Zebra Mussels Confirmed in Coffey County Lake

Officials with the Kansas Department of Wildlife, Parks and Tourism and the Wolf Creek Generating Station announced Friday that zebra mussels have been found in Coffey County Lake. Officials knew it was a matter of time before zebra mussels appeared in the lake near Burlington because the aquatic nuisance species (ANS) had been detected in Marion Reservoir three years ago. The Cottonwood River flows from Marion Reservoir into the Neosho River, which then fills John Redmond Reservoir. Coffey County Lake, which is the cooling lake for Kansas‘ only nuclear power plant, gets its water from John Redmond. The larval stage of zebra mussels, called veligers, are microscopic and free-floating in water. Transmission downstream from an established population is the only method of spreading zebra mussels that is inevitable.

Wolf Creek officials were prepared for this event and have implemented procedures and equipment to ensure that zebra mussels won’t interfere with the generating station’s operations.

Zebra mussels are small, bi-valve mollusks with striped shells. They are native to the Black and Caspian seas of Western Asia and Eastern Europe and have been spread across the world via shipping. They were discovered in Lake St. Clair and the Detroit River in 1988. Zebra mussels quickly spread through out the Great Lakes and to many inland rivers including the MississippiIllinoisOhioTennesseeArkansas andHudson. They first appeared in Kansas in 2003 when they were discovered in El Dorado Reservoir. Public education programs were designed to inform boaters about the dangers of zebra mussels in our waters and ways to prevent spreading them. However, zebra mussels have been confirmed in more the a dozen Kansaslakes in the past nine years. Moving water in boats and bait buckets was identified as a likely vector and recently, KDWPT established stringent regulations regarding the use of wild-caught bait, as well as prohibiting the movement of live fish from lakes where zebra mussels have been found.

Although related, zebra mussels differ from our native mussels in several important categories. Perhaps the most important is their ability to produce very large populations in a short time. Unlike native mussels, zebra mussels do not require a host fish to reproduce. A large female zebra mussel is capable of producing 1 million eggs during the reproductive season. Once fertilized, eggs develop into microscopic veligers. These veligers cannot be seen by the naked eye and can be contained by the thousands in very small quantities of water. Veligers passively float within the water for up to two weeks before they settle out as young mussels. These young mussels quickly grow to adult size and reproduce during their first summer of life, thus adding to the problem of extremely dense populations.

After settling, zebra mussels develop byssal threads that allow the shells to attach to hard surfaces such as rocks, piers, and flooded timber. They also attach themselves to pipes, water intake structures, boat hulls, propellers, and lower units of out board motors. As populations continue to increase in these areas, they can clog intake pipes and prevent water treatment plants and electrical generating plants from drawing water. In 2012, two Kansas communities, Council Grove and Osage City, experienced water shortages because of zebra mussel infestations before water intake structures could be cleaned up. Removing large quantities of zebra mussels to ensure adequate water supplies can be labor-intensive and costly.

Zebra mussels are just one of the non-native aquatic species that threaten our waters and native wildlife. Boaters and anglers are reminded to follow basic precautions to stop the spread:

• Clean, drain and dry boats and equipment between uses

• Wild-caught bait may only be used in the lake or pool where it was caught

• Live fish may not be moved from waters infested with zebra mussels or other aquatic nuisance species

• Livewells and bilges must be drained and drain plugs removed from all vessels prior to transport from any Kansas water on a public highway