The Asian giant hornet, Vespa mandarinia, is the world’s largest hornet. It measures up to 45 millimeters (1.75 inches) in body length, with a wingspan reaching around 75 millimeters (3 inches). Its imposing size and ability to rapidly decimate honeybee colonies earned it the “murder hornet” moniker in popular media. The hornet possesses a 6-millimeter (0.25 inch) stinger capable of delivering potent venom.
Native Geographical Range
The Vespa mandarinia is indigenous to a broad expanse across Asia, thriving in temperate and tropical regions. Its natural distribution encompasses East Asia, South Asia, mainland Southeast Asia, and parts of the Russian Far East. Countries in its native range include Japan, China, Korea, parts of India, Nepal, Vietnam, Thailand, Malaysia, Pakistan, and Taiwan. This hornet is well-adapted to areas between temperate and tropical zones, favoring lowlands over high elevations.
Within these native ecosystems, Vespa mandarinia functions as a predator, feeding on various insects and occasionally small rodents. Local species, such as the Japanese honeybee (Apis cerana), have developed defense mechanisms, like collectively heating the hornets, to protect their colonies. The hornet is a common component of these environments, and its habitats do not typically require conservation efforts due to its widespread presence.
Invasive Presence and Spread
Vespa mandarinia outside its native range garnered considerable attention, particularly in North America. The first confirmed sightings occurred in 2019, concentrated in British Columbia, Canada, and Whatcom County, Washington. An initial nest was found and eradicated in Nanaimo, Vancouver Island, in August 2019, with detections in Blaine, Washington, in December of the same year. Genetic evidence from these separate initial introductions suggested distinct origins, with populations in British Columbia potentially from Japan and those in Washington from South Korea.
The hornet’s appearance in new territories raised concerns due to its capacity to devastate honeybee hives, sometimes within hours. Local and federal agencies launched extensive efforts to track and eradicate the invasive populations. By the end of 2021, authorities in Washington State had located and destroyed four nests. Following three consecutive years without confirmed detections, the Washington State Department of Agriculture and the United States Department of Agriculture declared Vespa mandarinia eradicated from Washington and the entire United States in December 2024.
Preferred Habitats and Nests
Vespa mandarinia prefers specific environments for nesting. These hornets typically inhabit low mountains and forested areas, generally avoiding open plains and high-altitude climates. They are primarily forest dwellers and often associate with green spaces, even in urban landscapes. Their nests are almost exclusively subterranean, frequently constructed by digging or utilizing pre-existing cavities.
Common nesting sites include abandoned rodent burrows, spaces near rotten pine roots, and hollow logs. While most nests are underground, they can also be found in tree hollows or occasionally in urban structures. The depth of these underground nests can vary, ranging from 6 to 60 centimeters (2.4 to 23.6 inches) below the surface. Adult hornets consume sugar-rich liquids like tree sap and honey, while their larvae are fed a protein-rich paste derived from other insects. Hornets travel several kilometers from their nests to forage for food.