The Asian hornet: a danger for bees

The Asian hornet: a danger for bees

In Asia, the Asian hornet is known as a major enemy of apiaries because it is capable of destroying up to 30% of a colony of honey bees. In France, the attacks of this hornet continue to multiply, and beekeepers are worried. 

But who is this predator "the yellow-legged hornet"?

The arrival of the yellow-legged hornet

The Asian hornet, scientifically named "vespa velutina", is a species of hymenoptera native to Asia. It accidentally entered France in 2004: a queen nestled in a shipment of Chinese pottery bound for Lot et Garonne, France. All it took was one individual to cause the species to establish itself. 

The Asian hornet is endowed with an exponential reproduction mode and progresses in our territory of more than 60 km per year. This is how the species is present to date on three quarters of French territory, or in more than sixty departments. Its expansion also extends to Great Britain, Germany, Belgium, Portugal, as well as parts of Spain and Italy.

Massive and rapid invasion, the species was classified in 2013 as an "invasive alien species" under the French Environmental Code, in 2013.

Distribution du frelon asiatique en Europe (Source : INPI)

To see its annual progression, click here:https://bit.ly/2LH9GPK

How to recognize the Asian hornet

The Asian hornet is easy to recognize because it has many distinctions compared to the European hornet.

It is a very dark color, characterized by a black head, a black thorax, decorated with an orange ring on the abdomen and long yellow legs. It measures approximately 3 centimeters.

Conversely, the European hornet is of a larger size, and endowed with a body of a lighter color, stained with reddish, black and yellow.

Finally, the Asian hornet likes to fix its nest high in trees (at least 10 meters above the ground), unlike the European hornet.

Distinctions entre le frelon asiatique et le frelon européen

A dangerous predator?

The Asian hornet is not interested in humans, its favorite target is the bee, so it is quite possible to see it without harming you. It will only sting you if it feels threatened: if you attack its nest, or if you touch it. Its sting, although painful, is no more dangerous than that of the European hornet. People who are allergic to hymenoptera bites should of course remain vigilant.

On the other hand, the Asian hornet endangers biodiversity. Indeed, it feeds its larvae on flies, caterpillars and other pollinating insects such as bees and butterflies. However, it is these insects that ensure the survival of more than 80% of the plant areas listed on the planet thanks to pollination. The hornet thus disturbs the balance of nature.

Indeed, it is crazy about bees, whose thorax, rich in proteins, allows it to feed its larvae.

He has an attack strategy to capture them.

It locates its prey from a distance, using olfactory signals (it is very attracted by the smell of pollen), then positions itself in a hovering flight about twenty centimeters from the entrance of the hive, where it waits quietly whether its prey leaves the hive to forage, or returns with its harvest. He then pounces on her, and thanks to her larger size, he easily grabs her between her paws, and kills her with a blow of the mandibles behind her head. Finally he cuts it up because only the thorax will serve as food for the larvae.

In addition, waiting for long hours and often in large numbers (usually between 15 and 20 hornets watch a honeycomb) the Asian hornet stresses the foraging bees, who no longer dare to leave their hive to go and collect nectar and pollen. The presence of the Asian hornet thus plays a role in the disappearance of bees, as well as in the decline of honey harvests.

It is for these reasons that it was classified in 2012 as a "health hazard" for honey bees, under the Rural Code.

Frelons asiatiques autour d'une ruche d'abeilles domestiques

What to do if you meet an Asian hornet

  • Be still, ignore it, and slowly walk away. He won't be aggressive until you tackle him.
  • If there is a nest, call the firefighters, so that they can analyze the danger of it and find a way to eradicate it.
  • Report the presence of an individual or a nest of Asian hornets to the French Heritage Inventory (INPI): http://frelonasiaque.mnhn.fr/signaler-informations/ (Be careful not to confuse it with another Hymenoptera).
  • In case of sting, disinfect the wound well, pass an ice cube to reduce the swelling, and relieve the pain. If you have difficulty breathing, or if you feel unwell, call for help.

Note: The Asian Hornet's stinger can pierce through thick fabric, such as clothing, and it is also able to spray its venom from a distance!

Stay alert.