Saving endangered mussels is vital, Neves says, because mussels are the natural biological filters in the river system. They remove sediment, contaminants, and particles, ingesting some and releasing the rest into mucus strings. Some water insects feed on these strings, and the mussels themselves serve as a food source for raccoons, muskrats, river otters, and diving ducks.
Virginia's freshwater mussels live up to 70 years. They are fertile for their entire life span, after beginning reproduction at about age 4 or 5. But many species are endangered because of water pollution and disturbance or destruction of their natural habitats.
"Mussels are excellent water quality monitors," Neves says. "Because they live so long and move so little, we can take a piece of tissue, analyze for contaminants, and tell what's been going on in the water system for 50 or more years."
He and his colleagues collect gravid females, using a hypodermic syringe to harvest the larvae. They then deposit larvae onto the gills of the type of fish that particular species of mussel prefers. The larvae, which are parasitic, must attach to fish, from which they extract the nutrients required for them to transform from the larval stage to the free-living juvenile stage.
Biologists can deposit mussel larvae from one female onto hundreds of fish, whereas only about a dozen fish can become hosts for the larvae from each gravid female in the wild. The hosts are likely to be small fish that they live on the shoals, which is al
Contact: Richard Neves