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
Atlantic herring not considered to be an Arctic species. The small-sized herring in the inner parts of the Baltic Sea, which is also less fatty than the true Atlantic herring, is considered a distinct subspecies ("Clupea harengus membras") ("Baltic herring"), despite the lack of a distinctive genome. The Baltic herring has a specific name in many local languages (Swedish "strömming", Finnish "silakka", Estonian "räim", "silk", Livonian "siļk", Russian "салака", Polish "śledź bałtycki, sałaka", Latvian "reņģes", Lithuanian "strimelė") and is popularly and in cuisine considered distinct from herring. For example, the Swedish dish surströmming is made from Baltic herring. Herrings reach sexual maturity