Steel-Blue Cricket Hunters Identification Guide

Steel-Blue Cricket Hunter Identification Guide

Physical Characteristics

The steel-blue cricket hunter is a large thread-waisted wasp. Adults are about 3/4 inch to just over 1 inch long. The size and bright color make people stop and stare.

Key features include:

• Color: The whole body is metallic steel blue. In bright sun it can flash blue-green or violet. The legs and antennae are black.
• Wings: Smoky dark brown, often with a faint purple or amber tint toward the tips.
• Shape: A narrow waist joins the thorax to a shiny, rounded abdomen. The legs are long and spiny.
• Behavior you can see: It runs over the ground in quick bursts, flicking its wings and tapping its antennae as it hunts.

How to Tell It Apart From Look-Alikes

Several blue or black wasps share the same yards in summer:

• Blue mud daubers (Chalybion californicum) have a very similar color. They are usually smaller and have a longer, thinner waist. They hunt spiders, not crickets, and are most often seen near mud nests on porches, sheds, and attics.
• Great black wasps (Sphex pensylvanicus) are larger, up to 1.4 inches. Their body is mostly flat black, with the blue shine showing mainly on the wings. They hunt katydids and are common on flowers.
• Spider wasps (family Pompilidae), including blue-black spider wasps (Anoplius), also flick their wings nervously. They lack the stalk-like waist and drag spiders rather than crickets.
• Cicada killers are much bigger and have rusty red and yellow bands. They are not blue, but cricket hunters often nest right in their burrows, so you may see both at once.
• Blue-winged wasps are hairy and black with two yellow spots and an orange tail end. They hover low over lawns hunting grubs.

Common Species

Chlorion aerarium is the most widespread member of its genus in the United States and Canada. A few relatives occur mainly in the Southwest and Mexico. Its closest everyday relatives are the great golden digger wasp and other digger wasps.

Steel-Blue Cricket Hunter Behavior and Biology

Habitat

These wasps prefer sunny, open ground with loose or dry soil. Common spots include lawn edges, garden beds, sandy paths, ball fields, and bare patches under shrubs. Public sighting records show them in nearly all of the lower 48 states, southern Canada, and northern Mexico. They are common in Maryland, Virginia, and DC.

Adults rarely feed at flowers. They more often drink sap oozing from wounded plants, though they will visit nectar sources like bee balm.

Diet and Hunting

As the name suggests, females hunt field crickets. In the eastern U.S., the main prey is the fall field cricket, Gryllus pennsylvanicus. A female searches leaf litter and garden debris. She flushes a cricket from hiding and stings it several times. The venom paralyzes the cricket but does not kill it.

She then grabs the cricket by its antennae and drags it back to her burrow. University of Maryland entomologist Michael Raupp has written about watching this behavior in his own yard and garden.

Nesting and Life Cycle

The steel-blue cricket hunter has an unusual nesting habit. It often uses the burrow of a cicada killer as a front hallway. The female digs small side tunnels off the main shaft. She builds several cells in them. Where cicada killers are scarce, she may start her own burrow or borrow one left by another wasp or bee.

Each cell gets between two and nine paralyzed crickets. She lays one egg on a cricket, then seals the cell with soil, small stones, and debris. The larva hatches and eats the stored crickets. Then it spins a cocoon and spends the winter underground. New adults come out the next summer.

There is one generation per year. In the Mid-Atlantic, nest building peaks in late July and August.

Sting Risk

Steel-blue cricket hunters are solitary. Each female works alone. There is no colony to defend, so they seldom sting people. Females sting only when they are handled, trapped against skin, or stepped on. Males have no stinger.

A sting is painful but brief for most people. People with a known allergy to wasp or bee stings face a greater risk from any stinging insect. This is not medical advice. If you are stung and have trouble breathing, swelling of the face or throat, or dizziness, get emergency care right away and talk to your doctor about an allergy plan.

How Pest Control Companies Treat Steel-Blue Cricket Hunters

Homeowners usually call when burrows sit in busy spots, like a sandbox, a patio edge, or a walkway. Cricket hunters often share burrows with cicada killers. For that reason, a typical service covers the whole nesting site.

• Inspection: A technician confirms the wasp species and finds the active burrow openings. It is important to rule out yellowjackets. Ground-nesting yellowjackets are far more defensive and need a different approach. As with any stinging insect, if the nest can’t be found, it can’t be treated.
• Treatment: For ground-nesting solitary wasps, the usual method is an EPA-registered insecticide dust or residual product put right into each burrow opening. This targets the wasp where it nests instead of spraying the whole yard. The product label controls how and where it can be used, and some labels limit use far from a building.
• Prevention & customer guidance: These wasps favor dry, bare, sunny soil. Thick turf, mulch or landscape fabric over bare beds, and regular watering make an area less attractive. Lowering field cricket numbers around the home also removes their food. Our pest control service targets crickets and other perimeter pests, and our team can look at ground-nesting wasps during a visit.

If you are in Northern Virginia, DC, or nearby Maryland and are not sure what is digging in your yard, our technicians can identify it and walk you through your options.

References

• Crickets beware: Steel-blue cricket hunter, Chlorion aerarium, Bug of the Week, Dr. Michael J. Raupp, University of Maryland
• Chlorion, Sphecid Wasps of Michigan, University of Michigan Museum of Zoology
• Species Chlorion aerarium, BugGuide, Iowa State University
• Warning to Cicadas: Watch Out, Penn State Extension
• Cicada Killer Wasps (E-254), Purdue University Extension Entomology
• Insects and Scorpions at Work, CDC / NIOSH