Lawton, Okla. ? Biologists at the Wichita Mountains National Wildlife Refuge have added an unusual species to the list of wildlife living on the refuge – a freshwater jellyfish.

Steve Hodge, a biological technician for the U.S. Fish & Wildlife Service, said he was skeptical when he first heard a report that the jellyfish were discovered by a visitor to one of the lakes at the refuge.

“I was blown away, to be honest with you,” Hodge said. “I’ve been on so many false alarms and all that in my life since I’ve been here, I thought, ‘Yeah, jellyfish. Sure.’ And dang, there it is, right there, jellyfish.”

During a September survey of species by the Oklahoma Biological Survey, participants counted more than 1,000 species within the refuge’s nearly 60,000 acres, but the jellyfish was not one of them.

But Hodge said he observed about eight of the jellyfish floating around a lake on the refuge later that month.

“They’d be in about three feet of water or so, and then they’d circulate and come up close about six inches from the surface and then just kind of fade right down into the bottom again where you couldn’t find or follow them,” Hodge said.

The ones he saw were only about the size of a quarter, and some were a little smaller.

Hodge said biologists have been trying to learn more about the freshwater jellyfish ever since. The species, craspedacusta sowerbii, have been found most often in calm freshwater lakes, reservoirs, manmade impoundments and water-filled pits or quarries.