Beekeepers are continually dealing with an array of issues. From parasites and the diseases that they bring, to timing when to add honey boxes and when to take them away... but no issue is more pressing than that of brood management. Luckily, we love a challenge!
Honey bees are instinctually driven, and no instinct is stronger than their drive to reproduce their genetics. They believe that this is accomplished via swarming. When the colony reaches the optimal population and resource capacity, the queen will lay eggs in special cups that the bees prepare that we call queen cups. These eggs will then hatch and the bees will tend to them in order to make new queens. We call these swarm cells. Once the larvae in these cells reaches its maturity, the bees will cap them off so that they may pupate and turn into new queens. About the time that these cells are being capped (sometimes before and sometimes after), the original queen will leave the hive and take about half of the worker population with her. This is a swarm. They will usually land in a tree or any sort of structure for up to a few days while scouts are sent out to locate a suitable new home for them.
Meanwhile, back in the original hive, the new virgin queens are starting to emerge from their cells. While there are many cells, only one queen will survive the next few days. The one that emerges earliest and has had the best nutrition while developing, usually has the best chances at ascending to the throne. She will quickly locate all other swarm cells that had not emerged yet, and chew through the side and kill the queen within. While doing so, they usually cross paths with other virgin queens that have emerged and are doing the same thing, and they fight to the death when they do.
Once her dominance is won, she will be groomed and fed by the workers and then she will begin her mating flights. During these flights she will mate with up to 20 drones in the air in areas a bit farther from her hive than the drones that were created within that hive will travel. This is nature's way of benefiting genetic diversity.
This instinctual need to reproduce their genetics is the basis of all of the wonderful things that honey bees do for us.
In what we humans consider late winter, the bees are already sensing that spring is coming. The queen begins to lay more eggs expanding the size of the brood nest. This calls upon the winter bees, that live far longer than summer bees, to mine the resources from within their bodies and create enough heat to sustain that larger brood nest for as long as it takes until the hives population can successfully switch from winter bees to summer bees.
During this time, the population grows incredibly rapidly. Consider this, with every solid frame of brood that emerges, the new bees will cover as many as 3 frames. So a colony with 20 frames total that has 7 frames of brood to emerge will need 21 frames just to give space for that one brood cycle. If this congestion is coupled with an inflow of resources (pollen and nectar) then this hive is primed to swarm. If the hive swarms, the swarm has little chance of surviving parasitic infections and predation, and the hive will have lost the population that gives us the massive honey crop that we want. And even worse, the new virgin queens are very likely to not find enough drones to mate properly (meaning she will be superseded later on causing yet another month of setback), or she may be eaten by a bird while trying to mate and now the hive is hopelessly queenless with no way of creating a new queen on their own.
As beekeeper's, we welcome this spring build up. Even though it can be a trying time indeed. We have our work cut out for us. Over the winter, we spent numerous hours working hard on preparing new boxes, frames, bottom boards, and tops, to be able to keep up with these instincts and stay just ahead of them.
Swarm control means taking away to keep them with space to expand while still allowing the population to increase as the honey supers begin to go on during the flow.
It's a very thin line that we walk and this is the very aspect that differentiates one beekeeper from another. It's simply not something that can be taught, each beekeeper has to figure out their own ideal balance from all of the variables in play within his/her apiary.
In our area, we generally use Valentine's day as a marker. Watching the weather religiously, we time the first inspection right around that date. With pollen patties and syrup at the ready, we tip our colonies back to peak at the bottom of the frames instead of looking down from the top. This allows us to count the number of frames of bees that each colony has and we can mark each one with a general size identification mark.
Due to the weather being less than hospitable that time of year, we immediately feed every hive with a pollen supplement (to help feed larva) and the very large hives or very light weighted hives will get a 1:1 sugar syrup feed (to help feed the bees). This rapid growth can not only mean swarms, but also starvation. If the hive outgrows it's available resources and the weather turns bad so they can't get out to gather it themselves, then the colony can quickly starve to death, and at minimum can fall susceptible to brood diseases.
At this point the clock is ticking.. after 1 to 2 weeks, we check again to see if the bees have taken down the syrup, eaten the patty, and most importantly, if the number of frames of bees has increased, decreased, or remained the same. If they have increased, then a second brood box is placed above them.... but wait, it's not that simple.... there is a weather and temperature factor that needs to be taken into account here. If it's going to be too cold and over the flowing 12 days and the colony is 6 frames or less of bees in a 10 frame hive, then we will need to try to either hold off on adding the second box on top, or consider adding that second box below the original instead. This keeps the ceiling dynamics in place within the hive.. they have organized the brood, food, and bees in such a way that they can produce enough heat below the hive top to keep that space warm. Adding a box below will allow them to maintain that dynamic, however, you will have to return to reverse this box once the weather gets better, so it's hard for any of us to pull the trigger on some plan of action that will cause us to have to double our work load.
The second brood chamber that we add is specifically organized. In the center we place 4 open brood combs, then honey frames on each side of those and finally foundations on the outsides of those. This encourages the queen to move up (as she naturally will want to do) and lay brood in the center 4 frames. We will wait 3 to 4 weeks and then we will go back in and put that queen back in the bottom box and then take that whole second brood chamber away as a full split to start a new hive with. While doing this, we place a fresh second brood chamber right back in its place.
The split will get either a mated queen or a ripe queen cell and be placed in a new bee yard. The original hive now has had its first artificial swarm and no bees were lost in the process. Even better, the colony population is still increasing more so than it ever would had it swarmed. In 3 - 4 more weeks, we will be placing our first honey super on the hives. Before we place it, we first move that queen back down to the bottom yet again and this time we place queen excluders on the top of the bottom brood box. This keeps her below and allows the brood that she laid above it to emerge and the bees will backfill that box with honey as well.. again, increasing the population dramatically, yet giving them the honey super to immediately have a place to move up into. If the weather has worked with us, this timing is right around mid April giving us the best honey flows (April, May, June, and early July) to capture in our supers.
That isn't where swarm prevention ends though. It is a continual guessing game all the way through the end of June. Stacking on more and more honey supers to keep the bees busy and moving upward is a huge benefit. But from time to time, we may still need to pull them down a bit by pulling 1-3 frames of brood from them.
By early July, we are in full swing pulling honey for extracting. This is also the time when we begin our summer split. This is when we simply pull nucs from every hive and start them with new mated queens in separate yards. Some of these will be placed into two story 5 frame hives to allow them to draw comb and store honey for us in the top box, which we will use in spring while creating our second brood chambers for that early full split. Others will be placed into new 10 frame singles and encouraged to draw foundation out and be prepped for winter to be honey producers in the following spring. The five frame nucs that we over winter will be instant replacements for any hives that do not make it through winter for whatever reason.
I hope this blog helps to explain the timing, the necessity, and the usefulness of proper swarm control.