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North American Animals - mamals, birds, reptiles, insects

 Western yellowjacket (Vespula pensylvanica)




Western yellowjacket | Vespula pensylvanica photo
Western yellowjacket (Vespula pensylvanica) on a fennel flower (Foeniculum vulgare), near Robber's Peak, Orange, CA, USA

Photograph by Davefoc. Some rights reserved.  (view image details)

Western yellowjacket | Vespula pensylvanica photo
Western yellowjacket (Vespula pensylvanica) on a fennel flower (Foeniculum vulgare)

Photograph by Davefoc. Some rights reserved.  (view image details)

Western yellowjacket | Vespula pensylvanica photo
Western Yellowjacket. Queen, San Jose, California, USA

Photograph by Eugene Zelenko. Some rights reserved.  (view image details)

WESTERN YELLOWJACKET FACTS

Description
The Western yellowjacket is a black and yellow wasp, and a serious insect pest species. The face is mostly yellow with narrow black bands in the centre and black on top of the head; the thorax is black and yellow; the abdomen is yellow with black bands which broaden to a triangular point in the centre. There is a black diamond shape on the first segment of the abdomen. This species usually builds its nest underground in old rodent burrows, but will also nest in wall and roof cavities. They often inhabit populated areas including parks and gardens and disturbance to the colony can result in stings. This species is also a scavenger and can be attracted where people are eating, for example at picnics. This is the most significant yellowjacket wasp pest in western North America, and is closely related to V. vulgaris.

Size
the queen is about 20mm, workers about 15mm

Environment
found in a variety of habitats including suburban areas

Food
Adult wasps prey on insects and other arthropods, and also scavenge for carrion.

Breeding
The queen wasp lays her eggs in the nest where they hatch into grub-like larvae. The larvae grow within the nest until they pupate, and after some time, emerge as adult wasps.

Range
Vespula pensylvanica is found in western United States from Washington to California and east to Montana, Colorado and New Mexico. It is also found in southern British Columbia and Alberta in Canada. It is also found in Mexico. It has also become established as an introduced species in Hawaii where it is also a nuisance.

Classification
Class:Insecta
Order:Hymenoptera
Family:Vespidae
Genus:Vespula
Species:pensylvanica
Common Name:Western yellowjacket


Relatives in same Genus
  Forest yellowjacket (V. acadica)
  Prairie yellowjacket (V. atropilosa)
  German yellowjacket (V. germanica)
  Eastern yellowjacket (V. maculifrons)
  Southern yellowjacket (V. squamosa)