You could write a book on the subject of ‘how to handle swarm season’, and several people have. In the one thousand or so words allotted to this blog post, I shall therefore have to miss out quite a bit. Nevertheless, given the popularity of this subject and the time of year, I shall dive in.
Am I already too late?
I haven’t looked at the data, but many people are saying that this has been a cold spring. Obviously, location plays a considerable role here, and I’m going to concentrate on my bees in my area, which is basically a load of apiaries surrounding Manchester Airport. Recently, I checked on a friend’s bees (to help her introduce a new queen) and in one hive I found that they had already swarmed. She had not inspected that colony yet due to the cold weather. I found a very ripe queen cell and released the virgin queen, then got rid of the other cells. Lesson: it’s worth inspecting your colonies before May, regardless of the weather, because occasionally, they swarm early.
The space race
Many of my colonies went into winter with a super of partially capped honey beneath the brood box. If the super isn’t right for extracting, I stick it on the floor, knowing that the bees will move honey upstairs near the brood to use it as winter stores. These are Langstroth hives. Sometime in March, I reversed the boxes, moving the brood box to the floor with a now empty super overhead. You could add a queen excluder between the two, but I often don’t. This is a good plan for strong colonies, but a terrible one if they are weak. For smaller colonies I just remove the super, or sometimes put them into a poly nuc, or even shake them out; it depends on how small they are.
For other hives that went into winter in single brood boxes, the supers started going on as and when they were needed. The earliest was late February (that hive is now a double brood with three supers) but mostly supers started going on from late March/early April. I don’t care so much about the weather; I’m looking at how much space the bees have and whether they are expanding. Some need space, some don’t. Some require less space – they typically turn out to be rubbish, but every so often I’m a softy and give them a chance.
Drawn comb and excluders
Some bees are more prone to swarming than others, but if they feel cramped for space in the run-up to swarm season, many of them will start to make queen cells. Supers of drawn comb count as space, but frequently foundation frames are ignored. This makes life tricky for beginners, who may only have foundation frames. Giving a super of foundation in March/April is not likely to have the desired effect; they may make a mess of the foundation and swarm anyway. Supers that were extracted the previous season are what the bees like.
I flip-flop about queen excluders. Not just queen excluders, sadly. My current approach has been to add supers of drawn comb without an excluder. The queen can lay where she wants (often in the supers) but as a nectar flow kicks in, and more supers are added, the brood nest moves lower down. After the May flow, I will put the queen in the bottom box and put an excluder overhead. The supers will then be just for honey, once any brood has emerged. If I add a super of foundation, it will usually be above an excluder.
Inspection regime
As evidenced by the aforementioned lost swarm, once we get to late April, in my area, I have to make sure I inspect my colonies every week or so. These can be rapid checks to make sure that the bees have space, stores, a laying queen (I just look for eggs) and no queen cells. As colonies grow they make more cups, then some have eggs in them, and then jelly and a small larva.
If I find cells in a more advanced stage, either sealed or nearly so, I have some work to do. The big question is, have they already swarmed? Normally, if cells are sealed, and I can’t find eggs, I have to accept that they have gone. However, if I find eggs, then the queen is usually in there somewhere. If they have swarmed, I leave one ‘nearly sealed’ cell which has a juicy larva in it, and destroy all other cells. I may re-queen later in the season, but for now, I let them make a new one.
Splits and equalisation
When I find super-strong colonies with loads of brood early in the season, I now tend to remove 1, 2 or 3 frames of sealed brood, depending on how ridiculously strong they are. The removed frames are replaced with foundation to give the bees something to work on, and they soon draw out the wax and use it for more brood. The result is that a hive which would probably have thought about swarming is put off for a while. They invariably get another super too.
What to do with the frames of sealed brood? My options are: make up a nucleus colony and give them a queen (purchased or over-wintered), use them to boost a smaller colony, or add them to a cell builder if it’s approaching the time for grafting. Making nucs is great if you have queens and want more hives, but not everybody falls into that category. You can, of course, sell nucs to other beekeepers.
Swarm Control
Assuming that I have been doing weekly inspections, I should be able to find that the queen has not yet left for pastures new, even if there are queen cells. It’s not always so, but nothing much is ever certain. The simple and preferred thing to do, for me at least, is to take away the queen in a nuc to a new apiary, leaving a single cell in the parent hive.
Sometimes, if I haven’t got a nuc ready, or I can’t find the queen, but I think she might be there, I do a vertical artificial swarm. At least, I think that’s what it’s called. I put a brood box of mostly empty drawn comb on the floor, with some stores and maybe one frame of brood. Then I shake all the bees into this bottom box so that the queen must be down there (assuming she is still in the hive). Then they get a queen excluder, followed by supers, then another excluder, with a brood box on top containing all the brood. I like to make some kind of upper entrance, using an eke or just a gap between boxes.
The next time I visit, the nurse bees have moved up to the top box, where the brood is. If the queen is in the bottom box, she will have laid plenty, and I can take the top box away or put in a split board rather than the upper excluder. If the queen has gone, I can add one (if available) or add a frame from another hive with eggs on it, plus a frame of sealed brood. This isn’t the ideal place for a fantastic queen to be made (the bottom box) so she’ll almost certainly be replaced later on.
In summary
I think that to prevent early swarming you need to make sure that the stronger colonies get space early, in the form of drawn comb, and some of their brood should be taken away. Regular weekly inspections are needed from late April into June; if you don’t do this, and you miss queen cells, they will swarm. Queen cups are not a problem, and even cups with an egg in can usually be removed and more space provided. Proper queen cells, the ones being drawn out with larvae in, require some kind of intervention. Either take the queen away and leave one cell, or do some kind of artificial swarm.
It all sounds pretty simple. It doesn’t always feel that way, when every hive seems determined to swarm and equipment is running low…