A Few Newcomers in the Rideau River
Flowering rush (Butomus umbellatus) is a tall shoreline plant with pink flowers. Native to Europe and Asia, it was first discovered in Canada along the St. Lawrence River in 1897. Flowering rush has since spread throughout northern U.S. and southern Canada.
This exotic species appears to be better adapted to flowing water than most native emergent species because it can grow in deeper and faster-moving water. This species is definitely spreading and is a problem along the length of the Rideau River shoreline because it crowds out native species. [3, 4, 5, 6]
By 1952 this plant had spread to the Ottawa River. By 1982 it had spread to the Great Lakes. Since its introduction in Ottawa, European frogbit has become one of the dominant plants in many eastern-Ontario wetlands, and has reduced native plant biodiversity.
Eurasian water milfoil
Eurasian water milfoil is spread by aquatic birds and boat traffic (on propellers), which transport fragments of the plants to new areas. Fragments are able to root and grow.
In many eastern Ontario rivers, Eurasian water milfoil has displaced native aquatic plant species. Eurasian water milfoil has been found along the length of the Rideau River. Fortunately, this exotic does not seem to be harming other plants or animals along the Rideau River. [3, 4, 5, 6]
|Last Update: 2007-05-18|
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