Hot, Dry Summer Has Scorpions In Texas Heading Indoors

With rising Texas summer temperatures, humans aren’t the only life forms trying to find a cooler place.

“There have been a lot of calls coming into the office recently from residents of San Antonio and from surrounding counties about scorpions,” said Molly Keck, Texas A&M AgriLife Extension Service entomologist, Bexar County.

Scorpions don’t seem to like either very cold or very hot temperatures, Keck said. And during hot, dry weather, they may seek out water and/or a more hospitable environment. Scorpions can typically be found under rocks, paving stones, logs or landscaping materials — or hiding in wood piles or inside the home.

“We’ve had two or three wetter, more moderate summers in a row, but this year we’re getting more of the weather people tend to expect when they think of summer in southern and central parts of Texas,” Keck said.

Scorpions are nocturnal, hiding during the day and becoming active at night, explained Wizzie Brown, AgriLife Extension Service entomologist, Travis County, who said she is not surprised by the increase in calls relating to scorpions.

“This behavior helps them manage temperature and water balance, which are important functions for survival in dry habitats, Brown said. “Their bodies are flat, which allows them to hide in small cracks and under stones, bark, wood or other objects as they wait or search for prey.”

Scorpions have two pincers, or claws, called pedipalps, which help them hold their prey as they eat, plus a long tail with a stinger on the tip used for defense or to paralyze prey, she said. They also have two eyes on the top of the head and usually two to five pairs of eyes along the head’s front corners.

“They do not see well, however, and must rely on their sense of touch for navigation and detecting prey,” Brown said. “However, scorpions do have a well-developed sense of hearing.”

Texas has 18 species of scorpions, but only the striped bark scorpion occurs throughout the state and is the most common species in Central Texas, she said.

“This scorpion is yellowish-tan with two dark stripes that run along the back,” she said. “Striped bark scorpions can get up to 2½ inches in length.”

Brown said while striped bark scorpions are capable of stinging, the sting typically only causes moderate reactions in most people as their poison has little effect on the nervous system.

“Usually it’s sufficient to apply ice packs on the area where the sting occurred to reduce pain and swelling,” she said. “But the severity of the sting is dependent upon the individual scorpion and the person’s reaction to the venom. A person stung by a scorpion should be watched closely for several hours following the incident to ensure an allergic reaction does not manifest. If breathing becomes difficult or hives occur, seek immediate medical attention.”

When working outside, wear leather gloves to avoid being stung, Brown noted.

Keck and Brown noted the best defense against scorpions is exclusion and offered the following tips for keeping scorpions from getting into a home:

• Keep debris and firewood away from the house.
• Prune any trees or shrubs touching or hanging over the house.
• Keep grass near or touching the house closely mowed.
• Replace weather-stripping around doors and windows as necessary.
• Fill weep holes in stone, brick or stucco homes with steel wool, copper mesh or screen wire.
• Seal cracks, crevices and areas of pipe penetration in exterior walls with sealant.
• Keep window screens in good repair and make sure they fit tightly into the window frame.
• Treat the foundation of the home with a pesticide with ingredients such as permethrin, cypermethrin, deltamethrin, carbaryl or propoxur.

If scorpions are found, the entomologists suggest applying pesticides around the foundation of the house and up to one foot above ground level on the exterior walls. They also suggest applying pesticides around doors, windows, eaves and other potential points of entry. Indoor treatments should be directed at potential points of entry as well as corners, cracks and crevices where scorpions can hide. Follow label directions for dosage, mixing and application methods.