Western Yellowjacket (Vespula pensylvanica)

Habits:

Western Yellowjackets will scavenge for protein and sugar, becoming "picnic pests". This species is known to create severe problems for loggers, fruit growers and outdoor recreational activities.

Nests:

The majority of Western Yellowjacket nests are found in abandoned rodent burrows, but have also been found in attics and building walls. Colonies range from 1000 to 5000 workers at peak size. In warmer climates, entire colonies can overwinter -- not just the queen.

Nature toward humans:

Western Yellowjackets are "picnic pests" and may be a hazard if agitated while scavenging. They are also a stinging hazard if the nest is disturbed. Western Yellowjackets can be very annoying to humans, since they are likely to be found near human activity.

Other Yellowjacket species

Paper Wasps

Hornets