WASHINGTON — Dramatic before-and-after photos showing how freshwater mussels cleaned a tank of badly polluted Potomac River water in a matter or hours are encouraging signs that water quality near Washington could be significantly improved if the animals are reintroduced into the river by the millions, according to the Potomac Riverkeeper Network.
The 2-year-old Lamp Mussels, a freshwater cousin of oysters, were recovered this week from a small demonstration project being conducted by the Potomac Riverkeeper Network at the National Harbor Marina in Prince George's County, Maryland.
Divers checking the mussel project under the docks found conditions so polluted and murky they were nearly blinded while trying to recover samples.
But in a little over an hour, the mussels brought to the surface significantly clarified an aquarium tank filled with dirty water that was placed on the dock.
The mussels are filter-feeders that sustain themselves by straining out algae and other pollutants as nutrition.
"The goal is to have 50 million mussels. This is just a start," said Potomac Riverkeeper Dean Naujoks.
"We started with 23 last year. The long term goal is to create a hatchery and start getting these mussels to start breeding on their own in the Potomac River and we start hopefully repopulating other parts of the river," he said.
Maryland is home to at least 17 species of freshwater mussels, according to the Maryland Department of Natural Resources.
The department has documented one non-native invasive mussel species.
But the native population near Washington has been badly decimated by pollution in the past half-century and is in need of restoration, according to Naujoks.
Biologists in several southeastern US states have been deeply concerned by mysterious die-offs of species in that region's rivers.