Wednesday, August 5, 2015

Thinking Through Swarms, Splits, and Feeding

Warning: This is one of those rambling posts in which I sort of "talk through" something I've been thinking about, so you may want to bail out now.

Every year, it seems like there is at least one big question that I keep turning over and over in my mind. This year, the big question for me has been about timing splits. More specifically, what is the ideal time to split in order to prevent a swarm but still make honey? 

Austeja, my colony that came through the winter, made a load of honey in the spring, but then most of it got eaten up by the splits I made when she began to swarm. Bummer.  Although I didn't take up beekeeping for just the honey, it would be dishonest to say that I don't want any honey because I do, I do, I do. Even worse, I've had to feed all these splits, and 1) sugar syrup has been shown to be a poor substitute for nectar 2) it's a PITA for me.

Actually, over the summer, this is a complaint that I've heard from other new-ish beeks like myself. They split up queen cells & brood to halt the swarms, divvy up the honey bars between splits, and they still have to feed, feed, feed the splits to ensure they build up before the fall.

When Peter Borst lectured at my local beekeepers' meeting in June, I asked him about this, and he said the best time to split is when you see cues that the colony is preparing to swarm but before the bees start making swarm cells. Cues to look for would include making drones & building queen cups, etc. Although he advised against splitting too early (because a sudden drop in temps could chill brood), he said one could even get a jump on splits 1-2 weeks before the natural swarming period occurs. (In CT, this might be early May, but every location and every year is different.) The bees will quickly replace all the brood they lost at this time, so splitting won't have a huge effect on honey storage.

I thought this was helpful info because it coincided with one of the first pieces of advice I received as a new beek:

Maybe if you live some place really cold or really hot, this rhyme wouldn't hold true since your flows would occur during different months. In my area, though, the main flow occurs between May and June, so that seems right for me.

So I could see how splitting in May, like Peter suggested, would work. However, in observing my own bees and in talking to other TBH beeks in my area, it seems some people started seeing swarm prep around mid-May, but most people's bees didn't begin making queen cells until June or July, which was puzzling to me. If it was more advantageous for the bees to swarm earlier when the main flow was on, why were the bees waiting? Our dearth usually begins around the middle of July. Why swarm right before or during a dearth? (Ok, I concede the bees don't know when the flow will end, but still. They're so in tune with natural rhythms, why not time swarms with the main flow?)

Fast forward...

I finally finished reading Tom Seeley's Honeybee Democracy, a description of his research on swarm behavior. To say the least, it was fascinating and informative, and I can't believe I waited this long to crack it.

Available on

Anyway, he mentioned a couple of things in his book that I already knew, but they took on new meaning for me in light of Peter's comment and the experience that I and others have had with our own near-swarms.

The main piece of info that finally connected all the dots for me has to do with cavity size. Seeley's research says that bees prefer cavities that are approximately 40 liters. We all know bees will build in spaces larger and spaces smaller than 40L, but given a choice, they will pick a cavity approximately 40L.

For those of us stubbornly clinging to English measurements, 40L is approximately 10 gallons. If you've ever had fish or a hamster, you know how small a 10-gallon container is. The thing is, though, that most bee hives are much, much larger than this. For instance, my hive holds about 88 liters.

It's finally dawned on me that perhaps this larger size maybe why my bees, and bees belonging to other beeks I know, don't swarm until June or July. The constant addition of space suppressed the swarming instinct as they are manipulated into filling a larger cavity. However, with a TBH, eventually one runs out of space, and they begin to swarm. Given a 40L cavity, perhaps the bees would fill it faster and swarm earlier. Maybe they'd swarm in May. (Yes, I'm slow. It's only taken me 3 years to figure this out.)

Another interesting tidbit from Seeley's book is that 75% of swarms don't survive the winter, and a majority of those deaths result from starvation due to insufficient stores. He didn't really go into this detail in depth, and I'm curious about it. Does this 75% come from kept or feral bees? Were the surviving swarms from feral or kept bees? What months did the dead/surviving swarms leave their original hive? What types of cavities did they occupy? When was this research conducted? Have changing weather patterns affected counts? Etc. The list of questions goes on. However, if these swarms are leaving their hives just prior to or during a dearth, like the ones I'm hearing about, then it would make sense that they don't have time to build up. Therefore, without constant feeding, they would die out -- just like these late June/July splits we've all been making.

Of course, I've also considered another reason that I have to feed all these splits. According to beeks who've been at this for decades, the flows have changed. In particular, the fall flow is lighter, and the dearth is "dearthier." This year, the spring flow came much later than usual, too. The weather is beyond my control, though, so I'm going to focus on factors that I can manipulate.

Next year, I'm going to try splitting much earlier, before they're well into swarm mode and see what happens. For example, instead of waiting until they've filled out 30 bars, maybe I'll split at 12 or 15, since if they were wild with a 40L hive, that's when they would naturally take off.

Has anyone gone through a similar experience? What do you think?


  1. One of the prominent beekeepers in our area starts his splits in early April. I always thought that was too early, but he seems to have success at that. He doesn't wait for queen cells, but waits for drone combs/drones to appear as his sign it's time to split. He's been bitten by cold snaps, but when he's successful, he has a jump on the rest of us. I waited too long to split my hive this year - I was hoping for some queen cells but all they really need are some eggs and drones and (hopefully) a good flow to come.

    I think the key in TBHs is to constantly provide them with space - either make a split or harvest honey so they won't swarm. If the hive is not full, you can add bars to the brood area to give them some space. Too small a hive is a recipe for swarming. We recently had a discussion about the Golden Mean hives on one of our lists as being too small and prone to swarming. The proposed solution was to build bigger hives.

    I'll have to check out Tom Seeley's book - thanks for the tip. I really need to read more about swarms and splits.

    But, if a hive wants to swarm, it's going to swarm no matter what you do. ;-)

  2. I totally agree, if they want to swarm, they're going to do it. My frustration, though, this year has been having loads of honey, but none of it capped and ready for harvest, and running out of room which led to swarming. :-(

    I've heard the Golden Mean Hive called the Golden Swarm Thrower many times. LOL!

    For TBHs, mine are on the larger side. Interior measurements are 18" across the top, 9" depth, and 8" (or so) across the bottom, 44-46" long. But they still ran out of room, and as you know, it's hard to add more space with a TBH.

    So I'm thinking that next year, rather than let them start swarming at a point in the year when the flow is nearly over, I'd rather force them to "swarm" by splitting earlier while they're still in the mood to build comb (I've noticed that this desire seems to taper off with in my bees after the summer solstice) and everyone has the best chance of success. We'll see. A friend of mine and I were discussing the adage "Anything worth doing is worth doing wrong." So here's to the next season and another year of doing it all wrong. :-)


Thank you for your comment! I can't wait to hear what you think!