Western Yellowjacket

Scientific name: 
Vespula pensylvanica
Size: 
12mm (body length)
Where found: 
In-ground nest, San Rafael

Western Yellowjackets typically form large, hidden colonies in enclosed spaces (especially in abandoned rodent burrows and occasionally in attics). When viewed from above, this species has a continuous yellow ring around each eye, and it is this feature that helps to separate them from other locally common yellowjacket species. Someone remarked that it appears that this species wears yellow "goggles". Western Yellowjackets hunt for a wide variety of prey (including but not limited to slugs, grasshoppers, spiders, flies and other insects) but will also scavenge for protein. These aggressive insects are commonly encountered in outdoor situations, especially where people are eating, and will defend their nest if disturbed. If the location of a ground nest is discovered, the Marin/Sonoma Mosquito & Vector Control District will eliminate the nest free of charge.  

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Western yellowjackets do not seem to understand or care that it is rude to show up uninvited to a picnic