Three more Texas lakes are being added to the list of lakes affected by zebra mussels. Lake Livingston, Eagle Mountain Lake and Lake Worth all tested positive for zebra mussels. As we head into the Independence Day weekend, these new findings serve as a good reminder to boaters to “Clean, Drain and Dry” their boats, trailers and gear every time they travel from one lake to another to prevent the spread of zebra mussels and other invasive species.
Sampling funded by the Trinity River Authority and conducted on Lake Livingston June 22-23 by the United States Geological Survey (USGS) confirmed the presence of zebra mussels. Dr. Christopher Churchill with the USGS found four adult zebra mussels attached to settlement samplers that were deployed at three different locations throughout the lake. Churchill stated that “At this point in time, it is not possible to determine whether the zebra mussels in Lake Livingston are the result of reproduction within the lake or if they are the result of downstream dispersal or overland introduction.”
Likewise, the Tarrant Regional Water District (TRWD) has been monitoring Eagle Mountain Lake and Lake Worth for the presence of zebra mussels. Both lakes are downstream of Lake Bridgeport, which is known to be infested. Plankton samples collected by TRWD on May 18 found what appeared to be zebra mussel larvae. Those specimens were later confirmed by the Texas Parks and Wildlife Department (TPWD) through genetic analysis. Additional monitoring conducted on June 28 by TRWD and TPWD resulted in the finding of several adult zebra mussels in both Eagle Mountain Lake and Lake Worth.
Since zebra mussels were first found in Texas in 2009, six Texas lakes in three river basins are now fully infested, meaning that they have an established, reproducing population. Zebra mussels have been found on occasion in six other Texas lakes but at this time it is uncertain if those lakes have a viable reproducing population. See the Texas Parks and Wildlife Department website for details on affected water bodies.
The rapidly reproducing zebra mussels, originally from Eurasia, can have serious economic, environmental and recreational impacts on Texas reservoirs. Zebra mussels can clog public-water intake pipes, harm boats and motors left in infested waters, completely cover anything left under water and litter beaches with their sharp shells.
In Texas, it is unlawful to possess or transport zebra mussels, dead or alive. Boaters are also required to drain all water from their boat and on-board receptacles before leaving or approaching a body of fresh water in order to prevent the transfer of zebra mussels that might be trapped inside. This regulation applies to all types and sizes of boats whether powered or not: personal watercraft, sailboats, kayaks/canoes or any other vessel used on public waters. Movement from one access point to another on the same lake during the same day does not require draining.
“Boaters’ actions are absolutely vital to help prevent zebra mussels from spreading to any new river basins. Three simple steps can help stop them and help you stay within the law,” said Brian Van Zee, Inland Fisheries Regional Director for TPWD. “Clean, drain and dry your boat every time you leave a body of water.”
TPWD and a coalition of partners have been working to slow the spread of zebra mussels by reminding boaters to clean, drain and dry their boats, trailers and gear before traveling from one waterbody to another. The partners in this effort include: North Texas Municipal Water District, Tarrant Regional Water District, City of Dallas Water Utilities Department, Trinity River Authority, San Jacinto River Authority, Sabine River Authority, Brazos River Authority, Guadalupe-Blanco River Authority, Lower Colorado River Authority, Upper Trinity Regional Water District, Water Oriented Recreation District of Comal County and the Lady Bird Johnson Wildflower Center.
More information about zebra mussels can be found online at www.texasinvasives.org/zebramussels.