The 3 Stages of Swarming
Sophia Grant recently proposed that swarming can be divided into three main stages defined by the behaviour of a swarm. More information about why bees swarm can be found here
Stage 1 - Flight
Stage 1 involves the bees leaving the hive with the queen. At this stage the bees appear to be flying in a chaotic fashion, however they are picking up the scent of the queen in flight and are looking to follow the queen.
This is a video of a swarm in flight looking to settle in a tree
Stage 2 - Settling on an Object.
In this stage the queen rests and settles on a branch or a wall (or sometimes even a car). The swarm then sends out scout bees to look for a suitable location for the hive to move in to. Once they have found a location, they report back to the swarm and the swarm can, once again, take flight and find the new location.
This stage is typically what people recognise as a swarm.
This is the state in which we can catch the swarm.
Stage 3 - We’ve moved in !!
Once a swarm has found a home and moves in it has achieved its primary goal of splitting from its original hive has established another hive.
The queen and bees move into the cavity and begin to make wax and establish a hive. Once they are at this stage it is virtually impossible to get the hive out without disassembling the wall or structure and removing them by hand.
Typically all that can be seen are some bees entering and exiting a small hole in a wall or roof cavity.
More information is available here.