Non-native lionfish could endanger marine ecosystems in the US

Non-native lionfish could endanger marine ecosystems in Lee County
Species seen in Keys may invade local waters

Kevin Lollar www.news-press.com 12 Jan 09;

A beautiful and venomous non-native fish has made its way to the Keys, and the question is whether the species will move north and invade local artificial reefs.

The red lionfish, a native of the western and South Pacific, has become the dominant species on many reefs in the Bahamas and Caribbean; in the United States, it has been documented off New York, New Jersey, North and South Carolina, Georgia and the east coast of Florida.

On Tuesday, a diver saw a juvenile lionfish on the Benwood wreck off Key Largo — it was the first documented case of lionfish in the Keys; the following day, a team from the Reef Environmental Education Foundation captured and euthanized the fish.

“It has spread to the east of Florida, Cuba, the U.S. Virgin Islands, the Caymans, so it was inevitable that it would reach the Keys,” said Brian Keller, science coordinator at the Florida Keys National Marine Sanctuary. “These are voracious predators that eat a lot of fish. They compete with snapper and grouper and eat the young of those species.”

Experts say lionfish might have been introduced to the Western Hemisphere as larvae in ballast water and by people who released them from aquariums.

The lionfish’s appetite is not the only concern, said Aaron Adams, head of Mote Marine Laboratory’s Charlotte Harbor Field Station.

“If they don’t have any natural predators, there’s nothing to control their abundance, so their numbers grow, and it will become an issue of competing with natives for food and space,” he said. “I have colleagues working in the Bahamas who have seen grouper eat them and spit them out, sharks as well: They eat them and spit them out.”

A single lionfish doesn’t mean the species will become established in the Keys, but, if it does, the next question is whether it will expand to Lee County.

Although lionfish are a tropical species, they seem to tolerate a wide range of temperatures.

They can’t tolerate water below 50 degrees, Keller said, but Lee County’s water temperatures rarely drop below 60 degrees.

“I’d hoped winter temperatures would keep them away,” said Chris Koepfer, a Lee County natural resources supervisor. “If they can handle down to 50 degrees, we have no hope.

“Lionfish are like any other invasive exotic species: They don’t belong. Like Brazilian pepper, melaleuca and Australian pines, they can take over an entire ecosystem.”

Given the species’ ability to dominate an ecosystem, a lionfish invasion could mean trouble for the county’s 20 artificial reef sites, which are home to more than 150 fish species.

One hope, Koepfer said, is the area’s large population of goliath grouper.

“Maybe goliath grouper will see it as a good food source,” Koepfer said. “Goliath grouper eat burrfish and other slow-moving fish that are tough to eat.

“If goliath grouper don’t eat them, and they can withstand winter temperatures, I wouldn’t be surprised if they become established here.”