Swarming is the reproductive mechanism of honeybees. In early spring when pollen and nectar are available, bees will raise many more bees. After they have raised enough bees, and replaced the food that the hive used over winter, they will issue a swarm.

Before the hive issues a swarm, they will start raising new queens, and reduce the amount of larva that the hive nust feed. While the new queens are still developing, the old queen, and approximately half of the worker bees, and some drones will leave the hive to find a new home. When the swarm leaves, they will take approximately half the honey that is stored in the hive.

Honeybees will not endanger the parent hive in order to issue a swarm. If the hive does not have enough resources gathered to ensure the survival of the parent hive, and give the swarm a good chance of survival, they will not swarm.

When a swarm leaves the parent hive, they will usually cluster together on a tree branch while scout bees look for a new home. When the scouts find a suitable location, they return to the swarm and communicate the quality and location of the new home to the rest of the swarm. The swarm then chooses which new home to take up residence in.

If a beekeeper can catch a swarm before they find a new home, the beekeeper can make a new hive from them by placing them in a hive box and moving them. This helps ensure that the swarm does not take up residence in the wall of someone's house, or in a location where they will come into close contact with humans.

Honeybees that are part of a swarm are usually calm, and gentle. Because they are not protecting a hive, they are very unlikely to sting. It is not uncommon for beekeepers to walk up to a swarm and examine them closely without protective gear on. That does not mean that a swarm can not be provoked into stinging.

However not all swarms are calm. Africanized swarms can still be a danger to humans or pets. If you live in an area with Africanized Honeybees, do not approach any swarm unless you're a beekeeper who knows how to handle honeybees. Even if you do not live in an area with Africanized bees, it would be wise to stay away from the swarm, and call a beekeeper to remove them. Do not attempt to spray a swarm with a water hose or pesticides. Spraying a swarm is like poking a bear with a stick, and can be hazardous to your health.