The Texas Parks and Wildlife Department announced Sept. 1 that it has elevated the invasive zebra mussel status of Fort Phantom Hill Lake, near Abilene, to fully infested. According to the agency’s Sept. 1 news release, the designation means an established, reproducing population of the invasive mussels is now confirmed in the lake, which had carried a positive designation since September 2025.
The change extends a pattern that has concerned state biologists. According to the release, invasive mussels have now spread to 40 Texas lakes, with 36 of them fully infested, and the species has been moving into lakes in the western part of the state in recent years.
TPWD said that in July 2026, zebra mussel larvae were found in plankton samples collected from multiple sites around the lake in the spring and verified with DNA lab analysis. Staff then conducted a lake-wide search at shorelines, boat ramps and other infrastructure and found zebra mussels of multiple size classes, which the agency said confirmed an established reproducing population. The lake’s initial positive designation followed an August 2025 report of a single adult zebra mussel next to a dock and two confirmed larvae in a nearby plankton sample, the release said.
“Unfortunately, this confirmation of an established population of zebra mussels at Fort Phantom Hill Lake is part of a trend in recent years of a spread of this highly invasive species to lakes in the western part of the state,” Monica McGarrity, TPWD senior scientist for aquatic invasive species, said in the release. She urged boaters to clean, drain and dry their boats to prevent the spread of zebra mussels and other aquatic invasive species.
The agency said zebra mussels alter lake ecosystems, harm native species, damage boats and water supply infrastructure, and litter shorelines with sharp shells. Matthew Dane, water utilities director for the City of Abilene, said in the release that the confirmation gives the city important information for managing the lake as a drinking-water source and that continued monitoring and inspections will guide long-term protective measures.
Brian Van Zee, TPWD inland fisheries deputy division director, said in the release that far more lakes have not been invaded and remain at risk, and that each boater who cleans and drains a boat before leaving a lake and lets compartments and gear dry completely at home can make a big difference.
TPWD noted that transporting prohibited aquatic invasive species in Texas is illegal and punishable by a fine of up to $500 per violation, and that boaters must drain all water from their boats before leaving or approaching a body of fresh water. The agency asked anyone moving equipment stored in an infested lake to call 512-389-4848 for decontamination guidance, and asked the public to report suspected new infestations to aquaticinvasives@tpwd.texas.gov.