Beachcombers beware: Storm brings aggressive mantis shrimp ashore on Delaware beaches

Out beachcombing or taking a look at conditions after the storm? Keep your distance from mantis shrimp — and make sure your pets do, too.

Both Dewey Beach and Delaware Seashore State Park reported mantis shrimp on their beaches Wednesday, and they're likely to wash up on many of Delmarva's beaches after a storm. Also known as "thumb splitters," the aggressive crustaceans can easily injure a human or pet.

Though you never know what kind of marine life you'll find on the beach, the mantis shrimp species most seen on Delmarva (according to iNaturalist) is squilla empusa, the west Atlantic mantis shrimp. This species has "a pair of long, jackknife claws that resemble a praying mantis," which they use "to spear or slice through prey with a quick, slashing motion," according to the Chesapeake Bay Program.

"The strike velocity of a mantis shrimp’s large, powerful claws is one of the fastest movements of any animal on earth," the Chesapeake Bay Program's profile on the species says. "It takes a mantis shrimp less than 8 milliseconds to strike, which is about 50 times faster than the blink of a human eye."

Adult western Atlantic mantis shrimp grow to be about 8 to 10 inches long, according to the University of Michigan Museum of Zoology. They can be found from Cape Cod to the Gulf of Mexico, as well as along the coast of Brazil and in the Mediterranean Sea, and favor muddy intertidal zones.

More:Hurricane Ian remnants continue to hit Delaware beaches, but replenishment is on the way

Shannon Marvel McNaught reports on Sussex County, Delaware, and beyond. Reach her at smcnaught@gannett.com and on Twitter @marvelmcnaught