Sphecidae: Thread-waisted Wasps

Biology

Sphecids are medium to large solitary digging wasps with about 54 species in our region.  They are an extremely diverse group of hunters with great variation in body size and form.  They are frequent visitors to flowers but are also valuable in the home garden as predators of other (often pestiferous) insects.  Adults feed on nectar, honeydew and the body fluids of their prey.  There are many species ranging in size from ½ to 1 ½ inches belonging to a number of genera and each specializes in the kind of insect it hunts and preys on.  Some prey only on spiders, others on grasshoppers, beetles, katydids, or caterpillars.  Prey is paralyzed by the wasp and taken back to a nest dug into the ground and placed within it.  An egg is laid on the prey insect which provides food for the developing larva.  Hunting wasps may be large and appear quite fearsome but they are a definite asset to pest control in the home garden.

The Great golden digger wasp, (Spex ichneumoneus) is a large non-aggressive sphecid common in the Pacific Northwest that frequently visits flowers and attracts attention because of its size and color.  The female lives for 1-2 months seeking out katydids and crickets to provision nests for its young.

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