Mineral Wells Index, Mineral Wells, TX

April 7, 2014

Zebra mussels bad news


Mineral Wells Index

— By TODD GLASSCOCK



Some muscles are alluring. Other mussels, when cooked in dishes like linguine and clams, for instance, are tasty. Boaters heading out to area lakes and rivers this time of year, however, should be aware that one species of mussel – the zebra mussel – is not alluring or tasty, and can pose a threat to the environment and to native species.

These small freshwater creatures, originally from the Balkans, hitchhike from waterway to waterway on boats and other watercraft, said biologist Tom Lang with the Texas Parks and Wildlife Wichita Falls District Fisheries Office that oversees Possum Kingdom Lake, Lake Palo Pinto and Lake Mineral Wells.

They are more than a nuisance, he said. They reproduce rapidly, usually forming large clusters between 30,000 and 1 million, and can encrust boats, clog pipelines at water pump stations and create other environmental hazards.

Their shells are also razor sharp and can injure swimmers, Lang said.

Because they are filter feeders, and have no native natural predators, he said, they threaten the food chain from the bottom up, rapidly eating up and covering vegetation and other nutrient-rich food sources that small fish and other aquatic animals rely upon.  

“When you cover the bottom, you lower the top,” he said of the mussels interfering with the food chain.

While most fish won't eat them, some do, he said, but they are largely indigestible and often survive through the fish's digestive tract to be expelled back into the water.

The mussels can be easily transported from waterway to waterway by boats and other watercraft, he said, and this time of year, as more boaters hit area lakes and rivers such as Possum Kingdom and the Brazos for fishing and recreation, these waterways have a greater risk of mussel invasion.

And this is why boaters should carefully clean, dry and drain their vehicles, he said.

When not cleaned, dried or drained, boats can be infested anywhere from the anchor to the bilge, and because the mussels' larvae are microscopic, they can't be seen by the naked eye. Additionally, the larvae are free swimmers and can travel quickly by water.

Adults grow no more than about 1 ½ inches, he said, and develop a distinctive zebra-like striped shell.

In its Brazos Basin newsletter, the Brazos River Authority said boaters in 47 counties, including Palo Pinto and Parker, are required “to drain water from watercraft approaching or leaving public waterways.”

“The move [to require boaters to drain their craft] comes a few months after the destructive bivalves were confirmed for the first time in the Brazos basin, at Belton Lake in Bell County,” the newsletter reads. “Other Texas lakes where zebra mussels have been found include Bridgeport, Lavon, Lewisville, Ray Roberts and Texoma.”

Currently, area lakes haven't been affected, Lang said. “Thankfully, as of this time we have not received reports of, or detected in our sampling, zebra mussels in Palo Pinto, PK or Lake Mineral Wells.”

Scott Blasor, secretary-treasurer of the Palo Pinto County Municipal Water District 1, said the district has done a risk assessment regarding the mussels, noting that if the lake were affected, the mussels could block up pumps and pipelines and would have to be cleared.

The mussels first infested the Great Lakes in the 1980s, transported by ships from Europe, and have spread south to Texas, Lang said. Lake Texoma was the first lake discovered to have the mussels in 2009.

He said Texas Parks and Wildlife encourages everybody to get involved to help keep the mussels from spreading. “It takes everybody to do the right thing and be vigilant.”