Scorpions in Arizona Homes: What New Residents Should Know

Yes, you will likely see scorpions in Phoenix-area homes, and the one that matters is the Arizona bark scorpion. It is small, light brown, climbs walls, and comes out at night in warm weather. Sealing gaps, clearing clutter near the house and checking with a blacklight keep most homes in good shape.

When I help people move here from out of state, scorpions come up in almost every first conversation. Usually it is right after the heat question. I get it. If you have never lived in the desert, the idea of finding one on your bathroom floor sounds like a deal breaker. The good news is that most Arizona homeowners learn to live with them the same way people in other states deal with ants or mice: a few habits, a little prevention, and knowing what to do if something goes wrong.

Here is what I tell my clients, based on guidance from the University of Arizona and the Banner Poison and Drug Information Center.

Meet the Arizona bark scorpion

Arizona is home to about 30 kinds of scorpions, but according to University of Arizona Cooperative Extension, only one is considered life-threatening: the bark scorpion. University of Arizona Health Sciences goes a step further and notes it is the only scorpion in North America that is dangerous to people.

It is easy to recognize once you know what to look for. Bark scorpions are about two inches long and light brown. Unlike many other species, they do not dig burrows. They climb. That is why people find them on walls and ceilings instead of under the ground.

When and where they show up

Scorpions hide during the day and hunt at night. UA Extension says they are active when overnight lows stay above roughly 77 degrees, which is why you hear about them most during our long summers. Banner's poison center reminds residents each spring that sightings pick up as temperatures climb. Homes near washes and arroyos can see more of them during monsoon storms, when moving water pushes them around.

Around a home, they like protected spots:

• Wood piles, sheds, loose boards and rock piles
• Gaps under doors with worn door sweeps, and torn window screens
• Firewood carried indoors
• Shoes, towels and clothes left on the floor
• Dark, quiet areas like garages and closets

They also follow their food. If a house has crickets or cockroaches, scorpions have a reason to come inside.

How to keep them out of your house

University of Arizona Extension makes a point I repeat to buyers: you cannot manage scorpions with pesticides alone. Changing the habitat around your home does most of the work. Here is the short list:

• Seal it up. Caulk cracks and gaps, and replace worn door sweeps and weatherstripping.
• Clear the edges of the house. Move woodpiles, rocks, boards and clutter away from walls, and trim shrubs and branches so they do not touch the structure.
• Bring in only the firewood you need for that day.
• Cut down on the bugs they eat. Fewer crickets and roaches means fewer scorpions.
• Wear shoes at night, inside and outside, and use leather gloves when moving things in the yard.
• Shake out shoes and clothes before putting them on.

For bedrooms, UA Health Sciences suggests keeping bedding and curtains from touching the floor and placing the legs of a crib or bed in glass jars, since bark scorpions cannot climb glass. Parents of little ones tend to love that tip.

The blacklight trick

Scorpions glow under ultraviolet light. With a portable UV flashlight, you can spot one from several yards away on a warm night. Plenty of homeowners do a quick sweep of the yard, patio and garage after dark to see what they are dealing with. UA Extension also offers one safety note: never look straight into a UV light, because it can hurt your eyes.

If someone gets stung

I am a REALTOR®, not a medical professional, so here is what the experts say. Banner's poison center advises staying calm, washing the area with soap and water and using a cool compress. Then call Poison Control at 1-800-222-1222. It is free and answered 24 hours a day. Most stings cause pain, tingling or numbness that starts to ease within a few hours, and most people are able to be cared for at home with the center's guidance.

Young children and older adults are at higher risk of serious symptoms, so call right away for them. Get medical help immediately for trouble breathing, chest pain, muscle spasms, or severe swelling. UA Health Sciences also warns that a sting is not an allergic reaction, so antihistamines and EpiPens are not the treatment and can make symptoms worse. Antivenom is available at Arizona hospitals for severe cases.

Should scorpions change which home you buy?

In my experience, scorpions are part of living in the Sonoran Desert, not a reason to avoid a neighborhood. Homes next to washes or with a lot of yard clutter may see more activity, but prevention works almost anywhere. During the inspection period, it is fair to ask the sellers about pest control history and have your home inspector note gaps around doors and windows. I walk through that process in Getting Through the Arizona Inspection Period.

If you are still in the planning stage, my Moving to Phoenix guide and Phoenix cost of living page cover the bigger picture, and you can compare areas on the Arizona cities guide.

Questions people ask

Are there scorpions in every Phoenix-area home?
No, but they can show up in almost any part of the Valley. Homes near washes, and homes with clutter or gaps around doors, tend to see more.

What time of year are scorpions most active in Arizona?
They are most active in the warm months, especially summer, and sightings start picking up in spring. UA Extension says they come out when nighttime lows stay above about 77 degrees.

Can a bark scorpion climb walls?
Yes. Bark scorpions are climbers, which is why they turn up on walls and ceilings. They cannot climb smooth glass.

Who do I call if I get stung?
Call Poison Control at 1-800-222-1222, which is free and open 24 hours a day. Go for emergency care right away if there is trouble breathing, chest pain or muscle spasms.