simply provide it with larvae from good quality stock.
  • no interruption 6 to nectar collection. In a good nectar flow you simply keep piling on supers as needed and the bees raise the cells and fill the supers.
  • if there’s no nectar flow you will have to feed the colony, so you must remove any supers to avoid tainting any stored nectar with syrup.
  • if you do simultaneously use the colony for honey production and cell raising the hive can get tall and heavy. Mind your back.
  • you can use a single hive for the entire process if needed; cell starter, sourcing larvae, cell finisher and populating mini-nucs. You might even get some honey as well 😉 7

The queenright methods outlined above exploit the supersedure response for cell raising. This means that the colony will not swarm in response to capping of the cells in the upper box.

But …

That is not the same as saying that the colony will not swarm 🙁

Don’t forget, there’s a laying queen in the bottom box. She will continue to lay while the new cells are being started, fed, nurtured and sealed.

And if she runs out of space the colony can still make swarm cells in the bottom box and so may swarm.

Here are a couple of examples where this has happened … and the consequences for my queen rearing.

A swarming Ben Harden cell raiser

When I lived in the Midlands I routinely started queen rearing during April. Queens produced in April could be mated as early as the first week of May in a good year, and occasionally, even earlier.

Colonies got a massive boost during this part of the season from the oil seed rape. The photo below is from the 19th of April 2014.

Mid-April in the apiary ...

Mid-April in a Warwickshire apiary …

When rearing queens using the Ben Harden approach during a strong nectar flow you can safely relocate the upper brood box above the top super. In a busy hive the developing cells still get more than enough attention.

In addition, this can help increase ‘take’ 8 by reducing the concentration of queen pheromones due to the separation of the bottom brood box (containing the original queen) and the box containing the grafted larvae.

When using this method it is important to check the upper box for queen cells on the day the grafts are added. This box, being separated from the queen-containing brood box, has reduced queen mandibular, and no queen footprint, pheromones.

Consequently, it’s not unusual for the bees to start drawing queen cells. These must be destroyed or – being more advanced than the grafted larvae – they will emerge first and destroy all your hard work.

I had done this and added the grafts which, on checking 24 hours later, had all been accepted.

Chipmunks are Go! 9

Out of sight is out of mind

However, I had failed to check the bottom box for queen cells on the days before I added the grafted larvae.

The colony promptly swarmed, probably before the newly developing queen cells were capped.

This was either before I routinely clipped my queens, or I’d missed this particular queen. Whatever, she and a significant proportion of the bees disappeared to pastures new.

I can’t remember how (or when) I realised the colony had swarmed. It might have been reduced entrance activity during the strong OSR nectar flow, or I might have just (finally!) conducted a regular inspection.

The bottom box contained sealed queen cells, no queen and no eggs 🙁

But, all was not lost.

The cells containing grafted larvae were capped and looked good. They’d clearly received sufficient attention 10 and I was therefore hopeful they’d emerge, mate and produce usable queens.

And they did.

I knocked back all the sealed queen cells in the bottom box and then – on the day I used the cells from the grafted larvae – added one of the latter to the lower brood box.

I removed the queen cells in the lower box for two reasons:

  • it prevented a new queen emerging there while I had cells above the queen excluder, and
  • it allowed me to use a cell raised from larvae sourced from a better quality colony.

So, a swarming cell raiser isn’t necessarily a disaster.

A more recent, but less successful, attempt

My first attempt at queen rearing this season involved using a Morris board.

I added the Morris board and upper brood box on the 18th of May. I then did all of the necessary Morris board manipulations – closing the slide, opening entrances, closing others – to pack the upper box with bees.

On the 25th I did the grafting and – at the same time I added the grafts on the cell bar frame – I destroyed a small number of queen cells in the upper box 11.

On the following day 7-8 of the larvae had been accepted and the cells were capped on or around the 30th.

Cell bar frame festooned with bees

I was off beekeeping elsewhere so didn’t check the hive again until the 1st of June … and was dismayed to find all of the cells had been torn down.

Torn down queen cells. The cell on the right has a gaping hole on the opposite face.

There was no queen in the upper box and the queen excluder was intact. The cells appear to have been torn down by workers. I’ve had this happen before when there’s been a dearth of nectar, but this box was getting 300 ml of thin syrup every 48 hours.

D’oh!

Of course, I eventually checked the bottom box and found:

  • one vacated queen cell. This cell was situated on the lower edge of one of the central frames.
  • a virgin queen running about and no sign of the original clipped and marked queen 🙁

The single queen cell might suggest supersedure. However, its position (though far from a reliable indicator) was more like that of a swarm cell.

A vacated queen cell

In addition, the absence of eggs or any sign of the original queen, strongly suggested that the colony had swarmed. This probably happened – coincidentally – on the day the cells containing the grafts were sealed.

I say ‘coincidentally’ because I suspect the swarming was triggered by emergence of the new queen in the lower box and had nothing to do with my grafted larvae. That would fit with two things – the timing of the previous inspection (18th) and the fact that swarming is delayed when the incumbent queen is clipped.

However, because she was clipped, the colony was not depleted of workers. The original queen was lost, but that was all.

An alternative interpretation would be that the new queen simply did away with the original queen.

But why were the cells containing grafted larvae torn down?

One possibility was that the new queen pheromones were sufficiently strong that the workers realised they didn’t need additional queens. Alternatively – though she wasn’t by the time I saw her – I suppose there’s a possibility that the virgin queen was small enough to squeeze through the queen excluder, slaughter the developing queens, and squeeze back down to the lower box.

Learning from my mistakes 12 

Both examples above were due to my not maintaining a proper inspection schedule on the lower, queenright, brood box.

Guilty, m’lud.

Despite the advantages outlined above, cell rearing colonies should still be treated in the same way – vis-à-vis regular inspections – as any other production hive.

Other than forgetfulness, sloth and stupidity 13 there’s no reason not to inspect the lower brood box properly on a 7 day cycle.

Once the larvae are accepted you can remove the upper box (and all the bees it contains), gently set it aside and go though the bottom box. The workers with the developing queen cells will look after them for the 10 minutes or so this takes.

Conversely, there’s no reason to interfere with the upper box other than to check acceptance and confirm, in due course, that the cells are sealed. If you assemble the queenright cell rearing colony and wait a week before adding grafts to the upper box (as described above) they cannot start new queens from anything other than the larvae you add.

What else would you be looking for?

Just one more thing 14

There were several comments last week about honey production in queenless colonies.

I collected more supers on Monday containing spring honey. This included recovering supers from several queenless (or currently requeening – some may have contained virgins) colonies.

I have previously noticed that supers are cleared less well – using my standard clearer boards overnight – from queenless colonies.

A not-cleared-as-well-as-I’d-like super above a queenless colony

You always get a few bees remaining in the super, but there were consistently lots more in queenless colonies.

I didn’t count them … few is less than some, which is quite a bit less than lots, which – in turn – is appreciably less than ‘did I put the clearer on inverted?’

This was the second batch of supers I’d collected, a week after the first. I’d left the supers on longer because:

  • there were too many to transport
  • some still had unripe nectar which failed the ‘shake test’ over a hive roof (see photo below), indicating that the water content was too high to extract without risking the honey fermenting

Unripe nectar is easy to shake out of super frames.

Luring the bees down from the supers

In an attempt to speed up clearing bees from the supers of queenless colonies I added the clearer underneath the full supers, but on top of a wet super from which I’d already extracted honey.

A wet super being used to ‘lure’ bees down from full supers in a queenless colony

This worked well.

The heady smell of honey 15 in the wet super resulted in significantly fewer bees in the cleared supers.

I have to transport these cleared supers ~200 miles back home for extraction. If I had a trailer or a truck a few stragglers wouldn’t normally be an issue.

But I don’t … these supers are in the car with me.

Biosecurity

Actually … stragglers would still be an issue, even with a trailer/truck.

My Fife bees have Varroa (low levels, but it’s definitely present) but my west coast bees do not. I take biosecurity seriously and don’t like finding any bees in the car after the journey.

I also really don’t like finding bees in the car at 65 mph on the A9 … and, if I do, I stop and let them out.

The combination of the better-cleared supers and a sharp thwack on any frames with adhering bees reduced the stowaways to zero.

And the five hour return journey 16 was notable for stellar views of an osprey, a stunning male hen harrier and the sun setting over Creag Meagaidh 🙂


 

 

Queen rearing miscellany

Synopsis : Queen cell selection by the beekeeper or the bees – which is more reliable? Nectar collection  and comb building by requeening colonies. Three miscellaneous queen rearing topics this week.

Introduction

May to July are the busiest months of the beekeeping season for queen rearing 1. We’re fast approaching the halfway point so I thought I’d write about some related topics, rather than rehash previously covered areas, or pen a magnum opus on just one subject.

This forces me to be a bit less expansive. It means you can skip over less intervening text in the (vain?) hope of finding something of interest … 😉

Marked queen surrounded by a retinue of workers.

Here’s one I made earlier …

It also means I should deal with things in less detail.

Alas – I’m writing this introduction after completing the majority of the post – I’ve failed and wrote a lot more than originally intended on the first topic so the miscellany will spill over to next week as well 🙁 .

A loyal listener reader asks …

Fans of Tim Harford’s incomparable More or Less will be familiar with the concept of loyal listeners 2. Since this isn’t a podcast 3 listeners is clearly inappropriate.

Unfortunately, I’ve singularly failed to come up with a synonym for loyal starting with an ‘R’, so losing the all-important alliteration with ‘readers’.

Never mind … let’s get back on topic.

One of the pleasures of writing regularly – other than forever playing catch-up with my bloated email inbox 4 – is corresponding with beekeepers around the country 5. Sometimes this is in the comments section, but it also involves a considerable volume of email … including many questions or requests for help.

As I’ve previously mentioned, sometimes these exchanges are short and sweet.

Q. What’s the recipe for thin syrup?

A. D’oh! 6

In these instances that might be the only correspondence 7 but in other cases there’s a bit of to and fro.

Regular readers 8 will recognise some names repeatedly appearing in the comment sections. Many of the questions asked are interesting and some are challenging 9, forcing me to do some thinking and/or reading.

A few allow me to expand further on a topic that I’ve covered, explaining something I either ‘meant to, but ran out of space/time/caffeine’ … or ‘completely forgot’.

And Maccon Keane, a regular reader 😉 from the West of Ireland asked just such a question in the comments to the post last week about beekeeper vs. worker selection of queen cells.

Does beekeeper selection of emergency cells reduce quality?

Here’s the question in full:

Thank you for a really interesting post. My question is this. Using the nucleus method of swarm control by queen removal and induction of the emergency response the beekeeper has to select a queen cell to head the original colony. From these data there is a one in 20 chance (5%) that the chosen cell will not emerge. This is a problem but low risk. However there is a one in two (50%) chance that the beekeeper will select a cell that the bees would have torn down and therefore actively select a lesser quality queen. For an individual colony this may not be particularly significant but over a few generations this negative selective pressure (50%) against the best quality Queens will rapidly lead to a deterioration in stock compared to that which would have happened had the queen been chosen by the bees themselves. Can you think of any way to avoid introducing this systematic negative selection pressure to ensure we let the bees choose the queen because as you title the piece ‘the bees know best’?

This is something I’d thought about, but I’d run out of space to discuss it.

Let’s agree from the outset that the 5% non-emergence rate is an acceptable failure rate. It will be compounded by a small percentage of queens that fail to mate 10.

The beekeeper can’t do very much about either of these.

But what about the beekeeper having a 50:50 chance of selecting a queen cell that the bees would have torn down?

Will this lead to a deterioration of the quality of the bees over time?

It’s an interesting question.

Why do the workers cull about 50% of developing queens?

If you remember, 50% of emergency cells were torn down and these generally contained lighter and smaller queens.

I suggested, or hinted strongly, at three reasons why the bees might favour large queens 11 :

  • higher fecundity i.e. laying more eggs and/or laying over a longer period
  • increased polyandry (and hence colony fitness)
  • more likely to survive fights with ‘sister’ queens during polygyny reduction

Fecundity

The researchers addressed this by counting the ovarioles and the volume of the spermatheca. There were no differences between the chosen queens or those that would have been culled. This suggests, though it’s not definitive, that all should have been equally fecund (assuming similar numbers of matings etc.).

You could probably measure this (with sufficient energy, time and money) but it’s not a trivial thing to determine 12. I think the similarity in the number of ovarioles and the capacity of the spermatheca is compelling enough 13.

My assumption is that all, or at least the majority, of queens would be sufficiently fecund to successfully head a colony.

There’s a recent paper on genetic and phenotypic variability of queens that might be useful here, but I’ve not had time to read it properly. If and when I do – if relevant – I’ll update things.

Increased polyandry

I suggested that larger, heavier, queens might fly more strongly, and so spend longer in drone congregation areas or visit more DCAs … and thereby mate with more drones. David Tarpy hints at this in one of the papers cited last week (quoting unpublished results.).

However, I don’t think the work was ever published in a peer reviewed paper as I’ve been unable to find it.

That doesn’t mean it’s wrong 14. Again, it would be a time consuming thing to determine. Queen mating numbers are quite variable so there would have to be a very large number of repeats to get statistically compelling results, but it is doable given sufficient time, money and energy.

Of course, larger/heavier queens might fly less strongly. This hasn’t been tested.

Polygyny reduction

I think this trait is essentially irrelevant in the context of our beekeeping.

By definition we cull all but one developing queen, so the one that is selected should never have to fight another queen. However workers may select for this – perhaps to avoid the risk of two queens fighting and both being damaged/killed – but if they do we can safely ignore it.

Are these ‘lower quality’ queens quantifiably worse for beekeeping?

So, of the three potential differences suggested I’d argue we can rule the last out as being irrelevant (for managed colonies), and we can perhaps safely assume that fecundity will be sufficient (assuming the queen mates with enough drones).

Increased polyandry remains an open question.

So, one possibility is that any queen cell should result in a queen that will be good enough, assuming the queen emerges and mates successfully.

A second possibility is that any differences between the ‘high’ and ‘low’ quality queens – selected from a single colony – are so minor that they have little or no material effect on our beekeeping.

Similar, but not quite the same thing.

It’s worth noting that the only size characteristics (measured) that differed were weight and either thorax length or width. Other dimensions e.g. wing length, were similar.

Is there other evidence to suggest that differences are likely to be minor (with regard to beekeeping)?

Capped queen cells

Capped queen cells produced using the Ben Harden queenright queen rearing system

In support of this I’d suggest that grafting day-old larvae would not be so universally (successfully) practised if it routinely generated sub-standard queens.

It doesn’t.

When you graft you’re making the selection after less than 24 hours of larval development. The majority of larvae that develop fully, emerge and mate, make perfectly acceptable queens.

But, from a beekeeping perspective, good quality queens are often defined using alternative criteria.

In fact my definition of a good quality queen might well be different from one that the bees would ‘choose’ … or, for that matter, that Maccon would favour.

Selection of good quality stock

And this is where I think selection does have a big influence.

The traits I favour in my bees – steady on the comb, good temper, no following, frugality etc.vary between my colonies.

I score these traits and preferentially rear queens from the colonies that I consider are my ’best’.

I do this by thirds:

  • My ‘worst’ third are always requeened – as soon as is practical – with queens from larvae from my ‘best’ third.
  • I similarly requeen my ‘middle’ third with similarly-sourced queens if I have enough spare, but am happy to requeen the ‘middle’ third from the ‘middle’ third (so to speak).
  • The ‘worst’ third are never used for queen rearing (or allowed to rear queens from their own larvae). The ‘worst’ third are also discouraged from rearing drones.

If the ‘worst’ third need swarm control I allow them to rear emergency cells, knock them all back a week later – leaving them hopelessly queenless – and then add a frame of eggs/larvae from a better colony.

It’s a guaranteed way to easily improve the quality of your bees.

Which I think pretty much brings me to the end of my answer to Maccon’s question.

In summary … I suspect the difference between queens culled or not by the workers is either irrelevant for our beekeeping, so minor as to be unmeasurable, or swamped by other variables in the mating biology of honey bees (e.g. number of drones available, age of those drones and consequent sperm viability).

Over millennia many factors have resulted in the evolution of the worker selection of developing queens, but over a few ‘honey bee generations’ of managed beekeeping I think we can safely ignore them.

Furthermore, in my opinion, the importance of using a good quality colony as the source of larvae for queen rearing far outweighs the inherent variation in the queens reared from any one colony.

It’s a bit like computing … rubbish in, rubbish out.

Queenless colonies – honey and comb

To close this post on miscellaneous items about queen rearing I thought I’d end with an anecdote and an observation.

The former is supported by little more than my dodgy memory and the latter is backed up by some real science 🙂 .

Foraging efficiency and queenlessness

In Fife the spring honey supers are ready for recovery and extraction. I collected the first batch on Monday and have more to get in a couple of days.

The peak nectar flow seems to have been in the last fortnight of May. Much of it is oil seed rape.

Soon ...

Oil seed rape

Inevitably, some of the colonies have already had swarm control applied before the peak of the nectar flow. All of my swarm control this year has been using the nucleus method.

At the first sign of swarm preparation (queen cells, either sealed or charged) I make up a nuc with the old queen, destroy any sealed queen cells and leave one charged cell. I return a week later and knock back all but the one selected cell (which is now sealed). The queen subsequently emerges, mates and starts laying.

This means that several colonies have been queenless throughout the peak nectar flow.

All of these colonies have more and/or heavier supers 🙂 .

Full super ready for extraction

Full super ready for extraction …

The queenless colonies seem to have doubled-down on nectar collection and done particularly well this season.

I’ve noticed this before, but it’s really obvious this spring.

My increasingly foggy memory has a dim recollection of beekeepers in the ‘olden days’ removing queens during the nectar flow precisely because they were more productive. I can’t remember when or where I heard/read/imagined this.

Hold on, not so fast

Are they collecting more or just using less because there is no brood to feed? Remember, 8-9 days after applying swarm control, there will be no larvae to feed as all eggs will have developed into sealed brood.

I could do the maths 15 but there’s a bunch of assumptions to make about the amount of unsealed brood when the queen was removed etc.

Let’s assume for the sake of argument that a queenless colony stores more nectar because the foragers forage more and because there are fewer hungry mouths to feed in the colony.

Perfect … I’ve got a plan for next season.

I’ll preemptively remove the queens 8-9 days before the main flow and buy 20,000 labels and 6 tons of jars in preparation for a bumper honey crop 16.

But, wait a minute … which are the colonies that usually first start swarm preparations?

That’s right … the strongest colonies.

These are the colonies already filling a double brood box, or overflowing a single brood box.

Perhaps they collect more nectar for the simple reason that there are more foragers?

That’s not the impression I have when I compare the performance of what appear to be equally strong colonies with or without queens. However, ’appear’ is a bit of a loose definition and to be sure I’d need to count frames of brood and the number of foragers.

But it’s an interesting thing to think about 17.

Drawing comb

Another thing I noticed is that queenless colonies provided with foundationless frames continued to draw fresh comb. Clearly they don’t need to have eggs or larvae to occupy the new comb to stimulate comb building.

But the vast majority of the comb drawn was drone comb.

Drone-worker-drone

Drone-worker-drone … this frame drawn in a queenright colony

Which, in a roundabout way, led me to this interesting paper:

Smith, M.L. (2018), Queenless honey bees build infrastructure for direct reproduction until their new queen proves her worth. Evolution, 72: 2810-2817.

Michael Smith dequeened colonies and investigated whether they built drone or worker comb. The colonies were provided with frames but no foundation (which would otherwise determine the type of comb drawn).

Comb building in queenless and queenright colonies.

His dequeened colonies built less comb than those with laying queens (A, above), but over 80% of the comb they did build was drone comb (D, above).

Furthermore, they built drone comb even if the colony already contained 25% drawn drone comb (an amount that usually inhibits further drone comb production in a queenright colony).

Finally, he demonstrated that drawing new drone comb only stopped when the colonies contained a new laying queen.

The terminal investment hypothesis

Why should a colony that was queenless or that contained a virgin queen (or for that matter a mated but not laying queen) produce drone comb?

The argument goes something like this.

A colony that is hopelessly queenless can only pass its genes to subsequent generations if it produces laying workers – which lay unfertilised eggs – which consequently develop into drones that mate with virgin queens from other colonies.

The terminal investment hypothesis predicts that the reproductive investment of an individual will change depending upon their reproductive prospects.

Essentially – until there is a laying queen present – the workers pessimistically invest in (i.e. build) drone comb as it offers the only chance of reproductive success should the queen fail to start laying.

Once the queen starts laying they start drawing worker comb again.

As Michael Smith neatly puts it ’When faced with reproductive uncertainty, honey bees may “hope” for the best, but they prepare for the worst’.

And what are the chances of ‘the worst’ happening?

’The worst’ being the failure to replace the queen.

Conveniently Michael Smith also measured the probabilities of successful completion of each of the stages in rearing a replacement queen.

Schematic of the process of rearing a replacement queen, with probabilities of each outcome.

In his studies 98% of queens emerged from the capped cell 18, 95% of virgins returned from mating flights and 95% of those returnees were successfully mated.

0.98 x 0.95 x 0.95 = 0.88 i.e. a queenless colony has an 88% chance of successfully requeening itself, assuming it has eggs/larvae suitable for rearing a new queen.

And the relevance of any of this to practical beekeeping?

  1. Have confidence during swarm control that the bees will predominantly rear good quality queens (so it doesn’t matter which you choose to keep), if …
  2. they are good quality bees. And if they’re not then provide them with eggs/larvae from a better colony. You can easily remove deleterious traits and promote good ones. And, if you’ve not got enough (or good enough) colonies to choose from either a) get more 😉 , or b) ’phone a friend’ and scrounge some suitable eggs/larvae.
  3. Monitor nectar collection by queenright and queenless colonies. Is it different? Many novice beekeepers fret when their colonies are queenless. Maybe at certain times there are benefits 🙂 .
  4. If you want worker comb, don’t provide queenless colonies with foundationless frames.
  5. You should assume ~90% of your virgin queens (0.95 x 0.95) will mate successfully and start laying. Always graft a few more larvae than you actually need.

 

The bees know best

Synopsis : Queens reared under the emergency response are numerous and preferentially started from eggs. The cells are then subjected to strong selection by workers after capping. What does this tell us about good quality queens and can we use this knowledge to improve our own queen rearing?

Introduction

In Eats, sleeps, bees I made a passing comment on the confidence I have in the ability of bees to choose ‘good’ larvae when rearing a new queen. I was justifying why I only leave a single queen cell in a colony that needs requeening. The precise words were:

“I also had total confidence that the bees had selected a suitable larva to raise as a queen in the first place. After all, the survival of the resulting colony depends on it.”

I thought this might be an interesting topic to look at in a little more detail. There is some interesting science on queen cell production.

And subsequent destruction.

Queen cells

Queen cells … have they chosen well?

In addition, there are related observations on what the bees choose as the starting material for queen cells. This should inform our own queen rearing activities. I’ll discuss these (briefly) after presenting the science.

Emergency, supersedure and swarm responses

But first I need introduce the three ‘responses’ under which a colony rears one or more new queens. These are the emergency, supersedure and swarming responses 1

The swarming response

Around this time of the season 2 many beekeepers will be familiar with queen cells produced under the impulse to swarm.

A strong, queenright colony runs out of space. Eggs are laid in specially created vertically oriented cells and are subsequently reared as new queens.

Once these swarm cells are sealed the colony swarms. The old queen and a significant proportion of the workers disappear over the fence. One or more new queens emerge and the colony may produce casts, each headed by a virgin queen. One new queen finally remains, gets mated and heads the original colony.

Swarming is honey bee reproduction … it is the only (natural) way one colony becomes two.

The supersedure response

Supersedure is the in situ replacement of the current queen. The colony produces a small number of supersedure cells – often just one, located in the middle of a central frame 3 – the new queen emerges, mates and starts laying. There may be two queens in the box for an extended period, but eventually the old queen disappears.

Supersedure is probably more common than most beekeepers think. It is the usual explanation for the presence of an unmarked queen at an early season inspection in a hive that had previously contained a marked queen.

The emergency response

If the incumbent queen is removed or killed the colony must rear another or they are doomed. They do this under the emergency response.

Some beekeepers – particularly beginners 4 – inadvertently crush the queen while returning brood frames. They are then surprised at the next inspection to find no eggs but a lot of queen cells.

What’s this? Swarming finished weeks ago!

This is the emergency response at work. The bees select several suitable eggs or larvae, reshape the comb to allow a vertically-oriented cell to be drawn and feed with copious amounts of Royal Jelly.

And voilà, a new queen 5 is produced.

Inducing these responses

The emergency response is triggered by the removal of the old queen – either by physically taking her out of the box, or killing her. Both are easy to achieve 🙁 6

There are ways to induce a supersedure response, but they sometimes involve damaging the queen 7 and are unreliable and – more importantly – ethically dubious. There are more ethically acceptable alternatives.

Lots of beekeepers inadvertently induce the swarming response by not providing the bees with sufficient space, not supering early enough or allowing the brood nest to be backfilled with nectar.

However, doing this in a controlled manner is not a certainty. In one of my apiaries 50% of the colonies have shown no inclination to swarm this season whereas the others all produced swarm cells. All were treated similarly and were – to all intents and purposes – of equivalent strength.

Sealed queen cells produced under the swarming response

For scientific purposes inducing a swarming response cannot be relied upon for studies of queen cell production and selection.

In contrast, the emergency response is 100% reliable. Therefore, in the majority of studies on brood choice, queen cell production and selection, it’s the emergency response that is exploited. That’s certainly the case with the two papers I’m going to briefly discuss this week. 8.

Pick a larva, any larva

Is that what the bees do?

Of course not.

Regular readers will remember from Timing is everything that only larva up to three days old are suitable for producing new queens i.e. six days after the egg is laid.

However, if the queen is laying 1000 eggs per day 9 that still means there are up to 3000 suitably aged larvae in the hive for the production of a new queen, should one be needed.

Eggs and young larvae

Eggs and young larvae

Actually there’s even more choice as the bees can start the queen rearing process – the production of a queen cell – from a cell occupied by an egg … something that has been known for decades, but is relatively rarely discussed.

So, what do they choose?

The first study I’m going to discuss addresses this point and the interesting (and critical) aspect of the quality of the resulting queens that are produced.

Hatch, S., Tarpy, D. & Fletcher, D. Worker regulation of emergency queen rearing in honey bee colonies and the resultant variation in queen quality. Insectes soc. 46, 372–377 (1999).

The study was very straightforward. They induced the emergency response by dequeening strong hives. They then monitored the production and position of queen cells over time, determining the age of the egg/larvae selected by extrapolating back from the day the queen cell was sealed.

Cells that were capped were caged with queen excluder and the resulting emerged queen was analysed to determine her quality. This essentially involved determining her size and weight (the bigger the better) and ovarial number, but they measured additional features as well.

Emergency cell production

In the 8 colonies used, almost all queen cell construction was started within 24 hours of queen removal. A few more cells were produced for up to 48 hours after dequeening, but none were started after that.

There will still be many hundreds of (apparently) suitably aged larvae in the colony at this point. However, these were not selected as all the queen cells that would be made had already been started.

Colonies produced different numbers of queen cells, from 6 to 56 (average 27).

However, the majority of these cells were torn down before emergence, and a few of those that were sealed never emerged. Of the 217 cells started, 115 (53%) were torn down, 11 (5%) did not emerge and the remaining 91 (43%) emerged.

Not only did the number of queen cells produced vary greatly between hives, so did the numbers of queens that emerged – from 3 to 20 (average 11).

The brood nest is roughly spherical or rugby ball-shaped and usually occupies the centre of the hive. About 46% of the cells started were on the central three frames, and these had a much greater chance of producing queens. This was because queen cells started on the central frames of the brood nest were less likely to be torn down (41%) than those on the periphery (71%).

Pick an egg or a larva (in which case, the younger the better)

So if it’s not Pick a larva, any larva’, what do the bees choose to start their emergency queen cells from?

Remember how important this is. Without a new queen the colony cannot survive. The clock is ticking. They only have a few days to make this choice before all the brood in the nest are too old for queen production.

The non-random construction of queen cells.

They predominantly choose eggs.

Almost 70% of queen cells started were initiated when the cell contained an egg, rather than a larva. What’s more, the majority of the eggs chosen were three days old.

If you consider that there were 6 possible choices (1, 2 or 3 day old eggs and 1, 2 and 3 day old larvae), it’s striking that 34% of all the queen cells produced were from 3 day old eggs.

In fact, it turns out that only five choices were made as none of the queen cells were started from 3 day old larvae.

Furthermore, over 60% of queen cells produced from 2 day old larvae were subsequently torn down.

Bees choose to make queens from the oldest eggs or the very youngest larvae.

Are you getting the message?

Since the production of a new queen is essential for colony survival we should assume that the bees have evolved a queen cell production ‘strategy’ that maximises the chances of producing a suitable queen.

Almost 60% of the ‘starting material’ chosen by the bees to ensure colony survival – that resulted in queen production – were 3 day old eggs or 1 day old larvae.

This emphasises the need to provide colonies we use for queen rearing with eggs and larvae of this age range. It also reinforces the importance of only selecting the smallest larvae possible when grafting.

The choice the bees make is presumably because queens reared from older larvae are of poorer quality, perhaps because they have a reduced period for feeding with Royal Jelly.

So how do the queens produced from eggs and young larvae compare?

Queen ‘quality’

Of the 91 queens that emerged only 89 were analysed because two ”escaped capture”.

It’s reassuring to know that it’s not just cackhanded beekeepers that make mistakes 😉

There were no differences in the morphology – weight or size – for queens that emerged from cells on either the central or peripheral frames 10.

However, queens reared from 3 day old eggs were significantly heavier than queens reared from larvae. In addition, queens reared from 3 day old eggs had a longer thorax than queens reared from either younger eggs or larvae.

Other morphological measurement – e.g. wing length or width – did not differ significantly between queens reared from eggs or larvae.

But are these hefty, long-thoraxed, queens better quality?

This isn’t a simple question. What does better quality mean? It’s not the size or productivity of the resulting colony she heads since that is also influenced by the genetics and number of drones she mates with.

It’s also time consuming and impractical to measure scientifically (for 89 queens).

Instead, the scientists measured the number of ovarioles and the volume of the spermatheca as potential indicators of fecundity. There was no relationship between weight and ovariole number, irrespective of the age of the egg or larva when the cell was started.

If not more fecund, what?

So, if bigger queens don’t necessarily have increased fecundity (though remember, this wasn’t shown – all they demonstrated was that the ‘innards’ involved in fertilised egg production were similar) why might the bees select eggs/larvae that resulted in bigger queens being produced?

One possibility is that these bigger queens have greater success in what is termed polygyny reduction.

This is what beekeepers call fighting.

If more than one queen is present they fight until only one is left in the hive. This hadn’t been extensively studied in 1999 (when this paper was published) but has been addressed in other studies 11.

Alternatively, and suggested in a tempting but cryptic ’unpublished data’, heavier queens may be able to achieve higher levels of polyandry i.e. mate with more drones, so increasing the genetic diversity, and consequently the fitness, of the colony. I’ve discussed the importance of polyandry and so-called hyperpolyandry for colony fitness and disease resistance previously, so won’t revisit these here.

It’s easy to speculate that a queen with a larger thorax may have better developed flight muscles. These might enable her to stay longer in drone congregation areas for mating.

Why are so many cells started (and queens reared)?

In the emergency response only one queen is needed to ‘rescue’ the colony from oblivion.

Why therefore are so many queen cells – on average 27 per colony – started?

And why do the workers allow an average of 11 queens emerge?

The authors suggest a number of possible reasons:

  1. Colonies raise multiple queens to guarantee the requeening process. This assumes that the ‘cost’ of queen rearing is low, which seems reasonable. Since only 5% of queens raised failed to emerge it is probably not to overcome this limitation.
  2. Multiple queens allow colony reproduction if conditions are suitable. Only colonies that raise multiple queens would be able to (simultaneously) reproduce and requeen, so there might be a selective pressure to allow this.
  3. A consequence of age demographics (brood or workers) in the colony. This is slightly trickier to explain and has not been tested. Queen cells result from an ‘interaction’ of available brood (eggs/larvae) with workers. A colony has variable numbers of both, and there are a variety of worker cohorts, only some of which contribute to cell building. Therefore, the production of multiple cells (and queens) may simply reflect the variation in the factors – ages of brood and workers – involved.
  4. Rearing multiple queens allows workers to select the ‘best’. That’s clearly wrong because the ‘best’ would be just one queen. Perhaps a better explanation would be that it allows workers to either select for better queens by destroying those that are less good.

No single reason

Biology is complicated 12 and it may be that all four of the reasons above are correct. There may be (and almost certainly are) additional reasons that favour the production of multiple queens.

However, of the four reasons above, this paper provides nearly compelling evidence that the workers are selecting which emerge and which do not.

Remember, 53% of the cells that were started were torn down.

In addition, there was both a spatial and temporal bias to the cells that were torn down. This strongly suggests that the process (of cell destruction) was not random.

However, it remains only nearly compelling because we know nothing about the queens that were in cells that were torn down.

By definition those queens don’t exist. The cells were torn down and the queens killed/eaten/discarded so we have no measure of their quality.

If they were indistinguishable from those that did emerge then I’d struggle to convince you that the worker selection was producing ‘better queens’ from the large number of queen cells that were started.

Analysing the non-existent

But fortunately this experiment has been done.

Tarpy, D.R., Simone-Finstrom, M. & Linksvayer, T.A. Honey bee colonies regulate queen reproductive traits by controlling which queens survive to adulthood. Insect. Soc. 63, 169–174 (2016).

The experimental methods were almost identical. However, this time, when they caged the capped queen cells they randomly assigned them to cages that either allowed or prevented worker access (both types of cages prevented the escape of the queen).

They then analysed the queens that emerged from the ‘worker-accessible’ and ‘worker-excluded’ queen cells.

The hypothesis was straightforward, if the workers were randomly destroying a proportion of queen cells there would be no differences in the characteristics of the resulting queens. Conversely, if there was selection, the queens from the ‘worker-excluded’ cells would be different.

The overall numbers of queen cells produced (average 12, range 4 – 22 per colony) and the proportion – 57% – of the ‘worker-accessible’ cells torn down were similar to the study I’ve already described.

Effect of queen treatment on two different measures of queen reproductive potential.

‘Worker-excluded’ queens were significantly smaller than those from ‘worker-accessible’ cages. They also weighed less. This is obvious from the top left panel (above) but confounded 13 by the small size of the study and the significant differences in the weight of queens produced in different colonies 14.

Despite the limited size of this study these results strongly suggest that workers are somehow ‘weeding out’ lower quality (defined here as smaller and probably lighter) queens.

I’ll leave it to you to speculate on how the workers outside the queen cell determine the size/weight/quality of the queen inside the cell … 😉

Does this have relevance to beekeeping?

I think there are a number of interesting points from this study that have relevance to practical beekeeping.

  • Queen cells were started under the emergency response only in the first 3 days after the queen was removed. The vast majority were started within 24 hours. This should help determine when the queen went missing or – if you deliberately removed her – defines the latest date that you need to be concerned about new cells being started.
  • If you are improving your stocks by adding larvae from a separate colony 15 then make sure you add a frame containing eggs and larvae. You want to be sure they have access to 3 day old eggs.
  • It probably makes sense to place this frame in the centre of the brood nest.
  • If you’re grafting larvae for queen rearing – as I’ve already suggested – make sure you choose those under ~18 hours old. The younger and the smaller the better.
  • But, perhaps we should instead think about grafting eggs rather than larvae?

This last suggestion is a topic of a (part-written) future post.

Here are a couple of additional points to think about. Studies have shown that egg transfer results in the largest queens. However, eggs are accepted significantly less well than larvae … and some colonies will not accept them at all. I’ll discuss this in more detail some other time.

And a final caveat …

The final point to remember is that both these studies analysed queen cell production and the resulting queens under the emergency response.

Many queen rearing methods – the so-called ‘queenright’ ones such as my favoured Ben Harden method – exploit the supersedure response. It’s always possible that the bees have different preferences for queens reared under the supersedure (or for that matter the swarming) responses.

But I doubt it 😉

After all … colony survival is dependent upon good quality queens and the bees know best.


 

Eats, sleeps, bees

Synopsis : The beekeeping season is starting to get busy. Swarm control is not only essential to keep your hives productive, but also offers easy opportunities to improve the quality of your bees. Good records and a choice of bees is all you need. This week I discuss stock improvement together with a few semi-random thoughts on honey labelling, colony behaviour and wax foundation. Something for everyone. Perhaps.

Introduction

May is usually a lovely month in Scotland. It is often dry and sunny enough to spend much of the time outdoors, the days are long enough 1 to get a lot done and it’s early enough in the year to avoid the dreaded midges 2.

Usually and often.

Unfortunately, the weather so far this month has been unseasonably cool. It was probably better for much of March than it’s been for the first half of May.

But that good weather in March gave the bees a real boost – particularly in my apiaries on the east coast of Scotland.

Consequently, there’s still a lot of beekeeping to do now – swarm control, preparations for queen rearing, catching up with all the things I didn’t do in the winter ( 🙁 ) – often in between some rather iffy weather 3.

The next couple of months are usually pretty much full on … hence Eats, sleeps, bees 4.

Latitude …

The differences I discussed in Latitude and longitude a month ago are particularly marked now.

Beekeepers in Sussex or Kent have been complaining about running out of supers since mid-April. Other have been proudly displaying their first (or second) round of grafted queen cells.

In contrast, a few of my west coast colonies are still only on 6-7 frames of brood. It will be at least another fortnight until I even think about whether they’ll need swarm control.

Which might be a fortnight before they’ll actually need it.

These are perfectly healthy west coast native bees, adapted to the climate and forage available here.

The wonderful west coast of Scotland

They are classic late developers, evolution having timed colony expansion to fit with the local forage and the availability of weather good enough for queen mating.

There’s insufficient forage to produce oodles of brood in late April and many colonies have yet to produce any mature drones (though they all now have drone brood). Instead, they build up rather slowly, and are probably at the peak in July when the heather starts to yield.

This is all reasonably new to me and I feel I’m still learning how the season develops here on the west coast. I’m sure I’ll get the hang of it.

Eventually 😉

Going by the rate colonies are currently building up, and their performance last year, I expect to be rearing queens from these colonies in June and early July 5.

… and longitude

Meanwhile, in Fife things are progressing much faster.

My apiaries there are about 160 miles east and at a similar latitude, but most of the colonies are already overflowing their boxes. Swarm prevention is a distant memory and I’m now busy with swarm control.

The genetics are different. My east coast bees are all local mongrels, again adapted to local conditions.

However, I suspect an even greater difference is the early season forage and – although it’ll be finished in the next week or so – the oil seed rape (OSR).

Oil seed rape … and rain

The OSR gives colonies a massive boost. They gorge on it – both the nectar and pollen – quickly filling supers and a multitude of hungry larval mouths. Reasonably strong nucs made up for swarm control on the 1st of May are now in a full brood box and will be more than ready for the summer nectar flow when it starts.

Queen rearing would have started already if the two boxes I’d earmarked for cell raising hadn’t become a little overcooked and produced queen cells at the beginning of the month 🙁 .

The best laid plans etc. 6.

And, to add insult to injury, the (lovely quality) colony I’d intended to source larvae from produced queen cells the following week.

D’oh!

Quality control

One of the (nominal) cell raising colonies – we’ll call it colony #6 for convenience 7 was borderline in terms of temperament.

On a balmy afternoon, with a good nectar flow, the bees were calm, unflustered and a pleasure to handle.

However in cool, damp or blustery weather they weren’t so great.

This is one of the reasons that record keeping is so important. Although I’d not inspected them this season in very poor conditions 8, my records from last year also showed they were, shall we say, ’suboptimal’. Not psychotic or even hugely aggressive, but certainly hotter than I’d prefer and nothing like as stable on the comb as I like 9.

Of course, the simple answer is not to go burrowing through the box in cool, damp or blustery weather’ 🙂

However, I don’t always have a choice as these bees are 160 miles away. Met Office forecasts are good for tomorrow, questionable for next week and essentially guesswork for next month (which is when I’m booking the hotels).

So, having realised that both swarm control and quality control were needed, how have I tried to improve the quality of this colony?

Controlling quality

I discovered open, charged queen cells in colony #6 on the 1st of May. Without intervention the colony would have swarmed before the end of the first week of the month 10. The queen was clipped but, as I hope I made clear last week, queen clipping does not stop swarming.

Swarm control

I used my preferred swarm control method by making up a nuc with the old queen and a couple of frames of emerging brood with the adhering bees. I put these, together with a frame of stores and a couple of new frames into a nuc box and moved them to an out apiary several miles away.

By moving the nuc away I don’t have to worry about losing bees back to the original hive. I can therefore make the nuc up a little weaker than I would otherwise need to. An out apiary (or two) isn’t essential, but it makes some tasks a lot easier.

I then went carefully through colony #6, shaking all the bees off each frame and destroying every queen cell. There were still eggs and young larvae present, so they would undoubtedly make more queen cells before my visit a week later. However, by shaking every frame and being rigorous about destroying every queen cell I ensured:

  • there would be a bit less work to do the following week
  • I’d not missed a more mature cell somewhere that could have left a virgin queen running about at my next visit. This was unlikely, based upon the timing of brood development, but it’s better to be safe than sorry.

Colony #6 is in a double brood box. While ransacking the brood nest for queen cells I also hoiked out a frame of drone brood and cut out yet more drone brood from a foundationless frame or two. Since the genetics of this colony was questionable it made sense to try and stop these undesirable genes being spread far and wide.

At the same time I rearranged the frames, moving all the unsealed brood into the top box.

One week later

Early on the morning of the 8th of May I checked the colony again. As expected there were more queen cells reared from eggs and larvae I’d left the week before.

The vast majority of these queen cells were in the top box, but – since I’m a belt and braces beekeeper – I checked the bottom box as well. Again, it’s better to be safe than sorry.

All of the queen cells were again destroyed.

Tough love … but if you want to improve the quality of your bees you have to exclude those with undesirable characteristics.

Importantly, by now the youngest larvae in the colony would be at least four days old. This is really too old – at least given the choice (and I was going to give them a choice) – to rear a new queen from.

Room for one more …

I rearranged the frames, leaving a gap in the middle of the top box, closed colony #6 up and completed my inspection of the other colonies in the apiary.

The last colony I checked was my chosen ‘donor’ colony with desirable genetics.

More swarm control 🙂 and a few days saved

The donor colony (#7) had started queen cells sometime during the first week of May and so also needed swarm control. However, very conveniently it had produced two nice looking cells on separate frames.

Both these queen cells were 3-4 days old and so would be capped in the next 24-48 hours.

A three and a bit day old queen cell

I could therefore use my standard nucleus swarm control (to ‘save’ the queen ‘just in case’), leaving one queen cell in colony #7 and donating the other queen cell to colony #6.

Which is exactly what I did.

Having gently brushed off the adhering bees from the frame (you should never vigorously shake a frame containing a queen cell you want 11 ) I gently slotted it into the gap I’d left in the upper brood box of colony #6. I also marked the frame to make my subsequent check (on the 15th) easier.

The frame marked QC is the only one that needs to be checked next week

By adding a well developed, but unsealed, queen cell to colony #6 I’ve saved the few days they would have taken to rear a queen from an egg or a day old larva.

Because the cell was open I was certain it was ‘charged’ i.e. it contained a fat larva sitting contentedly in a deep bed of Royal Jelly 12.

Better to be safe than sorry (again)

There were also eggs and a few larvae on the frame containing the queen cell (which was otherwise largely filled with sealed brood). It was likely that some of these would also be selected to rear new queens.

And they were when I checked on the 15th.

There was my chosen – and now nicely sculpted and sealed – cell and a few less well developed cells on the donated frame.

I know the cell I selected was charged and the larva well nourished.

In addition, I also had total confidence that the bees had selected a suitable larva to raise as a queen in the first place. After all, the survival of the resulting colony depends on it.

Therefore, I didn’t need any backups.

No ’just in case’ cells.

Rather than risking multiple queens emerging and fighting, or the strong colony throwing casts, I (again) destroyed all but the cell I had originally selected.

I’m writing this on the 17th and she should have emerged today … so my records carry a note to check for a laying queen during my first inspection in June.

This shows how simple and easy stock improvement can be.

No grafting, no Nicot cages, no mini-nucs and almost no colony manipulations etc. Instead, just an appreciation of the timings and the availability of a frame from a good colony (and this could be from a friend who has lovely bees … ).

And in between all that

That was about 1400 words on requeening one colony 🙁 . That was not quite what I intended when I sat down to write a post entitled Eats, sleeps, bees.

My east coast beekeeping – including 8-9 hours driving – takes a couple of days a week at this time of the season. On the west coast I have fewer colonies and – as outlined above – they are less well advanced, so there’s a bit less to do 13.

However, there are always additional bee-related activities that appear to fill in the gaps between active colony inspections.

I’ll end this post with a few random and half thought out comments or questions on stuff that’s been entertaining or infuriating me in the last week or so.

In between the writing, inspections, Teams meetings, editing, reviewing and writing … 😉

Honey labelling

I use a simple black and white thermal printer – a Dymo LabelWriter 450 – to produce labels that don’t detract from (or obscure) the jar contents.

Dymo thermal label (and a jar of honey)

I’ve used these for over 6 years and been very happy with the:

  • cost of the labels (a few pence per jar)
  • flexibility of the system. I can change the best before date, the batch number or other details for each print run; whether it’s 1 or 1000.
  • ability to include QR codes containing embedded information, like a website address or details of the particular batch of honey.

However Dymo, in their never ending quest for more profits a ‘better consumer experience’ have recently upgraded their printers and label printing software 14.

The newest incarnation of the printer I use – now the Dymo LabelWriter 550 – only works with authentic Dymo labels.

A more accurate spelling of authentic is  e x p e n s i v e , at least if you only buy labels in small quantities (100’s, not 1000’s).

If you fancied adding a little square label on the cap of 100 jars claiming ”Delicious RAW honey” you’d not only be falling foul of the Honey Labelling Regulation, you’d also have to cough up £18 for a roll of labels.

Dymo labels are great quality. Smudge proof, easy to remove and sharp black on white. In bulk they are reasonably priced (~3p – the same cost as an anti-tamper label – if you buy >3000 at a time).

However, you can get similar labels for a third of the price … but they won’t be usable in the new printer.

The Dymo LabelWriter 450 has no such restrictions and is still available if you look around.

I’m tempted to buy a spare.

Colony to colony variation

I started this post with a discussion of variation due to latitude and longitude. However, individual colonies in a single location can also show variation (in addition to temperament, running, following etc.) that I don’t really understand.

I have three colonies in a row behind the house here on the west coast. I can see whether they are busy or not when I’m making coffee, doing the washing up or pottering in the work room (two of these activities are more common than the other 😉 ).

All in a row (though not the colonies referred to in the text as they’re camera shy)

And they are consistently different, despite being pretty similar in terms of colony strength and development.

One colony typically starts foraging before the others and another, probably the weakest of the three, forages later and in worse weather.

Early in the season these differences were so marked I thought that one of the colonies had died.

I assume – because a) I’ve not got the imagination to think of other reasons, b) it’s the justification I use for anything I don’t properly comprehend, and c) I’ve not done any experiments to actually test what else it could be – that this is due to genetics.

It’s only because I’m fortunate enough to look out on these colonies dozens of times a day that I’ve noticed these consistent behavioural differences. I suspect my other colonies show it, but that I’ve never looked carefully or frequently enough.

Attractive foundation

I’m busy making up nucs for swarm control and sale. Although many of the frames I use are foundationless I also use a lot with standard foundation. The frames are built (or should be built!) in the winter, but I add the foundation once the weather improves and there’s less risk of cracking the brittle sheets due to low temperatures.

I buy foundation once every season or so and carefully store it somewhere cool and flat. Some of these sheets are quite old by the time I get round to using them and they often develop a white powdery ‘bloom’ on their surface.

Before (bottom) and after (top) 30 minutes in the honey warming cabinet

I used to run a hairdryer over the frames containing these bloomed sheets. The warm air brings out the oils in the wax and makes they much more attractive to the bees. They smell great!

Frames in the honey warming cabinet (W = worker foundation, to distinguish them from D = drone)

These days I just stick a ‘box full’ of frames at a time into my honey warming cabinet set at about 40°C for 30 minutes. Not necessarily quicker, but a whole lot easier … so freeing up time to do something else related to bees 🙂


Note

Today is World Bee Day. The 20th of May was Anton Janša’s (1734-1773) birthday. He was a beekeeper – teaching beekeeping in the Hapsburg court in Vienna –  and painter from Carniola (now Slovenia). He promoted migratory beekeeping, painted his hives and invented a stackable hive. 

Timing is everything

Synopsis : The invariant timings of brood development dictate many beekeeping events including colony inspections, queen rearing and Varroa management. It makes sense to understand and exploit these timings, rather than ignore or fight against them.

Introduction

There are some inherent contradictions involving timing in beekeeping that can confuse beginners. Actually, they can confuse anyone – beginner or old lag 1 – who doesn’t appreciate the considerable flexibility of some of the timings and the near-total inflexibility of others.

I think that many of the inherent difficulties in beekeeping e.g. judging when to do what to the colony, comparing seasonal differences or deciding whether intervention is needed or ill advised, are due to a lack of appreciation of the relative importance of some of these timings.

I gave an overview of some of the ‘flexible timings’ a couple of weeks ago when discussing the year to year climatic variation that compounds differences caused by latitude.

The onset of brood rearing in midwinter, the crossover date 2, the start of swarming and the timings of the major and minor nectar flows can all vary from year to year.

To appreciate these you need to be observant, but predicting their impact can be tricky. Some are multi-factorial e.g. colony strength and development in a warm, dry spring can be different to a warm, wet spring.

I’ve probably written enough about some of these flexible events already so will instead focus on some of the ‘inflexible timings’ that dictate the activity of the colony and, by extension and through necessity, the activity of the beekeeper.

In many ways these are easier to understand.

By definition, they are invariable 3.

Less to remember … but remembering them is important 😉

The environment

Those ‘flexible timings’ I refer to above mainly reflect the year-to-year climatic variation – warm springs, Indian summers, hard winters.

In contrast, inside the hive the environment is remarkably stable.

It can vary from 4°C to 40°C outside – even on a single day – but the temperature in the brood nest is controlled within a narrow 33-36°C range.

Hives in the snow

Freezing outside, 34.5°C in the broodnest

In fact, in the very centre of the brood nest – the region where pupal development takes place – it is as near as makes no difference 34.5°C.

The workers thermoregulate the hive, heating the comb where needed 4 or evaporating water to cool the hive.

With hive monitoring equipment and suitably placed thermometers you can tell when a colony shifts into brood rearing mode in the spring – the varying temperature of the clustered bees increases and stabilises to a near-invariant 34 and a bit degrees Centigrade.

Brood rearing starts ...

Brood rearing starts – indicated by stabilisation of brood temperature (arnia.co.uk)

The image above is from Arnia who make hive monitoring equipment. The key phrase in the sentence above is ‘suitably placed thermometers’. You tend to have only one or two and they can’t be everywhere, so it’s easy to miss the onset of brood rearing.

Temperature, behaviour and neuroanatomy

Stable temperatures are important for brood development. Worker bees reared at 32°C are less good at waggle dance communication. They only complete about 20% of the circuits (less enthusiastic) and exhibit more variability in the duration of the waggle phase (the distance component) when compared to bees reared at higher temperatures within the ‘normal’ range 5.

In further studies, bees reared at abnormally low or high temperatures (though varying by only 1-2 °C from normal hive temperatures) exhibited differences in neuroanatomical development 6. Of the regions of the brain studied, the numbers of microglomeruli within the mushroom bodies of the brain, areas involved in memory and learning, differed significantly when the pupation temperature was as little as 1°C over or under 34.5°C.

Despite these behavioural and developmental differences, the emergence rate and the duration 7 of development are somewhat less influenced by brood nest temperature.

Influence of temperature on pupal brood development – duration (left axis) and emergence rate (right axis)

In the graph above the duration of pupal development is 10-11 days between 34.5°C and 37°C, and eclosion (emergence) rates exceed 90% from 31-36°C.

Correct development of honey bee workers therefore requires a stable brood nest temperature.

As a consequence of this stability the duration of the development cycle is highly reproducible and – more to the point – predictable.

Before discussing the development cycle it’s worth noting that queens and drones are reared under similarly stable conditions. I’ve discussed the influence of temperature on queen development before but am unaware of similar studies on drones.

The development of workers

The graph above shows the influence of temperature on the duration of pupal development. This is not the same as sealed brood development. 8. The 10-11 days shown above needs to be extended by 2 days (48 hours) when considering the more beekeeper-friendly concept of sealed or capped brood.

Under normal conditions worker development takes 21 days. Three days as an egg, five as an open larva and 13 capped 9.

During those 21 days bees go through a series of six molts between five developmental stages termed instars. The first molt is the egg hatching, molts 2-4 occur during the first few days of larval feeding. Molt 5 is the change from the pre-pupal capped larva to the pupa and the final molt occurs at emergence.

Once the brood is capped there’s nothing much the beekeeper needs to worry about (or can do). In contrast, the early days of worker development involve at least one notable event 10.

Young larvae and queen rearing

The worker larva is fed progressively, which essentially means almost all the time. Nurse bees visit the larva thousands of times, initially feeding a mix of secretions from the hypopharyngeal and mandibular glands. The diet is then switched to one lacking the mandibular gland component and is finally supplemented with pollen and honey.

This dietary switch takes place around day three of larval development and effectively seals the fate of the developing bee as a worker.

Before day three of larval development, larvae destined to be workers or queens receive the same diet. After day 3 a series of genetic switches are ‘pushed’ that prevent the larva developing into a queen.

This means that larvae of less than three days old are needed to produce new queens. A terminally queenless colony will sometimes attempt to rear a new queen from an older larva (if nothing else is available) but these are usually substandard – so called scrub queens – or fail.

The adult worker

After emergence the worker fulfils a number of roles for the colony; nurse bee, comb builder, guard, scout, forager etc. The precise timings of these are flexible. Not all bees of the same age have the same role, and they can even be reversed. However, as far as practical beekeeping is concerned 11, the only other timings that really matter are the longevity of workers; in the summer this is about 6 weeks and in the winter, 6 months.

The timings to remember – workers

The full development cycle takes 21 days. Larvae more than 3 days old 12 are unsuitable for queen rearing (and, as I shall discuss in a future post, better queens are produced from younger larvae). The adult worker spends the first half of her 6 week life within the hive, and the last 3 weeks as a forager. Winter bees live for many months.

The development of queens

The development cycle of the queen bee is shorter than that of the worker because their diet is much richer. Of course it’s not quite that straightforward (it wouldn’t be, would it?). Because of the diet there are a number of genetic pathways turned on or off in the developing queen that ensure she is ‘fit for purpose’ on emergence. The developing queen goes through the same number of molts and instars, but they are compressed in time.

Sealed queen cell ...

Sealed queen cell

The queen cell is sealed on the ninth day of development, the fifth day after hatching from the egg, and the queen emerges on the 16th day.

The adult queen

Relative to workers and drones the queen appears almost immortal. A queen may live for at least three years and, if well looked after, longer than that. Most of this aftercare is provided by the hive, but the beekeeper can influence things as well. High quality ‘breeder queens’ are often kept in nucs and discouraged from laying excessive amounts of brood. This prolongs their effective lifespan.

As far as timings are concerned – and assuming we’re not dealing with a $500 breeder queen – the only three things that are important relate to the mating of the queen.

After emergence the queen needs to reach sexual maturity before she can go on her mating flights, this takes 5-6 days. Once mated there is a further delay of 2-3 days before the queen starts laying. The final number to remember is that adult queens older than 26-33 days are too old to mate.

The timings to remember – queens

The full development cycle takes 16 days. The cell is capped on the 9th day after the egg was laid 13. Upon emergence, queens take 5-6 days before they are mature enough to mate. A mated queen starts laying 2-3 days after returning from her last mating flight. If they’re not mated within about 4 weeks of emergence then they’ve blown it.

Therefore, the minimum duration to go from newly laid egg to mated, laying queen is at least 23 days. Alternatively, assuming a 2-3 day old larva is available, this time period is reduced to about 18 days.

From emergence, it’s theoretically possible 14 to have a mated, laying queen within 8 days.

However, in my experience, queen mating usually takes longer than these minima … and always longer than I want. Other than confirming emergence I always leave a new queen a minimum of a fortnight before checking if she’s laying, and longer if the weather has been unsuitable for mating.

The development of drones

Like teenage boys getting up late and then doing nothing other than lounge around eating and thinking about sex 15, the drone takes the longest to emerge. The full development cycle from the laying of an unfertilised egg to emergence takes 24 days.

As before, the number of molts and instars are the same as undergone by queens and workers.

The adult drone

Like the queen, the drone needs to become sexually mature before going on a mating flight. This takes 10-12 days after emergence. The drone has a finite lifespan and usually lives no more than about a month during the summer.

Drones that successfully mate with a queen prematurely die. Those that don’t mate either die trying or are ejected from the hive by the workers at the end of the season.

It’s not unusual to hear beekeepers talk about finding drones overwintering. I’m not aware whether these are exceptionally long-lived drones laid by the queen the preceding summer/autumn, or laid by a failing queen during the winter, or even by laying workers in a queenless colony overwinter 16.

The timings to remember – drones

The full development cycle takes 24 days. It takes about five weeks between the appearance of the first eggs in drone cells and the presence of sexually mature drones in the hive.

Swarming cannot happen until there are drones in the area, so it’s worth keeping an eye of drone brood production.

Hive inspections and queen rearing

So, there you have it, just a few numbers to remember … and, more importantly, to understand their significance for beekeeping.

Unusually I’ve prepared an oversized figure to illustrate these timings 17 with colour-coding worker, queen and drone events in green, blue and red respectively.

Worker, drone and queen development and key post-emergence timings

Note that some timings have dual significance. Worker larvae no more than three days old (day 6 – in green) can be reared as queens with suitable feeding.

Hive inspections … and caveats

It should now be obvious why regular weekly hive inspections are recommended in the time leading up to and during the peak swarming period.

If there are no charged queen cells – those containing eggs or developing larvae – during an inspection then any that do develop in the seven days before the next inspection will still not be sealed (and therefore the colony will not have swarmed).

This assumes that the colony swarms on or after the day that the queen cell is sealed.

Sometimes – rarely – the swarm goes early, apparently leaving only uncapped swarm cells. When I’ve had this happen a thorough examination of the brood frames has sometimes turned up a sealed cell, tucked away against a sidebar, that I’d missed in the previous inspection … the colony had not swarmed early, I’d 18 not been observant enough.

With a well-populated colony it’s sometimes necessary to shake all the bees off each frame to be certain there are no queen cells lurking under the ruffled curtain of workers.

Not all queen cells are this obvious

Colonies containing clipped queens tend to delay swarming (but they certainly still swarm) and you can usually get away with a 10 day interval between inspections. Furthermore, since the clipped queen cannot fly, even if the colony does swarm they usually return and end up clustered underneath the OMF after she has crawled back up the leg of the hive stand.

Outside the main swarming period inspections can be much less frequent. I usually inspect only once or twice between mid-July and the end of the season.

Queen rearing

One of my (few) poorly tempered hives unexpectedly contained several 3+ day old queen cells last Sunday. I made up a nuc with the old queen, destroyed all the queen cells and closed up the hive.

They will produce more queen cells 19, but they cannot swarm as there’s no queen.

At my inspection this Sunday I will destroy all the new queen cells.

The genetics of this colony are (at best) ‘undesirable’ 🙁 

Since there’s been no laying queen in the hive for 7 days there cannot now be any larvae young enough to be reared as a new queen 20. Therefore, having destroyed all the queen cells, I’ll add a frame of eggs and larvae from a (well-behaved and so genetically desirable) neighbouring colony 21.

If they want a new queen 22 they will rear one from this donated frame.

The 23 egg in the graphic above is the earliest you can expect a laying queen. In reality – as explained above – it usually takes longer. A minimum of 30 days from egg to egg-producing queen is perhaps more dependable.

Therefore, in around 24 to 30 days – and most likely the latter – this colony will have a new queen which will hopefully improve their behaviour.

The timing of Varroa treatment(s)

But think about what’s happening to the rest of the brood in that colony.

The last eggs laid in the colony was on the Sunday the 1st of May. By the 21st of May all the worker brood will have completed development and emerged. By the 24th of May all the drones will have emerged.

The colony should therefore be broodless in the last week of May.

Even if the new queen is laying by then (some chance!) she won’t have produced any sealed brood.

If needed I could use this 7 day window of opportunity to treat the colony with oxalic acid and reduce the Varroa levels in the hive.

It’s unlikely I’ll need to as the mite numbers have been low this season. However, it’s very reassuring that I have the option should I need it 24.

Adding a Varroa board to check mite drop

But … hang on a moment.

Why did I write that the colony only should be broodless?

What about the eggs and larvae on the frame I added from the donor colony? 25

These will be up to one week younger than any brood in the queenless colony.

Potentially those young eggs and larvae will close that ’window of opportunity’.

Perhaps the easiest way around this is to excise one good sealed queen cell from the donated frame and leave it in queenless colony, and then remove the donated frame and use it elsewhere.

If the colony produces several good quality queen cells it’s likely that I’ll chop them all out and make up some nucs – queen rearing without all the graft.

Literally 😉

Conclusions

I’ve written far more than I intended but I think this reflects the importance of the – effectively invariant – timings of brood development.

These dictate so many of our beekeeping activities that it makes sense to learn to work with them, rather than forever struggling against them.

With good observation and regular colony inspections – weekly during the the main part of the season – there should be little or no chance of losing a swarm.

Furthermore, should a colony show signs of swarm preparation, timely intervention coupled with an appreciation of the timings of brood development, mean you have the opportunity to conduct both stock improvement and mite management.

Nice one 😉


 

The bee bag

Synopsis: Preparing for the season ahead should include making sure you have everything you need in the bee bag for apiary visits, but that you are not carrying things you never use. A place for everything, and everything in its place … at least until swarming starts.

Introduction

I think there’s sometimes a misconception that those who write (or talk) about a topic are the most knowledgeable on that topic.

After all, why else would they feel qualified to write?

And, if they’re knowledgeable – even if not all knowing – then they also have the luxury of time (to write, or to enjoy the scenery or whatever). Rather than repeatedly struggling doing the wrong thing, they briefly and efficiently do the right thing™.

Their incisive and unwavering decision making, coupled with a calm and measured confidence, means difficult tasks are made easier and routine activities are rendered trivial.

And this efficiency of thought and activity is complemented by an impressive level of organisation and preparedness. After all, how else would they be able to achieve what they do, without being prepared for all eventualities … and have the tools immediately to hand that are needed?

I’m sure that’s true of some who write … and it might even be true of some who write and talk about beekeeping … but it’s not true of me 🙁

At least, not often.

I might write about how I did something, making it sound trivial and unexciting:

“… pick the queen up by her wings and place her in the JzBz cage, add a few nurse bees to keep her company and place the cage safely in your pocket.”

But I omitted to describe the times I couldn’t find a JzBz cage, or got stung repeatedly grabbing workers, or let the virgin queen fly around the shed for 5 minutes before she disappeared out of the door.

Or when the cage fell through the hole in my pocket (caused by a razor sharp hive tool), down my trouser leg and into my boot.

Those who can, do; those who can’t, teach

The luxury of writing means I can skip over those things that make me sound like the author of the bestselling Slapstick beekeeping, and instead present a coherent vision of what beekeeping should be like.

Think of it as a sort of sanitised version of beekeeping, with the swearing bowdlerised and the Charlie Chaplin-style antics omitted to make me look vaguely competent.

Not, I should add, that every visit to the apiary looks like Laurel and Hardy 1 in beesuits.

I do my best to learn from my mistakes, or at least not forget them, and – every winter – I incrementally improve my organisation for the season ahead.

I review my notes from the season just finished and I make general, and sometimes very specific, plans for the following year. If these necessitate buying or building new equipment then I try and do that during the seemingly interminable short winter days (if that isn’t oxymoronic).

This winter this has involved completing my queen rearing incubator and building some cell punches for queen rearing.

Cell punches

The organisation involves preparing this new ‘stuff’ as well as sorting out some of the accumulated debris from the season just finished.

End of season squalor – yes, that is a small bag of fondant buried in the bee bag

In particular, I sort through, tidy and hopefully streamline, the contents of the bee bag.

The beekeepers box

When you visit the apiary there are a few tools you will almost always need – for example, a smoker and a hive tool. You’ll need something combustible in the smoker and some way of igniting it. And you should have something to carry that lot in that is itself non-flammable, so you don’t risk self-immolation when driving back home.

I’ve discussed the fireproof box I use for my smoker previously. I now keep smoker fuel and a kitchen ‘creme brûlée’ blowtorch in a clear plastic box. Bitter experience – you can guess what – taught me that a clear box enables me to easily check the blowtorch is present before I drive 150 miles to the apiary.

Where there’s smoke, there’s fire

The easiest – and most hygienic – way to store your hive tool is in a strong solution of washing soda in the apiary. It’s always there and it’s always clean.

But there are times in the apiary when you’ll need a lot more than a smoker and a hive tool.

I’m not referring here to the large items – the spare brood boxes, the supers, the split boards or queen excluders 2.

Instead, I’m referring to the smaller stuff … like the JzBz cage to put the queen into, or the (wickedly sharp) scissors to clip her wing or the Posca pen to mark her.

Just add fingers and thumb for a complete queen marking and clipping kit

Beekeepers have come up with all sorts of fancy carrying boxes made from wood or metal. Jim Berndt described a typical one in Bee Culture a few years ago. Built from 3/4” pine, and with space for the smoker, frame brush, frame hanger and any number of other things.

It must have weighed a ton.

Jim admitted as much when he acknowledged that he’d build the next one from thinner wood.

I’ve seen boxes with integrated seats, or was it a seat with an integrated beekeepers box?

The bee bag

But anything rigid, by definition, lacks flexibility.

If there’s not space in the box for Thorne’s-must-have-gadget-of-2022 (something you only need every other month in the apiary) then you have to carry it separately. If there is space in the box but you only need Thorne’s-must-have-gadget-of-2022 twice a season then the box is heavier and bigger than it need be.

All of which can be avoided by using a cheap bag to carry the necessities down to the apiary.

And what could be cheaper than a supermarket ‘bag for life’ ? 3

A bag for life … or at least 3 years of beekeeping

These bags are light and easy to carry, with strong woven handles. Although they aren’t cavernous (they never have quite enough space for my shopping) they are certainly big enough to carry the essentials, and not-so-essentials, to and from the apiary.

Importantly, they are strong.

Being open and flexible you can, if needed, squeeze all sorts of additional things in.

Although I described them as cheap a better term would be inexpensive. I think they started at about 25p, but they seem to be £1 to £1.25 now.

Being made of polypropylene they are easily rinsed out or wiped clean should they get dirty.

And they will get dirty.

And since they are so cheap inexpensive, it’s not the end of the world if you melt them with the smoker or perforate them with a hive tool.

I’ve used this sort of bag for my beekeeping – not the same one, though they tend to last several seasons – for many years. The Tesco’s centenary was in 2019 and the bag above will certainly get me through to the end of the 2022 season.

Bringing order to entropy

Each winter I sort through the debris that accumulates at the bottom of the bag. I clean everything and get rid of anything that’s been carried around unused for the season. Finally, I replenish the perishables, the worn out or the irreparably damaged.

And then I’m ready for the season ahead 🙂

I don’t just carry around a bag containing a pick’n’mix of jumbled beekeeping paraphernalia 4. The items in the bag are separated into logically-labelled containers for my beekeeping activities.

And long, much repeated and enjoyable field testing has shown that the very best type of containers to use are those designed for ice cream 🙂

Not, I hasten to add, your ’fancy Dan’ Ben and Jerry’s ‘£5 for a couple of scoops’ ice cream in those pathetic cardboardy tubs 5.

Instead, what you need are plastic, square or rectangular (for efficient packing) and with well-fitting lids. Two litre containers are much better than anything much smaller, not just because they’re more fun to empty, but also because they are likely to themselves house smaller containers.

I’m still using some 2.5 litre containers that were sold full of Lidl Gelatelli Vanilla (see the photo above). The ice cream was pretty good but they appear to have stopped making it 6.

I’m sure, if you work hard, you’ll be able to find something equally good … it’s a thankless task, but someone has to do it 😉

What’s in the bag?

I can get everything small I need into two of these boxes – one marked ‘daily’ and the other labelled ‘queen stuff’.

I like to keep the labelling simple to avoid confusion.

Daily

These are the things I use, or might use, on every trip to the apiary:

  • a box containing drawing pins (difficult to use with gloves) and map tacks (easy to use with gloves), together with the red numbered disks I use to label the queen in the hive 7.

A variety of pins, some numbers for queens (see text) and two tubes for sampling weird-looking bees

  • numbers for the outside of the hive
  • marker pen for labelling anything except queens
  • a wired queen excluder cleaner 8 and an uncapping fork for checking drone brood for Varroa
  • spirit level for levelling a hive. This is important if you use foundationless frames. Once you’ve tried to rearrange the frames in an wonky hive full of drawn foundationless frames you’ll realise how useful a small spirit level is 9

Not needed on a daily basis admittedly, but kept in the ‘daily’ box – QE scraper, level and uncapping fork

  • a selection of closed cell foam blocks to hold frames together when transporting hives. These are simply wedged tightly between the top bar and the sidewall of the hive and thereby minimise the risk of crushing the queen (or other bees) when moving the hive.
  • screw cap sample tubes, just in case I see any weird, sick or odd looking bees during inspections
  • a couple of JzBz queen cages
  • digital voice recorder for taking hive notes

Closed cell foam blocks.

Queen stuff

Since a lot of my season is taken up with queen rearing this box contains both the tools for queen rearing and the used-less-than-daily tools needed for marking and clipping the queen:

  • queen marking cage (I like the push and twist ones best, as you can tell from the amount of propolis and paint covering mine)
  • dressmakers snips (Fiskar’s) for clipping the queen. These are very sharp. Don’t leave them in you bee suit pocket or you will get injured 🙁
  • Posca marking pens. Check these in the winter and make sure they haven’t dried up or gone super-gloopy. Either outcome makes for frustration when marking the queen. I only routinely use white, blue or yellow and buy whatever is cheapest or easiest to get, and use that colour for the season (or until the pen expires)
  • tools for grafting larvae and, new this season, the cell punches shown above

Grafting tools. Of these, only the middle (a 000 sable artists brush) one is needed.

  • USB rechargeable head torch (for use when grafting 10 )
  • magnifying glasses 11
  • more JzBz queen cages and some Nicot cages to protect soon-to-emerge cells

What’s in the bag but not in the box?

Inevitably, not everything fits into one of these two conveniently-sized ice cream containers 12.

The base of the bag contains some folded sheets of newspaper which are used when uniting colonies. Before the broadsheets became the same size as the Daily Mail they were preferable as a single sheet would cover a brood box. Now they’ve been shrunk you have to overlap two sheets.

Or read the Financial Times … and there’s very little point in me doing that 🙁

Unstapled newspaper … pictures of an enthusiastic Angela Merkel contrasting nicely with a John Cleese stereotype.

Avoid newspapers that are stapled.

Inevitably when pulling them apart (in a stiff breeze, with an open hive ready to be united) they tear at the staple, increasing your frustration and making you look more like Laurel or Hardy.

I also carry a couple of pieces of fibreglass insect mesh. This stuff is sold by the metre to cover open windows and so keep mosquitoes out, but is ideal for covering an open hive when moving colonies on a hot day. A Thorne’s travelling screen costs £19.40 and works no better than a piece of this mesh which costs £19 less 13. By some sort of miracle I’ve ended up with two colours of mesh, one for standard brood boxes and one for nucs 14.

Fibreglass mesh for use as travel screens (that’s £19 you owe me).

I wear gloves while beekeeping so the bag contains a box of disposable long cuffed latex-type gloves for routine use. There is also be a pair of Marigold washing up gloves for any colonies that are a bit rambunctious 15.

At least there should be a pair of Marigold’s in there … something else to order.

I try and keep a couple of hive straps in the bag.

Finally, you can never have enough gaffer tape … so there’s always a roll in the bee bag. It’s ideal for temporarily sealing hive entrances, strapping nucleus roofs down for transport or patching up holes in the bee bag.

Rejects for 2022

Having sorted through the bee bag I collected a small pile of stuff that wasn’t used last season.

And don’t let me see you in there again! Rejects from the bee bag.

In the case of the ‘crown of thorns’ queen marking torture chamber I don’t think I’ve used it for years. I’ve no idea why it was still in the bag. There’s probably more of my blood on the needle-sharp points than there is paint on the mesh … and there’s clearly no point in me carrying it around for another year.

The awful ‘Chinese’ grafting tool goes out as well, as do some JzBz queen cups, a dodgy pink sparkly Posca pen 16, an ill-fitting pair of magnifying glasses and a shonky magnifier.

And that ‘clip catcher’ … again, almost never used.

Elementary my dear Watson

As I slowly approach very (very) early middle age 17 my presbyopia is becoming more noticeable. I’ve needed magnifying glasses for grafting for several years and, increasingly, in poor light can struggle to see eggs. Unfortunately, about half my beekeeping is done in sub-optimal lighting … the colonies I keep in the bee shed are easy to inspect, whatever the weather, but the lighting is far from ideal.

LED hand magnifier (with some Nicot cups for using when testing if a colony is queenright).

Having chucked out one magnifying glass I’ve found an LED illuminated magnifying glass to try this season. This has a good quality glass lens and a dazzlingly bright set of warm/cool/both LED’s around the rim, powered by a rechargeable lithium battery.

Let there be light. USB rechargeable LED magnifier.

With a choice between wearing reading glasses for all my colony inspections – and inevitably tripping over a super I fail to notice at my feet – or periodically using a magnifying glass if the lighting is poor, I’ve chosen the latter route.

I’ll report back later in the season whether it was the right route to choose.

I’m ready, but the season isn’t

With the unwanted stuff discarded, and the wanted stuff checked and tidied, the bee bag is now ready for the season ahead. I’ve ordered some new Posca pens, charged the magnifying glass and the digital voice recorder …

I’ll probably still look like Fred Karno when I’m floundering around in the apiary, but at least I’ll have the things I need with me.

Unfortunately, it currently looks as though the season isn’t ready for me.

Where did all that lovely weather go?

The last 7-10 days have been stunning, but it’s currently 3°C and snowing 🙁

Which is probably fortunate as I still have a couple of hundred frames to build …


Note

I first wrote about the bee bag way back in November 2016. Time has passed, the contents of the bag have changed a bit (though the jokes are largely the same) so that page now redirects here.

It makes you go blind

Synopsis: There is a sexual arms race between the queen and the drones she mates with. The queen needs to mate with multiple drones to maximise colony fitness. Conversely, it’s in the interest of individual drones to reduce the number of additional partners who mate with the queen. Recent studies have demonstrated that drones reduce repeat mating flights by impairing the eyesight of the queen. Potential implications of this for practical beekeeping are discussed.

Introduction

Honey bee queens are described as polyandrous 1 because they copulate with multiple drones during one or more mating flights taken shortly after emergence.

These multiple matings are a risky business 2.

It takes longer to mate with multiple drones than it does to mate with one, but this time is minimised by reducing the number of mating flights. Rather than leaving the hive, mating once, returning and then repeating the process, the queen flies some distance to a drone congregation area and copulates with multiple drone before returning to the hive.

Shallow depth of field

One of many …

I’ve discussed the location and locating drone congregation areas previously and the distances the queens and drones respectively fly to reach these (which are different to avoid inbreeding).

Between the queen returning from the mating flight and the onset of egg laying there is a delay of a few days. During this period the queen is storing the sperm from the drones in her spermatheca. These are the sperm storage organs within which sperm stays active for years … a necessity as, after the onset of laying, the queen will not go on any more mating flights.

Perhaps surprisingly, only about 3-5% of the sperm transferred from each drone is stored by the queen.

I hope that makes you wonder why she bothers mating with so many drones … it should.

Polyandry and hyperpolyandry

Just before I explain why she only stores 3-5% of the sperm from each of several drones, rather than storing it all from one twentieth the number (and thereby reducing the risks of longer mating flights) of drones, I need to explain the poly bit of polyandry.

How many drones does the queen mate with?

The usual figures quoted are in the high teens, with a range extending from single digits into the low forties. These numbers are determined using a variety of different techniques, at least some of which are likely to underestimate the actual number of drones.

Marked queen surrounded by a retinue of workers.

Here’s one I made earlier …

Think of it like this, if you have a large population of something – like beekeepers – how many would you have to ‘sample’ to find one called ’David’.

Not many, it’s a common name.

But what about ’Atlas’ or ’Zebedee’?

You’d have to sample a lot more apiarists to find any with these rarer names, though I bet they’re out there somewhere. You might even have to use a different way to screen the population.

And it’s the same when determining the numbers of drones that the queen mates with.

Search and ye shall find – detecting rare patrilines

When you use a method that specifically looks for rare patrilines – essentially genetically distinct offspring fathered by different drones – you can find them. This suggests that the queen probably mates with more than the 15-19 drones usually quoted, and that hyperpolyandry is perhaps a better term to describe the mating behaviour of queen honey bees.

There’s evidence that these very rare patrilines (so-called ‘Royal patrilines’) are preferentially selected when rearing queens under the emergency response.

Colony fitness

So now we’ve defined what the poly in polyandry means … but we still don’t know why the queen risks all those aerial shenanigans to mate with so many different drones.

By mating with multiple drones she ensures that the workers in the colony are genetically diverse. This genetic diversity increases the rather-difficult-to-grasp concept of colony ‘fitness’. In this instance fitness is used to mean a combination of adaptability, resistance to stress or pathogens, increased foraging activity, better overwinter survival etc.

I’ve discussed this concept before and suggest you revisit that post for all the gory details.

The bottom line is that colonies that are headed by queens that are mated with very many drones (50+) produce more brood, have better disease resistance and have many other desirable traits (that benefit both the colony and the beekeeper).

The final piece of this introductory jigsaw I need to mention is that drone sperm is used randomly. It’s not a case of ‘first in, last out’. The 3-5% of sperm stored from each drone is mixed thoroughly in the spermatheca.

This makes sense in light of the comments above about colony fitness. If the sperm were used in batches from each drone you’d have cohorts of young bees being produced that had reduced genetic diversity, thereby potentially compromising colony fitness.

It takes two to tango

But let’s think about the poor drones for a moment.

Drones have two fates (excluding getting eaten by a bee eater); they either die while mating with a queen, or they get turfed out of the hive and starve to death towards the end of the season.

If the drone fails to mate with a queen he’s genetic dead end.

If he does mate with a queen there’s a good probability that the genes he carries will be passed on to the following generation.

There is therefore a lot of competition for the queen in the drone congregation areas (DCA).

The drones, once sexually mature, fly every (suitable) day to several DCAs, one after the other. In addition, they fly relatively short distances from the hive to maximise their time within the DCAs.

Heat map of the landscape used by drones – bright spots are DCA’s

This competition is intense, and it doesn’t stop once the drone has mated (and died).

If a queen mates with a relatively small number of drones – let’s say 10 for the sake of argument – the chance of the sperm from any one of those drones being used to fertilise an egg is much greater than if the queen had mated with 50 drones.

The fewer drones the queen mates with the better the chances that the genes from any one of her successful suitors will be passed on to the following generation.

Paradoxically, it therefore benefits the drone 3, if the queen mates with fewer other drones.

And, remarkably, drones have evolved a way to reduce the number of additional drones that a queen mates with.

A sexual arms race

Before I describe the mechanism, it’s worth emphasising here that best interests of the colony are served by the queen mating with many drones, but those of the drones are best achieved by limiting the polyandrous activity of the queen.

These two processes are therefore in direct competition.

There are some additional subtleties.

If the drone simply prevented the queen from mating again 4 it would be detrimental if that drone was the first with which the queen mated. The resulting colony would have little genetic resilience and would be unlikely to survive.

Any one drone must therefore allow the queen to mate with sufficient other drones to ensure colony fitness.

In addition, the more mating flights that a queen goes on, the greater the chances she will be predated by a passing bird, or get lost on the return flight.

From the drones point of view it would probably be beneficial for the queen to go on only one mating flight, but that she mates with sufficient (but no more than that) drones on that flight.

And finally, before I get to the mechanism by which all this is achieved – a compromise solution, like all the best solutions – I’ll remind you that studies have shown that queens go on about 5 mating flights spread over 3, usually successive, days.

Love is blind

At least, too much love is … 😉

Liberti and colleagues have recently published a snappily titled paper on how drones reduce the number of mating flights taken by a queen. The paper is Open Access so you can get all of the nitty-gritty details I don’t have time, energy or intelligence to include in the summary below.

The paper is:

Seminal fluid compromises visual perception in honeybee queens reducing their survival during additional mating flights by Joanito Liberti et al., (2019) eLife 2019;8:e45009

As with all science, the results published in this paper were a continuation of earlier studies of queen honey bees. In particular, these included studies by some of the same authors who had showed that seminal fluid contained proteins that had the ability to interact with neurons.

In addition, in Drosophila melanogaster (the fruit fly, and genetically best studied insect) there was evidence to suggest that seminal fluid promotes fast oviposition and reduces the willingness of females to seek additional copulations.

Drosophila mating in captivity

Now, Drosophila mating behaviour is very different to that of honey bees, but there was clearly a precedent here in which some of the components of seminal fluid – the ‘carrier’ that keeps sperm alive and motile and protects against pathogens – influenced subsequent mating in insects.

Or the lack of mating.

The study by Liberti et al., involves an elegant combination of hardcore molecular gene expression analysis coupled with electroretinography 5 and field work. I’ll skip briefly through the first two of these and provide a bit more detail on the last.

Analysis of gene expression

Virgin queen bees were instrumentally inseminated with seminal fluid (i.e. no sperm) or a control saline solution. Subsequent analysis of the brains of the bees – using a method called RNA-Seq which allows the qualitative and quantitative changes in gene expression to be accurately determined – demonstrated reproducible changes in the gene expression of dozens of genes.

Venn diagram of differential gene expression in instrumentally inseminated queen bees

Detailed analysis of which genes had changed in expression showed that several so-called signalling and metabolic cascades were modified in response to seminal fluid, and many of these mapped to the phototransduction pathways i.e. those involved in sight.

Several of the genes that were detected encoded proteins that were implicated in the conversion of light into the electrical signals in photosensitive electrical cells.

Inevitably, that one sentence has probably confused half the readers that have persevered to this point in the post …

Essentially what this means is that there are components within drone seminal fluid that change the ability of the queen to perceive light, or to see.

So, do they?

Visual perception of queens

The gene expression studies in this paper are complicated (for a molecular biologist). The electroretinography is an order of magnitude more complicated for this molecular biologist to understand … but here goes.

Electroretinography involves measuring the electrical signals generated by particular neurones that are connected to the compound eyes and ocelli 6. This allows the consequences of the changes in gene expression to be determined in terms of the vision of the queen bee.

These studies showed that queens instrumentally inseminated with seminal fluid had lower responses to low frequency flickering light, and that that this response (or lack of response) increased on the second day after insemination.

There were additional changes in the response of the ocelli in queens inseminated with seminal fluid.

Taken together, these results show that queens exposed to seminal fluid experience reduced visual performance.

They are not blinded, but their vision is impaired.

Does this visual impairment have any influence on their mating behaviour?

Mating flight behaviour

Finally, we come to something that’s a bit easier to comprehend, not least because I’ve previously discussed the technology used – the RFID tagging of individual bees to monitor their flight frequency and duration.

RFID-tagged queens (34 in total) were instrumentally inseminated (either mock, or seminal fluid or semen) and subsequently monitored when going on mating flights. Those receiving either seminal fluid or semen were more likely to get lost on these flights, and repeatedly triggered the hive entrance sensors, suggesting they were disorientated by sunlight after leaving the hive.

Of the 21 queens that returned, 81% went on mating flights of more than 7 minutes which was considered a conservative threshold for a completed mating flight i.e. flight to a DCA, mating(s) and return to the hive, and about 50% laid worker brood.

Notably, of the 17 queens that went on ‘successful’ (by duration, not necessarily by outcome) mating flights, those receiving the control saline solution left 1-2 days later than those that had received seminal fluid or semen.

Seminal fluid and semen induce alterations of mating flight behaviour in honeybee queens

These results show that exposure to seminal fluid induces significant changes in queen mating flight behaviour, presumably as a consequence of the alteration to the vision of the queen.

Therefore, the implication from these results is that proteins in the seminal fluid of drones impairs the visual perception of queens, thereby reducing the likelihood that the queen will embark on additional mating flights.

Queens that had already mated (or been instrumentally inseminated in this study) were more likely to get lost on subsequent mating flights, and embarked on these flights earlier.

But what about swarming?

The hive – or a natural nest site – is a low-luminance environment. Queens do not need fully functional eyesight once they have returned from their mating flights. In the hive communication is non-visual, mediated by pheromones, contact, vibrations and sound.

However, although a queen only goes on a few mating flights, she will also leave the colony if it swarms.

Swarm of bees

Swarm of bees

What are the implications for the this study on the eyesight of queens during swarming?

This isn’t really discussed in the paper, but I think there are two likely scenarios:

  • the changes in visual perception by the queen are transient and return to ‘normal’ after a few days, weeks or months
  • swarming is a fundamentally different activity in which thousand of bees leave the hive and for which accurate vision is not needed by the queen.

There’s a world of difference between embarking alone on a mating flight of several kilometres and having to return to the exactly the same location, and leaving on a one-way trip with a swirling mass of attendees with dozens of scout bees leading the way.

Further studies will be needed to determine whether the changes in vision are transient or permanent, as well as to identify the ‘active ingredient’ in seminal fluid that is responsible for the degradation of the mated queen’s vision.

I also think further studies will be required to determine the relationship between dose and timing of the response.

How long does it take for the reduction in visual perception? If the first and second mating flight are taken on successive days is the “return rate” greater than if they are taken a few days apart?

How many drone matings are needed to reduce the visual acuity of the queen? I would predict that this would be a number consistent with the lower estimates of polyandrous matings needed to generate fitness in the resulting colony.

And implications for practical beekeeping?

Perhaps none directly, though I’m interested in the answers to the questions I posed in the paragraphs above.

In an area with low drone densities and those with shall we say ‘variable’ weather – such as my apiaries on the west coast of Scotland (or for that matter, any beekeepers living in remote northerly areas with just a few hives) – is colony fitness compromised by reduced matings?

An isolated apiary

Conversely, is mating success lower because more queens fail to return from subsequent mating flights that they have to take to try and mate with enough drones?

Can mating success and colony fitness be increased by boosting drone numbers?
And is this achievable at a scale meaningful to a small-scale beekeeper?

If a measurable increase in mating success took a 1000-fold increase in drone numbers it’s probably not achievable.

However, if all it took was an extra frame of drone comb in every hive in the apiary, then that’s quick win.


 

Triumphs and tragedies

Synopsis: Having dealt with beekeeping tragedies last week, it’s now time to consider landmark events (‘triumphs’) in beekeeping. These four things – successful overwintering, swarm control, finding the queen and queen rearing – are what I consider the most notable. All beekeepers should be able to achieve these, and their beekeeping will benefit as a consequence.

Introduction

In the second part of the highs and lows of my (or an average beekeepers’s 1 ) beekeeping career I discuss what I consider are the four most significant events in the progression from total beginner to my current level 2.

These highs and lows, or ‘triumphs and tragedies’, stemmed from a question posed during a live-streamed Q&A session with Lawrence Edwards from Black Mountain Honey. I didn’t think I answered it particularly well then – though some of the things below were definitely included – so have had another crack at it.

The tragedies I covered last week – the loss of a queen, a swarm or a colony – aren’t really tragedies. As I said in the introduction then, ” … the observant and well-prepared beekeeper can avoid most of the ‘tragedies’, and recover from almost all of them”.

However, unlike the tragedies that really aren’t tragedies, these triumphs really are landmark events that significantly improve your beekeeping.

Unsurprisingly, some of the triumphs I discuss below are how you recover from – or avoid altogether – the tragedies I mentioned last week.

Successful overwintering

Studies from Tom Seeley (in his book The Lives of Bees) indicate that a swarm from a wild-living colony has about a 23% chance of surviving the winter. Swarms perish for a number of reasons; many starve to death, others die from pathogens 3, a few queens likely fail and some colonies are lost due to ‘natural disasters’ such as lightning strikes or storms or bears.

Although I don’t know the percentage breakdown of these causes of death, I’d be surprised if the combination of queen failures and ‘natural disasters’ account for more than a small percentage.

In contrast, I expect that starvation and disease account for most losses of ‘wild’ colonies.

Hives in the snow

The survival rate of managed colonies is not entirely clear as it differs with the group or individual being surveyed.

The relatively small-scale annual BBKA surveys suggest that about 80% (the average of the last 12 years) of colonies overwinter successfully. The much larger Bee Informed Partnership surveys 4 report a slightly lower figure of 70%.

Finally, the COLOSS surveys – covering Europe and a few other countries 5 – helpfully split winter losses into those due to ‘mortality’ (presumably disease and starvation) from queen failure and natural disasters, and usually report survival rates of 70-80% 6.

COLOSS reports losses due to queen failure and natural disasters are typically about 5-7%.

Let’s assume for the sake of argument that these are unavoidable, and that they’re as likely to befall a managed hive as a ‘wild’ colony.

Averages, outliers and being ‘better than average’

These losses, when analysed statistically, show considerable variation between individual beekeepers. Some never lose colonies during the winter, others often experience high rates of colony mortality.

When I last checked 7 all my colonies have survived this winter. My average losses over the last decade (about 200 ‘colony winters’) are well below 10%. Many of the experienced beekeepers I know routinely experience losses in the 5-10% range.

In contrast, inexperienced – and sometimes longstanding 8 – beekeepers may lose many or even all the colonies they ‘manage’. Many give up, others make up the losses through splitting, swarms or purchases, and soldier on to the next winter, only to experience the same disappointment again 9.

Winter losses ...

Winter losses … dead bees on the floor of a hive with a failed queen.

Some losses are expected – though perhaps no more than the ‘unavoidable’ 5-7% due to ‘natural disasters’ and queen failures.

However, the remaining 90-95% of colonies should survive, particularly if we assume that their loss would be due to starvation or disease … both of which squarely fall under the term ‘management’ when considering managed colonies.

This management is the responsibility of the beekeeper – s/he must ensure that the mite (and consequently virus) levels are minimised at the right times during the season, and that the colony has sufficient stores to overwinter successfully.

Take your winter losses in autumn

The final point to remember is that the successful management of colonies involves excluding those from going into the winter that are likely to fail.

Weak colonies in late autumn, or early autumn queen failures, are often doomed anyway.

Don’t let them become a (BBKA, BIP or COLOSS) statistic.

If healthy, unite these colonies with strong colonies and then plan for some additional splits the following season to make up the ‘on paper’ loss. Far better you strengthen another colony than condemn a weak colony, or one with a poorly mated queen, to a lingering death in midwinter.

Uniting a strong colony with a weak (queenless) colony

I therefore consider the first landmark event (‘triumph’) in beekeeping is the successful overwintering of the majority (over 90%) of the colonies managed – irrespective of the severity or duration of the winter.

Achieving this involves a combination of skills:

  • successful disease management (which I term ‘Rational Varroa Control’)
  • appropriate feeding in the autumn
  • the ability to judge colonies unlikely to survive before it’s too late to unite them
  • well-sited apiaries unlikely to flood or be hit by falling trees (or visited by rampaging bears)
  • provision of young and well-mated queens to head colonies

A strong and healthy colony is likely to overwinter successfully. It’s also more likely to build up strongly the following spring, and therefore will probably swarm … or at least try to.

Which neatly takes me to the second of the ‘triumphs’ that a beekeeper should aim to achieve.

Successful swarm control

Swarm control is the management of a colony that has started making queen cells, and is therefore likely committed to swarm within a few days.

It is a necessity if (or when!) swarm prevention stops working.

I visited one of my apiaries last week. There were a dozen colonies in the apiary last year and I know I missed one swarm.

‘Missed’, but not ‘lost’.

I’d found the bivouacked swarm, dropped it into a nuc box and successfully re-hived them 🙂

Collecting the stragglers – a captured bivouacked swarm dropped into a nuc box.

However, while taking some willow cuttings I discovered wax deposits on another of the small trees I’d planted.

Clearly a swarm had bivouacked here for a day or so and I’d both missed and lost it 🙁

Missed and lost – signs of a bivouacked swarm on a small willow.

For the last couple of seasons, while living remotely, I’ve usually been very pro-active in my swarm control.

If a few colonies in the apiary start building queen cells I use the nucleus method of swarm control and take the queens out of all the strong colonies and then allow them to requeen.

For swarm control the nucleus method is almost foolproof.

It is very successful in preventing the loss of a prime swarm (one with the mated queen). However, with really strong colonies, there remains the risk that more than one virgin queen emerges. I suspect I’d missed a queen cell and lost a cast headed by a virgin queen. I know that all my colonies requeened successfully and without unexpected delays.

So, this was an example of unsuccessful swarm control, but it was less of a problem than the loss of a prime swarm (as I still had the mated queen tucked away in a nuc somewhere).

Timing and mechanics

Successful swarm control involves the ability to recognise when a colony is actively making swarm preparations i.e. being able to find queen cells, and then knowing exactly what to do (and when to do it) to prevent the colony from swarming.

Queen cells ...

Queen cells …

The first is observational and will improve the more hives you inspect (or should if ‘seeing’ is coupled with ‘understanding’).

The second – ‘what and when’ – is the mechanics of swarm control:

  • find and isolate the mated queen somehow (Pagden or vertical split, nucleus etc.) in a way that ensures her survival. Her continued availability is important if the original colony does not successfully requeen.
  • find all the queen cells and leave sufficient to ensure the colony can requeen but not so many that the colony generates casts. I usually leave a single charged queen cell (but clearly left more than one in the colony that swarmed onto that willow above).
  • the ability to judge that the colony has successfully requeened and that the new queen is well mated, so guaranteeing the survival of the colony.

There are dozens of different swarm control methods. Most share some common features in terms of actions and timing.

However, that doesn’t mean that you can ‘mix and match’.

  • Learn one method.
  • Know when to apply it. Understand its pros and cons.
  • Have the equipment to hand during the ‘swarm season’.
  • Analyse what went wrong if it doesn’t work.

Achieve all this and you will be successful at swarm control, your colonies will be stronger during the peak nectar flows of the season, you’ll collect more honey and they will overwinter more successfully.

Swarm control – knowing what to do when, and employing it successfully – moves you from hit and hope scrabbling around with “Finger’s crossed they won’t swarm” to a reassuring 10 “What will I do with the additional colony?

It’s a real confidence builder … and while we’re on the topic of confidence.

Finding the queen … quickly, and every time

Watch a new beekeeper look for the queen. They will sequentially and thoroughly inspect every frame in the colony. Each frame is turned and rotated slowly as taught in the winter ’Start beekeeping’ courses. They’re often particularly careful to check the sidebars and the bottom bar of the frames. The underside of the queen excluder (QE) is carefully scrutinised.

A gentle puff of smoke every couple of frames keeps the colony nicely subdued.

Fifteen minutes later they find her, on a frame of stores. The frame had already been inspected at least once 🙁

She’s somewhere in there …

In contrast, an experienced – and good (!) – beekeeper gently lifts the QE, checks it briefly and closely observes the density of bees along the visible seams. She then uses a small amount of smoke to allow the dummy board and outer frame to be removed. These are carefully placed aside.

The beekeeper then splits the remaining frames where the density of young bees is the greatest, opening a 2 cm gap. The nearer frame facing the gap is then carefully removed and the queen will usually be found on it, or on the far side of the other frame facing the gap.

It’s all over in 90 seconds and – to the inexperienced – it looks like magic.

It’s not.

Blue marked queen ...

Blue marked queen …

It’s also not 100% guaranteed, but it happens enough that it’s certainly not chance.

Of course, you don’t need to find the queen to be reasonably certain the colony is queenright.

Usually their behaviour, the presence of eggs and the absence of sealed queen cells is a sufficiently good indication that there’s a queen present.

Gently does it

But, when you do need to find her – for example, to employ one of those swarm control methods that requires the isolation of the queen 11 – the 13.5 minutes saved by the good beekeeper really helps avoid frustration (and agitated bees).

In the example above the beginner found the queen on a frame of stores, almost certainly because he disturbed the colony using too much smoke and by slowly going through the box frame by frame. The queen was ‘chased’ across the box, scuttled across the floor or around the sidewall of the hive and ended up on the outer frame of stores or pollen.

The experienced beekeeper used almost no smoke. The bees barely knew she was there. She split the frames where there were more young bees. These will be tending the queen and the young larvae. If the queen wasn’t on the face of the first frame checked she’s likely to be on the reverse of the facing frame (having moved there to avoid the light streaming in through the gap between the frames).

You can keep bees without being able to find the queen, but certain things are much easier if you can reliably and quickly locate her.

This is a skill that some never acquire and that others seem to naturally possess.

But it can also be learned.

It’s easier to do with a calm and gentle colony.

However, it’s perhaps learned fastest with a double brooded box of suicidal psychotics 😉

And, if you’re good at finding the queen you will be asked 12 to requeen one of those double brooded boxes of suicidal psychotics.

Which is why this third landmark event in your beekeeping is inextricably linked to my final choice … the ability to actively rear high quality queens.

Queen rearing

Of all the things I’ve learned since starting beekeeping – including the huge number of things I’ve subsequently forgotten – queen rearing has been, without doubt, the most useful.

I’m talking here about ‘active’ queen rearing, rather than passively allowing a queenless colony to generate queen cells and requeen itself.

There’s absolutely nothing wrong with this ‘passive’ approach. I use it every year. However, it doesn’t teach you as much about beekeeping.

I consider the following are the direct and indirect benefits of active queen rearing. These justify inclusion of queen rearing in this list of landmark events in beekeeping:

  • to be successful you need the ability to judge the quality of the bees over the course of the season. There’s no point in rearing queens from poor quality stock.
  • rearing good quality queens means you can readily improve the quality of your colonies, simply by requeening them. You should see the benefits in 2-3 years (or months in the case of some colonies I’ve requeened 😉 ).
  • queen rearing means you need to acquire the skills and confidence to find and (often) handle the queen. Marking and clipping the queen makes your beekeeping easier.

Returning a marked and clipped queen

  • you can readily achieve sustainability in your beekeeping. No need to buy in queens or nucs. No need to rely upon capturing swarms to maintain colony numbers.
  • you can have spare queens and nucs available when you need them, or generate surplus for gift/sale.
  • young queens – which you ensure by requeening – head stronger colonies, are less likely to swarm and overwinter better.
  • queen rearing requires understanding the colony manipulations needed to start queen cell production. This necessitates good observation and skilled beekeeping.

And there are probably as many again that I could include if I hadn’t already written 500 words more than I’d intended 😉

The most fun you can have with a beesuit on?

However, almost as importantly … “of all the things I’ve learned since starting beekeeping – including the huge number of things I’ve subsequently forgotten – queen rearing has been, without doubt, the most”enjoyable.

Perhaps not ‘the most fun you can have with a beesuit on’ 13 but pretty darned close.

Actually, I’ve already thought of a few more things that should be in the list above:

  • the skill to prepare nucs for queen mating (either mini-nucs or 2-5 frame nucs). And subsequently manage them.
  • an ability to have nucs available for overwintering to make up losses or for (profitable) sale early the following season.
  • the confidence to dabble with methods for colony preparation to find strategies that suit your own bees and the local environment.
  • out-of-season projects to entertain you (like building my wildly over-engineered queen cell incubator) during the interminable dark winter months.
  • etc.

Portable queen cell incubator

Only a relatively small percentage of beekeepers actively rear queens.

I suspect many are dissuaded because they think it requires skills they don’t have, and are unlikely to acquire without years of practice.

Au contraire as a Gilles Fert, a well-known French queen rearer, would say.

You may not (yet) have the skills but few of them are ‘mission critical’ and most can be learned relatively easily. 

Of the four things discussed in this post, queen rearing is the skill that has provided the greatest benefit to my beekeeping.

And enjoyment.

Go forth and multiply 🙂


 

Queen mating flights

Synopsis: How far does a queen fly to mate? Studies using RFID-tagged queens are providing insights into the frequency, duration and temperature dependence of queen mating flights … all of which have practical implications for beekeeping.

Introduction

Although it tends to be a rather poor topic of conversation at dinner parties 1, I’m getting increasingly interested in the mating biology of honey bees. This is an essential part of the life cycle of our bees, and one that has been – and continues to be – well studied.

Marked queen surrounded by a retinue of workers.

Here’s one I made earlier …

When I lived in the Midlands there were a seemingly endless supply of bees in the area. Beebase reported that there were about 200 other apiaries within 10 km of my main apiary. Assuming an average of 5 hives per apiary 2, and ignoring any wild or feral colonies, that’s 1000 hives producing drones with which the queen could mate 3.

Of course, it’s not quite that simple, but bear with me.

In Fife, on the east coast of Scotland, my apiaries are in areas with about 35-40 other apiaries within 10 km, so – using similarly dodgy maths – perhaps 200 hives.

Nevertheless, bees are in apparently plentiful supply.

What do I mean by ‘plentiful’?

As a beekeeper, the two main ways – other than Beebase or by physically searching for them – I can judge the numbers of bees in the environment are, the:

  • success of my bait hives in attracting swarms 4, and
  • the ease with which my queens get mated

If I catch lots of swarms and a high percentage of my queens mate successfully then there must be a lot of bees about.

Apiary density

I was intending to start this post with a discussion of the evenness or otherwise of the distribution of apiaries within the Beebase-defined 10 km radius.

However, it turns out 5 that my maths are not good enough to plot a truly even distribution of hives/apiaries 6. Anyway, common sense dictates that apiaries are not evenly distributed … so let’s instead just consider the number of hives per square kilometre within that Beebase 10 km boundary.

Neighbouring apiaries, hive density and queen mating distances (see text for details)

In the diagram above the enclosing black circle indicates the area within which Beebase reports ‘neighbouring’ (i.e. within 10 km) apiaries. Inside that I’ve shown just four of the 314 one km2 blocks (in blue). On average, in the Midlands each of these would contain ~3.2 managed hives 7. In Fife, there would be – on average again – about 5 times fewer hives per blue square.

Several studies suggest that drones fly relatively short distances from the hive to the drone congregation areas (DCA) where they loiter with intent’ (of finding a virgin queen to mate with). I’ve discussed the use of harmonic radar tracking studies to identify these locations.

So, how many of these hives are actually within the range of a queen on a mating flight?

Where do you go to my lovely?

I posed the question How many of these hives … ? as we don’t know where the actual DCAs are.

The radar mapping study identified several within a few hundred metres of three drone producing colonies, so it seems reasonable to simply assume the DCAs are near the hives, and we know the average density of these.

Harmonic radar tracking of tagged queens visiting DCAs was not successful. It’s a short range technique, and the queen is known to sometimes fly long distances to visit DCAs.

I’ve discussed some of the studies used to determine these long-distance virgin queen flights, but summarise them again here:

  • In studies almost 90 years ago, Klatt observed successful mating on an isolated peninsula when the queen and drones were 6.3 miles (10.1 km) apart
  • In the mid-50’s Peer 8 demonstrated matings could occur when the queen and drones were 10.1 miles (>16 km) apart
  • Jensen 9 demonstrated mating when the queen and drones were 9.3 miles (15 km) apart

Of course, in all these studies it was not determined whether the queen and drones flew similar distances to the DCA. Since we know that drones probably fly relatively short distances it’s likely that the queen does the majority of the leg wing-work.

Ignore the outliers

The Peer studies showed that, although mating could occur when drones and queens were very widely separated, there was an inverse relationship between mating success and distance.

Just because 5% 10 of queens can mate following combined flight distances of 15 km does not mean that’s the distance they usually travel.

Actually, if only 5% of queens get mated at that distance then we can be pretty sure they usually fly much shorter distances.

Fortunately, Jensen did a more thorough analysis of this and showed that 90% of all matings occurred within 4.6 miles (7.4 km) and 50% within 1.5 miles (2.4 km).

And those are the 50% and 90% circles plotted on the diagram above, encompassing an area of 18 km2 and 174 km2 respectively.

Or, to express that area in potential drone donor colonies, 58 or 548 respectively in the Midlands, with a hive density of 3.2/km2 11.

So, in areas with reasonable densities of bees, knowing the majority of queens fly no more than 7.4 km, there are potentially hundreds of colonies producing drones that the queen could mate with.

All of which is a rambling introduction to looking at queen mating distances using a different approach.

Rather than work out how far she flies, what happens if we measure how long she takes?

If we know how fast the queen can fly we can again calculate distances and the number of potential drone producing colonies within range.

Time and weather dependence

But there are additional advantages of looking at queen mating flight duration.

If we can do it accurately we can also determine the:

  1. time of day when most mating flights take place,
  2. influence of the weather on the duration and frequency of queen mating flights,
  3. number of orientation and mating flights the queen takes.

And frankly, as a practical beekeeper, I’m much more interested in the first two of these than I am in the absolute distance she flies for her dalliances.

In an area well-populated with hives, understanding when the queen is likely to be away on a mating flight will help me avoid interrupting her return, and determining when she is likely to start laying.

But, as a scientist, I’m also really interested in the third point as there is some interesting recent work to suggest that drones try and restrict queens taking multiple mating flights 12.

Heidinger et al., studied the mating behaviour of queens using radio frequency identification (RFID) tags 13. Although the study produced no dramatically new results, it was a neat application of technology and allows me to discuss when mating flights occur and the influence of the weather in a little more detail.

The paper is Open Access if you’d like to read it. I’m not going to go through every subtle wrinkle and nuanced argument in the study, but will instead just focus on the important ’take home message(s)’.

RFID tagged queens

This is something I don’t need to discuss in anything other than cursory detail as I wrote about it three weeks ago in ’Chips with everything’.

Or perhaps I do? The post was only read by about 25% of the visitors who read the following week’s ’What they don’t tell you’ … it’s almost as though the hardcore science is less interesting than anecdotes about starting beekeeping. Surely not?

Essentially you stick a unique tag onto a bee and record when it enters or exits a hive using a sensitive reader at the hive entrance.

RFID tagged bees and RFID readers on a feeder

You don’t need to stand by the hive and watch anything.

All the ‘observations’ are made automagically and recorded digitally for subsequent analysis. You can therefore monitor hundreds of workers or dozens of queens simultaneously, thereby increasing the statistical robustness of the results obtained.

The Heidinger et al., study monitored the mating flights of 64 queens.

Of these, 11 were ‘missing in action’ 14 and never returned to the mating nuc.

Fifty three (83% … a figure very close to that quoted above from completely different studies) mated successfully and started laying eggs. However, two of these managed to get out and mate successfully without ever being detected by the RFID reader, meaning that flight times, frequencies and durations are from 51 queens 15.

The study was conducted in two apiaries about 4 km apart in Middle-Thuringia, Germany, in June/July.

Logistics and data wrangling

Conducting these types of field studies is not straightforward. Queens have to be produced in batches and then introduced to mating nucs.

A week of bad weather means the queens will have aged before they have a chance to fly.

What do you do about queens that return from a mating flight but that cluster underneath the mating nuc, only entering (and triggering the reader) after an hour or two?

To accommodate these vagaries the authors:

  • grouped queens according to age,
  • considered flights less than 3 minutes long as orientation flights
  • ignored mating flights of longer than one hour

And whatever filtered through from that pre-screening was then subjected to rigorous statistical analysis.

Time and duration of mating flights

Queens went on mating flights for 1 to 5 days, with an average of 2.2 +/- 0.98 day 16. In easier-to-comprehend terms this means that about 70% of all the queens went on mating flights on 1 to 3 days.

Since it’s often quoted that queens leave the hive ‘once to mate’ this might be a surprise to some.

Perhaps even more surprising is that queens went on a total of 1 to 16 mating flights, with an average of 5.04 +/- 3.11.

One particularly enthusiastic queen went on 7 mating flights in one day. The very definition of ’hot to trot’.

The timing of queen mating flights

Over 80% of these mating flights took place between 1pm and 4pm. From a practical beekeeping standpoint, by avoiding this period for hive inspections you will significantly reduce the chances of being in the way when a queen returns to a mating nuc.

The duration of mating flights

The average length of a mating flight was a bit less than 18 (17.69 +/- 13.19) minutes. Of approximately 255 mating flights (i.e. flights of 3-60 minutes duration) monitored, about 180 (70%) were of 20 minutes or less.

All of these results are in pretty good agreement with a wealth of literature collected using different methods over the last few decades.

Can we use some of these figures to calculate queen mating flight distance?

Duration x speed = distance

I can find nothing in the literature on the speed at which a queen flies. However, I do know that the escapee virgin queens I try and catch usually fly just too fast 🙁

Let’s assume for the sake of argument that the queen flies at about the same speed as a worker bee. This is usually reported as 25 km/hr unladen and about 17 km/hr when laden with pollen or nectar.

Therefore, a queen mating flight of 20 minutes at 25 km/hr involves flying a total distance of no more than 8.3 km. A 10 minute mating flight at 17 km/hr equates to 2.8 km.

These distances include three components, an inward and outward leg separated by the flight time within the DCA. Your guess is as good as mine as to how long the latter takes 17.

However, not knowing something is the perfect opportunity for some informed speculation (or, as here 18, wild guesswork).

Wildly uninformed guesswork

The queen mates with several drones while in the DCA. Although each mating takes a very short time (seconds) there is competition between the drones while they chase the queen, so she must stay within the DCA for a reasonable period.

Time for another assumption … this time let’s assume that the queen spends one third of the duration of her mating flight within the DCA or 4 minutes, whichever is the shorter 19.

If that were the case, a 10 minute mating flight at 17 km/hr, with a third of the flight time being spent in the DCA, would mean the mating site was just 940 metres from the hive. Conversely, if the queen spent no more than 4 minutes in the DCA during a 20 minute mating flight at 25 km/hr, then the mating site must be 3.33 km from the hive.

Either my guessestimate for the time spent in the DCA is too high (quite possible), or the predicted flight speed of the queen is too low (unlikely to be wildly wrong, she’s not going to rush there at 75 km/hr) … or the typical distances queens travel to a DCA are significantly less than those measured using isolated queen and drone-producing colonies in the studies cited earlier by Jensen, Peer or Klatt (see above).

Relationship of time spent in DCA and potential maximum mating flight distance

The table above shows why I think queens likely spend less than 4 minutes in the DCA. Distances in red are within 2.4 km that Jensen showed 50% of matings occur in, those in yellow are within the 7.4 km that 90% of matings occured in 20.

The influence of the apiary

Let’s stop all this wild guesswork and return to the calming certainties of statistically compelling data 😉

The Heidinger study involved two apiaries separated by a few kilometres. All the data discussed above uses recordings pooled from both apiaries. However, queens in one apiary went on more mating flights than in the other. The difference isn’t huge (5 vs. 4 flights in the first three flight days), but is statistically significant.

Mating flight number (a) in different apiaries, and (b) at different temperatures

The queens are described as ‘sister queens’ and I assume this means they are all reared from larvae from the same mother queen, though this isn’t made explicit. If that is the case, it suggests the geography of the area influences queen mating flight frequency.

I say geography, rather than drone availability, as they also added an additional 47 (!) drone producing colonies near one apiary and observed no influence on queen mating flight characteristics.

Although the number of mating flights the queens went on differed, the duration of the flights did not.

The data start to get a bit more complicated when they considered the age of the queens and the duration of the first, second, third etc. flight … so I’ll skip all that and finally just consider the influence of temperature on mating flights.

Some like it hot

It is regularly stated that virgin queens need calm, sunny afternoons with a temperature exceeding 20°C before embarking on mating flights.

This is somewhat disconcerting for a beekeeper living on the cool/wet/windy – but exceeding beautiful – extremities of the UK.

July rain squalls across Mull, Skye and the Sound of Sleat

In fact, mating flights – by which I mean flights of 3-60 minutes (as no record of successful mating on individual flights was made) – occurred in the Heidinger study between a range of 14°C and 25°C.

In cooler weather, queens tended to take more mating flights (shown in the right hand panel on the graph above). The line is a ‘best fit’ and it’s clear there is quite a bit of variation. However, at 15°C the queens would take about 7 flights, compared to only about 4 flights at 24°C 21.

Unsurprisingly therefore, individual mating flights were of greater duration during warmer weather. Again the ‘best fit’ line is shown together with the variation in the primary data.

Relationship between temperature and individual mating flight duration

I found these last two graphs quite reassuring … there were lots of flights below 20°C.

Geek alert

I’m starting to get a bit obsessed with the weather here on the west coast and installed a weather station last summer. I only have complete records from July, but know we had a total of only 27 days on which the temperature exceeded 20°C from July and September.

August 2021 temperatures in Ardnamurchan

2021 was an outstanding summer here on the west coast.

Next year I’ll have data for the full queen rearing season so hope to understand this aspect of the mating biology of my queens a little better.

Conclusions

I’ve covered a lot of ground in this post … from the how far can she fly to mate? studies of the 1930’s to what appear to be short duration, and therefore relatively local, mating flights of RFID-tagged bees.

Understanding when a queen is likely to go on a mating flight should help you with timing your colony inspections. It should certainly help curb your impatience as you wait for your queens to get mated.

Finally, knowing that she can fly on much cooler days than the widely-cited 20°C gives those of us living in more northerly latitudes some reassurance that our queen rearing efforts are not entirely futile.


Notes

Some figures I meant to quote earlier; if the queen only flies between 940 m and 3.33 km to the DCA (see Duration x speed= distance above), and assuming colony densities of either 0.6/km2 or 3.2/km2 (see Apiary density about 3000 words ago 🙁 ) the number of hives ‘within mating flight range’ are between 1.7 and 111.

Quite a range, so ample opportunity for good numbers of genetically diverse drones, though remember that apiaries are not evenly distributed and DCA’s are variable distances from drone producing colonies.

Treat all of my numbers (and particularly my calculations) with considerable caution.