Zebra mussels detected at Medina Lake, Lake Placid designated as âinfestedâ Zebra Mussels. Courtesy: Texas Parks and Wildlife By KLTV Digital Media Staff | March 16, 2021 at 10:27 AM CDT - Updated March 16 at 10:27 AM AUSTIN â The Texas Parks and Wildlife Department (TPWD) has detected invasive zebra mussels at Medina Lake and Lake Placid will be re-classified as âfully infested.â Infested status signifies that there is now evidence of an established, reproducing population of zebra mussels in the lake. The detection in Medina Lake, located near Bandera, marks the first introduction of invasive zebra mussels in the San Antonio River Basin. On Feb. 11, a member of the public submitted a report with a photo to TPWD of a zebra mussel located at a boat ramp near the mouth of Habyâs Cove. Shortly after the winter storms, TPWD staff conducted searches at the site where the original mussel was found and near Red Cove Marina. Biologists located two zebra mussels attached to rocks along the shoreline near the site where the first mussel was discovered.