Dolichovespula arenaria
aerial yellowjacket
(Also: yellow jacket)

Throughout North America as far north as the Arctic Circle

Yellowjackets are eusocial and have an established caste system similar to that of honey bees. A division of labor places the queen as the single reproductive element of the colony. She begins by constructing a small nest, laying a series of eggs that will become sterile workers when they mature. These workers help her in expanding the colony by enlarging the nest and collecting food for successive generations. Sterile female workers also care for the young by capping off their individual cells to serve as pupal chambers. As the nest becomes larger and greater amounts of food are brought in, larger females are produced. These are the potential queens of future colonies. Finally, the queen produces haploid males, whose sex she can controls by preventing her eggs from being fertilized. The fertilized females hibernate through the winter, while the rest of the colony dies off in cold temperatures. The sterile offspring are much smaller than the queen. Yellowjackets use their sting mainly in defense of the colony.

Adults commonly feed on nectar and the jucies of ripe fruits. Workers prey upon smaller insects, such as caterpillars, and feed the macerated insects to the larvae of the colony. Adult mouthparts are designed for chewing, catching, and sucking.

Chewing and sucking of fruits meant for human use causes crop loses. They take parts of domestic plants for the construction of the nest. Can cause serious injury to humans with sting. Can transmit a disease called Fire Blight to potato crops.

Yellowjackets are predators of some insects which are harmful to domesticated plants. They have been used in the biological control of other pest species. They also aid in the production of some fruits by pollinating the flowers. Behavior and sociobiology of some "higher animals" have been studied using yellowjackets as a guide.

This species is abundant and successful thoughout its range.

The outer walls of the nest and the individual cells for the larvae are made of a mixture of wood and saliva. This creates a layer of protection. Within it, yellowjackets are able to regulate the temperature of their environment by fanning their wings. Nests are usually subterranean or near to the ground and contain 1000-4000 workers.