Warsaw, Mo. – Zebra mussels, a harmful invasive species, are now present in all arms of Truman Lake, said Mike Bayless, fisheries management biologist for the Missouri Department of Conservation (MDC). Evidence that mussels might be present in the lake was found in prior years. But inspections conducted by the U.S. Army Corps of Engineers in recent weeks have determined that they are now fairly widespread in the lake, Bayless said. This makes it imperative for boaters and anglers at Truman Lake to take steps to avoid spreading zebra mussels to other waters.