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American Eel

American Eel
   Photo: Duane Raver/U.S. Fish & Wildlife Service

Features: The American Eel (Anguilla rostrata) is a brownish, elongated fish normally growing up to 1 metre in length and weighing up to 1.5 kg, with a single continuous dorsal fin that joins the caudal and anal fins. They have a thick skin that can secrete large amounts of a protective slimy mucous. This species spawns in the Sargasso Sea, in the North Atlantic Ocean near Bermuda. After hatching, young eels migrate towards North America and enter freshwater systems where they mature. Once mature, 10 to 25 years later, they migrate back to the Sargasso sea to spawn and recommence the cycle. Historically, the American Eel was of major economic importance, but over recent decades their numbers have declined dramatically.

Status: Endangered Provincially, Special Concern Nationally

Range: The American Eel is widely distributed in freshwaters, estuaries and coastal marine waters along the east coast of North America from Greenland and Iceland to northern South America. In Ontario, it occurs mainly along the St. Lawrence River and Lake Ontario and their tributaries. Historically, it was present throughout the Ottawa River drainage system. Since construction of the Welland Canal, eels have been occasionally observed in the Great Lakes upstream of Lake Ontario (as far north as Thunder Bay Harbour), but these areas are not considered to have been part of their historic range.

Threats: American Eel appear to be in decline throughout their global range, and in Ontario this decline has been precipitous (about 90%). Threats to American Eel include: overfishing; mortality by hydroelectric turbines during downstream migration; hydro dams that inhibit upstream migration; and habitat loss/degradation. Changes to the ocean currents that aid the distribution of larval eel may also have had an influence on their abundance in the northern portion of their range.

Protection: The American Eel is listed in regulation under Ontario's Endangered Species Act, 2007, which protects the species from being killed or harmed. In 2004, the government of Ontario developed a management program that banned the harvest of American Eel in the province. An action plan to restore eels in the St. Lawrence River/Lake Ontario region, and a management plan that covers all of the eelīs range in Canada, are being developed. As well, eel ladders for passage at hydroelectric dams have been constructed at dams in the St. Lawrence River. Finally, eel have also been stocked in the St. Lawrence River.

Text Sources: Tremblay et al. 2006

Last Modified Date: October 2008

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