Pest profile

Jerusalem Crickets

Stenopelmatidae; e.g., Ammopelmatus fuscus (formerly Stenopelmatus fuscus) · Orthoptera: Stenopelmatidae[3]

Jerusalem crickets are among the largest insects in western North America. Their bald, humanlike head and big jaws alarm people, but they are essentially harmless and rarely pests.[2][1]

Jerusalem cricket with a large, smooth orange-brown head and a fat abdomen banded black and cream, on dry soil
Jerusalem cricket with a large, smooth orange-brown head and a fat abdomen banded black and cream, on dry soil. (c) Sean Vanderluit, some rights reserved (CC BY) — via iNaturalist, CC BY 4.0

How to identify it

  • Look for a bald, round, humanlike head, a fat orangish or shiny brown abdomen with dark bands, long brownish antennae and spiny hind legs.[1][2]
  • Adults and young are wingless and crawl slowly; nymphs look like small adults.[2][1]
  • Adults range from about 1 to 2 1/2 inches long.[2][1]

Look-alikes

Look-alikeHow to tell them apart
Pillbugs and sowbugsThey share the confusing nickname potato bug; none of these is a true bug, so check for the Jerusalem cricket's bald, round head and banded abdomen.[1]
Colorado potato beetleAlso called potato bug; the Jerusalem cricket is instead a large, wingless cricket that lives mostly underground.[1]

Where it lives

In North America they are found only west of the Rocky Mountains; the most widespread species in California is Ammopelmatus fuscus, the species this profile centers on.[2]

Biology and life cycle

They feed and tunnel underground by day and come aboveground mostly at night or twilight, often after heavy rain or irrigation.[1][2]

In summer they hide under rocks, logs and boards during the day.[2]

They eat insects, nonwoody roots and tubers, and sometimes dead animal matter.[1][2]

Eggs are laid in soil; nymphs molt up to about 10 times and can live up to about 2 years.[1]

They make sound by rubbing a hind leg against the abdomen, and females sometimes kill males after mating.[2]

Damage and signs

  • They only occasionally feed on potato tubers, turf or vegetables and aren't considered agricultural or garden pests.[1][2]

Health risk

They are harmless to people, but their strong jaws can bite, so handle them with care.[1][2]

Control

Traps and physical control

No control is necessary; if one is somewhere unwanted, scoop it into a box and move it.[1]

Biological control

Leave them be where possible: they are important food for barn and burrowing owls, kestrels and other predators.[2][1]

Common questions

Are Jerusalem crickets poisonous?
No. Much of their scary reputation is myth; they can bite if handled, but they are essentially harmless.[2][1]
Why are they called potato bugs?
They occasionally feed on potato tubers, though the same nickname is used for several unrelated creatures.[2][1]

Sources

  1. University of California Statewide IPM Program, “Jerusalem Cricket (Pest Notes, Home and Landscape).” ipm.ucanr.edu/home-and-landscape/jerusalem-cricket/ (accessed 2026-10-06)
  2. Bohart Museum of Entomology, University of California, Davis, “Information Sheet No. 008: Jerusalem Crickets.” bohart.ucdavis.edu/sites/g/files/dgvnsk4616/files/media/documents/note_08_jerusalem_cricket.pdf (accessed 2026-10-06)
  3. iNaturalist, “Ammopelmatus fuscus taxon page (order and family).” www.inaturalist.org/taxa/1193580 (accessed 2026-10-06)

Updated 2026-10-06. Built from sourced records. Spot an error? Tell us.