These zebra mussels are hanging on a simple rope, with their depth attributable to their ability to attach to each other as well as other native mussels.[/caption]

Although first spotted in Texas lakes in 2009, zebra mussels were discovered for the first time in Lake Travis and the Highland Lakes on June 22, said Monica McGarrity, Aquatic Invasive Species team leader for the Texas Parks and Wildlife Department, at today's news conference.

The zebra mussel is a highly invasive marine animal, native to the Black and Caspian seas and finds its way to the U.S. by hitchhiking on boats, she said.

“An invasive species is a species that has impacts on our economy, our ecosystem, our human health and quality of life,” McGarrity said. “In this case, this is a bad one that has all three.”

By a zebra mussel’s ability to attach to each other forming a wide shape, the species can clog a pipe up to 18 inches in diameter, exacting costly harm to boats and any facility or pump that is using raw surface water, she said. The sharp shells housed by the zebra mussel are left on river bottoms and beaches, cutting unknowing pedestrians, creating a foul smell and affecting recreation, she said.

Zebra mussels also attach to native mussels and smother them, damaging the local ecosystem, McGarrity said.

“Now that Zebra mussels are at Lake Travis, it is essential for boaters to clean, drain and dry their boats to prevent the spread [of the mussels] and for marinas to be gatekeepers—to keep an eye out and know where boats are coming from when they are coming into a marina from another infested lake,” McGarrity said. “[Zebra mussels] spreading on boats is what’s going to result in new infestations in new river basins.”

She cautioned boaters to make sure their watercraft, including all compartments and gear, has had time to dry completely between leaving and entering different water bodies.

Texas Parks & Wildlife officials caution boaters on Lake Travis to drain and dry their watercraft to help prevent the spread of zebra mussels.[/caption]

“If you don’t have time to let [the watercraft] dry completely, we do recommend folks go to a car wash and spray it down with hot, soapy water and that will at least help to reduce the biological risk,” McGarrity said. “It’s really all about reducing the risk as much as possible.”

Kayaks are included in the precautions as they can carry zebra mussel larvae in water trapped inside the watercraft.

The transportation and possession of zebra mussels is illegal and punishable as a Class C misdemeanor with a maximum $500 fine, McGarrity said. Repeated violations could carry a higher fine, she said.

However, officials are not putting a damper on using local waterways to cool off during the summer heat.

“We certainly would not discourage folks from using these lakes for recreation,” McGarrity said. “Just simply advise folks that these are present and make sure that they don’t spread them.”