Vespa-Watch

Report nests of Asian hornets

Image by Karel Schoonvaere

Vespa-Watch is the Flemish hotline for reporting nests of Asian hornets.

Your reports are useful for the monitoring and research of the species in Flanders. Reports of individual hornets are useful to locate nests.

In spring, one Asian hornet queen builds a new nest. This is the size of a ping-pong ball and can be found in a sheltered place, such as under a canopy or in a pen.

Report a nest or report an individual via waarnemingen.be or inaturalist.org.

Why are Asian hornets harmful?

The Asian hornet (Vespa velutina) is a wasp species from Southeast China. Since 2016, the species has also been present in Belgium. It is an ‘invasive alien species’:

  • The species did not originally occur here, but is now rapidly increasing in number and spreading throughout Flanders.
  • It attacks honey bees and other native insects that pollinate our flowers and plants.

More info on this page.

What can you see throughout the year?

  • In spring, one Asian hornet queen builds a new nest. This is the size of a ping-pong ball and can be found in a sheltered place, such as under a canopy or in a pen.
  • From June onwards, the first workers hatch and the nest grows further, to the size of a small football. Now you can start tracking nests using wickbait stations.
  • From August onwards, 70% of all nests move to higher places due to lack of space. A second nest is then built high in the top of a tree or on a facade. The entire colony moves to this second nest, and the first nest is abandoned.
  • At the end of summer, a nest can reach a diameter up to 1 m.
  • In autumn, nest Asian hornet nests become more visible.
  • In winter, drones and workers die. Only queens seek a wintering place. Exceptionally, you may encounter an Asian hornet queen inside your house, having awakened early. All nests are inactive, there are no hornets inside. They no longer need to be eradicated.

Cyclus

How do I recognize an Asian hornet?

See identification.

Where have Azian hornets been seen this year?

This map shows the hotspots and observations of the current season.

What to do when you got stung?

See the advise of the poison control center.

More questions?

See the FAQ.