Bugs and spiders in Nevada

What to watch for in Nevada

The western black widow is the first to watch, and an adult female's bite can cause severe muscle pain and cramps, so get medical advice right away. The Arizona bark scorpion is established in the southern low-desert areas of the state. Its sting is very painful and can be dangerous for young children and older adults; call Poison Help at 1-800-222-1222 right away.

Two ticks are established: the Rocky Mountain wood tick, with few records, and the brown dog tick, which feeds mostly on dogs and can breed indoors. Both can carry disease. Records exist for the American dog tick and the brown widow, but sightings like these are often misidentifications or hitchhikers rather than local populations.

Through the year

Spring

Rocky Mountain wood ticks are active from snowmelt, zebra jumping spiders appear in spring, and pill bugs turn up indoors after long rainy periods.

Summer

Bark scorpions are active on warm nights above about 70°F, western black widows are most active through fall, and European paper wasps work around the outside of the house.

Fall

Western conifer seed bugs move in during September and October, Asian lady beetles in October and November, and European earwigs are seen most in late summer and fall.

Winter

Bark scorpions are least active from November through March, firebrats gather near furnaces and heating pipes, and Argentine ants may turn up indoors after heavy rain or hot, dry spells.