The Sydenham River is a riverinChatham-Kent, Lambton County and Middlesex County in southwestern Ontario, Canada, flowing southwest from its source west of London, Ontario and emptying into Lake Saint Clair.[1] The length of the river is 165 kilometres (103 mi) and it drains a watershed of approximately 2,700 square kilometres (1,000 sq mi). The river flows through the towns of Strathroy and Wallaceburg. It was named after Lord Sydenham, governor of Canada from 1839 to 1841.
Unusual concretions, composed of calcite, can be found near this river. These are known as "kettles" because they resemble the bottom of a large kettle.
The river has been identified as a key biodiversity area.[2][3]
Because this river flows through a large agricultural area, its waters collect silt and fertilizer runoff. In spite of this, the river provides habitat for 80 fish species and 34 species of freshwater mussels; these include:
The Northern madtom (Noturus stigmosus), once found in the river, is considered to be "likely extirpated".[1]
In Canada, the Northern Madtom is known only from the Detroit River, St. Clair River, Lake St. Clair, the Thames River and the Sydenham River (Figure 3).
The report by the International Union for Conservation of Nature lists Canada's "freshwater key biodiversity areas" or KBAs. Of the four KBAs in Ontario, three are in the southwestern part of the province: eastern Lake St. Clair, the east Sydenham River, and the Ausable River.
The discovery of the new species could mean the existence of other unknown species in that part of the Sydenham, he said. In 2017, researchers identified 20 different species of mussels in the river.
42°35′13″N 82°13′29″W / 42.58683°N 82.22460°W / 42.58683; -82.22460
