Sign up for the iWire to get breaking , events and the species spotlight.

Invaders of Texas Login

Forgotten password?

Photographer: Amy Benson
Source: U.S. Geological Survey
Cover photo: TPWD Photo Archives

Zebra Mussels

Dreissena polymorpha

Origin: Native of Russia

Impact: The zebra mussel is a highly invasive, small freshwater mussel that multiplies rapidly and can cause tremendous environmental and economic damage. Their larvae are microscopic, and the adults are usually less than 1 1/2 inches long. Zebra mussels are usually found in large clusters, have a salient zebra-like striped pattern on their shells, and lie flat on a smooth surface, unlike many other mussels. According to the online National Atlas of the United States, "Once zebra mussels become established in a water body, they are impossible to eradicate with the technology currently available."

The spread of zebra mussels: Originally from the Balkans, Poland and the former Soviet Union, zebra mussels are firmly established in Europe and have invaded much of the U.S. On April 3, 2009, the first adult zebra mussel in Texas waters was confirmed in Lake Texoma. Zebra mussels are currently in Lake Texoma, Lake Ray Roberts, Lewisville Lake, Lake Bridgeport, Lake Lavon, Lake Waco and Lake Belton. They have also been found on isolated occasions in Lake Ray Hubbard, Lake Grapevine, Lake Fork, Lake Tawkoni, the Red River below Lake Texoma, the Elm Fork of the Trinity River below Lake Ray Roberts, and Sister Grove Creek. Experts fear they could spread throughout the Red and Trinity River systems as well as much of Texas. Both river systems extend southward to the Gulf of Mexico.

Learn More:
Hello Zebra Mussels. Goodbye Texas Lakes.
Species Profile Page

Report Form

If you have spotted Dreissena polymorpha (Zebra Mussels), use this report form to send an email to the appropriate authorities. All fields marked with an asterisk (*) are required.

Your Name*


Phone Number*

Street Address*



Zip Code*

Location of Observation*
Enter Latitude and Longitude in decimal degrees or Click the Choose Location button and navigate to the point where the specimen was observed on the Google Map to automatically enter Latitutde and Longitude.

Latitude: Longitude:

Did You Collect a Specimen?*
Yes or No.

Host Plant
If applicable, what is the host plant?

Comments: Describe the species, impact, infestation or generally what you are seeing.

Image Upload*
Please upload a photo of the specimen or the site where the specimen was seen. Image file must be a .jpg, .gif or .png format.