Found in the wet soil of Manchaug Pond is the Eastern Elliptio (Elliptio complanata complex), one of the most common freshwater mussel species in New England. These clams or mollusks can grow up to five inches in length and live for many years. The outside of its shell is tan in juveniles to dark brown or black in adults. The inside of the shell, called the nacre, is colored white, pink, or purple. It’s iridescent surface, commonly called “mother-of-pearl, made it attractive and commonly used to make “pearl” buttons before the invention of plastic ones in the 1940’s. It doesn’t seem to have a preference for fast or slow flowing water or any particular substrate (soil). Freshwater mussels are filter feeders doing the important job of filtering nutrients and sediments from the water. When present in high numbers, the mussels help keep the water clear and of high quality with their presence considered an indicator of a healthy lake.
Dead, empty shells are often found along the shore or on docks as the Elliptio is a common food of muskrats and raccoons, but the biggest danger to these bivalved filter feeders is from chemical pollution and silt that can enter lakes and streams from the watershed which clogs the mussel’s gills. Also a factor, is the timing and speed of our drawdown of the water level in the fall which must allow the adult mussel to migrate, moving through the mud by burrowing with its muscular foot.
Moss Animals or Bryozoans
Looking like small lobsters, these freshwater crustaceans are found near the shore living under submerged stones or walking along in shallow water.
Stem group: Pectinatella
Strange as it may seem, moss animals or bryozoans (Pectinatella magnifica) are aquatic organisms found in Manchaug Pond. They live in colonies forming a firm, gelatinous mass, typically less than a foot across, attaching themselves to submerged logs, twigs, stones and docks. Pectinatella magnifica, the magnificent bryozoan, is one of 19 species of freshwater bryozoans native to North America and found in calm and shady lakes and reservoirs. They are filter feeders.