Category Archives: Swarm control

Queenright … or not?

A brief follow-up to the (ridiculously long) post last week about leaving queen cells in the colony after a) it swarms, or b) implementing swarm control 1.

How long does it take for the new queen to emerge, mate and start laying? 

And what if she doesn’t?

How did we get here?

We are approaching the peak of the beekeeping season. Colonies have built up strongly and should now be topped by comfortingly heavy supers of spring honey. 

Mind your back 😯 

The box you inspected in early April and found three frames of brood in is now bursting at the seams with bees and brood. Everything is getting busier and bigger. You may have already run out of supers or – lucky you – are frantically extracting to free-up supers to return to the colonies.

Depending upon your location you may already have discovered that your swarm prevention efforts, whilst temporarily effective, were soon treated with disdain as the colonies started to build queen cells.

Sealed queen cell ...

Sealed queen cell …

You are now using some form of swarm control and the colony now contains a mature queen cell.

Or they swarmed … leaving a mature queen cell 🙁

Queenless colonies

Is a colony with a charged, capped, queen cell queenless? 

A philosophical question 🙂

I guess the answer is technically no, but practically yes.

There’s clearly a queen in the hive, but she’s really a potential queen. To be useful to the colony (and the beekeeper) she has to emerge, mature, mate and start laying.

It’s at that stage that the colony can be described as queenright.

All of this takes time and all of which significantly changes the tempo of the season.

Colonies that are requeening should generally not be disturbed and the change from full-on to full-off can feel strange.

Doubly so, because the lack of reassuring inspections can make the wait seem interminable. 

It’s tempting to have a quick peek … after all, what harm could it do?

Tick tock

The development of a queen takes 16 days from egg to eclosed virgin. The first three days as an egg, then six days as a larva before a further week as a developing pupa. The rapid development is due to the very rich diet that queens are fed in the first couple of days. This triggers a host of changes in gene expression 2 which dramatically alters the morphology, behaviour and longevity of the queen from the genetically identical worker.

After a virgin queen emerges she needs to mature sexually which takes 5-6 days. During this period they don’t look or behave much like queens. They tend to be quite small and, if disturbed, rush about the frame skittishly. They are also a lot more willing to fly than a mature laying queen – you have been warned! 3

Where have all my young girls gone?

What a beauty

Virgin queens are not lavished with attention by a retinue of workers, all of which often makes them more difficult to find in the hive.

The queen goes on one or more mating flights which usually take place on warm, calm, sunny early afternoons.

She then returns to the hive and, 2-3 days later, starts laying eggs. A queen that has just started laying sometimes lays more than one egg per cell. However, she settles down fast and will usually lay in a reasonably tight pattern in the centre of one of the middle frames in the brood nest.

Have patience

Add all those timings up and you have a minimum of two weeks between the capping of the queen cell and the day when she starts laying.

To be sure, you need to know when the queen cell was capped which is difficult if you’re dealing with a colony that swarmed. Was the cell capped on the day the colony swarmed (not unusual), or was it capped during the lousy weather a few days earlier that then delayed the emergence of the swarm?

It is unwise to disturb a virgin queen.

All sorts of things can go wrong. You might inadvertently crush her during an inspection 4 or scare her into taking flight and getting lost in the long grass.

Equally calamitous would be inspecting the colony on the nice, calm, warm mid-afternoon when she decides to go off on her mating flight. She’ll be off consorting with the local drones for about 10 – 30 minutes, and may go on more than one flight on subsequent days. If she returns to find the roof and supers off, the brood frames out and smoke being puffed everywhere she may never find the hive entrance.

Inspecting a colony

None of the above ends well.

Minima and maxima

The two weeks detailed above is the absolute minimum. I don’t check these things routinely but think the only time I’ve really seen it taking that short a period (from cell sealing to a mated laying queen) is when queen rearing using mini-mating nucs.

Mini-nucs …

Queens tend to get mated in these very fast if the weather is suitable. I don’t know why 5.

But, if the weather is unsuitable, irrespective of the hive type, mating will be delayed.

By ‘unsuitable’ I mean lousy. If it’s raining persistently or blowing a hoolie the queen will not venture forth.

If it’s cool (16 – 18°C) and cloudy she might, particularly if she’s of the darker Apis mellifera mellifera strain. 

But then again, she might not 🙁 

All of which means that the two weeks quoted really is a minimum.

What if it rains for a month? The virgin queen has a ‘shelf life’. If she does not get mated within ~26-33 days of emergence she is unlikely to get successfully mated at all.

Here we go again ...

No queen mating today …

To summarise, it will take a minimum of two weeks from queen cell capping to having a laying queen in the hive. If 40 days elapse before the queen is mated (again from cell capping) it is likely that she will be a dud.

Three weeks

Assuming the weather has been OK for queen mating I usually leave a minimum of three weeks between closing the hive up with a capped queen cell and looking for the mated queen. 

There’s little to be gained by rummaging around the hive before then … and a whole lot to be potentially lost.

If you do open the hive up too early – assuming none of the nightmare scenarios above occur – what can you expect to see?

Lift the dummy board out, prise out the last frame and then split the hive somewhere in the middle of the remaining frames i.e. don’t work through frame by frame, this isn’t a routine inspection, it’s a Royal Checkup.

If you look around the middle of the face of the central frames you can often see polished cells. These have been cleaned and prepared by the workers for the queen to lay in. They’re particularly obvious if the comb is a bit old and dark – then they really do look polished and shiny.

If there are polished cells present, but no eggs, I’m then reasonably confident that there’s a queen in the hive but that she’s not started laying yet (but is probably mated).

There’s no point in looking for her. Close the hive up and leave it another week.

Brood frame with a good laying pattern

If she is laying, leave her be. Wait until she’s laid up a few frames and you can tell she has a good laying pattern of worker brood i.e. look at the appearance of the sealed brood, then find her and mark her 6.

Breathe a sigh of relief … your colony is again queenright.

Five weeks

If five weeks 7 have elapsed between leaving a freshly capped cell in the hive and the non-appearance of eggs I start to fear the worst.

The colony will now have no brood – it all emerged about two and half weeks ago – and the lack of brood pheromone means there’s a possibility that the colony will develop laying workers

Laying workers ...

Laying workers …

There may be a queen present, but she’s rapidly becoming an ageing spinster

In this situation it is probably wise to decide what Plan B is … how will you ‘rescue’ the colony?

If you leave the colony for another week or fortnight you might find a laying queen, but you probably won’t. During this period the colony will dwindle further in size and strength 8

Plan B

You effectively have four choices:

  1. Unite the colony with a known queenright colony.
  2. Requeen the colony with a mated, laying queen 9.
  3. Add a mature capped queen cell to the colony. Start nervously pacing the apiary again waiting for her to emerge, mature, mate and start laying.
  4. Allow the colony to rear their own queen by providing a frame of eggs (see below).

It is important to find and dispatch the ‘failed’ queen if you are going to do 1, 2 or 3. The queen may have failed to get mated but she might still be able to kill a challenger queen in the hive. 

Uniting the colony is often the best and safest option. It’s quick. It uses the bees remaining in the colony immediately and it strengthens another hive. It’s my preferred option … but I have quite a few colonies to work with. If you have just one (and you shouldn’t have) it’s clearly a non-starter. 

An Abelo/Swienty hybrid hive ...

An Abelo/Swienty hybrid hive …

Adding an expensive purchased mated laying queen (or a cheap one) can be risky. Terminally queenless and broodless colonies are often tricky to requeen. The most successful way I’ve found to do this 10 is to use a large cage pinned over a frame of emerging brood. And even then it doesn’t always work 🙁 

If you already have laying workers it is not worth trying to requeen the colony – they’ll almost certainly kill her. I usually try once to ‘rescue’ a laying worker hive (details here), but then shake them out.

Adding a capped queen cells can work if the colony is queenless but you will have another long wait ahead of you … and all the time the colony is dwindling in size.

She emerges into a population of geriatric workers. Far from ideal.

But what if you can’t find the queen?

Is the colony really queenless?

Perhaps she mated quite late because of poor weather and is about to get started?

Perhaps she failed to mate and is just lurking in there waiting to slaughter the £40 Buckfast queen you’re about to add 🙁 

Frame of eggs

Most of these questions can be answered by adding a ‘frame of eggs’.

A queenless colony will start to rear a new queen if presented with eggs and larvae.

A queenright colony will not.

If you are unsure whether a colony is queenright add a frame containing a good number of eggs. I usually like to use a full brood frame also containing some larvae and sealed brood. The brood pheromone will help hold back laying worker development. The new young bees that emerge will bolster the hive population and will be there to help the new queen when she returns from getting mated.

If you have the luxury of choosing a frame of eggs on relatively new fresh comb the bees will find it easier to draw queen cells. However, don’t worry if you don’t … if they’re queenless they’ll be thankful for anything.

Check the colony a few days after adding the frame of eggs. If they’ve started queen cells 11 then I just let them get on with it and check again in about a month or so for a laying queen. They won’t swarm or generate casts as – by this time – bee numbers are significantly depleted. 

However, if they don’t start queen cells it means there’s a queen somewhere in the hive. Check the other frames in the hive for eggs. It’s not at all unusual to find the original queen has now started laying. Again, leave her to get on with it.

But if there are no eggs on other frames and no queen cells (on the frame you added) you need to find the non-functioning queen … and we’ll deal with that sometime in the future 😉

Good luck


Colophon

The usual dictionary definition of queenright just references a colony of bees that contains a queen. The OED has references going back to 1911 (When a colony is found that is not queen-right, it is remorselessly broken up, and distributed among other colonies, or united with a weak colony having a good queen, C.C. Miller in Fifty Years among Bees) including some from Wedmore and E.O Wilson.  

However, none specifically state whether the queen is laying. Or what she’s laying. A queenless colony is easy to define. But what about a colony containing a virgin queen? Or a drone laying queen? 

I’d argue that in these situations the colony contains a queen, but things aren’t really ‘right’ (as in correct). In my view, queenright means a mated, laying queen. 

Please, no pedantic questions or comments about a colony containing a well mated queen that, because there’s a nectar dearth, has stopped laying … 😉

Queen cells … quantity and quality

How many queen cells should I leave in my hive?

This question pops up year after year at this time of the season.

Up and down the country we’re all busy implementing swarm control because our swarm prevention, er, didn’t 🙁

The majority of swarm control methods leave part of the colony to rear a new queen. Once she has emerged, matured, mated and proved her worth by laying up a frame or two you can then decide what to do with the old queen. 

Irrespective of the swarm control method you use – e.g. Pagden, nucleus method or a vertical split – the colony often produces quite a few queen cells. 

Similarly, if both your swarm prevention and swarm control failed and a prime swarm disappeared over the fence, there are likely to be several (or possibly lots of) queen cells left in the colony.

Queen cells – the good, the bad and the ugly

How many of these queen cells should you leave in the hive? 

Which one(s) should you leave?

Assumptions

I’m in the middle of my own swarm control at the moment and so intend to keep this relatively short and simple 1.

I am going to assume you start with one hive and you want to finish with one hive at the end of the process (i.e. you do not want to make increase). I’ll briefly mention rescuing queenless colonies and stock improvement as it’s relevant.

I’m also going to keep this as generic as possible. It’s not going to depend upon the method of swarm control employed or – with some caveats to be discussed later – whether the colony has naturally swarmed.

Here’s the starting position.

Your hive is making preparations to swarm. You apply a swarm control method that removes the old queen from the original brood box 2. This box therefore contains brood in all stages (BIAS) – eggs, larvae and sealed brood. This brood probably occupies most of the frames in the brood box. 

Also in the box are a very large number of adult bees, both workers and drones 3

And there will probably be one, several or lots of unsealed queen cells 4 present as well 🙂

Why do anything? or What’s the worst thing that could happen?

When a colony swarms naturally about 75% of the adult bees leave with the old queen. This figure is similar whether the colony is large or small. 

If you start with a large double brood colony it might contain 60,000 bees. Let’s assume a large swarm leaves as the first queen cells are capped (which is when the swarm usually scarpers).

There are still 15,000 bees and perhaps 15-18 frames of brood, several frames of which are close to emerging. The queen laying rate 3 weeks prior to the swarm was probably 1,000 to 2,000 eggs per day, meaning that number of adult workers are now emerging per day. 

Honey bee development

Honey bee development

About eight days after the queen cells were capped and the swarm left the new virgin queens emerge (see the bottom row in the picture above). By this time the worker population in the hive might well be over 20,000 again (some adult worker will have died of old age in the intervening period).

20,000 bees is more than enough to swarm again if several queens emerge 5.

These secondary swarms are called casts. They are headed by a virgin queen. They can be quite large if the original colony was very strong. 

However, with a lot of virgin queens emerging around the same time a strong colony can produce several casts, one after another. These are usually successively smaller and smaller 6. Not only are these casts too small to form an effective colony, but the originating colony can be weakened sufficiently to make its survival doubtful.

What’s the alternative?

Imagine the same double-brood colony. The old queen heads for the hills with 75% of the workforce. A week later the colony strength has been boosted by the emergence of a further 7 – 10 thousand workers … but this time there is only one capped queen cell developing.

The queen emerges.

If this queen also disappeared in a cast swarm the original colony would inevitably perish.

Why?

Because a week after the original swarm leaves there are no eggs or larvae in the colony young enough to be reared as new queens. 

She’s gone …

Swarming is reproduction of the honey bee ‘superorganism’. The survival of natural swarms is low (~25%) whereas the survival of swarmed colonies is reasonably high (>75%).

From an evolutionary perspective it makes no sense for the only queen to also leave, heading a cast swarm. The colony would have ‘traded’ a ~1:5 chance of producing two viable colonies for a 1:16 chance 7

It’s a no brainer as they say 8.

So, you can probably see where this is going now …

Swarm control

The three relatively generic and representative swarm control methods –  Pagden, a nucleus method or a vertical split – all involve manipulation of the hives one week after the initial intervention.

In the ‘classic’ Pagden method the original hive is moved from one side of the artificial swarm to the other. This has the effect of ‘bleeding off’ some of the workforce, so weakening the hive. The resulting reduced worker population often tear down all but a small number of queen cells. The reduced bee numbers also make the production of casts less likely as the colony is weaker.

Pagdens' artificial swarm ...

Pagdens’ artificial swarm …

In a vertical split the hive is reversed on the stand after 7 days, achieving exactly the same outcome on a much smaller footprint with less equipment 🙂 9

In both these methods the flying bees that have reoriented to the initial new position of the queenless hive return to find the hive moved. They then enter the nearest hive, which is the queenright component (i.e. the artificial swarm). 

I’ll get to the nucleus method in a moment.

Sometimes you will see it recommended that you also check the queenless colony at this one week timepoint to ensure that there are not large numbers of queen cells still present 10. It’s not usually necessary but – assuming you are careful – it does not cause any harm. As I explain below, it can help give you confidence.

If you don’t perform the one week hive manoeuvre you really should check for queen cells and reduce the number present.

In the nucleus method I describe the beekeeper must manage queen cell numbers in the queenless hive. Not doing so almost certainly risks losing multiple casts when the queens emerge together.

How many queen cells should you leave?

The queenless component of your swarm control only needs one queen cell

Any less than that and the colony will be non-viable without further intervention from the beekeeper.

Any more and there’s a risk that the colony will generate one or more casts. 

A very strong queenless colony with large numbers of queen cells is a recipe for disaster … or, if not a disaster, then a lot of frustration as you scurry around trying to catch the casts and/or rescue the colony from swarming itself to destruction.

Workers in very strong colonies can ‘hold back’ queens, effectively trapping them in the cell, so that emergence is more-or-less simultaneous. Should you chance to open a colony in this situation all hell breaks loose, with virgin queens dashing about all over the place.

Been there, got the T-shirt 🙂

Although entertaining – at least is retrospect – it’s better to avoid this sort of situation by restricting queen cell numbers.

All your eggs in one basket

And this is where the beginner starts to experience some trepidation.

They have to reduce queen cell numbers … to one.

That queen will head the colony for the next year or three. She’ll mother tens of thousands of workers who will make countless foraging trips and collect tens or (hopefully) hundreds of pounds of honey.

Choosing that one queen cell feels like a lot of responsibility.

The consequences of choosing a dud feel very serious indeed.

Surely leaving two or three would be a ‘safer’ bet? 

Backups, if you will … just in case the first one turns out to be a dud.

How do you know which one to pick?

Trust the bees

And this is where you need to trust the bees. They’ve been doing this pretty well for several million years.

You don’t need to choose a single egg from the thousands possibly present in the colony. The one egg that will be cared for, fed copious amounts of royal jelly and eventually emerge to head the colony.

The bees have already made those decisions 11.

They’ve started several queen cells, the majority of which are likely to be suitable. You just need to choose one of those queen cells to leave in the hive. 

It’s not a one in thousands chance of choosing a ‘winner’, it’s more like one in ten … in which any of the ten would probably be OK.

With a few caveats …

What are the features of a good queen cell?

You open the hive and find a number of sealed and unsealed queen cells.

Which to choose?

What are the features you are looking for?

What are the features you can see?

Sealed queen cell ...

Sealed queen cell …

Size, shape and appearance are the obvious ones. Position on the comb might also influence your choice.

What are the features you cannot see?

Is is a charged cell i.e. does it contain a developing pupa? Has that pupa been well fed as a larva?

Size, shape, appearance and position

Mature queen cells are large, about 3 cm long. The position on the comb – whether on the face or edge can influence the apparent size. They are generally conical, more or less evenly tapering to a neatly rounded tip. Queen cells that have been well-tended by the bees are often heavily sculpted on the outside. This is generally taken to be a “good thing”, but note that this doesn’t happen until after the queen cell is capped (see the photo above). Uncapped cells are usually smooth (see the next photo).

I think the position on the frame is irrelevant in terms of queen cell quality, but it does influence which I choose. The cell should be drawn from worker comb (!) 12 and – particularly if I’m likely to be either cutting the cell out or moving the entire frame – I like it to be in a position unlikely to get damaged as I manipulate the frames in the hive.

The edge of drawn comb, with space below and to the side, makes things easy. The central face of the comb, especially if it’s on fresh comb and not near a wire in the foundation, is also a good bet. 

The position is more important if you’re going to do something with the cell or frame other than let it emerge in situ.

Charged cells

How do you know there’s a well-fed pupa in the cell?

Ted Hooper (in his Guide to Bees and Honey) describes gently prising the cap off a sealed queen cell to check it is occupied, then re-sealing it to let development run its course. He finishes discussing how to re-seal the cell with the words “you have to do a good job or the bees will tear it down.”

I bet 😉

There are easier ways.

Firstly you can be pretty sure that any well-shaped sealed cell with a good, well sculpted appearance is likely to be occupied. Alternatively, you can identify these cells in advance and only allow those you know contain a developing larva sitting on a thick bed of royal jelly to mature.

A practical example

A few days ago I used the nucleus method for swarm control in all my colonies in one apiary. Due to work constraints and lockdown some colonies were only just starting to make preparations to swarm. None of the colonies had well developed, charged queen cells. Some had ‘play cups’ with eggs present.

Three days after making up the nucs I checked the queenless parent colonies. All had a few developing queen cells.

Here is the same photograph as above, with some cells numbered on the frame.

Queen cells – capped, open and just plain dodgy

Which do you choose?

Here is the view from below of the same frame.

Queen cells – practical example

  1. A sealed cell, perhaps a bit small 13
  2. Is a nice looking unsealed cell with a thick bed of royal jelly supporting a larva inside.
  3. Also unsealed and with a good space underneath for the cell to be drawn out as it develops.
  4. Is very similar to #2. Smooth exterior as it’s only 3 days old and unsealed.
  5. A thickened play cup from a previous season. There is no egg, larva or royal jelly inside it.

Remember that this is only 3 days after implementing swarm control.

I destroyed the sealed cell #1. Since it was already sealed it was probably made from an older larva. Cells are sealed on the eighth day after the egg is laid. Since this was only 72 hours after removing the queen the larva was probably two days old before being reared as a queen – i.e. 8 minus 3 days since queen removal minus the three days it would have already spent as an egg. Alternatively, it might have been present when I removed the queen, though I did check reasonably thoroughly.

I couldn’t be sure of the contents of this cell and I suspected that it may not have been fed on copious amounts of royal jelly during the very early days after hatching from the egg.

Cell #3 was also squidged. If you look closely from below you can clearly see the larva but no thick bed of royal jelly. I doubted it had been fed well enough in the early days. Here’s an enlargement …

Cells #1 to #4 enlarged.

Why risk it? There are better cells on the frame.

I ignored #5. It’s not a queen cell and never will be.

Uncapped cells #2 and #4 were retained. They are the right size, have a good appearance and are well placed on the frame.

I marked the top of the frame with a queen marking pen to remind me where to check, and more importantly where to be careful, when I inspect the colony a week after making up the nuc.

X marks the spot

Note that the photo above is a different hive to the numbered photo of queen cells (which I forgot to photograph).

Hold on … not so fast

Go back and look again at the numbered photo of queen cells.

There is another cell, uncapped and filled with royal jelly, to the left and a little higher than the sealed queen cell #1.

This cell is actually pretty obvious. There are relatively few bees on the frame and it is not particularly well ‘hidden’. 

Miss a couple more like that in a very strong hive and there’s a chance the colony will throw off several casts when the queen emerge. The unlabelled cell, and cells #2 and #4 are all very similar in age and appearance and would likely emerge within hours of each other.

Seven days after implementing swarm control

The hives are checked again 14.

I know which frames have good, charged developing queen cells. They are the ones that are marked. I therefore :

  • treat these frames very carefully. Do not shake the bees off the frame!
  • make sure the cells are now capped and starting to be sculpted by the bees.
  • gently inspect the remainder of the frame for other queen cells.
  • destroy any new cells that I find

I choose one of the queen cells and destroy any others on the frame. If there is more than one marked frame and I don’t need the cell for another colony (see below) then I destroy the cells on the other marked frame as well.

I then thoroughly inspect every frame in the brood box, shaking all the bees off the frames and checking for any queen cells I may have missed previously. There will be some.

All I find are destroyed.

I close the hive up and leave it undisturbed for the queen to emerge, mate and start laying. I’ll discuss this – apparently interminable – period in the future sometime.

I’m confident the cell contains a well fed pupae. It was the the bees that really selected the queen … all I did was whittle down their selection to the final choice.

Using ‘spare’ queen cells

In the photo above there are two marked frames. This is a good colony. Frugal, productive, well behaved etc. 15

There is another colony in the apiary which is poorly tempered. They are also requeening and are at the same stage.

Assuming the cells on both marked frames are good I’ll transfer one to the badly behaved colony when I conduct the seven day inspection. You can transfer the entire frame or you can gently cut the queen cell out and use it directly 16

All of the developing queen cells in the badly behaved colony will first be destroyed. Since there are no eggs or young larvae in that colony (and no queen as she was removed a week ago) they cannot rear another from their own genetic material.

The new queen will be better quality.

Similarly, you can use a ‘spare’ queen from a good hive to rescue a terminally queenless colony, or to replace an underperforming or substandard queen.

A really dodgy queen cell

I wanted to squeeze in a picture of what not to choose. 

Bride of Frankenstein queen cell

There are so many things wrong with this.

Where to start?

It’s drawn from drone comb and is not neatly tapering and conical. It’s poorly sculpted considering its age and size, which is far too big.

Whatever emerges from this cell, if anything, will not be any use to me or the bees 🙁

Seven day only inspection

The process described above involves an additional inspection 3-4 days after implementing swarm control. I think this is a modest amount of additional work for:

  • the peace of mind it gives when selecting the final cell to leave
  • the time saved when going through the colony at the seven day inspection

However, often it’s not possible. In that case I refer you back to the description of what a good sealed queen cell looks like.

Choose one of those.

Just one 😉


Notes

With gale force winds predicted for the next 2-3 days I ended up checking the ‘example’ colony (above) on day 6 after implementing swarm control measures. Here is the same frame:

Just one!

I removed two less convincing queen cells on either side of the one selected (#2 in the labelled photograph further up the page). There were a small number of queen cells elsewhere in the colony. All were removed. I’m leaving just one cell sealed, I know it contains a well fed larva. She’ll emerge in about a week and should be mated – weather permitting – a week or so after that.

And now the wait begins … 😉

 

Principles of swarm control

Having introduced swarm prevention last week it’s probably timely to now consider the basic principles of swarm control.

This is going to be relatively high level overview of why swarm control works (which it usually does if implemented properly), rather than a detailed ‘how to’ guide.

That’s because knowing what to do and when to do it is so much easier if you understand why you’re doing it.

That way, when faced with a colony clearly committed to swarming, you can manipulate the colony to avert disaster.

Which it isn’t … though losing a swarm might feel like that to a new beekeeper.

Welcome to the club

All beekeepers lose swarms, even those who rigorously and carefully employ swarm prevention methods. I lost one last year and would have lost another two were it not for a clipped queen in one 1 and some particularly unobservant and cackhanded beekeeping with another.

Mea culpa.

However, it’s called swarm prevention because it usually delays and sometimes prevents swarming.

But at some point the enthusiasm of the bees to reproduce often outstrips the possible interventions that can be applied by the beekeeper to the intact colony.

At that point, swarm control becomes necessary.

How do you know when that point has been reached?

Typically, if you carefully inspect the colony on a regular seven day cycle you will easily identify the preliminary stages of swarming. You will then have ample time to take the necessary steps to avoid losing the majority of your bees.

When is swarm control needed?

At some point in late spring 2 a colony is likely to make preparations to swarm.

Triggers for this are many and varied.

The colony may be running out of space because the foragers have backfilled the brood box with nectar during a strong spring flow.

Pheromone levels produced by the ageing queen are reducing. These usually act to suppress the formation of queen cells.

Alternatively, although mechanistically similar, the colony may be so populous that the queen mandibular pheromone concentration is – by being distributed to many more workers – effectively reduced. As described last week, in such strong colonies the queen rarely visits the bottom edges of the comb. Consequently, the levels of queen footprint pheromone – another suppressor of queen cell formation – in this region of the nest is reduced.

Whatever the trigger – and there are probably others – the colony starts producing queen cells.

Sometimes these are very obvious, decorating the lower edges of the drawn comb.

Sealed queen cells

At other times they are hidden in plain sight … in the middle of the comb, with a moving, wiggling, shifting, dancing curtain of bees covering them 3.

Queen cells ...

Queen cells …

The production of queen cells indicates that swarm prevention has not been successful and that swarm control is now needed.

More specifically, it is the production of charged queen cells with a larva sitting in a deep bed of Royal Jelly, that indicates prompt swarm control is required.

Charged queen cell ...

Charged queen cell …

And remember, there may well be more than one queen cell and they are not always on the same frame.

Unsealed and sealed queen cells

With experience you can ‘age’ queen cells by their size and appearance. The larva in the queen cell in the photo above hatched from the egg about 3-4 days ago.

When the larva is five days old the cell will be sealed and the larva pupates 4.

Queen development

Queen development …

In a further 8 days i.e. 16 days after the egg was originally laid in the cell, the new virgin queen will emerge.

But the colony will have already swarmed.

That is because, under normal circumstances, a colony usually swarms on the day that the queen cell is sealed

There are two events that often delay swarming beyond the day that the queen cell is sealed.

The first you have no control over. It’s the weather. Colonies usually swarm on lovely warm, sunny days. If it’s cold and wet, or blowin’ a hoolie, the swarm will wisely wait for a day with better weather. Wouldn’t you?

If you have a week of poor weather in mid/late May (the peak swarming season around here at least) then the first day of good weather is often chaos with swarms all over the place 🙂

Swarmtastic!

The second thing that delays swarming is if the old queen has a clipped wing. In this instance the swarm usually waits until the new queen emerges before trying to leaving the colony.

The other event, less routine in my experience, that stops swarming 5 is supercedure. In this, the queen is replaced in situ, without the colony swarming. Queen cells are still produced, usually rather few in number 6. I’ll discuss supercedure at some point in the future.

Destroying queen cells is not swarm control

If you simply destroy developing queen cells the colony will eventually swarm.

Either you’ll miss a queen cell – and they can be very hard to spot in a busy colony – or the bees will start one from an older larva and the colony will swarm before your next 7 day inspection.

Beekeeping is full of uncertainties. That’s why these pages are littered with caveats or adverbs like ‘usually’. However, ‘the colony will eventually swarm’ needs no such qualification. If all you do is knock back queen cells you will lose a swarm. 

I said in the opening section that losing a swarm is not a disaster, though it might feel that way to a beginner.

In reality, for a beekeeper who thinks destroying queen cells is a form of swarm control, losing a swarm can be a disaster 7.

When is ‘not a disaster’ actually a disaster?

Here’s the scenario … on one of your regular inspections (delayed a week because of a long weekend in Rome 8) you open the hive and find half a dozen fat, sealed queen cells decorating the lower edges of a couple of frames.

Using your trusty hive tool you swiftly obliterate them.

Job done 😀

But wait … under normal circumstances when does the colony usually swarm?

On the day the queen cell is sealed.

That colony had already swarmed 😥 

She’s gone …

What’s more, it may well have swarmed several days ago. Therefore there will no longer be any eggs or very young larvae in the hive that could be reared as new queens. Without acquiring a new queen (or a frame of eggs and young larvae) from elsewhere that colony is doomed 😥

So … repeat after medestroying queen cells is not swarm control.

If they are sealed, the colony has probably swarmed already and destroying all that are there jeopardises the viability of the colony.

If they are not sealed, then destroying them will not stop them making more and you will miss one tucked away in the corner of a frame.

And the colony will swarm anyway.

Generally, destroying all the queen cells in a colony is a lose-lose situation 🙁

The principles of swarm control

Disappointingly, almost none of the above has been about the principles of swarm control 9. However, the point I make about colony viability allows me to get back on topic in a rather contrived manner 😉

When a colony swarms, ~75% of the adult bees and the mated, laying queen fly away.

They leave behind a much depleted hive containing lots of stores, some sealed brood, some larvae, some eggs and one or more sealed queen cells.

Swarming is colony reproduction. Therefore, both the swarm and the swarmed colony (the bits that are left behind) have the potential to form a new fully viable colony.

The swarm needs to find a new nest site, draw comb, lay eggs and rear foragers. The swarmed colony needs to let the new queen(s) emerge, for one queen to get mated and return to the hive and start laying eggs.

A small swarm

A small swarm …

But importantly these events take time. Therefore, neither the swarm nor the swarmed colony are likely to swarm again in the same season.

And that, in a nutshell, describes the two defining features of many types of swarm control:

  • the colony is manipulated in a way to retain its potential to form a viable colony
  • the colony is unlikely to swarm again until the following season

So, which parts of the hive population have the potential to form a viable colony?

The bees in the colony

A colony contains a mated, laying queen. The thousands of eggs she lays are part of the developing workforce of larvae and pupae, all of which are cared for by the very youngest adult workers in the hive, the nurse bees. Finally, the third component of the colony are the so-called flying bees 10, the foragers responsible for collecting pollen and nectar.

The principles of swarm control

Of those three components – the queen, flying bees, and the combination of developing bees and nurse bees – only the latter has the potential to form a new colony alone. 

The queen cannot, she needs worker bees to do all the work for her.

The flying bees cannot as they’re unmated and cannot therefore lay fertilised eggs.

But if the combination of nurse bees and developing brood contains either eggs or very young larvae they do have the potential to rear a new queen and so create a viable colony.

Furthermore, thanks to their flexible temporal polyethism 11 the combination of the queen and the flying bees also has the potential to create a viable colony.

Divide and conquer

The general principle of many swarm control methods 12 is therefore to divide the colony into two viable parts:

  1. The queen and flying bees – recapitulating, though not entirely, the swarm 13. We’ll call this the artificial swarm.
  2. The developing brood and nurse bees. This component must contain eggs and/or very young larvae from which a new queen can be reared 14. We’ll call this the artificially swarmed colony.

I’ve described two very standard swarm control methods in detail that fit this general principle.

  • The Pagden artificial swarm, probably the standard method taught to beginners up and down the country. 
  • The vertical split, which is a less resource-intensive variant but involves more heavy lifting.

Both initially separate the queen on a single frame and then exploit the exquisite homing ability of the flying bees to separate them from the nurse bees/brood combination that have been moved a short distance away. 

Both methods are effective. Neither is foolproof. 

The artificially swarmed colony almost always raises multiple new queen cells once it realises that the original queen has gone. If the initial colony was very strong there’s a good chance several queens will emerge and that the colony will produce casts – swarms headed by virgin queens.

To avoid this situation (which resembles natural cast production by very strong colonies) a second move of the artificially swarmed colony is often used to reduce further the number of flying bees 15, and so weaken the colony sufficiently that they only produce a single queen.

Alternatively, the beekeeper does this manually, by removing all but one queen cell in the artificially swarmed colony

And the nucleus method?

Astute readers will realise that the nucleus method of swarm control is similar but different.

Here's one I prepared earlier

Here’s one I prepared earlier

It separates the colony into two viable parts but there is no attempt to separate the majority of the flying bees from the brood/nurse bees.

I like the nucleus method of swarm control. It’s easy to understand, very simple to implement and – done properly – very effective.

In particular, I think it is an easier method for beginners to grasp … in a “remove the queen and the colony cannot swarm” sort of way 16.

However, the queenless part of the split colony is inevitably left relatively strong, with brood, nurse bees and a lot of the flying bees. As a consequence there’s a good chance it will produce cast swarms if it’s allowed to rear multiple queens to maturity.

Which is why you must inspect the queenless part of the split colony one week later. As I said in my original post on this method:

The timing and thoroughness of this inspection is important. Don’t do it earlier. Or later. Don’t rush it and don’t leave more than one queen cell.

Which neatly introduces nucleus colonies which is the topic for next week 😉


 

2019 in retrospect

The winter solstice, the shortest day of the year, is tomorrow. It will be a long time until there’s any active beekeeping, but at least the days are getting longer again 🙂 

The queens in your colonies will soon – or may already – be laying again.

What better time to look back over the past season? How did the bees do? How did you do as a beekeeper? What could be done better next time?

Were there any catastrophic errors that really must not be repeated?

Overview of the season

Overall, in my part of Scotland, it was about average.

But that, of course, obscures all sorts of detail.

Spring was warm and swarming started early. I hived my first swarm before the end of April and my last in early July. This is about twice the length of the usual swarming season I’ve come to expect in Scotland. However, it wasn’t all frantic swarm management as there was a prolonged ‘June gap’ during which colonies were much more subdued.

The summer nectar, particularly the lime, was helped by some rain, but the season was effectively over by mid-August. I don’t take my colonies to the heather. Overall, the honey crop was 50-60% that of the (exceptional) 2018 season.

Looking at the yields from different apiaries for spring and summer it’s clear that – despite the warm spring – colonies did less well on the early season nectar (~40% that of 2018). I suspect this is due to their being less oil seed rape (OSR) grown within range of my apiaries. The colonies were strong, but the OSR just wasn’t close enough to be fully exploited..

Over recent years the area of OSR grown has reduced, a trend that is likely to continue.

Winter oil seed rape – the potential is not obvious

The winter rape is already sitting soggily in the fields; I’ve chatted to a couple of the local farmers and will move some hives onto these fields if colonies are strong enough and the weather looks promising.

Bait hives

Every year I’ve been back in Scotland I’ve put a bait hive in the garden.

Every year it has attracted a swarm.

This year – with the extended swarming season – it led to the capture of three swarms in about 10 days. As the June gap ended the weather got quite hot and sultry 1 and the first swarm arrived near the end of that month.

One week after the first swarm arrived there was lots more scout bee activity. There were also quite a few dead or dying bees littering the ground underneath the bait hive. It turned out that these were the walking wounded (or worse) scout bees from two different hives fighting.

Gone but not forgotten

Within 48 hours another swarm arrived and I was fortunate enough to watch it descend.

Incoming!

I moved the hive that evening, placing another bait hive on the same spot. By the following morning there were yet more scout bees checking the entrance and a third swarm – by far the biggest of the three – arrived later that day.

Each was a prime swarm and none were from my own hives which are in the only apiary 2 within a mile of the bait hive.

Watching the scout bees check out a bait hive is always interesting. There’s a fuller account of the observations and lessons learnt – of which there were several – written in the post titled BOGOF (buy one get one free 😉 ).

Swarm prevention

My swarm prevention this year either used the nucleus method or vertical splits (with an occasional Demaree for good measure) for most hives. All prevented the loss of swarms and queen mating went about as well – or badly – as it usually does i.e. never as fast as I’d like, but (eventually) all were successful.

Split board

Split board …

I did miss a couple of swarms. One relocated underneath the OMF of the hive it originated from because the queen was clipped and, having fallen ignominiously to the ground, she just clambered up the hive stand again.

The second swarm was also not lost as I inadvertently trapped the queen on the wrong side of the queen excluder. D’oh! In my defence, I’ve had a rather busy year at work 3 and it’s little short of a miracle that I got any beekeeping – let alone swarm control – done at all.

Mites

Considering the extended June gap, which resulted in a brood break for some colonies, mite levels were appreciably higher this year than last. I think this can largely be attributed to the warm Spring which allowed colonies to build up fast. Several colonies were strong enough to swarm in late April.

I do a limited amount of mite counting during the season but also monitor virus loads in emerging bees in our research colonies. In most colonies these stayed resolutely low and no production colonies needed any mid-season interventions for mite control.

Poly Varroa tray from Thorne's Everynuc with visible mites.

Gotcha! …

Newly-arrived swarms were treated as were some broodless splits. The former because many swarms carry a larger than expected mite population 4 and the latter because it’s an ideal opportunity to target mites as – in the absence of brood – all will be phoretic.

All colonies were treated with Apivar immediately after the summer honey came off. At the same time they were fed copious amount of fondant in preparation for the winter ahead.

In late November most colonies were broodless and were treated with a vaporised OA-containing miticide.

What worked well

In what was a pretty tough year for non-beekeeping reasons even small beekeeping successes have assumed a significance out of all proportion to the effort expended on them.

In my first year or two of beekeeping honey extraction was an unbridled pleasure. As hive numbers increased it because more of a chore. An electric extractor marginally improved things.

However, there was still the never-ending juggling of frames trying to balance the extractor and jiggling of the unbalanced machine as it sashayed across the floor.

Rubber-wheeled castor with brake

Two years ago I purchased some rubber braked wheels to add to the extractor legs.

This year I finally got round to fitting them.

The jiggle-free revolutions were a revelation 🙂

I know some beekeepers who stand their extractors on foam pads. Others who have them bolted to a triangular wooden platform. I can’t imagine either solution works better than these castors, which also make moving the extractor to and from storage much easier.

I changed my hive numbering system this season. I’d previously referred to hives by position or with a number written on the box. This caused some issues with the (sometimes shambolic) way I do my beekeeping.

If the hive moves and it’s numbered by position then its number should change. Manageable, but a bit of a pain.

If the position does not change but they’re expanded from a nuc to a full brood box do they get a new number or retain the old one? A problem if it’s written on the box.

And what happens when you move queens about in the apiary (which we sometimes need to do for work)?

Numbers for hives and queens

Numbers for hives and queens

All hives and queens were assigned a number – small red discs for the queen and big, bold numbers for the box. They stay with the colony or the queen … and the records 😉

This has worked very well. As colonies expand the numbers move, if queens are moved I know from and to where (and keep a separate record of queen performance). When colonies are united the queenless component loses both the queen number and the colony number.

The numbering has been a great success. The numbers themselves less so. Most of the red discs have faded very badly and a few of the hive numbers have cracked and/or blown away.

Numbered nuc and production colonies.

Never mind … the system works as intended and it has significantly improved my record keeping. I now know which hive and queen I’m referring to 😉

The Apiarist in 2019

I might squeeze in a more thorough overview of funny search terms and page accesses before the New Year. Briefly … there are significantly more subscribers and an increase of ~20% in overall page reads.

This year marks the sixth full season of The Apiarist which still surprises me. There still seem to be things to write about. Post length continues to increase, though the overall number of posts remain almost exactly one a week. Amazingly I’ve written nearly 95,000 words this year.

Words, words, words …

We had some server issues but most of these appear to have been resolved. Spam remains a problem and the machine auto-filters several hundred messages a day to keep my inbox only unmanageably overflowing. It has meant I’ve had to add some “I am not a robot” CAPTCHA trickery to the contact and/or comment forms. I’m aware that this has caused some problems making contact but can’t find an alternative solution that doesn’t swamp me in adverts for fake sunglasses, Bitcoins or Russian brides.

I live in Scotland and have no use for any of these things 😉 5

The year ahead

There are three main items on the ‘to do’ list for 2020 6.

The first is to start queen rearing again. Pressure of work has prevented this from happening over the last couple of seasons and I’m missing both the huge satisfaction it brings and the improved control over stock improvement. I’ve done lots of queen rearing in the past, but work has muscled its way in to too many weekends and evenings recently 7.

3 day old QCs ...

3 day old QCs …

I now have some perfectly adequate bees.

Actually, although they’re far from ‘perfect’ they are also far better than ‘adequate’.

I’ve got a couple of lines that have too much chalkbrood and almost all of them are less stable on the comb than I’d like. They don’t fall in wriggling gloops off the corner of the frame as some do, but they’re more active than I’d prefer. It’s a trait that has crept into some stocks over the last couple of years and I need to try and get rid of it.

The second is to provide better information on the provenance of my honey to potential and actual purchasers. There’s increasing interest in sourcing high quality local food and, as I’ve discussed recently on honey pricing, we should be aiming to provide a premium product (at a premium price 😉 ). The public are also increasingly aware that some of the major supermarkets have been reported to be selling adulterated honey. Providing details of the batch, the apiary and the area in which it was produced should help define it as a quality local product.

And generate repeat business.

Local honey

Finally, I’m planting up a new apiary on the west coast with dozens of pollen-bearing trees before I start beekeeping there. This has been a long and protracted process as it has involved clearing large areas of invasive rhododendron. The first 125+ native trees go in this winter – a mix of alder, loads of willow, hazel, blackthorn and wild cherry. More will follow if I manage to stop the deer eating them all.

Only another few acres of rhododendron to clear 🙁

The new apiary is in a Varroa-free region so I will not be moving my current bees there, but instead sourcing them from other areas fortunate enough to be mite-free. This is a long-term project.

Bee shed #3 … bigger and better.

The trees will need a few years to mature but the bee shed (bigger than all that have gone before 🙂 ) foundations are finished and the shed will be assembled sometime in March.

Holibobs

The holiday period is almost here. Many beekeepers will be thinking about fondant top-ups and oxalic acid mite treatment. I’ve done the latter already and – if your colonies are also broodless – hope you’ve done the same. All my hives remain reassuringly heavy but as the weather warms and brood rearing gears up I’ll have some fondant ready ‘just in case’.

I’ve covered last-minute beekeeping gifts in previous years. I think the (digital edition) American Bee Journal remains good value and provides a different perspective for UK beekeepers of what happens in the US.

And with that I’ll pour another glass of mead red wine 8 and wish you all Happy Christmas/Holidays (delete as appropriate).

David


 

Window of opportunity

I’ve recently discussed problems faced by beekeepers trying to control high Varroa levels in colonies during the ‘body’ of the beekeeping season. Essentially the problems are two-fold:

  • Many miticides need to be used for several weeks to target mites in capped cells.
  • The soft or hard chemicals used for Varroa control are – with the exception of the formic acid in MAQS – incompatible with honey production.

This type of midseason mite management should not be needed if parasite levels are controlled in late summer and midwinter.

If it is needed it suggests that the treatment(s) failed or that mites are being acquired through robbing or drifting from other colonies in the neighbourhood (either your own, a nearby apiary or a feral colony).

Opportunity knocks

However, all is not lost. Most seasons offer at least one opportunity to intervene and control mite levels.

Knowing when and how to exploit it requires an appreciation of the development cycle of the bee.

Honey bee development

Honey bee development

The important numbers are the 21 and 24 day development cycle of workers and drones respectively, the 16 day development cycle of the queen and the time it takes for eggs to hatch, grow as larvae and pupate in capped cells.

Not shown is the maturation period after emergence for the queen (5 to 6 days) before she goes on a mating flight, or the delay after returning before she starts laying (2-3 days) 1.

Swarms

The easiest scenario to discuss is when the colony swarms.

Consider the swarm first. A prime swarm is broodless, contains a mated queen and ~35% of the mites that were present in the issuing colony. All the mites will be phoretic. Assuming there’s drawn comb available the queen will start laying soon after the swarm is hived (or conveniently moves into your bait hive).

Eight days later the first eggs will have hatched, the larvae grown and the brood will be capped.

At which point the majority of the mites will start to become inaccessible again.

However, during those 8 days it’s ‘open season’ for those phoretic mites.

It is sensible to quarantine swarms from an unknown source and treat for mites in the first 8 days if needed.

If the swarm is a cast with an unmated queen you’ve got a bit more time. The virgin queen needs to get out and mate, mature and start laying. This tends to happen in just a few days if the weather is accommodating, so don’t leave things too long.

The swarmed colony

Now consider what’s left in the colony that swarmed 2. There will be sealed and unsealed brood and – notwithstanding the reduced egg laying by the queen as she’s slimmed down in preparation for swarming – there are also likely to be some eggs.

There will also be a sealed queen cell (and, in a strong colony, several sealed and unsealed queen cells).

Queen cells ...

Queen cells …

Without intervention the queen(s) will start emerging about 9 days later. If you intervene, knocking down all the sealed cells and leaving just one good charged open cell 3, it will be a couple more days before the queen emerges.

Weather permitting it will be a further 8 days before the newly mated queen starts laying. In reality, this is the absolute minimum and is rarely achieved in a full hive 4.

Simultaneously, in the requeening hive, the open brood is maturing and being capped and the capped brood is emerging (releasing more mites).

About eight days after the swarm leaves all the worker brood in the hive will be capped.

Twenty one (or 24 in the case of drone brood) days after the last egg was laid by the queen all the brood will have emerged.

Consequently all the mites in the colony will be phoretic.

The window of opportunity

So, if you need to treat 5 the window of opportunity is between the last of the brood from the old queen emerging and the first of the larvae from the new queen being capped.

You can determine when this is likely to be based upon the known activities of the old and new queen during the swarming period.

The window of opportunity

The diagram above makes a number of assumptions. As presented, all minimise the duration of the minimum broodless period:

  • The old queen continues laying until the day she swarms
  • The colony swarms on the day the queen cell is sealed
  • The beekeeper does not intervene to leave an open, charged cell of a known age
  • The new queen takes the minimum amount of time to mature, go on a mating flight and start laying

It should be self-evident that more realistic timings applied to these will only increase the length of the minimum broodless period.

For example, the weather will have a significant impact. Swarming may be delayed due to adverse conditions. During this time the slimmed-down queen will probably lay very few eggs.

Similarly, only 8 days are shown for maturing, mating and starting to lay. Mating flights are very weather-dependent and this period could easily take a week longer (or more).

Splits and artificial swarms

If you practice swarm control using the nucleus method, vertical splits or the classic Pagden artificial swarm the same types of calculations apply.

These three methods all share two features:

  • They involve the physical separation of the box with the old queen and the new developing queen
  • The old queen is isolated with a very small amount of brood – either open brood or emerging brood

The queenright component of the split (whether nuc box or new brood box left on the old site) will follow the right hand part of the diagram above i.e. everything to the right of the vertical red line labelled laying. Here it is expanded a bit:

Queenright splits and the window(s) of opportunity

The queen should start laying almost immediately if drawn comb is provided meaning this new brood will be sealed in a further 8-9 days. The timing and duration of the minimum broodless period depends upon whether you prime the queenright split with a small amount of open or emerging brood.

  • Open brood will be capped within about 6 days of the eggs hatching. If the frame contains nothing older than 3rd instar larvae (about mid-size) you will only have about 3 days before the cells are capped – indicated by bracketed region labelled (A) above, with capped pupae shown by the dark shaded arrow.
  • Emerging brood offers a bit more flexibility. If all the brood emerges in the first 2-3 days after the split (shown with the pale shaded arrow) then the duration of the broodless period, shown in (B) above, lasts about 5 days.

Queenless colonies after splitting

The queenless part of the split will behave like the swarmed colony in the upper line diagram. All capped worker brood will have emerged 21 days after the split (drones after 24 days).

Capped brood arising from eggs laid by the new queen in this colony will depend upon the origin of the queen.

If the colony is left to rear its own queen then the timing will be similar to the upper line diagram plus the additional time required to create a capped queen cell (which rather depends upon the state of the colony when split).

However, if you add a mature queen cell a day off emergence you will reduce the time to the appearance of new capped brood by ~8 days. Consequently the colony will probably never go through a phase with no capped brood present. This is the same, but even more so, if you requeen the colony with a mated queen.

The miticide of choice

Of all the (rather limited range of) miticides available, an oxalic acid-containing treatment is the most appropriate. Oxalic acid (OA) is well-tolerated and, if used on a colony that lacks capped brood, over 90% effective. In addition, and critical for treatment in a narrow window of opportunity, only one treatment is required.

OA can be administered by trickling or sublimation. I’ve covered both methods in detail previously so won’t repeat what’s required, or the recipes, here.

Note that in many cases although the colony will have no capped brood it will not be broodless. For example, larvae from eggs laid by the new queen will be present but uncapped.

This is important because trickled oxalic acid-containing treatments are toxic to open brood. Under these conditions the treatment of choice would be sublimated oxalic acid.

Sublimox vaporiser

Sublimox vaporiser …

Finally, note that if you are going to sublimate Api-Bioxal you’ll either have to spend ages cleaning the pan of the vaporiser, or line it with aluminium foil in advance.

The treatments outlined here are not intended for routine use. They should be used only if needed based upon mite counts or overt signs of DWV-mediated disease.

However, if you do need to treat make sure you do it when the treatment will be most effective.


 

Natural vs. artificial swarms

I’ve now covered four of the most frequently used swarm control strategies. These are:

  • Pagden’s artificial swarm – the horizontal splitting of the colony
  • The vertical split – an equipment-frugal variant of the above involving a vertical separation of the colony
  • The nucleus method – in which the queen is removed with sufficient workers to make up a small (nuc) colony, leaving the original colony to rear another queen
  • The Demaree method – which, at its simplest, relocates the queen from the brood and associated nurse bees, but does not physically split the colony

If conducted correctly all should prevent loss of a swarm. However, the individual methods – even the first three which involve the physical separation of the bees in the hive – are not the same.

In addition, these swarm control methods do not recapitulate the separation of bees that occurs when a hive naturally swarms.

The purpose of this post is to contrast the original and new colony composition of the split-based methods of swarm control (i.e. Pagden and vertical) with natural swarms.

Temporal polyethism

I introduced this term when discussing the honey bee colony as a superorganism. It means that adult worker bees have different roles depending upon their age. For the first two and a bit weeks they have duties inside the hive such as cell cleaning, brood rearing and wax production.

They then transition through a period of being guard bees before becoming foragers, flying from the hive and collecting water, nectar and pollen.

For convenience I’ll refer to these two groups of bees as young, nurse or hive bees and flying bees.

Vertical and horizontal splits

The classic Pagden artificial swarm and the vertical split are fundamentally the same process.

If unsealed queen cells are found during a colony inspection the queen, with a frame of emerging brood, is moved to a new box. This box is placed on the site of the original hive.

The remaining bees and brood are moved, either to one side in the case of the Pagden or on top of the queen-containing box (separated by a split board) in a vertical split.

Split board ...

Split board …

Critically, the new box with the brood and bees is provided with a new hive entrance, located off to one side or on the opposite side of the original hive 1.

Flying home

Over the following day or two the flying bees leave the relocated brood box with the new entrance and return to the queen-containing brood box in the original location.

As a consequence of their excellent homing navigational skill, the hive manipulation results in the separation of the bees into two populations:

  1. The flying bees i.e. those over ~3 weeks of age that had orientated to the original hive location, which are now located with the queen.
  2. The nurse bees i.e. those less than 3 weeks old, which remain in the relocated brood box, together with the brood in all stages (eggs, larvae and pupae).

Artificial swarm separation of the colony

Artificial swarm separation of the colony

How does the artificial swarm compare with the age distribution of bees in a real swarm?

Real swarms

I’ve previously discussed prime swarms and casts. The former contain a mated queen. In contrast, casts are produced from very strong colonies after the prime swarm has left. Casts are headed by a virgin queen. These are sometimes called after swarms and are usually smaller than prime swarms.

What about the workers in the swarm? What might be expected?

Perhaps they’re primarily the older flying bees? After all, these are the bees that have finished their hive duties and are now routinely foraging outside the hive. It’s the natural place for them.

Swarm of bees

Swarm of bees

Alternatively, remember that swarms have no ‘homing’ instinct for a day or two after emerging. They can be readily moved and you can safely ignore the less than three feet or more than three miles rule. Perhaps this means that they’re primarily young bees that have yet to go on their orientation flights?

Real experiments and contradictory results

Enough speculation … how do you determine this experimentally?

There have been numerous studies of the age distribution of bees in natural swarms. However, the data tends to be rather contradictory though the methods used are often broadly similar.

How do you determine the age composition of workers in a swarm?

Essentially you ‘spike’ the colony with a set number of marked bees of a known age over about 8 weeks. This is easy to do, but tedious.

Workers are allowed to emerge in an incubator. On the day of emergence (0 days old) they are marked with a colour that distinguishes them from older or younger bees. Every three days 100 identically marked i.e. same age, bees are added to the study hive(s). Over the period May to July this will accumulate red, then yellow, then blue, then mauve, then cyan, then pink etc. cohorts of workers, each representing a known age class.

It must be a nightmare spotting the queen in these hives 😉

The colony is allowed to swarm, the swarm collected and the number of bees of the different age cohorts in the swarm counted.

I missed a step out there. Have you ever tried counting the bees in a swarm? It’s much easier if they don’t move.

1002, 1003, 1004, 1005, er, where was I? Damn!

1002, 1003, 1004, 1005, er, where was I? Damn!

Perhaps it’s best that I missed that step out 🙁

What you end up with is a count of the total number of bees in the swarm and the numbers of bees of each 3 day cohort over the last several weeks. You can therefore determine the age distribution of the workers in the swarm.

Is it as simple as that?

I’ve actually oversimplified things a bit. There’s a possibility that different age cohorts of bees die within the hive at different rates, perhaps depending upon forage availability or weather or something else.

Think about it. Assume there was a dearth of nectar in late May and the blue and red labelled cohorts added during that period were underfed and died prematurely.

If there were very low numbers of blue and red bees in the swarm you might assume that these ages were ‘left behind’ by the swarm … when actually they weren’t able to swarm at all.

The real question is therefore whether the age distribution of bees in the swarm is similar to that in the parental hive.

OK, OK … is it?

No.

Swarms do contain bees of all ages.

However there are significantly more young bees and many fewer old bees than would be expected from the age distribution of workers in the parental colony.

Age distribution of bees in swarms

Age distribution of bees in swarms

The o and e in the graph above represents the position of the observed and expected median age class for the expected distributions. So, in swarm C the observed median age is ~10 days old, whereas the originating hive median age was ~19 days.

The graph above comes from a 1998 study by David Gilley 2 and supports earlier work 3 by Colin Butler 4 which is often cited as one of the definitive studies on the ages of bees in a swarm.

Additional considerations

Is it surprising that young bees predominate in natural swarms?

Swarms usually emerge from the hive late morning or early afternoon on warm, sunny days. In fact, at exactly the time most older bees aren’t in the hive anyway because they’re out and about foraging.

Remember also that swarming is a precarious activity for the colony. Most swarms do not survive 5. Natural selection will have resulted in swarm populations that maximise their chance of survival.

Once bees start foraging their life expectancy is pretty short. It has been estimated that they experience about 10% mortality per day. If only old bees left in the swarm with the queen the newly established colony would very rapidly dwindle in size, perhaps before significant numbers of new brood emerged (which takes 21 days from the first egg being laid). This would likely limit the chances of survival of the new colony.

What has this got to do with artificial swarms?

As beekeepers (or at least as responsible beekeepers) we spend May and June rushing about like headless chickens trying to control swarming in our bees.

Many of us achieve this using a variety of methods which are generically referred to as artificial swarms. I suspect that many beekeepers think that the artificiality is because of our interventions.

Where have all my young girls gone?

Where have all my young girls gone?

It is … but it’s worth remembering that the artificial swarms we generate are very different in composition to natural swarms. Our artificial swarms predominantly leave the older bees associating with the queen, with the young bees remaining with the brood.

These old bees have to draw new comb and rear the new brood. These are activities they last did weeks ago (a long time in the life of a bee).

Final thoughts

There are artificial swarm control methods that were developed to better replicate the age distribution of bees in a natural swarm. One example of these is use of a Taranov board. I’ll cover this in a future post.

It’s also worth noting that the bees of different ages in a natural swarm have different roles even before they occupy a new location. The older bees form a mantle around the bivouacked swarm that protects it from inclement weather (amongst other things) and the oldest bees are the scouts responsible for finding a new nest site.

Again, both topics for another post … I’ve got bait hives to set out 🙂


 

Demaree swarm control

I’ve covered three swarm control methods in previous posts. These are the classic Pagden artificial swarm, the vertical split that is directly comparable but requires less equipment and more lifting, and the nucleus method.

As described on this site, if successful, all achieve the same two things:

  • They prevent a swarm being lost. Don’t underestimate how important this is in terms of not irritating your neighbours, in helping your honey production and in giving you a quiet sense of satisfaction 🙂
  • They result in the generation of a second colony headed by a newly mated queen.

This doubling in colony number, or – more generally – the managed reproduction of colony numbers, is termed making increase.

Managed reproduction

Making increase is of fundamental importance in beekeeping.

Without deliberately splitting colonies, unless you buy in nucs every year (kerrching!), collect swarms or steal hives 1 your colony numbers would never increase.

Making increase is therefore critical if you want more colonies. However, it’s just as important (and a darn sight less expensive than buying nucs) if you want to make up any overwintering colony losses, thereby keeping the same number of colonies overall 2.

Not making increase

Once you’ve got bees, with good management, you can always have bees. However, at some point you reach that sweet spot where you have enough bees and don’t want more colonies.

The Goldilocks Principle is the concept of having just the right amount. Not so few colonies that a really harsh winter causes problems, and not so many that you cannot enjoy your beekeeping at the peak of the season.

When you reach that point you no longer need to make increase, you just want to keep the same number of colonies.

Which means that the swarm control methods that essentially reproduce the colony may not be ideal.

Of course, you can unite colonies having removed the unwanted queen from one of them, but this is additional work. Not a huge amount of work admittedly, but work nevertheless 3.

This is where the Demaree method of swarm control comes in useful. As practised, Demaree swarm control prevents the loss of the swarm without increasing colony numbers.

It has the additional significant advantages of keeping the entire foraging force of the colony together (even better for honey production than not losing a swarm) and needing no specialised equipment.

Demaree swarm control – in principle

George Demaree

George Demaree

The principle of the method is very straightforward.

When queen cells are found during an inspection you conduct a form of a vertical split, separating the original queen and flying bees from the nurse bees and sealed brood. You place the latter above a queen excluder.

A few days later you return and remove any new queen cells from the top box, so preventing swarming. Finally you leave all the brood to emerge from the top box.

Demaree swarm control – in practice

A cartoon diagram of the process is shown below. The only additional equipment required is a brood box with 11 frames of drawn comb or foundation and a queen excluder.

That’s it.

Demaree swarm control

Demaree swarm control

Here’s a bit more detail:

  1. If you find queen cells during an inspection gently remove the brood box and place it on an upturned roof off to one side 4.
  2. Place the new brood box on the original floor. Add 9 frames of drawn comb or foundation, leaving a gap in the middle of the box.
  3. Using minimal smoke, go through the original box and find the queen.
  4. Place the frame with the queen in the middle of the new brood box on the original floor. This frame must contain no queen cells.
  5. Push the frames in the new brood box together and add in the eleventh frame.
  6. Add a queen excluder.
  7. Add the supers above the queen excluder. If there were no supers on the original hive then it’s worth adding a couple of supers now. It will provide better separation of the new and old brood boxes and it will encourage the bees to store nectar in supers rather than the top brood box.
  8. Add a second queen excluder.
  9. Place the original brood box on top of the queen excluder.
  10. Go through the upper brood box and remove every queen cell. Shake the bees off the frames to do this. Push the frames together and add one additional frame. Add the crownboard and roof.

Leave the colony for one week. At the next inspection you should only need to check the top brood box (i.e. the original one).

  1. Carefully inspect every frame and remove every queen cell. Again, you should shake the bees off the frames to do this. If you miss any queen cells there’s a good chance the colony will swarm.
  2. Close up the hive and leave the brood in the top box to emerge.
  3. About 25 days after conducting the first inspection (1 above, where you first found QC’s) you can remove the upper brood box from which all brood will have now emerged.

Explanatory notes

If you have a reasonable understanding of the development cycle of queen and worker bees you will understand how the Demaree Method simultaneously prevents swarming and keeps the entire colony together.

Honey bee development

Honey bee development

  • By splitting the colony you separate the queen and the flying bees from the nurse bees and the brood. The queen in the new (now bottom) box has ample space to lay, particularly if you provide her with some drawn comb to use.
  • The bottom box will now be less crowded and the swarming urge will therefore be much reduced.
  • You destroy all of the queen cells in the original (now top) box when you rearrange the hive. This is to stop any new queens emerging in this box in the following week.
  • However, this top box still contains eggs and young larvae. Since it is now located a long way from the queenright box the level of queen pheromone is very low. Consequently, in the week following the hive rearrangement, the bees will create new emergency queen cells in the top box.
  • When you return a week later all the eggs in the top box will have hatched and the youngest larvae left will be about four days old i.e. too old to be reared as new queens. Therefore, when you destroy all the new queen cells in the top box, you prevent the colony swarming.
  • You can remove the top brood box as soon as all the brood has emerged i.e. 25 days after first rearranging the hive 5.

Demaree pros and cons

Pros

  • An effective method of swarm control
  • Relatively simple procedure to implement and understand
  • Only requires a single brood box, frames and a queen excluder
  • Generates big, strong colonies and keeps the entire foraging force together
  • Modifications of the process can be used for queen rearing 6

Cons

  • Necessary to find the queen
  • Critical to remove all queen cells at the start and after one week
  • Generates tall stacked boxes, so some heavy lifting may be involved
  • Drones in the top box get trapped by the queen excluder 7
  • In a strong flow the bees can backfill the top box with nectar. Add sufficient supers when you first rearrange the hive

Framed wire QE ...

Framed wire QE …

Historical notes

George Whitfield Demaree (1832–1915) was a lawyer in Kentucky, USA, and a pioneer in swarm control methods. His eponymous method was published in the American Bee Journal in 1892. The original method was subtly different from that described above:

Demaree method

Demaree method

In his description he emphasises the need to keep the colony together to maximise honey production.

I suspect Demaree used a single sized box (as broods and supers) as he describes placing brood frames above the queen excluder in the centre of the super flanked by empty frames. As described, he doesn’t mention returning after one week to destroy queen cells above the queen excluder. Don’t forget to do this!

I particularly like Demaree’s comment that any swarm prevention method that “require a divided condition of the colony, using two or more hives, is not worthy of a thought”.


 

The nucleus method

Almost all beekeeping associations – and most books – teach Pagdens’ artificial swarm as the recommended method of swarm control. It is tried and tested and reasonably dependable. However it can be a bit tricky to grasp for inexperienced beekeepers.

At least part of the problem is you have two hives that look the same, one on the original site, one adjacent. Conducted properly, the adjacent hive is moved to the other side of the original a week or so into the process.

Teaching this in a poorly lit, draughty church hall in late January, facing the audience with the inevitable confusion over left and right, and getting ‘new’ and ‘old’ hives mixed up, often bamboozles the beginner 1. Or the instructor 😉

Here’s an alternative … the nucleus method of swarm control.

There she goes ...

There she goes …

General principles

This method is simplicity itself. When the colony looks as though it’s preparing to swarm you remove the queen, some stores and some bees into a nucleus hive.

This keeps the queen safe in case things go awry with the original colony.

You then return a week later and remove all but one queen cell in the original colony. The virgin queen emerges, mates, returns and starts laying.

A month or so after starting the original colony is headed by a new queen and you have a ‘spare’ building up in the nucleus box. You can overwinter this, sell it, give it away or – after removing the queen – unite it back with the original hive.

And that’s it … I said it was simple 🙂

Here is a more complete account.

Equipment needed

It goes without saying that the nucleus method of swarm control needs a nucleus (nuc) hive 2. Any sort of 5 frame nuc is suitable. Nucs are incredibly useful, so they are a good investment. If you’re buying one for the first time get polystyrene as they’re lighter, better insulated and much better for overwintering bees in. I’ve reviewed poly nucs a few years ago. There are even more makes to choose from now.

I’d recommend not using a two frame nuc as there’s not really enough room for stores and colony expansion 3.

Two frame nuc box

Two frame nuc box … a bit too small for the nucleus method of swarm control (but usable at a pinch)

In addition to the nuc you’ll need five frames that are compatible with your nuc and hive. Ideally, one or two of these should be drawn comb, but don’t worry if you just have foundation. A dummy board can also be useful. Like nucs, you can almost never have too many dummy boards.

Honey bee development

To properly understand honey bee swarm control you really need to understand the timing of the development cycle of queen bees.

Honey bee development

Honey bee development

Queen cells have a characteristic appearance. Unlike the horizontally-oriented worker cells, larvae destined to become queens hatch from eggs laid in vertically-oriented queen cells. After three days as eggs and a further five days of larval development the queen cell is sealed.

A colony will usually swarm on or soon after 4 the queen cells are sealed.

~3 day old queen cell ...

~3 day old queen cell …

This is why it is recommended that colony inspections are conducted at seven day intervals. If the colony is thinking of swarming you’ll find an unsealed cell (because there were none last week when you inspected and they take 8 days to be sealed) and you can immediately start swarm control.

Day 1 – Making up the queenright nucleus colony

If you find one or more unsealed queen cells at a routine inspection … don’t panic. You’re prepared, you’ve done your homework and you have the necessary equipment.

  1. Stuff the entrance of a nucleus hive with grass and place it near the colony 5.
  2. Remove one of the outer frames from the colony (you’ve probably already done this to give yourself room for the inspection) as this should have a good amounts of sealed and unsealed stores.
  3. Check again that the queen isn’t on this frame of stores (unlikely) and that it doesn’t contain any queen cells (again unlikely).
  4. Gently transfer the frame of stores plus all the adhering bees to the nucleus box.
  5. Continue the inspection and find the queen. Be gentle, don’t rush, don’t use too much smoke.
  6. Ideally you want the queen on a frame with some sealed and emerging brood. If you are lucky you’ll find her on a suitable frame.
  7. Gently transfer the queen and the frame she is on to the nucleus box. It is very important that this frame has no queen cells on it. Check very carefully. Destroy any you find.
  8. Your nuc colony is now queenright and has two frames of bees. Push the frames against the side wall of the nuc box, leaving a wide gap.
  9. Into this gap shake a further two frames of bees. Foragers are likely to leave the nuc and return to the original hive. You do not want the box to be short of young bees. If in doubt shake a further frame of bees into the gap in the nuc 6.
  10. Add a frame of drawn comb if you have it then fill the box with foundation. Add a dummy board if needed. Gently place the crownboard and roof on the nuc, secure everything with a strap and turn your attention to the colony.

Notes

  • The purpose of this exercise is to establish a small colony with stores, a laying queen, space to lay and sufficient bees to support her and the brood being reared. Remember stores, queen, bees, space and no queen cells you won’t go wrong.
  • You will usually find the queen on a frame with eggs and young larvae. It’s very important that this frame does not have any queen cells on it.
  • Ideally you want the queen on a frame of emerging brood. This offers a number of advantages
    • The young bees will immediately strengthen the population supporting the queen
    • The vacated cells can be used by the queen to lay eggs (so reducing the need for drawn comb, or for the bees to build new comb)
    • The nuc colony will go through a period with no sealed brood and you can take advantage of this for Varroa management if needed (I’ll deal with this in another post)
    • It’s unlikely (due to the age of the other brood) to have a queen cell on it
  • One of the most common problems encountered with this method of swarm control is making up (or ending up) with a nuc that is not strong enough. A weak nuc will be unable to defend itself against robbing or wasps. There’s very little chance of weakening the original hive too much.
  • One way to avoid losing foragers from the nuc is to move it to an out apiary more than 3 miles from the original hive.
  • If you do leave the nuc in the same apiary check it a couple of days later. The bees should have chewed their way out through the dried grass. If they haven’t, pull a bit out at the corner of the entrance to encourage them to fly.

Day 1 – Preparing with the queenless colony

  1. Inspect every frame in the colony. Destroy all large queen cells 7. Anything that looks like the queen cell in the picture above should be destroyed. The idea here is to only leave queen cells containing very small larvae.
  2. Mark the frames containing these remaining selected queen cells using a drawing pin or pen.
  3. Push the frames together, add two frames of foundation, add the crownboard and close up the colony.

Here's one I prepared earlier

Here’s one I prepared earlier

One week later – Ensuring the queenless colony does not swarm

The timing and thoroughness of this inspection is important. Don’t do it earlier. Or later. Don’t rush it and don’t leave more than one queen cell.

  1. Inspect the colony and look for queen cells on the frames you marked a week earlier. These had very young larvae in them then and so will now be sealed 8.
  2. Select one queen cell to keep. Just one. Which one? Choose one that is large, well-shaped and has a sculptured exterior.
  3. Destroy all the other queen cells on this frame. All of them! If you need to remove the bees to see the frame better either brush them off gently or blow gently on them. Do not shake the bees off the frame as this might damage the developing queen.
  4. Gently return the frame with the selected queen cell to the box.
  5. Inspect all other frames in the colony (not just the ones you marked last week) and destroy all of the queen cells you find.
  6. You can shake the bees off these other frames to be sure of finding all other queen cells.
  7. Remember that some queen cells will be unsealed 9 … destroy them all.
  8. Return all the frames to the colony. Close it up and leave it for at least two weeks before inspecting again (see below).

Sealed queen cell ...

Sealed queen cell …

Notes

  • The purpose of this return visit is to leave the colony with only a single queen cell.
  • Because you removed the queen a week ago there are no other suitably aged young larvae or eggs for the colony to rear queens from. Therefore, the colony cannot produce multiple casts (swarms headed by virgin queens).
  • The nucleus method of swarm control often leaves the queenless colony very strong 10, if you leave more than one queen cell the colony may produce casts.
  • What if the queen gets lost on a mating flight? Shouldn’t I leave two queen cells? Just to be on the safe side? No. If there’s a problem with the queen getting mated you’ve still got the old queen tucked away safely in the nuc box.
  • Queen cells that are large, well shaped and sculptured have received a lot of attention from the workers and so presumably contain a well-fed and good quality queen 11.
  • Don’t be tempted to inspect the colony in less than two weeks. Ideally leave them for three weeks. If you inspect too early there’s a chance that the queen may not have had a chance to mate and start laying (so the point of inspecting is missed) or – worse – that she returns from her mating flight as you have the box open and is then confused or lost.
  • Don’t meddle! Look for pollen being taken into the colony.
  • Have patience. Bees have been around for a few million years. They would not be this successful if they weren’t pretty good at getting queens mated …
  • Finally, particularly if the weather is poor, check the nuc as well. Ensure that it has sufficient stores. With reduced numbers of bees there’s a chance they could starve if the bees cannot forage (in which case the queen in the main colony is going to struggle to get out and mate as well).

Everynuc

Everynuc …

Pros and cons of the nucleus method of swarm control

With the exception of vertical splits almost all of my swarm control uses this nucleus method 12. I particularly like the nucleus method because I have lots of nuc boxes ( 🙂 ) and because it leaves manageable single-entrance hives rather than double height, multiple entrance stacks.

Almost all of the foraging bees are left with the original colony so the nectar-gathering capacity is not significantly reduced.

I almost never use the Pagden artificial swarm, largely because it ties up too much equipment.

Pros

  1. Limited amount of extra equipment needed – five frames and a nuc box … both of which are useful anyway.
  2. The old queen is kept safe and out of the way.
  3. Simple to implement, with just two visits at fixed times.
  4. Reasonably easy to understand the manipulations involved.
  5. No heavy lifting.
  6. You generate a nucleus colony to give away or to build up for overwintering.

Cons

  1. You need to find the queen.
  2. You need to find all the queen cells and use your judgement as to their age and quality.
  3. Unless you remove the nuc to an out apiary there’s a good chance lots of the bees will return to the original hive. Make sure you add enough at the start and be prepared to add more if you check the nuc after a day or two and find it heavily depleted.
  4. If you don’t want to make increase the nuc is a little more difficult to unite back with the original colony 13.

Give it a go … what could possibly go wrong?


 

Superorganism potential

The term superorganism can be used to refer to a colony of honey bees. The term gained prominence in the mid/late noughties having been reintroduced by the world-renowned myrmecologist 1 E.O. Wilson.

Bees, like ants (myrmex, “ant”, from the Greek μύρμηξ), are social insects in which there are divisions of labour. Different individuals within the colony perform different tasks. Some of these roles are defined by the castes in the colony – queen, worker and drone in a colony of honey bees for example – and some are defined by physiological differences between individual members of the same caste.

The term superorganism describes the entirety of the colony and is defined as a group or association of organisms which behaves in some respect like a single organism.

Essentially, a superorganism has characteristics and behaviours that the individuals within the colony – due to caste or physiological specialisation – do not exhibit.

The superorganism operates as a unified entity, collectively working together to maintain and reproduce the colony.

Division of labour and temporal polyethism

Drones and queens have relatively straightforward roles in the colony. Drones, like teenage boys, lounge around eating and thinking about sex. The queens are egg-laying machines.

An egg laying machine

An egg laying machine

Although there’s undoubtedly work involved in laying your bodyweight in eggs at the height of the season, the real work in the colony is – appropriately – done by the workers.

Worker bees exhibit temporal polyethism i.e. they display different patterns of behaviour depending upon their age. They have a maturational schedule in which they sequentially undertake age-correlated roles in the colony:

  • Young bees work in the hive in a series of roles starting with cell cleaning (days 1-2), nursing developing larvae (nurse bees; days 3-11) and wax production (days 12-17).
  • After two to three weeks the workers undergo significant physiological changes (weight loss, changes in immune function, reduced stress resistance) which prepare them for a productive life outside the hive. During this period the bees transition through a period when they act as guard bees.
  • Older bees (the ‘flying’ bees) perform a range of foraging activities including water carrying, pollen collection and nectar gathering.

And then they die in the field 🙁

Behavioural plasticity

This behavioural maturation is controlled by a so-called negative feedback loop between vitellogenin (Vg 2) and juvenile hormone (JH).

Nurse bees have high Vg levels which are reduced at the transition to foraging. Conversely JH levels increase with the onset of foraging (I know this sounds counterintuitive). These changes are responsible for a range of physiological changes in the worker bee.

Behavioural maturation in worker bees

Behavioural maturation in worker bees

But it’s not as simple as that. High Vg levels can block JH synthesis, so delaying maturation and foraging. Similarly, JH may reciprocally inhibit Vg synthesis and induce early foraging.

Clearly that last couple of sentences indicates that worker maturation is not an invariant process. It doesn’t always occur after 2-3 weeks.

In fact, the maturation or ageing process in honey bees is a very interesting phenomenon.

Ageing exhibits seasonal variability and remarkable plasticity.

Nurse bees can survive for at least 130 days and overwintering bees may survive up to 280 days. Clearly ageing in bees is a remarkably variable process. Overwintering bees ‘mature’ into either nurse bees or foragers. Presumably this has evolved as an effective mechanism of allowing spring colony build up (by having sufficient bees for the different roles) once environmental conditions improve.

In addition, there is another striking feature of the maturation process of honey bees.

Under certain social environmental conditions maturation is reversible.

This reversible maturation can be demonstrated by removing the nurse bees from the hive. Under these conditions some of the younger foragers revert, both behaviourally and physiologically, to nursing tasks. JH levels drop and Vg levels increase.

Old foragers are unable to undergo this rejuvenation.

Reversible maturation in worker bees

Reversible maturation in worker bees

Which finally and in a round the houses way gets me to the subject I meant to cover in the first place this week …

Brood and the superorganism

The honey bee colony superorganism not only contains a queen, workers and drones. It also contains brood. In the following text I’ll use the term brood as a collective noun meaning all the eggs, unsealed larvae and sealed pupae in the colony (unless otherwise specified).

Is the brood a component of the superorganism?

It certainly is.

Laying workers ...

Laying workers …

Remember previous discussion of laying workers. These are workers that lay unfertilised eggs which develop into drones. Egg laying by workers is suppressed by pheromones produced from unsealed brood 3. Therefore brood does influence the behaviour of the colony 4.

If the complete colony – brood, workers, drones and a queen – is a superorganism, which components of the colony, individually or together, have the potential to form the superorganism?

And why should this matter?

Swarming and the superorganism

During swarming, either naturally during colony reproduction, or during manipulation by the beekeeper, the ‘superorganism’ is broken up.

During natural swarming the (old) mated queen leaves the colony with 60-75% of the workers to establish a new colony. By the time the swarm leaves, the original colony – which has all the eggs, larvae and brood (obviously) – is usually already well on the way to rearing a new queen. The (new) virgin queen emerges, gets mated, and the colony has successfully reproduced.

Many of the colony manipulation methods that are used to prevent the loss of natural swarms exploit the potential of the components in the colony to form a complete new colony.

Most ‘artificial swarms’ work by breaking the colony – the superorganism – into two parts:

  1. The queen and the ‘flying’ bees. Even young bees can fly, so the term ‘flying’ bees refers to the older bees from the colony that have matured sufficiently to leave the hive.
  2. The nurse bees and all the brood.

Swarms, splits and superorganisms

Swarms, splits and superorganisms

These two parts both have the potential to create a new colony.

The queen and the flying bees that form the swarm (or the queenright part of an artificial swarm) occupy a new site (or hive 5), draw comb in which the queen lays, the larvae are fed 6, pupate and emerge. At the same time, foragers collect the necessary nectar and pollen to maintain the new colony.

The swarmed colony (i.e. the queenless part of an artificial swarm) contains ample stores and the nurse bees. What they don’t have is a queen. But they do have eggs and young larvae. The nurse bees select and feed one or more of these young larvae with copious amounts of Royal Jelly. A few days later a virgin queen emerges, matures, mates and returns to the colony to start laying eggs.

Sealed queen cell ...

Sealed queen cell …

Therefore both natural and artificial swarms exploit the potential in both parts of the original colony to eventually reproduce the colony.

No potential

Not all components of the colony have the potential to give rise to a new colony or superorganism. A solitary queen doesn’t even have the ability to feed herself properly, let alone double up for egg laying and nursing larvae duties.

This comes as a surprise to some people. If you frequent any of the online discussion forums you’ll sometime see questions posted like this:

What sort of hive do I need to buy to put a queen bee in to make honey?

Followed by some polite, or not so polite, responses saying that there’s a little bit more to beekeeping than that 7.

The ‘flying’ bees alone, in the absence of a queen, also have no potential. They can lay eggs (as laying workers, see above), but since the eggs are unfertilised the colony will be doomed. It’s not unusual for a queen from an artificial swarm (or from a cast) to fail to return from a mating flight, so condemning the workers in the hive to oblivion.

Swarms and behavioural plasticity

The classic artificial swarm involves moving the nurse bees and the brood to a new site, leaving the queen and the flying bees in the original location.

You do this so that the flying bees that have orientated to the position of the original hive – whether out in the field actively foraging or in the moved hive – eventually return and so become separated from the nurse bees and the brood.

In doing this you remove the urge to swarm and you weaken the queenless hive.

The majority of those flying bees are foragers.

And this is where behavioural plasticity is essential. remember that the artificial swarm predominantly contains foragers, not the nurse bees needed to feed developing larvae.

Some of these foragers undergo rejuvenation to produce wax or to become nurse bees. These build new comb and, in a few days, feed larvae that have hatched from the eggs laid by the queen.

This behavioural plasticity contributes to the potential of the artificial swarm to produce a new colony or superorganism.

A small swarm ...

A small swarm …

Do the same processes happen in natural swarms?

That requires a discussion of the worker composition of swarms which is not straightforward and will have to wait for another day 😉


 

Taking stock

It’s the middle of the season 1. Hopefully, the timely application of swarm control measures such as a vertical split or Pagden’s artificial swarm, have maintained strong colonies and created additional colonies headed by new queens.

July is the month I review my stocks with the goal of:

  • replacing ageing queens that are unproductive
  • removing bad tempered colonies (though most have already been dealt with)
  • preparing strong colonies to exploit late season nectar flows
  • making up nucleus colonies for overwintering, either as backups or for sale

Of course, this type of taking stock should be a continuous process through the season, but it’s easier to start it now for the winter, rather than leaving it to the shorter days, more variable weather and less dependable nectar flows of late summer.

Two into one does go

A small hole ...

A small hole …

Often the intention is to simply replace an old queen with a new queen. In a vertical split this is simplicity itself. Remove the queen that is unwanted and the split board, replacing the latter with a sheet of newspaper. Make one or two very small holes in the newspaper with the point of a hive tool and leave the colony to it.

Over the course of the next few days the workers will chew through the newspaper, unite amicably and set about building up the stores for winter.

A week or so after uniting I rearrange the frames, usually making space for the queen to lay in the top box with the brood below. If the colonies being united are smaller it’s sometimes possible to remove one box altogether.

There’s discussion online about quick ways to unite colonies by spraying both with air freshener. The smell – which is usually pretty awful 2 – masks the colony scent and so the colony does not fight. I’ve not done this so can’t recommend it (or, for that matter, criticise it).

Since I’ll be returning a week later to check the boxes and rearrange frames I’m happy to stick with newspaper uniting which rarely fails. Air freshener is also one less thing to carry in the bee bag.

Nucs for pleasure and profit

Five frame nucleus (nuc) colonies overwinter well if prepared properly 3. They are really useful in the early spring to make up for any winter losses, to replace colonies with failing queens 4 or to sell.

Everynuc

Everynuc …

Overwintered nucs are often appreciably more expensive than those imported later in the season, or in the glut of bees that follows the swarming season.

The queen has proved herself and the nuc is available when demand is highest … at the very beginning of the season.

Whilst I would – and have – argued that it might be better to start beekeeping later in the season working alongside your mentor, there are strong economic imperatives to overwinter nucs for sale.

Splits and nucs

With a successful split (or Pagden) you now have two queens, one strong colony and one building up fast. The latter – with the new queen – can be used to prepare a nuc for overwintering, with the remaining bees and brood strengthening the original colony for the late season nectar flow 5.

It’s easy to prepare a nuc colony to take away to a distant apiary – the new queen, a frame of stores, one or two of emerging brood and a mixed frame of eggs and brood, all with the adhering bees, together with a couple more frames of bees shaken in over the top. Make up to five frames with foundation, seal them up and ship ’em off to your out apiary.

If you don’t have access to an out apiary you should ensure that the majority of the older workers are omitted when preparing the nuc, and you should add in additional young bees to help the new queen get established.

It’s also worth stuffing the nuc entrance with dead grass for a few days to enforce the ‘new environment’ on the bees.

Stuffed

Stuffed …

You exclude the old foragers by giving each frame placed in the nuc a gentle shake before putting it into the box. The old bees fly off, the young ones cling on. Do the same with the ~3-4 additional frames of bees added on top before re-siting the the nuc in the apiary.

Nucs may need feeding, particularly if there’s a dearth of nectar or bad weather. Keep an eye on them. By excluding the old foragers you can feed them without the risk of robbing. However, it’s wise not to feed them for the best part of a week after making up the nuc to allow any carried-over stragglers to return. This is why it’s important to include a full frame of stores from the outset.

Variations

There’s still ample time in the season to rear new queens, so all sorts of other combinations of requeening/uniting and/or splits are still possible. For example, I’ve recently used a particular queen to requeen a colony and will split the box she came from into 2-3 nucs, all of which should build up well for overwintering.

By splitting the box after the new queen cells are raised I ensure they were produced by a well-balanced population of bees, with ample stores under ideal conditions. I think this is better than divvying up the frames from the recently queenless box and hoping to achieve the strong and balanced population in all the nucs. Inevitably some are stronger than others … or, more significantly in terms of queen cell production, weaker.

And in between all of this amateur dabbling I’ve been working with our friends and collaborators in Aberdeen on methods of Varroa control to minimise the levels of deformed wing virus (DWV) as well as starting our studies on chronic bee paralysis virus (CBPV) …

Hot day, hard work ...

Hot day, hard work …

… oh yes, and moving into a new house 😉 6