The Asian hornet: what every Dutch beekeeper needs to know now

For a long time we were warned he was coming. In 2017 he was first spotted in the Netherlands. By now the Vespa velutina nigrithorax has been confirmed in multiple provinces and nests have been found from Limburg to Drenthe. For beekeepers, this is no longer an abstract news item. It is a question of when, not if.

In this article I summarise what you need to know: how to recognise him, what he does to your bees, how to find a nest, and what you can already do at your apiary. Plus: how to report him, and why you absolutely should not try to destroy him yourself.

How do you recognise him? (Asian vs European)


This is where most confusion lies. The Asian hornet is a different species from the 'common' European hornet (Vespa crabro). Many people see a large wasp and immediately think it is an Asian one, when it is European. Or the other way around.

Asian hornet (Vespa velutina):

• Length: 2 to 3 cm (workers)
• Body: predominantly black or dark brown
• Abdomen: mostly black, with one yellow band (fourth segment)
• Head: orange from the front
• Legs: black with bright yellow tips ('yellow socks'), the most recognisable feature
• Sound: lower and heavier than a regular wasp

European hornet (Vespa crabro):

• Length: 2 to 3.5 cm (workers), queen up to 4 cm
• Body: mostly brown with yellow
• Abdomen: more yellow with brown bands
• Head: brown/yellow
• Legs: brown, no 'yellow socks'
• To bees: much less threatening than his Asian cousin

If you ever encounter an Asian hornet: take a photo. You need a good photo for the NVWA report.

Why is he a problem for your bees?

The Asian hornet has a unique hunting technique that makes him so dangerous to honey bees: he hovers in front of the entrance of your hive, sometimes for hours on end, and grabs returning forager bees out of the air. One hornet can catch 30 to 50 bees per day. With multiple hornets per hive, this quickly rises to hundreds of bees per day.

The second effect is perhaps even worse: paralysis stress. Bees that see hornets hovering in front of the entrance no longer dare to fly out. They stop foraging. The colony shrinks, stores run out, and a heavily affected hive can collapse within weeks.

In France, where the Asian hornet has been present since 2004, beekeepers in heavily affected areas report up to 30 to 80% colony losses in bad years. The Netherlands is not at that point yet. What you do now helps determine whether we get there.

The nest: primary vs secondary

An Asian hornet colony makes two nests in one season. This is important to know because it determines where you will search.

Primary nest (April to June):

• Small: from ping-pong ball to grapefruit size
• Low: often in a shed, under a gutter, in a garden house, garage
• Built by one queen, so still vulnerable
• Best moment to report and destroy

Secondary nest (June to October):

• Large: up to 60 to 80 cm diameter
• High: usually 10 to 30 metres up in a tree, often in the crown
• Contains hundreds to thousands of hornets
• Visible when leaves fall, but by then the season is practically over

It is much easier to find a primary nest in May than a nest 25 metres up in a tree in July. So in spring, keep a close eye on your shed, garden house, bird boxes and gutters for a small grey papery ball.

💡 Personal experience: I have personally spotted several in my area by now. What stuck with me most: we went out as a small group specifically to look for them, caught one, and equipped that hornet with a small transmitter. The little creature was released and flew straight back to its nest, with us in its wake. Sounds like CSI, but it is just beekeeping anno 2026. For secondary nests high in trees, this is honestly often the only workable method. Ask at your association or in your region whether there are groups doing this, and join them.

What do you do when you see an Asian hornet?

Step 1: report it. This is the most important thing. Without reports, the NVWA cannot coordinate anything, and the species keeps expanding unnoticed.

Report via:

• waarneming.nl (fastest route, for everyone)
• vespa-watch.nl (specifically for the Asian hornet)
• Directly to the NVWA at 0900-0388 (for nests and major finds)

Include at minimum:

• Photo of the hornet (from above, sharp, 'yellow socks' visible)
• Date and time
• Exact location (GPS pin)
• What the creature was doing (on a flower, flying, found dead?)

Step 2: catch one. Sounds scary, but an Asian hornet sitting on a flower can be caught in a jar by placing the jar over it. Put it in the freezer briefly, and you have a specimen for identification and possible DNA analysis by experts.

Step 3: do NOT destroy it yourself. You hear this often, but it is genuinely important. Attacking a nest without professional protection can lead to hundreds of stings in seconds. Asian hornets are extremely defensive near their nest, and their venom is stronger than that of regular wasps. In France there have been deaths due to amateur attempts. Leave this to trained exterminators (your municipality or the NVWA arranges this).

What can you do for your hives?

Here it becomes concrete. You cannot prevent hornets from finding your apiary, but you can make it significantly harder for them.

1. Reduce the entrance. In late summer, reduce the entrance to a slit of maximum 5.5 mm high. Bees can still pass through, hornets cannot. The simplest and cheapest measure.

2. Guide your bees. Place a light-coloured panel (white linen, wood) 2 to 3 metres in front of the hive. Hornets will tend to hover there, and bees will fly underneath back to the hive. Helps less than you hope, but every bit counts.

3. Electric harp. An electronic grid in front of the entrance: bees fly through unhindered, hornets get electrocuted. Costs between €100 and €300, proven effective in France. For those with heavy infestation, the most concrete weapon.

4. Bait traps, with major caveats. In spring (March to May) some beekeepers hang bait traps with beer or sugar water to catch queens. Problem: you also catch tens of thousands of other insects, including butterflies, ladybugs and regular wasps that are not a problem. My advice: only do this if there is a confirmed nest in your direct vicinity, and always use selective traps (Vespacatch and the like) with an exit for small insects.

5. Keep strong colonies. A weak colony succumbs to hornet stress sooner than a strong one. Sounds simple but it is true: good varroa control, sufficient winter stores, healthy queen. Hornets seek the weakest target.

💡 Honest confession: I have not yet adapted my own hives. It is on my list, but I still need to figure out which measure delivers the most for my situation. Reducing the entrance in late summer is something any beekeeper can do, and I will certainly do that. Whether I will invest in an electric grid I do not know yet. If you have experience with a specific approach: share it on the forum. This is the kind of topic where we learn more from each other's practical experience than from any leaflet.

What you should especially not do

• Do not attack a nest yourself with pesticide or poison
• Do not try to destroy a nest with water or fire
• Do not run away from every large wasp you meet without checking
• Do not panic-clear all nests in your garden, European hornets are protected and beneficial

What you should do: stay calm, take a photo, report it, and reduce your entrance in late summer.

What we (still) do not know

I try to be honest in these articles about what is uncertain.

• We do not know whether the Dutch population will ever become as dense as in southern France. Climate, landscape and control measures can heavily influence the trajectory.
• We do not know what the long-term effect on the Dutch beekeeping population will be. Optimists say: we will learn to live with the hornet as we learned to live with varroa. Pessimists say: it will get worse than we think.
• We do not know with certainty which defence measures work best in our conditions. French research does not always translate one-to-one.

What we do know: early reporting and signalling is the most valuable thing individual beekeepers can do right now.

Finally

The Asian hornet is no longer something to point to as a 'southern French problem'. He is in the Netherlands, he stays in the Netherlands, and as a beekeeper you will probably have to deal with him in the next five years, or you already are.

The good news: research into effective control has been running for years in France and Belgium. The NVWA is actively monitoring. Many beekeeping associations organise info evenings. Use them. A local beekeeper with experience teaches you more than any French research could.

Have you reported an Asian hornet? Found a nest? Got a defence trick that works? Share it in the forum under Bee Health & Diseases, that is exactly where this knowledge belongs.

🐝 Good luck and keep reporting.