This yellowjacket is not a species native to California, but has become established in some areas. Adults are scavengers and predators of other insects. They build nests in hollow walls, attics and sometimes in aerial locations. Nests constructed inside walls can cause damage to the interior of a home and can result in adult yellowjackets inside the house. Nests contain 500 to 5,000 workers and start to decline sometime between late September and December.

A species of yellowjacket native to Europe which has been found in parts of California in the last few years. Nests can be found in the ground or in man-made structures. Colonies can be quite large with as many as 5,000 active workers at any one time. Adults utilize a wide range of arthropods, especially insects such as flies as hosts and are easily attracted to sweets. This species can be a pest to beekeepers and problematic in parks and marketplace areas. Adults can forage up to 1600 ft. from their nests.

Adult Activity Period: March – November