December 2013
Homeplace & Community

Miniscule Mussels

A Key to Waterway Restoration?

Important study underway at Alabama Aquatic Biodiversity Center

Dr. Paul Johnson, resting his right arm on a book about mussels, examines two mussel shells at his Perry County office.  

Mention Alabama to most people in America and they’ll probably think of football players with lots of muscles, not little mussels living underwater.

Unlike large athletes who represent the state on the gridiron, tiny aquatic varieties now are part of an important study that, one day, could help clean polluted waterways.

It’s being done at the Alabama Aquatic Biodiversity Center in Perry County where the mussels are being babied by Paul Johnson who directs the facility.

Mussels don’t have four legs because they are invertebrate animals similar to saltwater clams, but these are found in rivers and streams.

Johnson is a scientist who believes mussels could hold the key to an environmental breakthrough.

"Using these creatures to promote ecological restoration of our waterways will improve water quality and quantity, thereby reducing multiple regulatory burdens," Johnson said.

He said clean-up efforts in critical watersheds not only support the needs of rare species, "but they have economic impacts far beyond wildlife."

To put it more succinctly, Johnson said, "The cleaner your water source is, the cheaper the treatment process."

Mussel existence in Alabama is a well-kept secret known mostly by scientists and environmentalists who study them for a living.

What few know is that Alabama has one of the richest and most diverse groups of mussels in the world with 181 species reported by state authorities.

However, historic modifications and pollution combined to cause 26 species to go extinct. Another 15 were eliminated from state waters and 55 species were listed as endangered or threatened by the U.S. Fish and Wildlife Service.

Reports show the Tennessee River coursing through the upper regions of Alabama has the most important source of commercial mussels in the world.

Besides benefitting some aquatic species that like to dine on mussels, the mussels’ shells add up to millions of dollars in exports.

Geology and history combined to make Alabama home for mussel growth and production, dating back millions of years when the northern reaches of the Gulf of Mexico extended to parts of central Alabama.

  This bucket contained hundreds of tiny mussel shells produced at the Aquatic Biodiversity Center in Perry County.   Paul Johnson hauls up a bucket filled with mussels produced at his research facility in Perry County.

"Basically, Alabama was part of an inland sea with the Tallapoosa, Cahaba, Coosa and Warrior rivers all isolated from each other," Johnson explained. "It all added up to an explosion of fauna and led to a unique biodiversity."

The Alabama Department of Conservation and Natural Resources dedicated Johnson’s facility in October 2010 with then Governor Bob Riley on hand for the big event.

The site was last operated by the U.S. Geological Survey which closed in 1995. Four years later, the property was deeded to the state of Alabama and the division of Wildlife and Freshwater Fisheries began renovations in 2005.

Fisheries Section Chief Stan Cook said, at the time, conservation efforts led by Johnson affect everyday issues "such as the quality of our drinking water."

"Improving the water quality in Alabama also improves game-fish habitat - a win-win situation for everyone," Cook said. "This is just one piece of the puzzle that helps to improve the quality of life for all Alabamians."

In addition, 64 mollusk and fish species are considered threatened or endangered by the U.S. Fish and Wildlife Service.

Top to bottom, the displaying female Alabama Lampmussel (Lampsilis virescens) from the Paint Rock River in Jackson County. The species is federally endangered and currently occupies about 20 miles of riverine habitat in the Paint Rock River and Emory River, Tenn. AABC restoration efforts have reintroduced the mussel into several Tennessee River basin sites in an effort to establish new populations. To date, over 10,000 animals have been stocked into four different rivers in both Alabama and Tennessee. If the species becomes established, it may be possible for the USFWS to down list the mussel. The Tennessee Wildlife Resources Agency is a partner in restoration efforts for this species. The female is luring for smallmouth bass, the host fish for the juvenile mussels. The Plicate Rocksnail (Leptoxis plicata) is restricted to the Black Warrior River basin, and historically occupied some 500 miles of riverine habitat. In 1998, the snail was listed as endangered by the U.S. Fish and Wildlife Service because habitat modification and water pollution throughout the Black Warrior basin left about 20 miles of habitat in the Locust Fork in Jefferson County. Restoration efforts completed by the AABC have initiated a new population in Blount County. Eventually, if water clean-up efforts are successful, the species could be returned to the Mulberry Fork.  (Credits: ADCNR)  

That’s one reason for the hiring of Johnson who already had more than 14 years of experience in the development of artificial propagation and culture techniques for freshwater mussels, snails and some fishes.

A Kentucky native who earned his doctorate in Zoology and Fisheries at LSU in 1995, Johnson arrived in Alabama after serving as director of the Tennessee Aquarium Research Institute.

Among his initial efforts as director of the Perry County facility was to launch a recovery function through surveys, culture and research.

"Culture work is most visible, but we also do a good number of research projects with universities," Johnson said.

A good way to inform the public about the importance of mussels and their aquatic cousins is comparison - comparing them to underwater vacuum cleaners.

In basic terms, mollusks filter water through their bodies by sucking it in and then pulling out bacteria and suspended solids.

"A big mussel can filter several dozen gallons of water a day," Johnson stated. "When our rivers were modified and polluted, we lost the natural filtration component of the rivers."

As a way to turn that problem around, Johnson spends much of his time inside at his rural laboratory or outside where tiny, cultured mussels are kept underwater in large buckets.

In a way, the buckets serve as an underwater incubator and Johnson provides plenty of TLC to the fledgling fish that the young mussels use for hosts, discarding any fish that don’t make it and those not showing good signs of life.

Nick Nichols, assistant chief of fisheries for the state Department of Conservation, said research at the Perry County facility will go a long way in solving some of the problems associated with "conserving and reintroducing aquatic species to streams and rivers."

"Dr. Johnson is doing a great job and I’m confident his operation will produce important results," Nichols said. "What he’s got there is bigger than any federal operations doing similar work."

Nichols said one important goal of the research "is to understand the species life cycle and bring them in from the wild, so to speak."

He indicated that Johnson’s research is a long-term project and not expected to bring about an overnight conclusion, "but we’re confident it will be successful."

"What Paul’s doing with mussels, snails and other species only started late in the last decade," Nichols said. "It takes a while for success because specific, unique needs are involved."

One of Johnson’s priorities is to help remove aquatic species from U.S. Fish and Wildlife Service’s endangered lists "and I feel we’re making good headway in that direction."

When he’s not hard at work at his office, in his lab or outside where the mussels are growing in those big buckets, Johnson and his family are enjoying country living.

"We’re a long way from big cities, but we’re not concerned about that," he said. "It’s kinda nice to have a bald eagle nesting in your backyard."

Alvin Benn is a freelance writer from Selma.