“We have to live with it. This invasive species, whose population has skyrocketed, is impossible to eradicate. The activity has doubled compared to last year and not a day goes by without having to intervene in the home of an individual, a businessman…”, specifies Frédéric Demarbaix, who travels through Picardy Wallonia to eliminate the nests of wasps and other hornets.
At this time of year, activity is intense within Asian wasp colonies, which can reach 2,000 specimens per nest.
“This month of September is critical for bees because we are in a transition phase between the primary nests – very small in size built in spring in shelters by the young founding queens – and the current secondary nests. As the number of individuals is enormous currently, it can cause great damage if they manage to attack the hives,” explains the Leuze professional at the head of the company FDestruction, approved by the Region.
“Their behavior is constantly evolving”
The secondary nests, more imposing and spherical in shape, are generally found high in trees, more than 10 m away. “This was especially the case shortly after the arrival of the Asian hornets in Belgium, but for several years we have observed that they build their nests lower down, a few meters from the ground. We found them in children’s houses, in sheds of the garden, hedges… They realized that they did not have any natural predators here, apart from man. This makes the intervention more dangerous and complicated until the end of October.”
Their sturdy paper houses, patiently modeled from chewed wood fibers and then transformed into malleable paste by the queen and her workers, are true works of art.
Frédéric Demarbaix, who changed his firefighter uniform (25 years of service at the Leuze barracks) for a suit worthy of an astronaut, was able to prove it. The behaviors of these invasive and destructive insects evolve to adapt to those of citizens. “It is often said that Asian hornets like light, but sometimes they prefer dark places, such as attics.”
“They are increasingly common in our environment”: should we be worried about the increase in Asian hornets in Belgium?
Be careful when pruning your hedges
Although they are no more dangerous than wasps or their European counterparts, Asian specimens have a more aggressive defensive attitude to protect their nests or if they feel threatened.
“Just turning on a lawnmower, a chainsaw or hearing children screaming can provoke a hornet attack. They are very sensitive to vibrations. Another problem is that they move a lot in groups and each individual can sting several times. ‘directly’.
Allergic reactions resulting from its attacks should not be neglected in the most sensitive people. “This year, I have heard of three people who had to be hospitalized in the region. Among them, a resident of Ghislenghien who, without realizing it, cut off a nest of Asian wasps well hidden in his hedge”, specifies Frédéric Demarbaix, who asks citizens to be vigilant during this favorable period for garden maintenance work.
Do not risk trying to neutralize a nest without resorting to a private company or the firefighters (Editor’s note: the rescue zone does not charge for intervention if it involves Asian hornets).
How can we properly identify this species of the Hymenoptera family in comparison to the European wasp or hornet? “The Asian hornet has a blacker body with an orange band on the back and is smaller (3 cm) than the European one. This one looks more like a large wasp, with its yellow abdomen striped with black.”
These invaders have become pests in our country and it is becoming “illusory to eradicate”
The eastern hornet, a future threat
When we went to meet him, the professional from Leuze, protected from head to toe by a suit, gloves and glasses, was making life difficult for the hornets that had settled in a private walnut tree in Tourpes (Leuze).
With his ten-meter pole, he repeatedly pierced an imposing nest, 80 cm in diameter, containing about 1,500 individuals and larvae. “The injected product, an insecticide, is deposited almost everywhere in the cells and contaminates the nest. You have to wait two to three days for the entire colony to be affected.”
If hunting of Asian hornets continues in an attempt to limit their population, another threat arises… “We are probably not at the end of our problems. Within two or three years, the even more aggressive Eastern hornet, already present nearby Marseille could reach Belgium,” fears Demarbaix.
