Swarming is an essential part of honeybee behaviour.
When a fertilized queen leaves the hive she takes a
swarm of bees with her to start a new colony. Up to
20000 bees might accompany a newly fertilised queen
bee on her quest. These bees usually form a cluster and
cling to each other for several days whilst scouts leave to
search for a new home to relocate to. The bees, exposed
to the outside temperature, are at risk of getting too cold
but in their tightly packed cluster they may also become
too hot.