Naugatuck River and roadways, through the time of development of Connecticut Route 8. The river enters a forested, hilly area between Connecticut Route 118 and Thomaston. The largely industrialized cities of the Naugatuck River Valley were developed on each side of the river, with periodic sections of forested areas, before it enters the Housatonic River at Derby, at about above sea level. As part of the Housatonic River watershed, the Naugatuck River historically hosted the southernmost Atlantic salmon ("Salmo salar") migrations. Historical runs of anadromous fish also included native American shad ("Alosa sapidissima", Connecticut's state fish), alewife ("Alosa pseudoharengus") and blueback herring
Assabet River followed by deliberate introduction into ponds near the Concord and Sudbury Rivers. This is now an invasive, habitat-destroying plant across many of the eastern states. On the Assabet River, OARS (Organization for the Assabet, Sudbury and Concord Rivers) organizes an annual plant pulling event in early July. Volunteers in canoes hand-pull the surface-floating rosettes of leaves and nuts before the nuts mature and fall to the bottom. Alewife, "Alosa pseudoharengus" is an anadromous species of herring found in North America, anadromous meaning that it mates and is born in fresh water, but live most of its life in saltwater. In