Ann Chilcott, Scottish Expert Beemaster, offers advice on taking advantage of swarm season.

One way to get free bees is to entice swarms into your garden. I set up a bait hive which has been successful in attracting some of our most illustrious insect pollinators and honey makers into my apiary.

Swarming is one of the main reproductive strategies of honey bees and is what strong healthy colonies want to do in late spring to midsummer, the timing depending on local foraging conditions and your location in the UK. Other factors influence swarming such as: large colony size; brood nest congestion; reduced transmission of queen pheromones; and an abundance of incoming nectar. Swarming is a natural process with advantages and disadvantages for the beekeeper.

What happens when bees swarm?

In a nutshell, the hive gets overcrowded and the old queen leaves with around 10,000 workers bees, a high percentage of which are young wax making bees ready to set up a new home and furnish it with wax comb. Scout bees will have already been out and about looking for the best “des res” in the area.

Smallholder:

Ann with a swarm last May in her Highlands home

The swarm leaves a hive and clusters on a tree whilst the bees decide where to go. The scout bees perform dances on the swarm cluster to advertise the potential new homes. The most vigorous dances gain most attention from the swarm bees till eventually the bees advertising less popular sites stop dancing. A consensus is then reached and off they go to their new home with the scout bees assisting with navigation (1). More on ideal homes later as this is key to setting up bait hives.

Populations in bee colonies naturally increase from around 10,000 at the end of winter to around 40-50, 000 or more at the end of June so that colonies can have a strong workforce to gather the nectar available during periods of plenty. The queen releases chemical signals called pheromones which indicate to the workers that she is laying normally, and that all is well. These pheromones promote colony cohesion. However, when the colony becomes crowded with bees the pheromones don’t circulate efficiently and the bees create several queen cells in which to raise new queens—they may think that their queen is no longer working well. Although research cannot yet tell us exactly what triggers swarm preparation, other factors such as no more room for egg laying in the brood frames and overheating in the hive are thought to influence the swarming urge.

Difficulties of swarms

A beekeeper must learn about bee biology and behaviour if swarming is to be managed and a honey crop obtained. One disadvantage of swarming is that it usually occurs during the height of a honey flow and bees will load up with masses of stored honey to transport to the new home leaving the honey supers (boxes where honey is stored by the bees) markedly depleted. Many new workers leave in the swarm so the foraging force of the colony left at home reduces. There may also be the nuisance factor in swarming if neighbours are not happy about having unwanted bees settling in their gardens.

Once an irate new beekeeper called telling me that he had just come back from holiday (in swarm season?) to find that someone had stolen the honey that he hoped to harvest. I asked him if he had lost equipment, and if had seen the queen at the last inspection— the answer was “no” to both questions. The bees had taken the honey and swarmed but there were still so many bees left behind the beekeeper hadn’t considered that possibility.

One of the advantages of swarming is that levels of parasitic varroa mite reduce within both the swarm, and the colony left at home to raise a new queen, because they have a break in brood rearing. This means that varroa, that only breed in the bee brood cells, have a break too in raising offspring. However, a swarm landing in your bait hive may be carrying many varroa on the bees’ bodies so they should be treated before the queen resumes egg laying.

Get started in beekeeping

To look after bees well they must be regarded as livestock and treated knowledgeably and with respect, but there is nothing to stop you from catching a swarm and getting help from a local beekeeping association during the season as you learn more about bees. Bear in mind that a swarm may carry a heavy parasitic mite load, or another contagious bee disease so it is worth asking an experienced beekeeper to check them over with you.

Setting up a bait hive

Find out when swarming is likely to occur in your area and set up your bait hives a few weeks in advance. The departure of a swarm takes only five to ten minutes but noticeable preparations begin up to ten days in advance. I noticed a few scout bees investigating the entrance of my bait hive before they actually moved in some days later.

Smallholder:

Research carried out in the 1970s (2) yielded recommendations regarding bait hive design based on bee preference:

1. Capacity volume: 1.0 to 1.5 cubic feet.

2. Cavity shape: unimportant.

3. Entrance area: 1.5 to 2.5 square inches.

4. Entrance shape: unimportant.

5. Entrance position: near the floor

6. Entrance direction: facing south of southwest is preferred, but other directions are acceptable.

7. The state of being dry and airtight: dry and cosy.

8. Odour: the odour of beeswax is attractive.

9. Height: about 15 feet off the ground is most attractive but swarms will still be attracted if bait hives are 6-10 feet above ground.

There are commercially available swarm lures that mimic bee pheromones and attract swarms but essential oil of lemongrass works just as well and is much cheaper.

Smallholder:

You might build your own bait box. I used the brood box from an old hive and attached a hinged waterproof lid and positioned the hive on a tree around seven feet off the ground. I have also caught swarms in bait hives placed on the ground and these are a lot easier to move around when full of bees. I place inside the bait hive frames some sheets of comb already drawn out by the bees, and some new wax foundation for the bees to prepare themselves. It is easier to transfer the bees to a new hive if they are on moveable frames and combs that will fit in the new hive.

Siting a bait box

Bait hives need to be visible to bees, and also well shaded otherwise they may abandon hives positioned in direct sun. Bees may prefer to nest away from other colonies so if you already have an apiary it is good to position bait hives at least 300 feet away.

Don’t be tempted to bring down the bait hive too soon after a swarm has arrived. Wait till you see worker bees carrying pollen loads into the entrance on their back legs and you can be sure that the queen is laying again.

To remove the bait hive you will need protective clothing, smoker and equipment as you would to handle any hive that you are moving. Work when darkness, cool temperatures or rain have caused all the bees to move inside. Gently puff smoke at the entrance to coax any lingering bees inside. Use foam and duct tape to close the entrance. Using a hammer to board up the entrance will stir up and stress the bees.

Get some assistance and use a ladder and ropes. You can secure the hive with one end of the rope whilst passing the other end round the tree and tie it to the ladder to secure it whilst you unfasten the bait hive. Then you can slowly lower the hive to the ground, once it is free of the tree and you have untied the attaching rope from the ladder.

If the bees are to be kept in an apiary near where you caught them they must be moved at least three miles away for at least three weeks before being returned to your garden. This is because the swarm bees will have orientated to the hive in the tree, and if moved-- more than three feet away, but less than three miles-- from this site they will return to the tree rather than to the hive you placed in the new site. Alternatively, you can place the hive below the tree and move it about two feet every day till the permanent location is reached.

Good luck!

References:

(1) Seeley, T.D., 2010. Honeybee Democracy. Princeton University Press.

(2) Seeley, T.D., 2012. Using Bait Hives. Bee Culture. April 2012.pp 73-75.

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This article was first published in Smallholder magazine. For regular articles on beekeeping subscribe here, call 01778 392011 or email subscriptions@warnersgroup.co.uk.