Bait hive, swarm trap, and swarm lure
These terms overlap. A bait hive or swarm trap is a box set out to look like a good nesting cavity so that a swarm looking for a home will move in. A lure is the scent you add to make the box more noticeable. Many beekeepers use simple, cheap boxes, and some use a spare hive body.
Setting traps is a way to catch swarms that came from other colonies, or from your own. It is also one of the more practical ways to add colonies without buying bees. If your goal is to stop your own colonies swarming in the first place, see swarm cells and splitting a bee hive.
When to set out a bait hive
Swarming happens mainly in spring and early summer in many temperate regions (see when to start a bee hive for timing a new colony), though the exact timing depends on weather and forage. Bees respond to conditions such as warm weather combined with a nectar flow rather than the calendar. Put your trap out a few weeks before swarm season where you live, so scouts have time to find it. Seeing swarm cups or cells in your own hives is another cue that local swarm season is beginning.
What makes a cavity attractive
Researchers who study how swarms choose a nest, notably Thomas Seeley, found that bees favor cavities of about 40 liters with a small entrance. A standard ten-frame Langstroth deep body (see the bee hive size guide) is in roughly that range, though sizes vary by manufacturer. Other features that scouts seem to like:
- A dry, sheltered interior with no draughts
- A small entrance (see bee hive entrance size), often described as about the size of a few square inches, which a colony can defend
- An entrance near the bottom
- Some scent of previous bees
Swarms do move into all kinds of cavities, so a trap does not need to be perfect. A box that is far too small is more likely to be ignored.
What to put in the trap
- Old comb. One or two frames of old, dark brood comb are often recommended because the smell signals a previous colony. Fill the rest with empty frames or frames with starter strips.
- Lemongrass oil. Many beekeepers add a very small amount, often one or two drops on a cotton ball or at the entrance. The scent is thought to resemble a pheromone scout bees use. Too much can repel bees, so go light. Commercial lures are available too.
- Beeswax or propolis. A little rubbed on inside surfaces adds scent.
Avoid strong smells such as cleaning products or paint inside the box. Let new wood air out first.
Where to place it
Placement advice varies between sources. Commonly suggested are heights from a few feet to roughly ten or fifteen feet off the ground, with the entrance facing south or southeast in cooler climates, some afternoon shade in hot ones, and protection from wind and rain. Place the trap near known swarm landing spots, near your own apiary, or along the edge of trees. Secure it so it cannot fall, and make sure you can reach it safely. Do not hang a trap from a ladder you cannot manage alone.
Check local rules and get permission from the property owner before placing traps on land that is not yours.
How scouts behave before a swarm moves in
Scout bees investigate possible sites over hours or days, hovering around the entrance and inspecting the inside. A trap that is being considered may have a handful of bees visiting, and sometimes many more the day before a swarm arrives. If you see this, try not to disturb the box or move it, since that can put scouts off. For general entrance activity that you may mistake for scouting, see reading bee behavior at the hive entrance.
What to do when a swarm moves in
Once bees occupy the trap, leave them alone for a while, often at least a week, so they settle and start building. Then, if the box is a standard hive body, you can move it to your apiary (see where to place a bee hive) at night after the bees have all gone in, closing the entrance carefully and handling it safely. Moving a box that is high up requires care. After relocating, check the colony for queen, brood, and health, and monitor for varroa as you would for any colony.
A swarm that moves into a trap has no stores, so you may want to feed it until it builds comb and finds forage.
How long will a swarm stay in one spot?
A swarm that has just left a hive typically clusters nearby while scouts search for a home. This can last from minutes to a few days, depending on how quickly the scouts reach agreement. After that the swarm lifts and flies to the new site. If you see a swarm cluster, try to collect it promptly.
Swarm seducers and catching visible swarms
Writers at Honey Bee Suite have described a “swarm seducer”, which is a piece of old brood comb melted onto rags and hung in a tree near the apiary so that a swarm leaving your hive lands there. It provides a temporary stop, not a permanent home, and is meant to make collection easier. It is an anecdotal technique rather than one with strong evidence.
If nobody moves in
- Check that the box is dry, clean, and not too small.
- Add or refresh comb.
- Move traps to more promising places, such as where swarms have landed before.
- Use more than one trap.
- Be patient. In some areas few swarms are available, because wild colonies are scarce.
FAQ
What is the 3-3-3 rule for bees? The phrase is used in different ways. One common version, about relocating hives, says to move a hive either less than about three feet or more than about three miles so that foragers do not get lost (the figures are approximate). Because meaning varies, check the context where you read it.
What can I put out to attract honey bees? A suitable box with old comb, a tiny amount of lemongrass oil, and sheltered placement is the usual combination. For helping bees in general, see increasing the bee population.