Gymnocephalus cernuus


Photo credit: ©John D. Lyons
Gymnocephalus cernuus
  • The ruffe lives in freshwater ecosystems.

  • This is a small species of fish generally reaching only up to 20 cm in length. It is brownish in colour with dark spots over its body. Ruffe have a large spiny dorsal fin which is fused.
  • Download N.I.E.A. ID guide

Origin and Distribution:
  • Native to Europe and Asia. This species has become invasive in parts of continental Europe, Britain and also the Great Lakes in North America

  • The rapid growth and reproduction rate of this species impacts on fish communities as food and resources for native and desirable fish species become reduced.
  • Fish eggs are also a target food source for this species

How might it get here?
  • Introductions of this species are generally accidental or unintentional. This species can be introduced as live bait or in ballast water

Is it found in Ireland or Northern Ireland?
  • Not present in Ireland or Northern Ireland.

Prevent Spread:
  • Do not introduce non-native fish species.
  • Do not move species of fish from one waterbody to another.
  • Do not use live bait.
  • Report all sightings.

You can help by reporting any sightings:
Contacts/further information  

Species Related Files:

Invasive Species Ireland

Invasive Species Ireland