PIERRE, S.D. (KELO) — Some state lawmakers are concerned about zebra mussels and other invasive species spreading into more South Dakota waters. But the director for the South Dakota Division of Wildlife says there’s still no way to get rid of zebra mussels once they’re in a lake or river.

“What we do know right now is we cannot stop the spread of zebra mussels,” Tom Kirschenmann said.

The Legislature’s Government Operations and Audit Committee on Wednesday talked about whether the state Department of Game, Fish and Parks should use some of its habitat-stamp revenue to fight them.

Kirschenmann replied that the habitat-stamp law doesn’t list invasive aquatic species among the designated uses and the department is instead telling people how they can help slow the spread.

Zebra mussels can be unknowingly transported by boaters from one body of water to another when drain plugs aren’t pulled and live-wells aren’t emptied. The department advises boaters to power-wash their boats as often as possible and to raise and lower the motor’s lower unit each time.

“Our focus is on clean, drain and dry,” Kirschenmann said.

He noted that the department operates inspection stations at some lakes and in the field.

SDGFP now offers a map on its internet site showing waters known to have invasive species. They include plants, such as curlyleaf pondweed, flowering rush and didymo; invertebrates, such as zebra mussels, Asian clams, New Zealand mud snails and red-rimmed melania; and fish, such as European rudd, bighead carp, grass carp and silver carp.

Zebra mussels have been increasingly found in South Dakota in the past few years, from Pactola Reservoir in the southwest; to the lower two-thirds of the Missouri River system in the central and southeast regions; to a variety of northeastern lakes including Kampeska, Cochrane, Pickerel, Blue Dog and most recently Enemy Swim.

Kirschenmann said some neighboring states are spending millions of dollars battling aquatic invasive species “and they still have some level of spread.”

South Dakota could use the department’s entire budget — $124 million this year — and not stop infestations, according to Kirschenmann.

“We do not have that tool, if I may, to eradicate or remove a zebra mussel population from a lake once it’s there,” he said.