State wildlife managers have detected fragments of invasive zebra mussel DNA in a stretch of the Colorado River near Moab, marking the first time DNA from the species has been found in the Utah portion of the river. The discovery has prompted the Utah Division of Wildlife Resources to urge watercraft users to take extra precautions to prevent the spread of the invasive mussels.
DNA Detection Near Moab
The detection occurred through environmental DNA testing conducted during June and July of 2026. An environmental DNA autosampler, deployed 14 river miles downstream of Moab near the Potash Boat Ramp, collected daily samples that were analyzed by the U.S. Geological Survey. Of the 22 samples tested during that period, four tested positive for zebra mussel DNA, according to reports from Utah News Dispatch and Gephardt Daily.
While the presence of DNA indicates an animal is present somewhere upstream, officials noted the testing does not confirm that living mussels are currently in the sampled area. Previous environmental DNA and veliger samples collected from other locations along the Colorado River in Utah during the spring and summer of 2026 did not return positive results.
Threat to Infrastructure and Ecosystems
Zebra mussels, which originated in Russia, pose a significant threat to aquatic ecosystems and infrastructure. Once established, these mussels can clog pipes and water infrastructure, create recreation hazards by covering rocks and beaches with razor-sharp shells, and alter entire ecosystems. The species is considered an emerging threat in the Upper Colorado River basin following a documented infestation near Loma, Colorado, in 2025.
Lt. Bruce Johnson of the Utah Department of Natural Resources Law Enforcement Aquatic Invasive Species Statewide Operations stated that it is critical for users of boats, paddleboards, kayaks, and other watercraft to adhere to all laws and follow cleaning protocols. He emphasized the importance of cleaning, draining, and drying watercraft to prevent the species from spreading further into Utah.
Boater Responsibility and Prevention
Trina Hedrick, the Utah Division of Wildlife Resources sportfish coordinator, described the discovery as a reason to take the threat seriously. "There is no time like right now to get serious about this threat," Hedrick said in a prepared statement.
Hedrick noted that because nonmotorized boaters—including those using rafts, canoes, and paddleboards—are primary users of the Colorado River, they serve as the first line of defense in reducing the risk of transporting the species to other Utah waters. She encouraged all boaters to clean, drain, and dry their vessels when moving between different lakes or rivers.
Statewide Prevention Measures
To combat the spread of invasive species, Utah requires all river users, including those with nonmotorized craft, to complete an annual mussel-aware boater course. Additionally, owners of motorized boats must pay an annual aquatic invasive species program vessel enrollment fee, which funds state efforts to manage and prevent the spread of such pests.
The Division of Wildlife Resources and partner agencies will continue to collaborate with the U.S. Geological Survey, the National Park Service, and the Bureau of Land Management to monitor the status of zebra mussels in the Colorado River within the state.
Monitoring History
The Utah Division of Wildlife Resources began sampling for invasive mussels in the Colorado River in 2025, monitoring the area from the state line to Moab.
