Swarming is the natural means of reproduction of honey bee colonies. A new honey bee colony is formed when the queen bee leaves the colony with a large group of worker bees, a process called swarming. In the prime swarm, about 60% of the worker bees leave the original hive location with the old queen. Secondary afterswarms may happen but are rare. Afterswarms are usually smaller and are accompanied by one or more virgin queens. Sometimes a beehive will swarm in succession until it is almost totally depleted of workers. Entomologists consider the colony as a superorganism.
An individual bee without a colony cannot survive for long. It also
needs a certain colony size to reproduce. In the process of swarming
the original single colony reproduces to two and sometimes more
colonies.
Swarming is mainly a spring phenomenon, usually within a two- or
three-week period depending on the locale. But occasional swarms can
happen throughout the producing season.