Asian Hornets at the Apiary: Watch, Record and Report

The Asian hornet (Vespa velutina) is now established across much of Western Europe, including Belgium, the Netherlands and France. For beekeepers its impact is rarely a single dramatic attack. It is steady pressure: hornets hovering at entrances, foragers staying home, and colonies entering autumn weaker than their stores suggest.

You cannot remove the hornet from the landscape on your own, but you can recognise it early, reduce the stress on your colonies, and make sure sightings reach the people who locate and remove nests.

Recognising the Asian Hornet

The Asian hornet is slightly smaller than the European hornet and much darker. Look for a mostly black body with a single broad orange band near the tip of the abdomen, an orange-yellow face, and distinctly yellow leg tips. The European hornet is larger, with a brown-and-yellow abdomen and brown legs.

Confusion is common, and native insects such as the European hornet deserve protection. If you are unsure, take a clear photograph rather than killing the insect. Local reporting services usually ask for a photo to confirm the identification.

The Behaviour That Gives It Away

Asian hornets "hawk" in front of hives: they hover facing the entrance, a short distance out, and snatch returning foragers in flight. Pressure typically rises from late summer into autumn, when hornet colonies need large amounts of protein for their own brood. Several hornets at one entrance, foragers reluctant to fly, and bees clustering defensively on the landing board are all signs worth recording.

What Hornet Pressure Does to a Colony

The losses from direct predation can be modest. The larger effect is "foraging paralysis": workers stop flying when hornets are present, so pollen and nectar intake drops at a time when colonies are raising winter bees. A colony under sustained pressure can look calm inside yet carry less pollen and a smaller winter population than expected.

Weak colonies and small nuclei are most vulnerable. A strong colony with good stores and a manageable entrance is better placed to defend itself and to keep foraging between attacks.

Protecting Colonies Without Harming Other Insects

Entrance reducers help bees defend a smaller gap. Some beekeepers fit muzzles or wire-mesh entrance guards that give foragers a protected landing area where hornets cannot hover directly at the entrance. These measures are inexpensive and do not affect other wildlife.

Traps need more caution. Unselective bait traps catch many non-target insects, including flies, moths and native wasps. Rules on trapping vary by region, and many advisory bodies recommend only selective traps, used for monitoring or during specific periods, and checked frequently. Follow your local guidance rather than hanging traps by default.

Keep colonies strong going into autumn. Manage varroa on time, ensure adequate stores, and unite small colonies that are unlikely to survive both hornet pressure and winter. The autumn colony preparation guide covers the wider checklist.

Report Sightings and Nests

Nest destruction is the most effective control, and it is a job for trained teams. Do not attempt to remove a nest yourself; Asian hornets defend nests vigorously and nests are often high in trees.

In Belgium, sightings can be reported through the regional reporting platforms (such as vespawatch.be in Flanders or the Walloon reporting service); in other countries, use your national or regional reporting route. Include a photo, the date, the precise location and the direction hornets fly away from the apiary. Several observations of flight direction from different points help teams triangulate a nest.

Keep a Simple Pressure Log

Note each visit: hornet count at the entrance, weather, whether foragers were flying, and any measures fitted. In ApiaryPilot you can add these observations to inspection notes and set follow-up tasks for re-checking entrances, so you can see which apiaries face the most pressure and compare seasons.

Common Mistakes

• Killing every large wasp. European hornets and other native insects are not the target.
• Hanging unselective traps all season. Bycatch can be considerable and rules may restrict it.
• Ignoring weak colonies. They are the first to collapse under sustained pressure.
• Trying to remove a nest. Leave it to trained services.
• Not reporting. Unreported sightings mean nearby nests stay active.

Your Next Field Action

On the next warm afternoon, spend ten minutes watching your entrances. Count hornets, note forager activity and photograph anything uncertain. If hornets are present, fit entrance protection, report the sighting with a flight direction, and check that each colony has the strength and stores to get through autumn.