A scary, wonderful and frustrating thing, swarming fulfills that spring urge to procreate! Swarming is the term used when approximately half of the colony abandons the hive in search of new premises, taking the mated queen with them.
This typically happens in the spring when the colony expands rapidly on a strong nectar flow and pollen is available in abundance. As the colony grows the hive can become congested. Nectar and pollen stores compound this problem, reducing the laying area available to the queen.
The first phase of the swarming process occurs when the worker bees recognise the lack of available brood space or favourable climatic conditions and reduce the quantity of food given to the queen bee. This in turn causes the queen to lay fewer eggs and lose weight (at full tilt the queen can lay her body weight in eggs every day). This enforced weight loss will enable the queen to take flight when the swarm is ready to leave.
The workers by contrast will fill their honey stomachs with a week’s worth of food to sustain them after they leave the hive. A sunny day in a spell of settled weather is the perfect time for the swarm to take flight, a mix of workers and drones piling out of the hive and circling in the air waiting for the queen to join them. When she leaves the hive, she takes a short flight and will often settle near the hive, where the bees will cluster around her.
In flight the swarm is noisy and can be frightening, but without a territory to defend and their honey stomachs full, they are largely harmless. Once clustered they can be gathered up (if reachable!) and re-homed.
While preparing to swarm, the hive must produce a replacement queen. They will often make between five and twenty-five replacement queens. Starting with queen cups hanging from the frame, an egg or small larvae is laid or placed in the cup. The developing larvae is fed royal jelly as it develops into a queen bee. The first queen bee to hatch then dashes around the hive stinging and killing any competitors, and tearing down residual developing queen cells. This is the reason that the queen’s sting has no barb, allowing her to repeatedly sting without dying.
The single virgin queen will then spend five to seven days maturing in the hive before venturing out, first on an orientation flight and then a mating flight a day or two later. Good weather is required for this to ensure a plentiful supply of drones are available. The virgin queen will mate in flight with up to eighteen drones before returning to the hive. Over the next week the freshly mated queen swells and begins to lay eggs. The colony is then fully functional again.
There are many things that can go wrong during the swarming process – poor weather, aborted swarms, a lost virgin or failure of the queen to mate - so many variables to consider that we could write a book! But this is a rough guide so we’ll leave it there for now.
So, if you have a swarm or if your hive has swarmed – DON’T PANIC!!! – it’s all perfectly natural!