Collecting Swarms

Catching a swarm means taking a honey bee swarm that has left its hive and clustered on a branch, fence or wall, collecting it in a box and settling it in a hive. A freshly settled swarm is usually calm; with the right equipment, the right timing and a few simple steps you can both recover your own escaped colony and gain a new one.

What is a swarm, and why is it calm?

A swarm is the honey bee colony's natural way of reproducing: the old queen and part of the workers leave the hive to found a new nest, while queen cells and young bees stay behind in the old hive. The first large swarm to leave is called the prime swarm, and later ones are called secondary swarms or casts; these are smaller and usually carry an unmated (virgin) queen.

Before leaving, swarming bees fill their honey stomachs. They also have no brood or combs to defend. That is why a freshly settled swarm is often the gentlest mass of bees in beekeeping. However, if the swarm has gone hungry for days or been rained on, it is less calm.

Where does a swarm settle, and how long does it stay?

After leaving the hive, a swarm usually settles on a nearby tree branch, bush, fence or wall. From there, scout bees search for a suitable nest site and report the site they find to the others by dancing. This wait can last from a few hours to a few days; most swarms move on the same day or the next.

That is why you need to act quickly when you see a swarm. The swarming season varies by region but is usually late spring and early summer; most swarms emerge around midday on warm, sunny days.

Equipment needed to catch a swarm

• Swarm box or nucleus hive: A ventilated box with a tight-fitting lid, or a small hive with frames inside.
• Protective clothing: A beekeeper's veil and gloves should always be with you, even if the swarm looks calm.
• Bee brush or feather: For gently sweeping bees that cannot be shaken into the box.
• White sheet or cloth: For putting the box on the ground and letting the bees walk up to the entrance.
• Pruning shears and a ladder: For cutting branches at a manageable height; working at height brings its own risks.
• Water sprayer: A light mist of water can reduce the number of bees taking flight.

How do you catch a swarm? Step by step

1. Assess the situation: Check how high the swarm is, how safe the ground is, and the people and traffic around. Don't attempt a swarm in a dangerous position.
2. Hold the box right under the cluster: The closer the box, the more bees fall into it.
3. Shake the branch with one sharp movement: Most of the cluster falls into the box. Don't close the box straight away; cover it loosely.
4. Put the box in the shade, close to where the cluster was: Leave the entrance open and watch for a few minutes.
5. Read the bees' behaviour: If bees at the entrance are fanning (scenting, with their abdomens raised) and walking in, the queen is inside. If the bees are leaving the box and returning to the old branch, the queen is still outside; repeat the process.
6. Wait for evening: Once the foragers and stray bees have gone into the box, close it at dusk and move it.

For a swarm that has settled on the ground or a low bush, putting the box directly above or beside the cluster and laying a sheet up to the entrance like a ramp may be enough; once the queen goes in, the bees march in by themselves.

Hiving the swarm

1. Prepare the hive: The hive should contain frames fitted with foundation or drawn comb. A swarm carries young bees ready to produce wax, so it draws foundation quickly.
2. Tip the bees in: Shake the swarm into the hive, or empty it onto a cloth spread in front of the hive and let it walk into the entrance.
3. Give a frame of open brood: A frame of open brood from another healthy colony markedly reduces the chance of the swarm absconding.
4. Reduce the entrance and protect the hive against robbing.
5. Feed after a few days: The swarm first uses the honey in its stomachs to draw comb. If there is no flow, give thin syrup after a few days.
6. Leave it alone: Don't open the hive in the first week; then check for eggs and regular comb building.

Catching swarms with a bait hive

A bait hive (swarm trap) is an empty hive hung up in a suitable spot during the swarming season for scout bees to choose as a home. The beekeeper doesn't catch the swarm; the swarm comes and moves in by itself.

• Volume: A box of roughly one standard brood box in volume, close to the cavity size bees prefer, is suitable.
• Scent: Putting an old, disease-free comb or frame inside makes it more attractive. The comb must not come from diseased colonies.
• Location: Choose a shady spot a few metres off the ground, with a clearly visible entrance.
• Checking: Check the trap once a week; transfer a swarm that has moved in to a framed hive within a few days.

Health check of a caught swarm

A caught swarm often comes from an unknown source. Before adding it to your apiary:

• Keep it apart: If possible, keep it under observation for a few weeks at a separate site away from the apiary.
• Check the brood: When the first brood is capped, look for signs of foulbrood, chalkbrood and a patchy brood pattern.
• Check the varroa level: Because a swarm arrives without brood, all its mites are on the adult bees. This is the most favourable window for treatment with an authorised varroa product; apply it before the first brood is capped.
• Don't move combs or frames: Don't give frames from this colony to other hives until you are sure it is healthy.

Safety and responsibility

• Get permission before collecting a swarm on someone else's property.
• Keep people nearby at a distance, especially children and anyone allergic to bee stings.
• Don't work alone on a ladder; cutting short branches and lowering them is safer than shaking at height.
• If you want to respond to swarm calls, keep in touch with your local beekeepers' association or the municipality; this gains you colonies and strengthens beekeeping's standing in the community.