Asian Giant Hornet

Asian Giant Hornet (Vespa mandarinia), is the world’s largest hornet, measuring up to 2 inches long. Despite its large size and distinctive markings, people often confuse it for other species.

Body length

• From 1.5 to 2 inches

Coloration

• Head: Large and solid yellow or orange, with black eyes
• Thorax: Mostly solid dark brown or black, making a striking contrast with the head color
• Abdomen: Alternating bands of dark brown or black and yellow or orange

AGH adults have a “wasp waist” between the thorax and abdomen.

Lookalikes

Western cicada killer (Sphecius grandis)

[USDA Photo by Hanna Royals]

• Found in the western United States
• Can be up to 2 inches long
• Has a smaller head in proportion to the body than AGH, and different banding on the abdomen
• Has a reddish thorax instead of black, like the AGH
• Unlike hornets, has round eyes

Note: The contrast between the head color and the thorax color is much more apparent in AGH than in cicada killers.

Eastern cicada killer (Sphecius speciosus)

[USDA Photo by Hanna Royals]

• Found in the East and Midwest
• Can be up to 2 inches long
• Has a smaller head in proportion to the bodies than AGH, and different banding on the abdomen
• Has a reddish thorax instead of black, like the AGH
• Unlike hornets, has round eyes

Note: The contrast between the head color and the thorax color is much more apparent in AGH than in cicada killers.

Various species of yellowjackets (Vespula spp.)

[USDA Photo by Hanna Royals]

• Different species found throughout the United States
• Grow to about .5 inches long (workers), significantly smaller than AGH
• Often are more brightly marked with yellow or orange and black than the AGH

Great golden digger wasp (Sphex ichneumoneus)

[USDA Photo by Hanna Royals]

• Found throughout much of North America
• Is about 1 inch long
• Has a “wasp waist” that is very narrow and long
• Has a dark brown to black body, with orange to yellow legs
• Has an abdomen that is black with solid orange/red toward the front end, with no banding like the AGH
• Has golden hairs covering the head and middle of the body, making this species distinctive

European hornet (Vespa crabro)

[USDA Photo by Hanna Royals]

Note: Does not occur west of the Rocky Mountains.

• Found in the eastern United States, especially in the southeast
• Ranges in size from 1 to 1.5 inches long, usually around half the size of an AGH
• Has marking that can vary, but appears to have “teardrops” of brown to black on the primarily yellow abdomen (the AGH has more uniform bands)
• Has a dark band on the front of the abdomen right after the “wasp waist,” unlike the yellow band in the AGH

Elm sawfly (Cimbex Americana)

[USDA Photo by Hanna Royals]

• Found throughout much of North America
• Ranges in size from .75 to 1 inch long
• Lacks a “wasp waist” between the thorax and abdomen (unlike the AGH)
• Has a white or yellow spot on the thorax
• Is the largest sawfly on the continent

Note: Females may be yellow, more resembling a wasp.

Various species of paper wasp (Polistes spp.)

[USDA Photo by Hanna Royals]

• Found throughout North America
• Can grow to about.75 inches long, significantly smaller than the AGH

Note: Most paper wasps have a well-defined “wasp waist” that separates them from other hornets.

Bald-faced hornet (Dolichovespula maculata)

[USDA Photo by Hanna Royals]

• Found throughout much of North America, but most commonly in the southeastern United States
• Ranges in length from .5 to .75 inches, although they are usually slightly larger than yellowjackets
• Can be identified by their mostly black abdomen with white markings

Pigeon tremex (Tremex Columba)

[USDA Photo by Hanna Royals]

• Distributed widely in eastern North America, ranging as far west as Utah and Arizona
• Can be up to 2 inches long
• Lacks a “wasp waist” between the thorax and abdomen, unlike the AGH

Yellow bumblebee (Bombus fervidus)

[USDA Photo by Hanna Royals]

• Found throughout much of the western and northeastern United States
• Has black coloring with yellow stripes
• Grows to about .5 inch long (for workers)
• Has a very stout body

Note: Bumblebees can be separated from wasps and hornets because their bodies are covered in hairs and appear “fuzzy,” and they have a structure for gathering pollen on their hind legs.

European honey bee (Apis mellifera)

[USDA Photo by Hanna Royals]

• Found in every state
• Grows to about .5 inch long (workers)
• Has reddish-brown coloring (this can vary depending on the race)
• Has dark bands on the abdomen, as well as a structure for gathering pollen on their hind legs

Spring: A fertilized queen emerges after surviving the winter. She enters a brief pre-nesting stage. The queen feeds on sap, develops her ovaries, and looks for a suitable nesting site. She usually nests in preexisting underground cavities with a narrow opening, such as rodent burrows. 

Summer: Once the queen selects a suitable site, she enters a solitary phase. During this time, she alone is responsible for building a nest, foraging, laying eggs, and caring for young. When around 40 workers are in the nest, the colony enters a new phase. The queen becomes completely nest-bound, and the workers assume all duties outside of the nest. 

Late Summer/Early Fall: When there are many workers, the colony begins producing males and the next year’s queens. Workers feed these new “reproductives” within the nest because reproductives do not forage. To obtain food with higher protein, AGHs may attack honey bee hives in the late summer/early fall. The hornets kill all of the adult bees and leave them at the bottom of the hive. Then the hornets remove the hive’s brood, taking bee larvae and pupae back to their nests. AGHs may attack other social bees and wasps at this time. 

Fall: Males develop and leave the nest before females. They will perch at the entrance of nests waiting to mate with the new queens, which emerge about 1 month later. New queens must mate before overwintering because males will not be present when the queens emerge the following spring.

Winter: After mating, a new queen will spend the colder months overwintering in a sheltered spot she has excavated in the soil, rotting wood, or piles of straw. The cycle begins again the following spring when the new queens emerge from overwintering.

AGH does not attack people unless it feels threatened. An AGH’s stinger is longer than that of bees or wasps found in the United States, and their venom is more toxic. People with an allergy to bee or wasp stings should take particular caution and calmly leave the area if they believe they have sighted an AGH. More information about AGH and human health can be found at https://agr.wa.gov/departments/insects-pests-and-weeds/insects/hornets/human-health.

In Washington State only, people should report potential sightings of the AGH through the Washington State Department of Agriculture’s website. Outside of Washington, contact your state apiary inspector. If it is safe to do so, take a photo or collect a dead specimen of the pest to help experts identify the insect.

All photographs in the “Asian Giant Hornet and Lookalikes” are the products of PPQ’s Identification Technology Program (ITP). Colorado State University’s C. P. Gillette Museum of Arthropod Diversity provided the specimens.

ITP’s pest identification experts use high-technology imaging systems, software, and molecular diagnostics to create a wide array of digital and other identification tools. Visit idtools.org to browse their extensive pest identification resources. 

If you are interested in pollinator health, you may find these two ITP identification resources useful:

• Bee Mite ID Guide
• Exotic Bee ID guide