- news, features, articles and disease information for the fish industry


Invasive Zebra Mussels Found in Texan Lakes

23 September 2013

US - Zebra mussels, a destructive invasive species that originated in Eurasia, have been found in Lake Belton in Central Texas.

Texas Parks and Wildlife Department Executive Director Carter Smith signed an order adopting an emergency rule to add lakes Belton and Stillhouse Hollow, and portions of the Leon and Lampasas rivers to the list of water bodies covered by special regulations intended to control the spread of zebra mussels.

Under these special regulations, boaters who drain their boats and gear will not be considered in violation of rules prohibiting possession of zebra mussels.

“The Lake Belton discovery underscores how critical it is for boaters all across Texas to get informed and involved to help stop the spread of zebra mussels,” said Brian Van Zee, TPWD Inland Fisheries regional director based in Waco.

“Unfortunately, zebra mussel larvae, called veligers, are not visible to the naked eye. You could be transporting them on your boat and not even know it. This is why it’s particularly important to always Clean, Drain, and Dry your boat and gear before heading to another water body.”

A Texas Mussel Watch volunteer was looking for native mussels along the shores of Lake Belton on September 18 when she found a Giant Floater that had a small mussel attached to its shell. Suspecting that it might be a zebra mussel she reported it to the Texas Parks and Wildlife Department. The following day, TPWD confirmed that the small mussel was in fact a zebra mussel.

A follow up survey conducted by TPWD after the September 18 discovery revealed that zebra mussels are well established in Lake Belton and are found throughout the lake. In fact, three size classes of zebra mussels were found in Lake Belton indicating that they were likely introduced to the reservoir sometime in 2012.

“This is very discouraging news for a several reasons,” said Van Zee. “Not only does this mark the first time that zebra mussels have been documented in the Brazos River basin, this new infestation is nearly 200 miles south of where zebra mussels are currently found in Texas. Unfortunately, this means that lakes in the central portion of the state are at even greater risk.”

Also, TPWD’s monitoring of 23 other Texas reservoirs during the spring and summer revealed the possible presence of zebra mussels in two additional reservoirs: Lakes Worth and Joe Pool.

While zebra mussel DNA was detected in these two reservoirs, no adult zebra mussels or veligers have been found in either water body.

“DNA test results for both lakes were weak positives, and the fact that the presence of zebra mussels could not be confirmed by other methods means that these two lakes should be considered ‘suspect’ until further testing,” said Van Zee.

Rules, necessitating boaters to drain all water from their vessels before leaving water bodies with confirmed populations of zebra mussels, have already been instituted for Lakes Texoma, Lavon, Ray Roberts, Lewisville, Bridgeport, Eagle Mountain and Worth; parts of the Red River; parts of the Elm Fork of the Trinity River; and all impounded and tributary waters of the West Fork of the Trinity River above the Lake Worth dam.


TheFishSite News Desk

Our Sponsors


Sustainable Aquaculture Modular Courses AVAILABLE NOW - University of St Andrews

Seasonal Picks

Know Your Freshwater Fishes - 5m

Aquacullture Webinars from TheFishSite - Sign Up Now