Municipal authorities across Ixelles are sounding the alarm as the invasive Asian hornet returns with force this spring, raising fresh concerns for biodiversity, beekeepers and public safety.
Present in Belgium since 2010, the Asian hornet, Vespa velutina, has steadily expanded its range. The species preys aggressively on honey bees and other pollinators, contributing to declining bee populations and threatening fragile ecosystems.
Local officials warn that the coming weeks are critical. Spring marks the period when fertilised queens emerge from winter hibernation and begin constructing new nests that will later house hundreds, sometimes thousands, of hornets.
“The coming weeks are decisive if we want to significantly reduce its spread this season,” said Climate Councillor Valérie Libert, urging residents to act early by installing traps designed to capture queens before colonies form.
According to the commune, Asian hornets had a noticeable impact on beehives placed at the Ixelles Cemetery last year. Entire colonies were weakened or wiped out after repeated attacks near hive entrances.
Animal Welfare Councillor Nathalie Gilson said each captured queen represents a significant victory. “Every queen captured means one entire Asian hornet nest fewer — and therefore thousands of bees and other insects essential to our biodiversity protected,” she explained.
The threat appears to be growing nationwide. Sightings in Belgian gardens nearly doubled last year, with almost 8,000 reports logged through Waarnemingen.be, the Flemish citizen science observatory that tracks wildlife data.
Originally from Southeast China, the hornets have spread rapidly across Western Europe. Experts say the absence of natural predators in Belgium allows populations to grow almost unchecked once nests are established.
Asian hornets hunt in coordinated groups, often hovering in front of beehives to catch returning bees mid-flight. Beekeepers describe scenes where dozens of hornets wait outside hive entrances, exhausting the colony and reducing pollination activity.
A recent COLOSS survey found that about 18 percent of Belgian beekeepers have seen hornets enter their hives, while nearly one in ten reported discovering empty colonies after attacks.
During spring and early summer, queens build small “primary nests” close to the ground, hidden in hedges, sheds or shrubs. These nests later expand into larger secondary colonies, sometimes high in trees, making them harder to remove.
Environmental groups are stepping up awareness campaigns. Last year, Apis Bruoc Sella, a Brussels-based environmental and apiculture association, issued updated guidelines to park workers and gardeners on how to identify concealed nests safely.
The organisation also stressed that the public should never attempt to destroy a nest themselves, as disturbed hornets can become highly aggressive and attack in swarms.
Health risks are also a concern. Several people were hospitalised last year after suffering multiple stings. Authorities note that allergic reactions can quickly become life-threatening and require immediate emergency assistance.
To tackle the problem proactively, Ixelles has partnered with cleaning services company Groupe F to distribute specially designed selective traps to residents. These traps allow smaller insects to escape while capturing the slightly smaller Asian hornets.
Officials emphasise that the devices do not harm native species such as the European hornet, which plays an important ecological role and is too large to enter the trap openings.
Public information sessions are being held to show residents how and where to place the traps effectively. At a recent community meeting, dozens of locals collected free equipment and learned how to report sightings.
The campaign is not limited to Ixelles. The City of Brussels has organised similar sessions earlier this month, while Watermael-Boitsfort plans its own spring trapping drive and information day in mid-March.
Residents who discover a nest are urged to keep their distance and notify authorities through official reporting platforms rather than intervening themselves. In emergencies involving multiple stings or allergic reactions, calling 112 remains the recommended course of action.
For beekeepers like those in Ixelles, the stakes are high. Bees are responsible for pollinating a vast share of food crops and flowering plants. Losing colonies means not only economic losses but wider ecological consequences.
As warmer weather sets in, officials hope early intervention will prevent a repeat of last year’s spike in sightings. By targeting queens now, municipalities aim to break the reproductive cycle before thousands more hornets take to the skies.
With free traps still available at local communes, authorities say community participation could make the difference between containment and another season of unchecked spread.
