Behavioral responses of honey bees, Apis cerana and Apis mellifera, to Vespa mandarinia marking and alarm pheromones

The giant hornet, Vespa mandarinia is a predator of honey bees throughout its range in eastern Asia. The hornets’ behaviors are coordinated through pheromones; a marking pheromone is used to mark honey bee nests as a food source, and an alarm pheromone, comprised of three chemical components of their venom, is released when a hornet is attacked by honey bees. The Asian honey bee Apis cerana evolved in sympatry with the giant hornet. In contrast, the European honey bee, Apis mellifera and V. mandarinia evolved in allopatry, although A. mellifera colonies have been introduced within the hornet’s range. We investigated the responses of these two honey bee species to the V. mandarinia marking pheromone, two alarm pheromone chemicals individually, and the three alarm pheromone chemicals together. We applied these substances above hive entrances and photographically monitored pre- and post-treatment numbers of bees on the exterior of the hive near the entrance. A. cerana colonies responded to the marking pherom...