The Asian Giant Hornet (Vespa mandarinia) is the largest hornet species in the world, with queens reaching up to two inches in length and a wingspan of about three inches. This imposing insect, native to temperate and tropical regions of East Asia, has garnered significant public attention due to its predatory habits. The hornet’s diet varies significantly between adult individuals and the developing colony, reflecting distinct nutritional requirements.
Adult Hornet Diet
Adult Asian Giant Hornets primarily consume sugary liquids to fuel their high metabolic rates. These energetic substances include tree sap, ripe fruits, and floral nectar. Hornets will also forage for honey from bee colonies to meet these carbohydrate needs. For instance, queens emerging from hibernation in spring often feed on tree sap while searching for nesting sites. Unlike their larvae, adult hornets are unable to digest solid protein, relying instead on liquid nutrition for their own sustenance.
Food for the Colony
The nutritional demands of the developing hornet larvae largely drive the Asian Giant Hornet’s predatory behavior. Larvae require a protein-rich diet for growth, which adult worker hornets provide by hunting other insects. Their prey includes a variety of medium to large insects, such as beetles, mantises, and other wasp species. Honey bees, both the European honey bee (Apis mellifera) and the Asian honey bee (Apis cerana), are common targets. Workers capture prey, chew it into a protein-rich paste, and bring it back to the nest to feed the growing larvae. In return, the larvae secrete a clear, amino acid-rich liquid that the adult hornets consume, completing a reciprocal feeding relationship known as trophallaxis.
Hunting and Foraging Methods
Asian Giant Hornets employ sophisticated strategies to acquire their diverse diet. For sugary substances, they locate sap flows on trees or find ripe, fallen fruits. They can also collect honey from raided bee nests, which serves as an additional energy source. Their predatory hunting techniques for insects, particularly social insects like bees, are highly organized.
A single scout hornet first locates a bee colony and may chemically mark the hive entrance with a pheromone to guide nestmates. This initial “hunting phase” involves individual hornets capturing bees near the hive entrance. If the hornet nest is close to the prey colony, this can escalate into a “slaughter phase,” where multiple hornets launch a mass attack, killing thousands of adult bees within hours. During this phase, hornets often decapitate the adult bees.
Following the slaughter, the hornets enter an “occupation phase,” where they collect bee larvae and pupae, which are rich in protein, to transport back to their own nest for their developing young. They dismember their prey, often returning only the most nutrient-rich body parts, such as flight muscles, to the nest.