While it has been less than two years since scuba diver Lawren McCaghren made the first confirmed sighting of a lionfish off Alabama, the animals are now so common that McCaghren said he routinely sees 50 or 60 during a single dive on local reefs.
The sudden colonization of the northern Gulf has scientists using words like alarmed, worried and afraid. First noted off the Atlantic Coast in the 1990s, lionfish swept across the Caribbean in three short years.
“The explosive nature of the population expansion is ominous. We’re getting reports of thousands of them documented across the northern Gulf and thousands in the Keys, all within a few years,” said Bob Shipp, head of marine sciences at the University of South Alabama.
“Whether they replace some of our native species on the reefs, or it is a temporary expansion that will level off, we just don’t know. They don’t have any natural predators. Perhaps some of our predators will eat them, but we have no indication of that yet.”
Lionfish, named for a lovely mane of elaborate fins that rings their bodies, are native to the Pacific Ocean. They are not native to the Gulf or Atlantic. The fish grow to about 15 inches long, but appear much larger due to the fan of fins that spread out around the body. The body is striped with bands of brown, rust, and white.
Scientists believe captive lionfish may have escaped from aquariums in south Florida during Hurricane Andrew in 1992. A few were seen off North Carolina around 2000, and reports of sightings began trickling in from the Caribbean around that time.
Within three years, lionfish had colonized the entire Caribbean and are reported to have eaten or displaced about 60 percent of the native species on reefs there. Lionfish have enormous mouths in relation to the size of their bodies, similar to a largemouth bass. They can consume fish nearly as big as they are.
The fish have become so prevalent in the Florida Keys that dive groups hold tournaments to see who can kill the most lionfish in a day. About 1,500 lionfish were killed in derbies in the Keys in 2011, a number scientists say represents a small drop in a huge bucket.
“Anywhere you go in the Gulf, you see them. Tanks and pyramids, they’re a given,” said McCaghren, manager of the Gulf Coast Divers shop in Mobile. McCaghren filmed a lionfish swimming on an Army tank off Alabama in September of 2010, the first northern Gulf sighting. Within a matter of weeks, divers reported encountering the fish on reefs off Florida and Louisiana.
“The natural bottom stuff, the Trysler Grounds, you don’t see one or two. You see 50 or 60 out there every dive. They’re on every outcropping,” McCaghren said, referring to an area of natural coral reef habitat about 20 miles off the Alabama coast.
McCaghren said he has killed about 100 using a small spear known as a “Lion Tamer.” Because each lionfish possesses three sets of venomous fins, he said he usually knocks them off the spear and leaves them in the water rather than trying to bring them back to the dock to eat.
A lionfish killed by the Press-Register on Tuesday yielded two small filets. The meat was firm and white and tasted delicious sauteed in butter. To clean it, the venomous barbs were simply clipped off with a pair of wire snips.
If you get stung by a lionfish, run the wound under hot water and seek medical attention. The telltale water stream from an outboard motor can be used to provide hot water if you get stung while offshore.
While federal officials have been encouraging people to eat lionfish, it appears unlikely that such a program will make a dent in the Gulf population. In part, that’s because the fish don’t typically take a baited hook, and in part it is because they have apparently colonized the deepest parts of the Gulf.
“No one expected to see a lionfish at 1,400 feet down, but that’s what we’re seeing,” said Thomas Jackson, an exotic species biologist with the National Oceanic and Atmospheric Administration.
Jackson said he believes that lionfish are reproducing in the deep recess of the Gulf and moving in toward shore. Because the fish are native to the Pacific, he said, they are likely more tolerant of the colder water far offshore than many native species.
Shipp, with the University of South Alabama, said that might explain why most of the lionfish seen by divers in the Gulf are relatively small.
“These fish get up to 15 inches, but we’re not seeing that size. Most of the reports I’ve heard are juveniles,” Shipp said. “That’s alarming. If they are establishing themselves here as juveniles, without even reproducing locally, well, who knows what will happen if they start reproducing around here.”
A survey of scuba divers with spearfishing permits conducted by the Dauphin Island Sea Lab yielded hundreds of reports of lionfish in area waters. One fish was reported under a pier in Old River next to Ono Island, in just a few feet of water. Last week, a lionfish was killed in 11 feet of water at Fort Pickens in Pensacola Bay.
“I’m hoping this won’t be like the brown tree snake in Guam. You’re talking about an entire ecosystem that has these predators in very large numbers,” Jackson said. “Our systems are already stressed. Now we’re adding a very efficient predator.”
Jackson said that it is still legal to import a number of lionfish species in the United States, including species that have not yet escaped into the wild. “It is not a good idea to continue to allow the sale of these fish,” he said.
“I think it’s only a matter of time until the lionfish move into shallower water and get into our coastal ecosystem,” McCaghren said. “Fishermen don’t understand the threat yet because they don’t see them. They’re here now. And the difference they’ve made in just a few years is incredible.”
Thanks to All Alabama Kathy Dowsett
www.kirkscubagear.com
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