Bee Swarms are the natural way that bee colonies multiply to increase their numbers. In the world of bees, an individual is not the important entity, as most bees cannot reproduce. The important unit is the colony, which contains a queen (or occasionally multiple queens) responsible for laying eggs which the colony as a whole hatches and raises. It is therefore important for the survival of bees, that colonies "reproduce", which is done by the bees splitting into two groups, one of which stay in the hive, and the other departs to find a new hive. The departing group is known as a swarm.
The queen usually leaves with the swarm, so the group remaining behind has to raise a new queen to remain viable. The colony will have started the process by having a number of larvae nurtured to become queens, and left to complete their pupation. However, this process is risky and the remaining colony may end up without a queen, which means that it will collapse and die out as the existing bees individually die, or abscond to join another thriving hive.
The swarm will normally settle temporarily near to the original hive while scout bees search for suitable places in which the swarm can establish a new hive. There will eventually be "agreement" among the scout bees and over the most suitable location, and the swarm will then depart to take up residence in their chosen location.
Beekeepers always try to capture a swarm while they are in the temporary settled mode prior to relocating to their new home, as they are easy to place in a hive prepared by the beekeeper. There are various methods of getting them into a box or other container depending on where they have settled. A favourite spot for bees is up in a tree, which is relatively sheltered. This means that reporting a swarm as soon as possible after it has settled makes it easier to capture.
Dealing with Unwanted Swarms
If you have a swarm and are unable to call a beekeeper or other person to collect it, or want it removed promptly, then you may need to destroy it. Do not try to hit the swam or throw things at it as this will be quite ineffective. Flying bees can be calmed with water - fine spray from a hose to simulate rain will cause them to settle quite quickly.
If you do need to destroy a bee swarm, then the quickest and easiest way is to mix up a solution of detergent and water in a spray bottle and thoroughly soak the bees. While plain water will not harm them, water with detergent or soap will cause their bodes to get wet and will block their small breathing holes, so they drown quite quickly.
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