Arizona bark scorpion season: Where they hide and what happens if you get stung

As the desert heats up, scorpions — including the notorious Arizona bark scorpions — become more active, leading to more frequent sightings not only outdoors but in homes and other buildings.

These venomous arachnids are adept climbers and can be found in various habitats, including desert scrubland, urban areas and suburban neighborhoods. While bark scorpions are not typically aggressive, their sting can cause painful symptoms, especially in vulnerable populations such as young children or older adults.

Here is everything you need to know about the Arizona bark scorpion, including how many people have died from being stung.

And if you're curious about other common Arizona creatures, check out our guides to black widow spiders, cicadas and palo verde beetles.

What is the difference between scorpions and Arizona bark scorpions?

We talked to Richard Hofstetter, professor of forest entomology at Northern Arizona University, who explained how to tell a bark scorpion from other scorpion species:

  • Size: Bark scorpions are relatively small compared to other scorpion species, typically measuring 1-3 inches in length. “Some can be quite large, up to three inches," Hofstetter said. "But I would say a lot of them, we tend to see the young ones and they can be quite small, just an inch or two.”

  • Color: “One of the ways to tell, and there are a lot of scorpions obviously in Arizona, but the bark scorpion tends to be on the smaller side and kind of a tan color,” Hofstetter said. Their coloration helps them blend in with their surroundings, especially on tree bark or rocky surfaces.

  • Pincers: Bark scorpions have slender, elongated pincers that are typically lighter in color than their bodies. The pincers are used for grasping prey and defending against predators. “The pincers and stinger are fairly thin and the legs are thin. So that's also a good way to tell them from some other scorpions,” Hofstetter said.

  • Tail segment: An Arizona bark scorpion's tail segment is thin and elongated, with a slender stinger at the tip. The stinger contains venom used to subdue prey and defend against threats.

  • Behavior: Bark scorpions are nocturnal and seek shelter during the day in dark, protected areas such as under rocks, logs or debris. They are agile climbers and may be found on walls, ceilings or in trees.

How common is the Arizona bark scorpion?

The Arizona bark scorpion is common in the Southwestern United States, particularly in Arizona, as its name suggests. It is one of the most frequently encountered scorpion species in the region.

It is well adapted to arid environments and can be found in a variety of habitats, including desert scrubland, rocky outcrops, urban areas and even inside homes.

What states have bark scorpions?

States where bark scorpions are commonly found include:

  • Arizona.

  • California.

  • New Mexico.

  • Nevada.

  • Texas.

  • Utah.

What time of year are bark scorpions most active?

Bark scorpions are most active from spring through fall. As nocturnal creatures, they are more active at night when temperatures are milder. During the hottest months of summer, bark scorpions may be active in the early evening and late at night, Hofstetter said.

However, they can remain active year-round in regions with mild winter climates, especially indoors where temperatures are more stable. Hofstetter said it's important to be vigilant for bark scorpions throughout the year.

Are bark scorpions aggressive?

Arizona bark scorpions are generally not aggressive toward humans and typically avoid confrontation. However, bark scorpions will sting defensively if they feel threatened or are inadvertently disturbed.

“If you find them they're not going to chase you. I wouldn’t encourage anyone to try to grab it or use a broom or something to sweep it away,” said Hofstetter.

Are Arizona bark scorpions poisonous?

Yes. Bark scorpions, particularly Arizona bark scorpions, possess venom that can cause swelling and extreme pain.

Fatalities from bark scorpion stings are rare but they can occur, particularly in young children, elderly people and individuals with compromised immune systems.

What happens if you get stung by an Arizona bark scorpion?

The severity of symptoms resulting from a bark scorpion sting can vary widely depending on the individual's age, health and sensitivity to the venom, as well as the location and depth of the sting.

Common symptoms of a bark scorpion sting may include intense pain, swelling, redness and warmth at the sting site. Some people may experience numbness, tingling, muscle spasms, nausea, difficulty breathing and an elevated heart rate, according to the University of Arizona Health Sciences.

Even if symptoms seem mild initially, it's wise to have a health-care professional assess the situation, especially for vulnerable individuals. Treatment may include measures to alleviate pain and swelling, as well as administration of antivenom if necessary.

How painful is an Arizona bark scorpion sting?

The pain from an Arizona bark scorpion sting is often described as intense and immediate.

“They are the most venomous scorpion in North America. So, very painful and the venom can last up to two days," Hofstetter said. "It’s worse than a bee sting and people compared to like an electric shock or something like that. You can be disoriented or you can get numb in the area that's been stung.”

The pain usually begins to subside within a few hours to a day. People may experience prolonged or more severe symptoms if they are particularly sensitive to the venom or if the sting occurs in a sensitive area of the body, such as the hands or feet.

How many people have died from the bark scorpion in Arizona?

Most people who are stung by Arizona bark scorpions in the United States recover fully.

“A couple people die a year but thousands get stung so it’s a very low percentage of people die and it's usually because they have a reaction to it or the sting had occurred in a very bad place like a mouth or something like that,” said Hofstetter.

What attracts bark scorpions?

Bark scorpions are drawn to shelter, moisture and food sources. They seek refuge in dark, secluded areas during the day, such as under rocks, logs or in cracks and crevices. Bark scorpions are attracted to areas with higher humidity levels, such as near water sources or moist areas around homes.

“They're really attracted to kind of moist areas, places where there is humidity and also irrigated lawns. A lot of it has to do with where they prey,” said Hofstetter.

Bark scorpions prey on insects, spiders and other small arthropods, so areas with abundant insect activity, such as gardens or well-lit outdoor spaces, may attract them. Bark scorpions also seek out warm areas during the day to regulate their body temperature.

To deter bark scorpions from your property, eliminate hiding spots, seal entry points, address moisture issues and reduce insect populations. Maintaining outdoor areas free of clutter can further discourage bark scorpions from taking up residence.

Should I be worried if I find a scorpion in my house?

“I would be worried if you find a scorpion in the house," Hofstetter said. "Think about where it's hiding. Maybe you need to make sure it won’t hide there again. You know, they can have up to 40 children, so they can spread very rapidly,” said Hofstetter.

“Oftentimes people get stung or pinched because (scorpions are) underneath things and people don't see them. You know, underneath an appliance or a towel in the bathroom or something like that where they are just trying to hide and wait to come out at night. You can use a blacklight at night to see them really well,” said Hofstetter.

Shake out towels, clothing and shoes before using them, especially if they have been left on the floor, to dislodge any hiding scorpions or other pests.

Take preventive measures such as sealing entry points, eliminating hiding spots and addressing moisture issues. Regularly check for scorpions, as persistent sightings may indicate a larger pest control problem requiring professional help.

Do scorpions climb into beds?

While it's rare for scorpions to climb into beds, it is possible. Scorpions are agile climbers and can scale vertical surfaces, including walls, furniture and bedding, particularly if they are seeking shelter or attracted to warmth.

“They tend to be lower down, maybe a meter or lower, but they are capable of climbing and getting up high, to an attic, for instance,” said Hofstetter.

Are bark scorpions poisonous to dogs?

Bark scorpions can be poisonous to dogs. Symptoms of a bark scorpion sting in dogs may include localized pain, swelling, drooling, lethargy, vomiting, difficulty breathing and, in severe cases, paralysis, according to the Phoenix Veterinary Center.

Reduce your dog's exposure to scorpions by keeping your yard clear of debris and sealing entry points to your home.

What happens if my dog eats a scorpion?

If your dog eats a scorpion, monitor it closely for signs of distress, such as mouth pain, drooling, vomiting and diarrhea. In severe cases, your dog may exhibit weakness, difficulty breathing or paralysis, according to Wag!, a website that connects dog owners with pet care services.

Arizona bark scorpion dog treatment: Can you give a dog Benadryl?

Contact your your veterinarian if you observe concerning symptoms. Treatment may involve inducing vomiting to remove the scorpion from your dog's system, other measures to alleviate symptoms or antivenom.

If you can't reach a veterinarian immediately, there are steps you can take at home, according to the East Valley Animal Hospital:

  • Keep your pet still to prevent spreading the venom.

  • If you can find the sting site, carefully remove the stinger with tweezers.

  • Wash the area with cool water and apply a cool compress to reduce swelling and pain.

  • You can give a dog Benadryl for minor allergic reactions. According to the Merck Veterinary Manual, the standard Benadryl dose is 0.9-1.8 milligrams per pound of body weight.

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This article originally appeared on Arizona Republic: Bark scorpions: What states have them and are they fatal?