Zebra Mussels Hit Perry

Zebra mussels have been found in recent years in a handful of water bodies in Kansas. El Dorado Reservoir was the first to harbor the dreaded species and they made their way downstream to the Walnut River. Subsequent discoveries have been made at Cheney Reservoir and Winfield City Lake. The most recent discovery of their invasion was confirmed at Perry Reservoir a week or so ago.

“I was surprised it jumped drainages all the way up to the Kansas River,” said Jason Goeckler, aquatic nuisance species specialist for the Kansas Department of Wildlife and Parks. “We’ve done surveys on over 12,000 boaters and studied their movements from zebra mussel infested waters to other waters and Perry didn’t even show up on the top 20 of that list.”

Zebra mussels are thumbnail-sized mollusks native to the Black and Caspian seas in Europe. Their yellowish-brown shell is D-shaped with alternating dark and light stripes. They arrived in the Great Lakes in 1988 in the ballast water of ships. They’ve slowly infested their way beyond this region and spread over the last two decades. They attach to any hard or semi-solid substrate and colonize to the point they reach inches or even feet thick.

The problems these tiny mussels pose are far reaching. Zebra mussels filter water, up to a liter per day, to eat plankton. Larval fish of all species and native mussels rely on the same plankton for their survival. They filter enough plankton the resulting water often becomes clear, something some would think a bonus.

Not true, however, as clear water often leads to algae blooms harmful to humans and wildlife. In addition, clear water may not filter harmful UV rays resulting in damage to fish eggs during their spawn.

The shells themselves pose a direct danger from incidental contact. They are extremely sharp and a misplaced step can quickly result in razor-sharp lacerations on hands and feet. I can personally vouch for that as I counted 34 deep cuts on both hands after a fall at El Dorado trying to beach my boat near our camp site a couple years ago. Protective footwear is a must in any water body where they’re found.

The mussels colonize pipes and water control structures and attach to the point where water flow is restricted or eliminated. Many bodies of water where they’ve been found are municipal water supplies for nearby cities, creating even more of a problem. Expenditures to control zebra mussels over the last decade in water intake pipes, water filtration equipment and electric generating plants are estimated at $3.1 billion.

The bad news is there is no sure-fire cure to rid a water body of its infestation. Certain chemicals will kill zebra mussels, but also all native mussels and fish species, too. A small lake in Virginia just a few acres in size did manage to eradicate zebra mussels with minimal impacts on other aquatic species using potassium chloride, but it came with a hefty price tag.

Using the same eradication efforts on a body of water the size of Perry would cost over $50 million, more than twice the annual budget of the entire Kansas Department of Wildlife and Parks.

Officials would like to prevent further spreading of the mussels to other waters.

“By going to a new drainage, it opens up a whole new area where they haven’t had to deal with zebra mussels,” Goeckler said of recreational water users. “Folks utilizing the surface water are going to have to change the way they do things (to prevent their spread to other waters).”

Zebra mussels can be transported unknowingly in boat and personal watercraft bilges, bait buckets and livewells. The larval form is the diameter of a human hair and can’t be seen without a microscope. They free-float for up to five weeks before they sink and attach to a hard surface and begin growing. Boat trailers and other recreational equipment can transport zebra mussel adults.

The proximity of Perry Reservoir to many other Kansas reservoirs is a bit alarming to officials as the potential for spreading is increased due to this fact. In addition, Perry is also upstream of two of the state’s major metropolitan areas in Lawrence and Kansas City.

“The zebra mussels we found in Perry had been there for at least three years so they’ve been there in very low densities,” Goeckler said. “But once they’re there, they can quickly colonize and populate a reservoir.”

Goeckler admits there are plenty of resources being spent nationwide to try to find a remedy to eradicate zebra mussel infestations. But a solution may not be found any time soon.

“Our goal is to keep zebra mussels contained, because the fewer water bodies there are to have to treat when that cure finally comes along, the cheaper it will be for the people of Kansas,” he said. “There are a lot of people doing research and developing new technologies fairly rapidly to address this situation because it affects every aquatic user group so there’s a large demand to figure out what we can do. I foresee a fix coming, but there’s no way to tell how far into the future it is.”

Marc Murrell can be reachedat mmoutdoors@cox.net.

(c) 2007 Topeka Capital Journal. Provided by ProQuest Information and Learning. All rights Reserved.