Pacific Cicada Killers Identification Guide
Sphecius convallis
Large solitary wasps native to the Pacific coast that dig burrows in sandy soil and hunt cicadas. Despite their intimidating size, Pacific cicada killers are docile and rarely sting.
Taxonomy
Pacific Cicada Killers Coloration
Common color patterns to help identify pacific cicada killers
Pacific Cicada Killers
Seasonal Activity
When pacific cicada killers are most active throughout the year
Where Pacific Cicada Killers Are Found
Hover over states to see their names. Green regions indicate where pacific cicada killers have been reported.
Pacific Cicada Killer Identification Guide
Physical Characteristics
Pacific cicada killers are large wasps that grow 1 to 1.75 inches long. Their size often startles people, but these wasps are gentle and rarely sting. The head and thorax are reddish-brown to tan. The abdomen has black and pale yellow bands. The yellow color often looks lighter or more cream-colored than on eastern species. Wings are amber to light brown.
Females are larger than males and have a stinger. Males have a fake stinger that cannot pierce skin. Both have six yellowish legs and large eyes that help them spot cicadas in trees.
Pacific cicada killers have lighter colors than the Eastern cicada killer (Sphecius speciosus). This helps them blend with the sandy soils and dry areas where they live.
Regional Distribution
Pacific cicada killers live along the western coast of North America. They range from southern British Columbia through California. They also live inland in Nevada, Arizona, Utah, and Idaho. In Mexico, they are found in Baja California and Sonora.
This species plays the same role as the Eastern cicada killer. They are adapted to the cicada species and climate of the Pacific region. They emerge and become active when local cicadas are present.
Pacific Cicada Killer Behavior and Biology
Pacific cicada killers are solitary wasps. Each female builds and stocks her own nest. They do not form colonies or share resources. When soil conditions are good, many females may nest close together. This can look like a colony, but each wasp works alone.
Hunting Strategy
Female Pacific cicada killers hunt cicadas to feed their young. They use their sharp eyesight to find cicadas on tree branches and trunks. The wasp approaches from below and strikes fast. She grabs the cicada and stings it.
The sting does not kill the cicada. It only stops it from moving. This keeps the prey fresh for the larva. A paralyzed cicada can stay alive for over a week underground. Females hunt whatever cicada species are most common in their area.
Nesting Behavior
Female Pacific cicada killers dig burrows in sandy soil that drains well. They like sunny spots with thin grass or bare soil. Common nesting sites include lawns, garden beds, sandy banks, and bare soil near paths or driveways.
Each burrow goes 6 to 10 inches deep. The female digs with her jaws and back legs. She pushes soil to the surface, making a small mound at the entrance. Inside, she makes one or more chambers. She fills each chamber with one to three paralyzed cicadas. Then she lays one egg on the last cicada in each chamber.
Life Cycle
Pacific cicada killers have one generation per year. Eggs hatch in two to three days. The larva eats the paralyzed cicadas for one to two weeks. It eats everything except the outer shell. Then the larva spins a cocoon and goes dormant through fall, winter, and spring.
The larva becomes an adult in late spring. Adults come out in early summer, usually June or July. This timing matches when cicadas are active. Males emerge first and claim territories near nesting areas. Females come out soon after and mate. After mating, females spend their remaining 60 to 75 days hunting cicadas and filling nests.
Male Territorial Behavior
Male Pacific cicada killers act territorial, which can seem scary. They patrol nesting areas and fly toward anything that enters their space. This includes people, pets, and other insects. A male may hover near your face or dive at you over and over.
This behavior looks aggressive but is harmless. Males cannot sting. They have no way to hurt people. They are just checking out possible rivals or threats. Stay calm and move slowly through the area. The male will lose interest.
Treatment Options for Pacific Cicada Killers
Pacific cicada killers pose little risk to people. They are solitary and not aggressive like yellowjackets. Still, when they nest in busy areas of a yard, treatment may be needed.
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Habitat Changes: The best long-term fix is to make the area less attractive for nesting. These wasps prefer bare or thin soil. Overseeding thin lawn areas in fall creates thick grass that females avoid. Adding 2 to 3 inches of mulch to bare garden soil also helps. Keeping the soil moist can deter females since they prefer dry conditions.
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Physical Methods: Running sprinklers over nesting areas during the day may push females to move elsewhere. This can reduce activity while other methods take effect.
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Targeted Treatment: For ongoing problems, treatment products can go directly into burrow entrances. Evening is the best time to treat when females have returned for the night. Dusts and granular products work well for wasps that nest in the ground.
When nesting happens away from busy areas, many homeowners choose to leave these wasps alone. They pose little stinging risk. But for yards with children or pets, or when burrows create tripping hazards, treatment may be the best choice.
References
Other Wasps
Explore other species in the wasps family
Commonly Confused With
Pacific Cicada Killers are often mistaken for these similar pests
Where Pacific Cicada Killers Are Found
Hover over states to see their names. Green regions indicate where pacific cicada killers have been reported.
Common Questions about Pacific Cicada Killers
Are Pacific cicada killers dangerous?
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Pacific cicada killers are not dangerous to humans. Despite their large size, they are solitary wasps with a docile temperament. Males cannot sting at all. Females have stingers but rarely use them unless directly handled or stepped on. They show no interest in people and are not protective of their burrows like social wasps.
Where do Pacific cicada killers live?
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Pacific cicada killers are found along the western coast of North America, from British Columbia through California, and inland to Nevada, Arizona, and Utah. They prefer areas with sandy or loose soil for burrowing, including lawns, gardens, golf courses, and sandy riverbanks.
How do I identify a Pacific cicada killer?
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Pacific cicada killers are large wasps, typically 1 to 1.75 inches long. They have a reddish-brown head and thorax with black and pale yellow bands on the abdomen. Their wings are amber-colored. Compared to their eastern relatives, Pacific cicada killers tend to be slightly smaller with lighter, more tan coloration.
What do Pacific cicada killers eat?
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Adult Pacific cicada killers feed on flower nectar and plant sap. They hunt cicadas to provision their nests. Females paralyze cicadas with their sting and carry them to underground burrows where their larvae feed on the still-living prey.
Why are Pacific cicada killers digging in my yard?
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Female Pacific cicada killers dig burrows in sandy, well-drained soil to create nests for their offspring. They prefer sunny areas with sparse vegetation. If your yard has these conditions, it may attract nesting females during summer months.
How do I get rid of Pacific cicada killers?
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The most effective long-term approach is to modify the habitat. Thickening lawn grass through overseeding and proper irrigation discourages nesting. Applying mulch to bare soil areas also helps. For immediate concerns, treatment products can be applied to individual burrow entrances.
When are Pacific cicada killers active?
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Pacific cicada killers emerge in early to mid-summer and remain active through late August or September. Their activity coincides with cicada populations in the region. Adults live for about 60 to 75 days.
Do Pacific cicada killers damage lawns?
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Pacific cicada killers cause minor lawn damage. Each female digs one or more burrows, creating small mounds of excavated soil. While this can be unsightly in manicured lawns, the tunneling actually aerates the soil. The damage is cosmetic and does not harm plant roots.
With five years of hands-on experience in the pest control industry, George Schulz is a registered technician with the Virginia Pest Management Association and a proud third-generation professional in a family business that's been protecting homes for over 57 years. He manages and trains a team of service pros while also leading internal research efforts—recently spearheading a deep-dive review of thousands of documents on pest control materials to hand-pick the most kid and pet friendly, most effective solutions tailored specifically for homes in the DC metro area.