Kansas wildlife officials have confirmed the presence of zebra mussels in still another lake.

The Department of Wildlife, Parks and Tourism said Thursday the tiny mollusks were spotted by an angler at Lake Shawnee in Topeka. The discovery brings to 19 the number of Kansas lakes infested by zebra mussels, which quickly grow into huge populations and clog intake pipes for public water systems.

The agency says it found zebra mussels at multiple locations in the 416-acre lake owned by Shawnee County.

Zebra mussels are usually introduced into lakes after attaching themselves to boats or winding up in bait buckets. Kansas officials urge anglers and boaters to clean, drain and dry their boats between uses and use wild-caught bait only in the body of water where it was caught.