In 2021, the Asian giant hornet was discovered in Marseille, leading to concerns about its invasive colonies disrupting Mediterranean regions. This hornet, larger than its relatives, displays distinctive coloring and has a diet primarily focused on insects, particularly bees. Unlike other hornets, it thrives in drier habitats and possesses remarkable alcohol tolerance, surviving high ethanol levels. Research continues on its ecological impact and effective methods for managing its population.
Introduction of the Asian Giant Hornet in France
In 2021, an alarming discovery was made when scientists first identified the Asian giant hornet in an industrial area of Marseille. Since its initial sighting, pinpointing its exact locations has proven challenging. However, entomologists have confirmed that numerous colonies of this invasive species are causing significant disruptions across various regions near the Mediterranean.
Characteristics and Behavior of the Asian Giant Hornet
This insect, a member of the Vespidae family, shares its lineage with both European and Asian hornets. Native to the Balkans and commonly found in southern Europe, it has been observed expanding its range toward the north due to climate changes. The Asian giant hornet can grow up to 3.5 cm in length, exhibiting a striking color palette that transitions from brown to red with rusty tones, while its abdomen is a vibrant yellow.
Similar to its Asian counterpart, the Asian giant hornet has a diet primarily consisting of insects and faces few natural predators. Researchers note that its venom is more potent, although it tends to be less aggressive towards humans, only approaching when threatened. This hornet is particularly known for its appetite for bees, consuming pollinators and raiding hives for honey.
While the Asian hornet prefers elevated nesting sites, the Asian giant hornet opts for drier habitats, often making its home in cavities or underground. The nests of this species are smaller and house fewer individuals, complicating efforts to locate them. Currently, scientists are still exploring effective natural trapping methods. If you encounter any of these hornets, please report your findings to the National Inventory of Natural Heritage (INPN) to aid ongoing research.
The Remarkable Alcohol Tolerance of Hornets
In nature, the decomposition of fruits, nectar, and other plant materials produces ethanol, which many animals utilize as a nutrient source. However, the consumption of alcohol can lead to intoxication, similar to its effects on humans.
Interestingly, the Asian giant hornet has demonstrated an extraordinary ability to tolerate high alcohol levels. Recent studies, highlighted by National Geographic, indicate that these hornets can withstand alcohol concentrations close to 80%, a level that would incapacitate most vertebrates, which typically can’t handle more than 4%. They utilize brewer’s yeast to survive harsh winter conditions, allowing them to reproduce within the bellies of wasps and hornets, providing them with essential energy during cold months. An Israeli study has revealed that hornets have evolved multiple copies of a gene that enhances their alcohol tolerance.
After consuming alcohol similar to absinthe, hornets may appear disoriented, struggling to fly or walk. “At one point, I saw several individuals lying on their backs. I was almost sure they were going to die, but when I came back to check on them a few minutes later, they were completely recovered,” recalls the study’s director, expressing his astonishment. Researchers also speculate that Asian giant hornets might leverage the antimicrobial properties of ethanol to maintain their health.