The Missouri Department of Conservation is warning retailers and aquarium owners to check moss balls for a potential zebra mussel infestation. Moss balls containing the invasive species have been discovered in Washington state and it’s possible they were distributed to buyers in Missouri. states a conservation department release.

Zebra mussels were first reported in Missouri in 1991 in the Mississippi River near St. Louis. They’ve since spread to the Missouri, Osage, and Meramec rivers and streams downstream of infested lakes. Lakes with confirmed reports of zebra mussels include Smithville Lake.

“Zebra mussels can clog power plants, industrial and public drinking water intakes, foul boat hulls and motors, decimate populations of native freshwater mussels, impact fisheries and disrupt aquatic ecosystems,” reports the conservation department.

Any aquarium containing moss balls infected with zebra mussels also has the potential of having zebra mussel larvae, called veligers, in its water. When aquarium water is poured down drains or if the contents are dumped into a nearby creek or lake, this could introduce zebra mussels into a new body of water.