Asian hornet trap: how to make it - illustrated tutorial

Where and when should you install an Asian hornet trap?

When to install the trap?

As soon as they emerge from hibernation, founding females will seek to build their nests. Traps must therefore be set at the start of the nesting period, when daytime temperatures exceed 13°C, that is from mid‑February in the mildest regions and up to mid‑April. Beyond that, the trap becomes useless because queens will have built their nests and will not leave them.

Note: Outside these periods, remove the trap to avoid accidentally catching European hornets. Also check that any hornet caught is Asian and not European; if not, release the insect to preserve biodiversity.

Where to install the trap?

Place your trap near a pile of wood, close to a body of water sheltered from prevailing winds, in a flowery area and, of course, near hives.

Materials needed to make the trap

To make your trap, you will need:

• 2 plastic bottles of water
• 1 tongue depressor (available from chemists) or, failing that, 1 ice lolly stick cut in half
• 1 craft knife
• 1 pair of scissors
• 1 foam disc
• 1 ruler
• 1 felt-tip pen

For the bait, you will need:

• beer, preferably alcohol-free,
• some honey or cider,
• some syrup or apple juice.

Making the trap

To make your Asian hornet trap, you must :

• cut the first bottle in two, roughly at the halfway point, using a craft knife or a pair of scissors.

Cutting first bottle

• cut a foam disc (or if unavailable a wood disc) the size of the bottle’s inner base and place it in the bottom. This foam will be soaked with bait and insects will not be able to drown in it.

Placing foam / making exit opening

• draw then cut a rectangle no taller than 5.5 mm, just above the surface of this foam. This will be the lower exit. Make a notch to insert a half-stick. Ensure the notch width matches the stick width. Finally, refer to the diagram below.

Diagram of lower exit opening

Size of the lower exit allows small insects to exit unharmed while Asian hornet remains trapped.

• take the other part (with the neck) of the same bottle, remove the cap and turn it over to fit it into the first part.

• make the second opening according to the diagram below. To do this, draw then incise a rectangle no taller than 9 mm. This will be the upper entrance opening. Similarly, make a notch to insert the other half-stick.

Diagram of upper entrance opening

This opening is large enough to allow Asian hornets to enter. Larger European hornets cannot pass.

• cut the second bottle and keep only the part with the neck. Fit it onto the top of the trap. It must not block the entrance (if it does, make a notch; a simple rotation of this part will close the entrance to prevent escape). Put the cap back on and insert the sticks into the slots provided. These serve as landing and take-off perches.

Fit top part / finished trap

As all parts are removable, you can disassemble and reassemble the trap to add bait or free insects that did not find the exit or are too large to pass through the lower opening.

Parts may become stuck together. In that case, simply clean the trap with hot water, replace bait and reassemble the trap.

How to eliminate Asian hornets :

The trap will probably not contain only Asian hornets. To release other insects unharmed, place your trap in the fridge for 1 hour to numb them. Then simply crush the Asian hornets and release all others.

To find out more...

• Note that a 100% selective trap does not yet exist and you may accidentally capture other insects, including the European hornet, which is far less aggressive. We recommend releasing any insects accidentally captured in this trap to protect biodiversity.
• Discover Olivier’s advice sheet to learn all about the Asian hornet, its behaviour, control and prevention : “Asian hornet: how to recognise and combat it“.