Scientists have confirmed that red lionfish have invaded the Gray’s Reef National Marine Sanctuary, 20 miles off the Georgia coast.

A marine biologist photographed two of the adult lionfish in the sanctuary in late September during a scientific dive. The pair was spotted roughly 70 feet below the sea surface, providing insight into just how close to shore the fish can survive when the area’s water temperature cools in the winter.

The venomous fish threatens divers with excruciatingly painful stings that spread to the entire limb and regional lymph nodes, with discomfort lasting up to 12 hours. Even more troubling is the fact that such an injury hasn’t been encountered previously by local physicians and hospitals.

Native to the western Pacific Ocean, red lionfish are a favorite of the saltwater aquarium trade and were likely introduced into the southeast Atlantic coast during the early 1990s. Recently, the invasive species was found in shallower waters from Florida to North Carolina at various temperatures, raising concerns that the fish might spread farther and faster than originally thought.

"Discovery of the lionfish represents a challenge for both sanctuary management and scuba divers in the area,” said George Sedberry, Gray’s Reef sanctuary superintendent. “Without any natural predators in southeastern waters, lionfish put indigenous marine species at risk due to competition for food and space and their role as a predator of smaller fish."