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Invasive Species: Eurasian Ruffe
*Established in Michigan*
Report this species:
Use the Midwest Invasive Species Information Network (MISIN) online reporting tool.
- Or - download the MISIN smartphone app and report from your phone - MISIN.MSU.edu/tools/apps/#home.
- Olive-brown back side and yellow-white belly.
- Fused dorsal fins with no notch, dark spots on membranes between the rays of the fin.
- About 25 cm. in length.
- Small, downturned mouth.
Illustration by Joseph R. Tomelleri
Photo courtesy of Gary Cholwek, U.S. Geological Survey. Bugwood.org.
Habitat: Ruffe are bottom dwelling fish that inhabit fresh and brackish waters. They appear to do well in a variety of habitat types, but abundance appears to be correlated with eutrophication and nutrient inputs.
Diet: Diet consists of mainly aquatic insects, but Eurasian ruffe will occasionally consume the eggs of other fish. A well-developed sensory system allows this species to feed at night. They have a few natural predators and the ability to hunt at night further reduces the risk of predation.
Native Range: Northern Europe and Asia.
Local Concern: The reduced risk of predation from hunting at night and having few natural predators in the United States makes them successful invaders.
Means of Introduction: Most likely ballast water from transoceanic vessels.
Other Common Names: ruffe, river ruffe, pope.
Native look-alikes and how you can tell them apart from Eurasian ruffe:
- Walleye: Dorsal fins separated, bottom of caudal fin has white tip, large mouth.
- Sauger: Dorsal fins separated, large mouth.
- Yellow perch: Dorsal fins separated, no distinct spots on dorsal fin, dark vertical stripes.
Status and Strategy for Eurasian Ruffe Management This document provides in-depth information about Eurasian Ruffe in the State of Michigan including identification, distribution, management, and control options.