The onset of the swarming season occurs from mid-May to late June, coinciding with a plentiful supply of food. From March, honeybee colonies will have been expanding, despite the cold and wet, filling the beehives to capacity with their numbers.
This scenario leads to bee colonies propagating. A series of events take place which eventually leads to the colony splitting, by issuing a swarm or perhaps a series of swarms.
During the preceding months honeybee colonies have been stealthily increasing in size. The queen has been laying large numbers of eggs daily. As the eggs hatch into larvae, the demand for food to maintain them increases. So too does the food requirements increase for the adult bees.
Honeybee colonies are fully in tune with the cycle of nectar flows from flowering plants and will use this opportunity to propagate by swarming. Any swarm issuing from a hive will therefore have a reasonable chance to become established and survive.
Prime swarm
The mechanisms which lead to swarming are set in motion as soon as the colony numbers increase to the point where the hive becomes crowded. This crowding leads to difficulties in the transfer of queen pheromone (queen substance) amongst the bees.
This pheromone, which is passed amongst the bees, assures them that their queen is still present. Once the distribution of queen substance breaks down, a sequence of events is triggered within the hive.
Queen cells are prepared in which the queen will lay an egg and eventually these cells produce new queens. When the first queen cell is sealed, the reigning queen takes off in a swarm with a large number of bees.
These are the bees needed to produce the honey crop. Some days later, that first sealed queen cell will hatch and a new queen will take over in the hive. However, should several queen cells have been produced, the sequence will repeat with each queen taking off with a swarm. The first swarm is termed a “prime swarm” and subsequent issues “castes”.
At some point, this throwing of castes will cease as the number of worker bees decline. It may happen that bees will tear down unwanted queen cells, putting an end to swarming. In some cases, where several queen cells hatch in unison, the resultant queens will seek each other out and a fight to death by lethal sting will see the survival of the fittest queen.
Beekeepers will, at this time of year, carry out weekly checks to prevent the loss of bees through swarming. They add extra space to relieve the congestion thereby alleviating the problem of queen substance distribution.
However, despite this manoeuvre, swarming preparations may still proceed. Should the beekeeper not intervene, a swarm may issue. Beekeepers, carrying out regular swarm control checks, can, on finding queen cells, prevent the loss of their bees.
There are multiple variables and an array of techniques associated with swarm control. Beekeepers use the production of queen cells in making up nuclei, queen replacement or queens for sale.