Florida's ban on importing invasive lionfish, the first of its kind in the nation, goes into effect on Friday as wildlife managers look for a way to control the spread of the barbed, red-and-white striped fish.
Bringing the fish into the state is now punishable by a fine of up to $1,000 and a year in prison.
Lionfish, native to the waters off Southeast Asia, are believed to have arrived in the region as pets for aquariums. Over time, some were released into the wild.
The Florida Fish and Wildlife Conservation Commission, which approved the ban in mid-June, also loosened fishing rules making it easier for recreational divers and fisherman to catch lionfish.
Scientists are concerned that lionfish will decimate other species found in Florida waters. The fish, which have few known predators, live in warm waters up to 1,000 feet deep and feed on anything from shrimp to other fish.
The loinfish, which can grow up to a foot in length, are covered in poisonous spines. While they are not aggressive, they can flare the barbs much like a porcupine if threatened.
"They're here to stay," said Roldan Muñoz, a researcher with the National Oceanic and Atmospheric Administration in North Carolina who studies the lionfish.
"If we can prevent more of them from getting dumped into the water ... as well as making it easier for people to harvest them it's a good start," he said.
The first lionfish sighting was in 1985 off the coast of South Florida, according to Pam Schofield, a fishery researcher for the United State Geological Service (USGS).
In the mid-1990s they began spreading up Florida's east coast and can now be found year-round from the shores of Venezuela to North Carolina.
Lionfish have been spotted on the U.S. East Coast as far north as Rhode Island, but aren't able to survive in the frigid winter waters.
A lionfish database operated by the USGS includes more than 4,000 sightings logged since 1985, though estimates of the total lionfish population aren't available.
In September, the Fish and Wildlife Conservation Commission will consider additional punishment for breeding lionfish.
(Editing by Frank McGurty and Sandra Maler)