Pearls of the Gasconade

Sue Bruenderman and Scott Faiman float face-down in the chilly waters of the Gasconade River. Outfitted in wet suits and snorkeling masks, the Conservation Department researchers are doing what looks like a crawdad crawl along the streambed. Even though they wear weighted diving belts, they struggle to keep from being swept away by the swift current. Both run their hands along the bottom hoping to find mussels that have burrowed into the gravel.

Suddenly Bruenderman is on her feet, wavering as the water surges against her legs. She has pushed her snorkel mask onto her forehead. Cupped in her hands are nine brownish mussels, each one no bigger than a penny. If you're hunting for mussels, finding this many live ones seems like a good start. "They're Asian clams," says a disappointed Bruenderman, who is the state malacologist, an expert on mussels. As Missouri's native mussels have declined, this adaptable exotic species has flourished and competes with native species.

Minutes later Faiman, a fisheries research assistant, comes out of the water with better news. "I've probably seen 40 mussels," he says, hoisting his mesh bag full of the specimens he's collected. He reels off the list of species--pocketbooks, muckets, purple wartybacks and ellipses.

Despite Faiman's good luck in this spot, mussels are at the leading edge of an alarming decline hitting mussels and other aquatic animals native to Missouri--fish, crawfish, amphibians and semi-aquatic reptiles. Similar trends are reported nationwide. If the trend isn't reversed, more than a few will almost certainly disappear from the state or vanish into extinction.

Highly tolerant species, such as the Asian clam, are thriving. Others that make up much of the state's native aquatic fauna are increasingly threatened. Today, approximately 28 of Missouri's 65 mussel species are rare or declining and vulnerable to disappearing from the state.

Mussels are an important link in the food chain along the stream. Muskrats, otters and raccoons feed on them, as do some fish species. Mussels also filter water through their gills, storing sediment and contaminants in their bodies and shells. They can be thought of as nature's vacuum cleaners. They also are an important indicator of habitat and water quality. Water quality affects not only stream life but also public and private water supplies statewide.

Missouri's aquatic fauna is rich and distinctive. Few other states can boast of having two of the continent's greatest rivers and the diversity of