Eurasian Ruffe is a sharply spined fish native to northern Europe and Asia. A member of the perch family, it was likely introduced to North America through the dumping of ballast water by ships from Europe. It was first observed in western Lake Superior in 1986 and has since spread.
Eurasian Ruffes mature quickly in 2 to 3 years, have rapid reproductive and growth rates and adapt quickly to new environments. They have a lifespan of about 7 years. They prefer turbid lakes with soft bottoms and little or no vegetation and rivers with slow moving current.
Eurasian Ruffes are usually smaller than 20 cm long, but they have sharp spines on their gill covers and fins which discourage predators.
Eurasian Ruffe have been recorded in the Kaministiquia River near Thunder Bay as well as more recently in the St. Lawrence River east of Kingston. It is also found in the United States in numerous rivers and bays along the southern shore of Lake Superior and in Lake Huron and Lake Michigan.
Gymnocephalus cernua Adult(s) – Photo by Gary Cholwek
Eurasian ruffe Gymnocephalus cernua Adult(s) – Photo by Doug Jensen
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