Asian hornet colonies grow larger following record heatwave in France

The 2026 heatwave in France, recorded as the hottest summer on record with a national average of 24°C, has significantly impacted Asian hornet populations. While the extreme heat likely caused many small, young colonies to perish during the summer, it has also acted as a mechanism of natural selection. Experts report that the surviving colonies have grown into exceptionally large, “monster” nests.

In response to these large colonies, experts advise against using traditional bottle traps in September. By this time of year, the hornets have already established large secondary nests in trees or under roofs, and trapping individual workers does little to affect the core of the colony while potentially harming other beneficial insects like butterflies. Instead, observers are encouraged to monitor flight patterns to locate nests, but are warned not to attempt removal themselves.