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Discovery Of Invasive Zebra Mussel Prompts Warning From State Officials

Karen Meisenheimer

Marion Clarke (352)392-1837
Tom Quinn (850) 488-6253

GAINESVILLE — State officials made the first confirmed sighting of thenon-native zebra mussel, a meddlesome mollusk that a University of Florida scientist says can displace native aquatic life and cause billions of dollars of structural damage.

During a routine inspection of a bait-and-tackle shop in Eustis, officials discovered the mussels, believed to have been transported from Lake Champlain in New York. They confiscated and destroyed the mussels and expect no infestation from that source, said Marion Clarke, a professor with UF’s Institute of Food and Agricultural Sciences.

Zebra mussels are thumbnail-size bivalves with black and white stripesthat first arrived in North America in 1986 in the bilge water of Russian freighters. They have wreaked environmental and economic havoc throughoutthe Great Lakes states and have worked their way down the Mississippi River as far as New Orleans, Clarke said.

“The zebra mussels pose an alarming threat because they are very prolific reproducers,” Clarke said, “and they have no natural predators to help control their numbers.”

The mussels are the only freshwater mollusk that attach themselves to solid objects. Once established, zebra mussels clog up intakes pipes, waterlines and pumps, forcing costly cleaning programs, said Clarke, an assistant dean with the Florida Sea Grant Program.

“Zebra mussels will clog up everything,” he said. “They’re found in pipes of power plants, water treatment plants and even in the irrigation systems at golf courses. Industrial operations in the Great Lakes states have spent millions of dollars in clean-up.”

Adult zebra mussels, which can live 10 to 15 days out of water, attach themselves to boat hulls, trailers or outboard motors. During the larval stage, a zebra mussel is free-floating and almost invisible, making it easy for them to be transported from a contaminated source.

“Our biggest concern is that someone will unknowingly trailer them into Florida on a boat from one of the states where the waters are already infested,” Clarke said. “You could even find the mussels in bait buckets,live wells and other type of water-related gear such as fishing poles or snorkeling equipment.”

The zebra mussel also is a threat to native freshwater mussel and clam species and other aquatic animals. They filter out so much algae, Clarkesaid, that they starve native species, interrupt the food chain and stimulate the growth of unwanted plants.

“Residents and visitors need to know that it is absolutely illegal to bring zebra mussels into the state of Florida or to even have them in your possession,” said Tom Quinn, an inspector with the Florida Game and FreshWater Fish Commission. “It is a second-degree misdemeanor that carries a $500 fine and up to 60 days in jail.”

The Florida Sea Grant Program is working on public education programs to create public awareness and ward off an invasion of the pest organism before it reaches the costly level it has elsewhere.

A 1997 Florida Sea Grant-funded research project identified Florida waterways that could be susceptible to a zebra mussel infestation. The BigBend region, the St. Johns River system and water bodies north of Lake Okeechobee all have characteristics that are suitable for zebra mussel inhabitation, Clarke said.

Boaters can take a few simple precautions to prevent the introduction of zebra mussels into Florida’s waters.

“Boaters need to be able to identify the zebra mussel and should be aware of currently infested waters,” Clarke said. “If they’ve launched their boat in infested waters, they should inspect and clean the boat and all their gear before leaving the site.

“It’s necessary to flush the engine cooling system, live wells and bilge with hot water. The boat and trailer should be allowed to dry in the sun for three to four days before being used again.”