The Quashnet River, also known as Quoshnet River or Moonakis River, is a 5.1 miles (8.2 km) estuary

Estuary

An estuary is a partly enclosed coastal body of water with one or more rivers or streams flowing into it, and with a free connection to the open sea....

 in Falmouth, Massachusetts

Falmouth, Massachusetts

Falmouth is a town in Barnstable County, Massachusetts, United States; Barnstable County is coextensive with Cape Cod. The population was 31,531 at the 2010 census....

 on Cape Cod

Cape Cod

Cape Cod, often referred to locally as simply the Cape, is a cape in the easternmost portion of the state of Massachusetts, in the Northeastern United States...

. Its area is about 1 square miles (2.6 km²).

The river is connected by ditch to John's Pond in Mashpee

Mashpee, Massachusetts

Mashpee is a town in Barnstable County, Massachusetts, United States. The population was 14,006 as of 2010.For geographic and demographic information on specific parts of the town of Mashpee, please see the articles on Mashpee Neck, Monomoscoy Island, New Seabury, Popponesset, Popponesset Island,...

, just north of today's Route 28. It is fed by groundwater and flows south, gaining water as it goes, into Waquoit Bay

Waquoit Bay

Waquoit Bay is a small landlocked tidal bay on the south shore of Cape Cod in the US state of Massachusetts. The bay is connected with Nantucket Sound and separates the towns of Mashpee and Falmouth.In the early 1960s Norwegian researcher Johannes Kr...

 which then flows into Nantucket Sound. During colonial times it was known for its abundant brook trout

Brook trout

The brook trout, Salvelinus fontinalis, is a species of fish in the salmon family of order Salmoniformes. In many parts of its range, it is known as the speckled trout or squaretail. A potamodromous population in Lake Superior are known as coaster trout or, simply, as coasters...

 but was dammed in the mid-19th century for water power. After the mills burned and the dam was breached, the valley was converted to cranberry

Cranberry

Cranberries are a group of evergreen dwarf shrubs or trailing vines in the subgenus Oxycoccus of the genus Vaccinium. In some methods of classification, Oxycoccus is regarded as a genus in its own right...

 cultivation in the early 20th century. Cranberry production stopped in the 1950s, and the cranberry bogs were abandoned. The land was purchased by the Commonwealth of Massachusetts beginning in the late 1950s, and Trout Unlimited

Trout Unlimited

Trout Unlimited is an international non-profit organization dedicated to the conservation of freshwater streams, rivers, and associated upland habitats for trout, salmon, other aquatic species, and people. Often contracted as "TU," the organization began in 1959 in Michigan...

 and other organizations began to restore the river to trout

Trout

Trout is the name for a number of species of freshwater and saltwater fish belonging to the Salmoninae subfamily of the family Salmonidae. Salmon belong to the same family as trout. Most salmon species spend almost all their lives in salt water...

-quality in the 1970s.

Today the river is an important migratory fish run for alewife

Alewife

The alewife is a species of herring. There are anadromous and landlocked forms. The landlocked form is also called a sawbelly or mooneye...

 and salter brook trout, home to herring

Herring

Herring is an oily fish of the genus Clupea, found in the shallow, temperate waters of the North Pacific and the North Atlantic oceans, including the Baltic Sea. Three species of Clupea are recognized. The main taxa, the Atlantic herring and the Pacific herring may each be divided into subspecies...

 and eel

Eel

Eels are an order of fish, which consists of four suborders, 20 families, 111 genera and approximately 800 species. Most eels are predators...

s, and is Waquoit Bay's largest source of fresh water. Additional portions of its watershed were purchased through the years by various entities. The area is now a wildlife management and conservation preserve managed by the Waquoit Bay National Estuarine Research Reserve.