Biologically, the Asian hornet is a social insect living in colonies organized around a founding queen, workers, and, at the end of the season, males and future queens. As with many hymenoptera, the colony's survival depends on fine coordination between individuals, made possible by highly effective communication methods .
To function coherently, an Asian hornet colony relies on various communication systems. These mechanisms allow it to coordinate foraging, nest defense, reproduction, and collective behaviors. The two main modes of communication observed in Vespa velutina are pheromones (chemical signals) and visual and behavioral signals .
Pheromones play a central role in the life of the Asian hornet. These are specific chemical substances released by individuals to transmit information to other members of the colony. Each type of pheromone corresponds to a precise message, instinctively understood by other members of the colony.
The queen notably produces pheromones known as recognition and social regulation pheromones , which help maintain colony cohesion and inhibit worker reproduction. This mechanism ensures that only the queen lays eggs, which is essential for the social organization of the species.
The worker hornets, for their part, use alarm pheromones when they perceive a threat near the nest, such as the presence of a predator, a human, or an attempt to destroy the nest. These chemical signals spread rapidly through the air and trigger a collective defense response. This explains why approaching an Asian hornet nest can provoke a coordinated attack by several individuals within seconds.
Pheromones also play a role in foraging. When a worker bee identifies an interesting food source, it can help attract other individuals to the area, thus increasing the effectiveness of collective predation, particularly around beehives.
In addition to chemical communication, the Asian hornet uses visual signals and specific behaviors to communicate within the group. These signals are particularly visible during hunting and predation phases.
The behavior of circling or hovering in front of a target, such as a beehive, a group of insects, or an area rich in prey, constitutes a form of visual marking. This behavior allows the hornet to track the flight paths of prey and facilitate their capture. It can also serve as a signal to attract the attention of other hornets nearby, indicating that a food source is available.
Rapid movements, sudden changes of direction, and certain flight postures also contribute to communication between individuals. These behavioral signals allow hornets to coordinate their movements in space , particularly during group hunting or nest defense. In complex environments, such as hedgerows, orchards, or wooded areas, these visual signals effectively complement the information conveyed by pheromones.
The combination of pheromones and visual signals gives the Asian hornet a highly efficient organizational capacity . This multimodal communication allows the colony to act in a coordinated manner, whether to locate food resources, defend the nest against a threat, or optimize predation around beehives.
This collective efficiency partly explains the significant impact of the Asian hornet on bee populations and local biodiversity. It also highlights why controlling this invasive species is complex: the cohesion and responsiveness of the colony make interventions delicate, especially when a nest is disturbed.
Hornet EcoTrap selective traps allow you to capture founding queens before they establish a new colony in early spring.
