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The lasting presence of the exotic insect is confirmed in Guin and Veveyse. The animal also arrives in Broye. Its proliferation seems inevitable.
Pest: The invasion of the Asian hornet has begun
Published on 06.05.2024
Estimated reading time: 5 minutes
It’s official, the Asian hornet has taken up residence in the canton. Witnesses observed and photographed him in Remaufens, in Veveyse, as well as in Guin, in Singine, on November 22. In mid-April, the presence of this exotic insect was again attested in the same localities.
“These repeated observations indicate the existence of nests in both regions. The Asian hornet seems to have established itself in the canton in a lasting manner,” notes Nicolas Fasel, scientific collaborator at the Forest and Nature Service of the canton of Fribourg. A first nest was discovered in 2022 in Montet, in Glâne.
Last week, the invader was also reported in Rueyres-les-Prés, in Broye. “This is a new front, but there has only been one sighting so far. This individual could also have been transported by truck along the A1 from the canton of Vaud or neighboring France, where the Asian hornet has been present for several years. In any case, Freiburg must now reckon with this dark hornet with yellow legs. No wonder, because the newcomer has been gradually colonizing the European continent since 2004.
“When hornets enter a hive, they can decimate the entire swarm”
Geneviève Gillon
This is bad news for beekeepers: the Asian hornet is harmful to bees, which it decimates to feed its offspring. “We already have varroa pressure and colony losses. The Asian hornet constitutes an additional threat to our apiaries,” laments Charles Oberson, president of the Friborg Beekeeping Federation, with 639 members.
Some beekeepers, fearing predator attacks, are beginning to equip themselves with protective mesh. The beekeeping supplies store La Butinerie, in Châtonnaye, offers original models, made by Sébastien Gillon. “They consist of wooden frames and a mesh with 0.7 millimeter mesh. It’s just big enough to let the bees pass through, but not the hornet,” explains Geneviève Gillon, co-founder of the store. This device does not prevent the hornet from attacking bees in flight, but keeps it away from the hive. “When hornets enter a hive, they can decimate the entire swarm.”
Danger in autumn
© Charly Rappo
The bees do not risk much in the spring, points out Xavier Gremaud, head of the task force against the Asian hornet set up by the Friborg Beekeeping Federation. “At the start of the season, it makes small nests close to the ground, often under shelters, and it finds enough food for the colony in spring. It’s in summer and autumn that things get bad: it then builds secondary nests. These colonies are usually found at the tops of trees, but can also be found close to the ground, in thickets. The largest nest found in the canton of Vaud contained more than 8,000 individuals in total, including more than 800 new queens. It takes a lot of food, and that’s when it attacks bees, which are easy and numerous prey for it.”
The federation appointed officials in each district section, who received a theoretical training course from the Swiss Bee Service for the fight against the invader (read below). “We will acquire equipment soon and we will train in September in direct interventions to destroy nests,” says the Gruérien. The fight consists of detecting the nests, then destroying them with an insecticide (or a non-polluting gas in a natural environment), with poles to reach the nests at height and suitable protective equipment.
Eradication excluded
There are no specific traps for the hornet: “It would be a serious mistake to set them because the traps also attract a host of other insects,” warns Nicolas Fasel. The aim of the efforts undertaken is not to eradicate the species. “We cannot avoid its installation. On the other hand, we can act to hinder its proliferation and reduce the pressure on the natural environment,” adds Xavier Gremaud. This is because the insect not only attacks honey bees, but also dozens of species of wild bees, butterflies and many species.
Does the Asian hornet pose a danger to biodiversity? “This is a very complex issue and there are few studies on the subject. In itself, the domestic bee is an imported species, and as such its presence is not neutral for local biodiversity either,” points out Nicolas Fasel. The Asian hornet does not present any particular danger to humans, being no more aggressive than the European hornet. The State of Friborg advises reporting the presence of the new insect in order to be able to follow its progress. “Observations must be reported on the national site: frelonasiatique.ch,” specifies Nicolas Fasel.
Beekeepers at the front with state support
Was the canton of Friborg too passive in the face of the arrival of the Asian hornet? Author of a question to the Grand Council in 2022, after a first observation of the beast in the Glâne, the Sarin MP Christian Clément (center) relayed the fears of beekeepers and was surprised that the State of Friborg had not anticipated the invasion.
But the time is no longer for criticism, and a dialogue has been established between the State of Friborg and the beekeepers. The Friborg Beekeeping Federation is responsible for training beekeepers and detecting nests in partnership with the Forest and Wildlife Service. The annual funding of 20,000 francs allocated since last year seems sufficient for the moment.
“We are really going to get into practical training this fall, by working directly on existing nests,” announces Xavier Gremaud, president of the Société d’apiculture de la Gruyère and head of the task force hornet. Interventions on the ground were not possible until now: while in 2023 more than a hundred nests were discovered in Geneva and around forty in the canton of Vaud, none were documented in the canton of Friborg before the reports from November 22. The question of financing the destruction of nests is still under discussion.
