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In the late 19th and early 20th centuries, mountains of mussels piled up along the nation's rivers, their shells as valuable to the button industry as their pearls were to jewelers. Factory workers punched as many buttons out of mussel shells as they could, before discarding them like so much stale swiss cheese. Although the button industry was lucrative for decades, eventually the bottom fell out, as mussel beds were routinely depleted.
It took years for mussel populations to recover, and they are doing so in large measure because of federally protected riparian areas such as Big South Fork National River and Recreation Area, which straddles Tennessee and Kentucky. The park contains 90 free-flowing miles of the Big South Fork of the Cumberland River and its tributaries that wend through rugged gorges and forested plateaus that provide habitat for a wide range of plants and animals. With three other national park units, the park shares the title of having the most federally listed aquatic species.
Even as mussels recovered from exploitation by the button industry, in recent decades they have been subjected to several other threats. As river enthusiasts know, whatever happens upstream affects life downstream. Mining, logging, oil and gas drilling, and other activities, outside of park boundaries, have sent pollutants down the Big South Fork and into sensitive mussel breeding sites. The park's managers have taken the necessary steps to eliminate the effects of 300 oil and gas wells and 120 coal mines within the park's boundaries and now are focusing on encouraging its neighbors to do the same.
One heavy sediment load in the river can wipe out an entire colony of mussels. Historically, this river system boasted 71 species of mussels; today, only 26 distinct species can be found here, including five endangered species: the Cumberland elktoe, Cumberlandian comb-shell, tan riffle shell, little-wing pearly mussel, and Cumberland bean pearly mussel.
"Big South Fork is a real biological treasure, but it doesn't get the kind of attention that Yellowstone and Great Smoky Mountains [national parks] do," says Steve Ahlstedt, a biologist with the U.S. Geological Survey in Knoxville.
"Most of the river is on federal property, but we have exterior forces at work outside the drainage in the form of coal mining. One bad slip-up and we're out of business."
Although mussels are small and rarely seen - often burrowed deep in a river bottom - their importance to ecosystem health cannot be overstated. Mussels are filter feeders, making them essential indicators of water quality. If mussels are in decline, chances are a river is polluted, which means that other aquatic species and animals are at risk as well. Of the 297 mussels known to occur in U.S. waters, more than 90 percent of them live in the Southeast. A full 70 percent of all freshwater mussels are listed as threatened, endangered, of special concern, or extinct by the state or federal governments.
To counteract these losses, Big South Fork National River and Recreation Area staff are working with the U.S. Fish and Wildlife Service, U.S. Geological Survey, Tennessee Wildlife Resources Agency, and two mussel hatcheries (Virginia Tech Mussel Facility and Kentucky Center for Mollusk Conservation) to propagate freshwater mussels and reintroduce them into the wild-the first such effort in a national park.
Mussels depend on the presence of fish hosts to reproduce, a delicate process in the wild that becomes even more complicated to replicate in a laboratory. Essentially, gravid female mussels (those with eggs) are taken from the river and placed in holding tanks with appropriate fish hosts. Fertilized eggs are then manually placed onto the gills of the fish, where they develop into juvenile mussels before eventually dropping off their hosts. Once they reach a viable size in the lab, the juveniles are returned to the river system. Already, about 75,000 juveniles of four federally listed species have been produced at Virginia Tech's facility and reintroduced to the Big South Fork. The goal is to spread mussel populations throughout the park so that individual species are not so vulnerable.
The symbiotic relationship of mussels and fish illustrates how important it is that a waterway and its wildlife remain healthy.
"That is what's so fascinating about mussels," says Vanessa Morel, coordinator for NPCA's Eastern Streams campaign. "Not only are they the Brita water filters of the world, but they are so closely tied to other aquatic species. They are really indicators of ecosystem health."
Although groundbreaking, the mussel propagation project is just one part of the larger effort to protect these creatures. "In wildlife management, you can't just have females have more babies and dump them back in the river," says Steve Bakaletz, wildlife biologist with Big South Fork. "That's not the problem; the problem is the pollution." Bakaletz adds that he has only recently found that certain mussel species are recovering from mining operations that ceased nearly a generation ago.
The threats are cumulative. Sedimentation from past logging, mining, agriculture, and road-building activities blankets and smothers mussel beds. Habitat alteration, such as damming, alters water temperature and flows. Some species, for example, require shallow, cool riffles and runs to survive. "If you put a dam in," Morel says, "you've slowed the water down, you've deepened it, you've decreased that natural oxygenated process, and you've created a completely different kind of habitat."
The most pressing issue at Big South Fork, however, is coal mining. After years of decline in the Tennessee Valley, coal mining has experienced a resurgence, made possible by heavy earth-moving machinery and the relative ease of newer mining practices such as mountaintop removal - a process as destructive as its name suggests. In addition to the vast alteration of natural landscapes, acidic drainage from the mining process can run into streams, where it can overwhelm sensitive aquatic species. Fish, of course, are affected by the pollution, but mussels are especially vulnerable because they don't move. "They're in these mussel beds, and they're processing everything that's coming downstream," Morel explains.
Recently, a federal interagency report on Appalachian surface mining found that 724 miles of streams had been buried by mining spoils between 1985 and 2001 and that another 1,200 miles of streams were in danger from mining over the next decade. Yet new regulations on sulphuric emissions from coal-fired power plants might have the ironic effect of increasing the coal mined in the region. As the Tennessee Valley Authority installs devices to remove sulphur (better known as scrubbers) at its plants, it will likely increase its efforts to mine locally instead of buying less-sulphuric coal from western mines as it has in recent years.
Near the Big South Fork, mining companies are also loosely interpreting the practice of "remining," which allows mining to take place in an abandoned area as long as it is reclaimed afterwards. Morel says that most recent remining proposals call for new mining in these areas and that even reclaimed sites fail to support the forest communities that were present before the mining took place.
Abandoned mine lands and incentives for remining will be debated in the upcoming reauthorization of the Abandoned Mine Land Reclamation Fund, which was scheduled to expire September 2004. The fund has allowed for the cleanup of about 10,000 sites across the country, but one of the reauthorization bills before Congress would allow mining companies to use money from the fund to post their performance bonds if the proposal contains some remining. This would pave the way for new mining in already degraded and sensitive areas.
One proposal now under consideration could recover as much as 70 million tons of coal from the Koppers Coal Reserve, a 53,000-acre area in eastern Tennessee. By comparison, in 2002 only three million tons of coal was produced in the entire state of Tennessee. If the Koppers Coal project moves forward, the impact on natural resources including mussels and other aquatic species will be difficult to fathom.
Particularly disheartening for the region's mussel advocates is the fact that massive mining projects could reverse decades of hard-won recovery in a relatively short time. Many agree that the Big South Fork is healthier than ever and that mussel species have been expanding their territory, even without the propagation project.
"Thirty years ago everyone assumed that the river was destroyed because of the mining, and it does have a tremendous amount of mining waste in it," says Steve Ahlstedt. "But it's coming back dramatically, and it has the best mussel fauna that's left in the whole Cumberland River system - and you're talking about many hundreds of miles of river."
Both Ahlstedt and Bakaletz, who have worked together on the propagation effort, understand that mussel recovery is a slow and unpredictable process. "Natural survival of mussels, out in the wild, is probably only as little as less than 1 percent," Ahlstedt says. "It's a matter of putting out as many as you can get, into the thousands, and you keep doing it over time until populations become self-sustaining. It can take a lifetime of work to restore mussels back into the wild."
An ongoing challenge for biologists and environmentalists is convincing federal agencies and others that mussels are worth saving. "Mussels are constantly ignored because they are down amongst the gravel and the sand," Ahlstedt says. "But if you have good mussel populations, you'll have good fish fauna, good insect fauna, and good water quality."
Going forward, NPCA will continue to raise awareness about the importance of mussels and the dangers of mining and other threats. The organization is also advocating that the Abandoned Mine Land Fund be reauthorized in a way that protects natural resources. For her part, Vanessa Morel believes there is a growing understanding of the connection between aquatic biodiversity and water quality and our own quality of life.
"There is a generation that has seen the before and after [of stream degradation]," Morel says. "If you don't have these critters in the streams, chances are you won't be fishing in them anymore, and you can't eat what you catch if you do fish there. If we can support efforts like the mussel propagation, I think they have a chance. This really is the test case. The fate of mussels in the Southeast hinges on it."
Based in Arlington, Virginia, Kim A. O'Connell last wrote for National Parks about visiting Lewis & Clark sites by train.
