A difficult occurrence for beekeepers is swarming.
Beekeepers will try to prepare their hives to prevent swarming but it can be difficult to do if they have already created swarm cells. Swarm cells are multiple queen cups clustered together at the bottom of a frame (at this point it may be too late to prevent swarming).
Beekeepers want to be proactive and prevent swarming before it even begins.
Swarming is a natural means for a colony to reproduce.
Bee colonies are considered superorganisms
and may swarm/reproduce several times throughout the season. Swarming season will typically happen after the queen has made it through winter, leading into the spring or early summer months. A newly established colony does not have the tendency to swarm but may, if they become overcrowded.
There are three conditions which can induce swarming preparations:
Congestion. Bees love to be crowded but not overcrowded. Having your brood chambers well populated allows the bees to maintain a constant hive temperature, prevent robbing and manage pests. A well-populated hive will be a healthier hive. Once a hive becomes congested and the colony can reproduce (without compromising the survivorship of the parent or the offspring) they will swarm to a new location to better satisfy their needs. In order to prevent congestion, continue adding supers to accommodate your colonies expansion. Remember that once the two outside frames are beginning to be worked, it is time to add the next super.
Abundance of Resources. During a heavy nectar flow, bees are gathering the resources they think they will need to survive during the winter months. This is what beekeepers hope for so that honey may be extracted. Beekeepers do not want the abundant resources to overrun the brood chamber creating a honey bound hive. Once bees are hatched and the cell is filled with pollen and nectar, the queen will not have room to lay. Replace some of the honey filled frames with empty frames, allowing the queen to build up the brood nest.
Old Queen. As a queen ages, her pheromone levels will decrease. If a colony notices a drop in her pheromones, they may begin developing swarm cells for her to lay eggs into. Workers will then slow the queens laying by reducing the amount she is fed, slimming her down for flight. Queens going into their second laying season are more apt to swarm. To help prevent swarming, beekeepers will replace them. A two year old queen is 3X more likely to swarm.
Colonies coming out of winter will continue to increase in population and the hive will continue to grow. Beekeepers have the option of creating a controled swarm by splitting their hives. This would include removing frames of brood (in all stages) and honey from your mother hive, transitioning them into a new hive or NUC, and introducing a new queen to the split. The split hive will grow in population as the brood emerges and the new queen begins to lay eggs. For more information on createing splits, read this blog!
These are proactive steps to help prevent swarming. They may or may not work. If swarming does occur, have your Cardboard NUC handy and go out and retrieve them (read more in Swarm Retrieval).