Asian hornet (Vespa velutina)

Size:

• Queen: 28–30 mm
• Worker female: 28–30 mm
• Drones: ~24 mm

Look:

• Black coloration with very little yellow content
• No drawing on the head shield
• Temples dyed black
• Eye socket colored orange to reddish-brown

Life cycle:

• One-year colony (March–November)
• The queen hibernates and founds a new colony in the spring.

Nest:

• Nest locations for the first nest: Hollow trees and shrubs between 1-2 meters high
• Nesting sites for the second nest: trees or buildings at heights of approximately 10 meters.
• Nest size: 1,000–2,500 individuals (4,000–10,000 under optimal conditions)
• Nest made of rotten wood, beige-brown

Nutrition:

• Larvae: Protein-rich food (insects, meat)
• Adults: Carbohydrates (sugar, nectar, fruit)

Behave:

• Social: Clear division of labor (queen, workers, drones)
• Hardly aggressive, even near the nest
• Pollination and pest control

Painful stings:

• The stings of the Asian hornet are painful and can cause local reactions such as swelling, redness and severe itching.
• Unlike bees, hornets can sting multiple times because their stinger does not remain stuck in the skin.

Allergic reactions:

• Hornet stings can trigger severe allergic reactions (anaphylaxis) in sensitive individuals, which can be life-threatening.
• Typical symptoms: shortness of breath, dizziness, rapid heartbeat, widespread swelling, especially in the face or airways.
• People with known allergies should always carry an emergency kit (e.g., an adrenaline auto-injector).

Toxic effects:

• The sting injects a toxin containing histamine and other irritating substances that can damage tissue and cause pain.
• Multiple stings at the same time can trigger toxic reactions, especially dangerous for children, the elderly, or people with weakened health.

Aggressive behavior:

• The Asian hornet defends its nest extremely aggressively and often attacks in groups when a threat is perceived.
• A single attack can alert other Asian hornets through released pheromones and trigger a coordinated defense.

Disease transmission:

• No relevant disease transmissions

Food:

• Always cover food and drinks when outdoors, especially meat and sweets.
• Dispose of food scraps and waste in sealable containers.

Hygiene:

• Do not leave open garbage cans or bags.

House and garden:

• Seal cracks, crevices and potential nesting sites on houses.
• Install insect screens on windows and doors.

Behave:

• Avoid sudden movements or blowing on hornets, as this will trigger aggressive behavior.
• Keep your distance from nests and do not remove nests yourself – consult professional pest control experts.

Garden maintenance:

• Empty water sources (e.g., plant pots) regularly, as hornets use them to cool their nests.
• Regularly collect fallen fruit in the garden.