A San Rafael man building a play structure for his children had an unpleasant surprise this week when he discovered two scorpions in his backyard.

Gerstle Park resident Valon Grajqevci said he pulled up a rock while leveling his yard Monday afternoon and found two gray-black scorpions measuring between two and three inches.

“I was like, ‘Oh my God, Scorpion King is in my backyard,'” Grajqevci said.

Grajqevci said his wife was originally skeptical, suggesting the creatures might instead be crickets. But she told him to get their 2- and 4-year-old daughters inside after he texted her a photograph that clearly showed the scorpions’ tails and pinchers.

After corralling the scorpions in a plastic container with breathing holes, Grajqevci contacted the California Academy of Sciences.

The academy suggested he release them in the woods, Grajqevci said. However, he later decided to drop the critters off at WildCare in San Rafael on Tuesday.

“If I didn’t have kids, I probably wouldn’t have done anything,” Grajqevci said, noting that his daughters are too little to identify whether they’ve been stung by a bee or scorpion and he doesn’t know whether they’re allergic.

The type of scorpion Grajqevci found in his yard is known as Uroctonus mordax and is common in Marin, said David Herlocker, an interpretive naturalist for Marin County Parks. They don’t pose much danger, he said.

“It’s found in virtually all habitats, mostly forested habitats, bay woodland, which is super common in Marin,” Herlocker said. “It’s also found in redwood and douglas fir forests.”

The creatures are nocturnal and hunt for insects and spiders after dark, he said, adding, “When we get rains like this, a lot of animals, particularly nocturnal animals, that tend to hide in dark places, they’ll get flooded out.”

Unlike scorpion varieties in northern Mexico and other areas, the Uroctonus mordax has only a mild poison and most stings will require only ice as a remedy, Herlocker said.

“They’re not dangerously poisonous, although it does sting,” Herlocker said. “You almost have to try to get stung by one.”

According to an Alameda County Vector Control Services District report, Uroctonus mordax’s venom is rated 1 in a scale of 1 to 5.

“Scorpion stings from level 1-3 usually aren’t significant in any way, unless however the sting victim is allergic to the scorpion’s venom, then it may cause adverse side effects (shortness of breathing, swelling of the extremity stung, etc.),” the report states.

Residents who find a scorpion outside should either let it be or transport the creature to the nearest natural forest habitat, Herlocker said.

Anyone interested in learning more about other wildlife native to Marin may participate in county parks’ free naturalists programs, he noted.

For information, go to www.marincountyparks.org.

Contact Jessica Bernstein-Wax at jbernstein-wax@marinij.com or via Twitter at http://twitter.com/jbwax.