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Leuciscus idus
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What is Ontario Doing?

To prevent this unwanted invader from coming into the province, Ontario has regulated Ide as prohibited under the Invasive Species Act, 2015. 


The Ide, or Orfe, is a freshwater, ray-finned fish in the carp family native to most of mainland Europe and Western Asia. It was imported into the U.S. in the late 1800s for aquaculture and has subsequently escaped into waterways throughout the eastern U.S. Ide generally prefers large bodied rivers, lakes, and ponds, and can tolerate brackish water.


The Ide has been recorded in nine states, including Maine, Connecticut, Pennsylvania, and New York, however the documentation of its distribution is poor. Importantly, there are currently no known records of the Ide in Canada.  

Impacts of Ide

  • Like other carp species, Ide threaten native fish populations by outcompeting native species for food and habitat. 
  • Ide is also capable of hybridizing with other cyprinids, such as Common Carp and Rudd.  
  • Ide has potential to spread new diseases and pathogens.  
  • Like most aquatic invasive species, once established, the Ide would be very difficult and costly to manage or eradicate.  

How to Identify

  • Thick, minnow-shaped body with dark grey back, silver sides, and small lateral-line scales.  
  • Fins are reddish-pink, except for the dorsal fin, while the mouth is small with a blunt snout. 
  • Can reach lengths of 102 cm (about 3.35 ft), but generally grow to 50 cm (about 1.64 ft) with a weight range of 0.5 – 1.5 kg (1 – 3.5 lbs.).   

What You Can Do

  • Learn how to identify the Ide and prevent the spread of this unwanted species. 
  • Do not release any live fish into Ontario’s lakes, rivers, or streams. Return or donate unwanted aquarium fish to a pet store or local school.  
  • Never buy or keep live Ide. 
  • If you’ve seen an Ide or another invasive species in the wild, please contact the toll-free Invading Species Hotline at 1-800-563-7711, visit EDDMapS, or search for the ‘Invasive Species in Ontario’ project on to report a sighting. 


    OFAH/OMNRF Invading Species Awareness Program. (2023). Ide. Retrieved from:
    This factsheet may be reproduced for non-commercial purposes.

    Header photo by mnauky | iNaturalist 

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