German Yellowjacket

Vespula germanica (Fabricius), an invasive Palearctic species now widespread globally, is a social wasp in the family Vespidae. Queens are typically 18-20 mm long, and workers are 12-16 mm. Distinctive features include strong black and yellow markings, with a characteristic anchor-shaped black mark on the clypeus (face) and a series of black spots on the abdomen that are often confluent. Nests are constructed from chewed wood fibers, forming multiple tiers of combs enclosed in a paper envelope, usually in concealed locations. An overwintering queen establishes the colony in spring.

German yellowjackets are both predatory and scavengers. They hunt a variety of insects to feed their larvae but are also highly attracted to human foods, particularly sweets and proteins, making them a significant nuisance pest in outdoor dining areas. They are highly aggressive and will sting repeatedly if their nest is threatened or disturbed. Colonies can become very populous by late summer, increasing the likelihood of human-robot encounters. Foraging activity is extensive, with workers traveling considerable distances.