Zebra mussels menace Missouri's Lake of the Ozarks

Joyce L. Miller

Diligence will be the key to keeping the zebra mussel population under control now that they have taken up residence in the lake.

As the summer season draws to a close and boaters get ready to winterize their vessels, lifts or make late season repairs to docks, conservation/resource officials say its a good time to check for any zebra mussel infestations. Especially on boats that will be trailered to other waterways for the winter.

Public awareness and education efforts continue to be the most effective means of preventing the spread of the nuisance species.

The lake had managed to avoid the infestation of zebra mussels for several years. There had been several close calls where boats arrived and while waiting to be launched zebra mussels were found attached to hulls or intake valves. Those boats were caught before hitting the water by employees at marinas who knew what they were. 

It wasn’t until 2006 that first mussels were found in the water.

Since then there has been a scattering of reports, primarily from the Gravois Arm of the lake to Bagnell Dam but there have been occasional reports coming from upstream. A few were also found on the Osage River.

The largest concentration was discovered last summer when a large colony of mussels were found attached to the hull of one of the excursion boats docked near Bagnell Dam.  

According to the Missouri Department of Conservation, once the zebra mussels arrive, there is no affordable way to get rid of them. They pose a serious threat not only to boats and structures on the water but to native mussel species. Once eggs are laid by adult mussels, the nuisance species spreads.

MDC is continuing their efforts to raise the awareness of boaters, asking marinas to check incoming boats. MDC has been working on getting the message out to boaters who bring their watercraft in from other places to be aware of the problem and look for any signs of infestation before launching into any waterway.

The mussels have moved into streams, lakes and rivers across the country. 

One of the reasons the lake has been spared the threat of the zebra mussel until now has been due to the efforts of the public and marinas keeping an eye out for the mussels.

Stoner said MDC has kept warning signs at various locations around the lake, including all public access ramps.

The goal now is to continue efforts to educate the public and evaluate the extent of the infestation as well as try to prevent the spread.

According to information provided by the MDC, there’s no question the mussels can survive in the lake and create havoc for the environmental balance of the water, cause extensive damage to boats and docks and could  pose a threat to the operation of Bagnell Dam.

The small mussels adhere to boats, docks and other structures, encrusting any solid surface. Thousands can be found on a single square foot of space. Because of their huge numbers, the mussels clog intake valves and create numerous problems for hydroelectric power plants such as the one at Bagnell Dam.

The mussels were first found in Missouri in 1991. They were originally carried to this country from eastern Europe on an ocean vessel that dumped them into the Great Lakes.

Contact this Lake Sun Leader reporter at joycem@lakesunleader.com