Category Archives: Swarm control

Pagdens’ artificial swarm

Every beekeeping association that runs a winter course for beginners will teach swarm control. In almost every case they use the artificial swarm method that evolved from that promoted by James Pagden (1814-1878). So universal is this teaching that the terms ‘Pagden’ and ‘artificial swarm’ are used almost interchangeably.

Swarm control – defined below – is an important skill in beekeeping. It saves your bees from bothering the neighbours and by not losing swarms you increase your honey crop. Furthermore, understanding the principles may help apply some related queen rearing techniques.

I’m planning a few posts on swarm control this season and realised I’d never described the ‘classic’ artificial swarm – possibly because I don’t often use it. To avoid referencing other sites with more or less comprehensive (or correct) descriptions I’ve catalogued the ‘bare bones’ of the process here.

Swarm control

A small swarm

A small swarm …

Swarm control and prevention are two different things. The latter are the steps taken to stop a colony from ‘thinking’ about swarming, e.g. young queens and ample space. In contrast, swarm control are what is needed once there are signs that swarming by the colony is imminent. The most common sign is the discovery of unsealed, charged (i.e. occupied) queen cells during an inspection. You practise swarm prevention to prevent, or at least delay, the need for swarm control. Once swarm control is needed many beekeepers use Pagdens’ artificial swarm.

If you discover sealed queen cells during an inspection there’s a good chance your swarm prevention didn’t work and that it’s too late for swarm control. Colonies with unclipped queens usually swarm when the developing queen cells are capped. If there are sealed queen cells and no sign of the queen or eggs then they’re probably hanging in a tree or occupying a bait hive by now.

The artificial swarm

Pagdens' artificial swarm ...

Pagdens’ artificial swarm …

The principle of the artificial swarm is to separate the queen and flying bees from the brood and nurse bees. This is achieved by a couple of simple colony manipulations. These exploit the tendency of flying bees to return to the location of the hive they were reared in, or more accurately, the location of the hive from which they took their orientation flights. If you remember this it all makes sense.

The diagram is colour coded. The original hive location is the centreline of the image. The old hive is mid-grey, the new hive is light-grey. Brood-containing frames are red, foundation or drawn comb is black. The queen is indicated Q (black if mated, white if a virgin or recently mated). The timings of the manipulations are indicated.

Day 0 and Day 1

Don't panic

Don’t panic …

During a routine inspection of a strong colony anytime from mid-April to late June (depending upon the season) you discover unsealed, charged queen cells. Don’t panic. Collect the necessary equipment for an artificial swarm – a complete new hive consisting of a floor, brood box and full complement of frames (preferably some or all are drawn comb, the rest can be just foundation – or foundationless frames), a crownboard and a roof. An additional hive stand is also useful, though not essential.

In the diagram I’ve assumed that it takes a day to collect this lot and get back to the apiary … whatever, once you’re ready, proceed as follows.

  1. Move the old hive a couple of metres away from the original location. If there are supers present remove these and the queen excluder first, putting them aside.
  2. Place the new floor and filled brood box on the original site, with the entrance facing the same way as before.
  3. Remove two frames from the centre of the new brood box.
  4. Gently go through the old hive. Find a frame of open brood. Shake the frame gently to dislodge the flying bees, inspect it carefully, place the queen onto the frame and put it into the centre of the new brood box. There must be no queen cells on this frame.  Push together the adjacent frames and add a spare frame so the hive is full.
  5. If there were supers present at the start place them on the new hive above the queen excluder. If there were no supers you might need to feed this colony some thin syrup to encourage them to draw new comb.
  6. Add the crownboard and roof to the new hive.
  7. Push together the frames in the old hive, add one more frame, put the crownboard and roof back and leave them to get on with things.

What does this first manipulation achieve?

At the end of this first manipulation you’ve manually separated the queen from almost all the brood and nurse bees. The queen is in the original location in the new hive. All the flying bees will return to the original location – because that’s where they first orientated to – over the next day or so. This new hive is viable as it contains a mated queen, bees to support her and lots of empty space for her to lay in.

The old hive is also viable, but only of they first rear a new queen. Since there are open queen cells present these must be sealed to allow pupation and metamorphosis which takes 7 days.

Day 7

Move the old hive to the opposite side of the new hive. A couple of metres away is fine. Flying bees that have matured in the old hive during the preceding week will find the hive missing when they return from foraging. They’ll most likely enter the hive closest to the hive they flew from, which is the one with the queen in it i.e. the new hive on the original hive stand. This boosts the strength of the queenright colony. More importantly, it depletes the old hive of bees, making it less likely that they’ll throw off a cast if more than one virgin emerges§.

It’s important that the old hive is not interfered with after the first 7 days. There will be a new virgin queen present who will be going out on mating flights a few days after emergence. Leave this hive untouched for at least another fortnight. In the diagram above the black frame in the old hive indicates that the oldest brood is emerging, leaving plenty of young bees to tend to the newly mated queen and ample space for her to lay in due course.

Day 21+

The old hive should now contain a newly mated and laying queen. Inspections of this colony can start again. The new colony – on the original site – should be building up well.

If you want to increase your colony numbers (make increase), you’ve done so. If you don’t want to make increase then the two colonies can be united over newspaper. Remove the old queen first, either terminally (!) or by giving her to another beekeeper.


I tend to prefer a vertical split for two reasons – it uses less equipment and it takes up less space. However, the underlying principles of the two processes are very similar as will be discussed in a future post.

 Day 0 and Day 1 can be done on the same day. I’ve separated them on the assumption that you’re as badly prepared as I am and don’t have piles of spare equipment waiting to be used in the apiary. The only thing to be sure of is not to let the queen cells be capped. If necessary knock back all the visible queen cells … once they’ve decided to swarm they will start more.

 I can never write those words without hearing them uttered in the voice of Lance Corporal Jones from the sitcom Dad’s Army. Since this was broadcast between 1968 and 1977 writing that last sentence makes me feel rather old.

§ I’m trying to steer well clear of the thorny problem of how many queen cells to leave in the old hive. That’s a separate topic in its own right. Some suggest letting the bees decide (i.e. do nothing), others leave one or two.

Queen clipping – why?

I sometimes have colonies in my (very) small suburban garden … it’s great to be able to watch the bees before leaving for the lab or to observe them early in the season bringing in pollen from the crocuses. It’s also a convenient staging post between my out apiaries and a whole lot easier than carrying heavy boxes around through waist-high field margins. However, I’m aware that my neighbours may not share my enthusiasm for bees. I therefore do my utmost to only keep well-behaved colonies in the garden by selecting for docility as a priority when queen rearing. In addition, I make sure any queens heading colonies in the garden are clipped. Queen clipping is the trimming of one wing, preventing the queen from flying any distance should the colony swarm. In the absence of a queen, a prime swarm leaving the hive will either return to the hive or will cluster with the queen a very short distance from the hive.

Clipped queen ...

Clipped queen …

A colony in the garden swarmed on open queen cells (QC) last Sunday afternoon. The colony had chosen to ignore the super, so filled the brood box with nectar (I suspect I’d added the super too late and the colony had already started to think about swarming). Consequently the colony ran out of space. The QC’s were about 3-4 days old and unsealed. There’d been none present at the previous inspection (remember that colonies usually swarm once the first QC’s are sealed). The colony was half-way through a vertical split (to be described in the future) with the original queen in the top box and the newly emerged virgin in the bottom box. I’d been away and arrived home to find the top box swarming and the air filled with bees. With an unclipped queen they would usually settle in a nearby tree or bush and then send out scouts to find more desirable accommodation.

I might have been fortunate enough to catch this, but they might have settled somewhere inconvenient like the chimney or on the kids trampoline in the garden next door. However, because the queen was clipped, she couldn’t fly and the bees just milled about for 15 minutes … a fantastic sight and sound. Eventually they returned to the hive … but to the bottom box. Shortly after they’d settled I found the queen and a small retinue of workers on the ground about a metre from the hive entrance (see photo above). I quickly went through the top box, shaking bees off the frames and knocked off all the QC’s. I also swapped out a couple of nectar-filled frames for drawn comb. I then ran the queen back into the entrance. With luck the reduced density of bees and increased space to lay will discourage them from swarming again*.

A queen with a clipped wing generally swarms later than an unclipped queen, potentially giving you a few extra days between inspections. However, as the example above shows, you can’t rely on this so seven day intervals between inspections are still recommended. Had I not found the queen she would have probably crawled back to the hive stand, climbed up the leg and ended up under the open mesh floor. Although this is not ideal, it provides another opportunity to recapture her and it’s far preferable to losing the bees altogether or bothering your neighbours with swarms.

Summer storm ...

Summer storm …

Although the weather was wonderful when the colony swarmed, it rapidly changed later in the afternoon when we were treated to downpour of biblical proportions … any swarm caught out in the torrential rain and hail would have probably fared very badly.

Time to close the hive up ...

Time to close the hive up …

The image above (the densest cloud formed a wide band from the North East to the South West, almost directly above three of my apiaries) is a composite of three images stitched together in Photoshop. I was desperately trying to get through the last few hive inspections but had to abandon things and seek shelter in the car. The rain and hail didn’t last long, but what it lacked in duration it more than compensated for in volume (both sound and fluid ounces).

Perhaps surprisingly, in the 30 minutes or so before the heavens opened the bees were remarkably well behaved.

* Update on checking six days later (today) the blue marked and clipped queen is back and laying again in the top box. It looks like she’s been getting a lot of attention as the blue paint has almost disappeared. There are no signs of any more queen cells but they’re still not taking much notice of the super. Unfortunately, they are showing signs of robbing another colony in the garden, so I’ll shortly be moving them to another apiary.

In the meantime, I prepared a stack of boxes in preparation of moving house and – within 24 hours – another swarm moved in. I’d missed a finger-wide gap in the stack and the bees occupied a chest-high pile of broods and supers. These look like another generous donation from a neighbour … thank you.

Brace yourself

My favoured swarm control involves using the Demaree method, a vertical split of the queen and foragers to the lower brood box, leaving the brood and nurse bees above the queen excluder. After three weeks all the brood in the upper box will have emerged and the box needs to be removed – either to melt out the wax from old comb, or to reuse the drawn comb. If you don’t remove the upper brood box the bees will fill it with nectar if there’s any sort of flow.

Brace comb on underside of clearer board

Brace comb on underside of clearer board

Rather than shake bees out I use a clearer board under the upper brood box when I want to remove it. This only needs to be in place overnight to work. The picture above shows what happens if you fail to remove it during a good flow. Five days later the space is filled with brace comb packed with nectar. The top bars of the upper super were welded firmly to the underside of the clear board.

What a mess

What a mess

This is what happens when work gets in the way of beekeeping.