Freshwater pest identification cards

Many ornamental aquarium fish are non-native species, i.e. fish that are not found naturally in the Northern Territory. They can become pests if they are released into freshwater lakes, billabongs, creeks and rivers.

If released into our waterways, non-native fish can:

  • compete with native fish for food and space
  • dominate waterways by reproducing in large numbers, hybridising with native species and surviving in adverse and disturbed habitats
  • alter and disturb natural habitats
  • feed on native fish, insects and plants
  • introduce diseases and parasite.

The Department of Primary Industry and Resources has developed a new educational tool Freshwater Pest Identification Guide PDF (7.5 MB) which outlines:

  • the problems non-native fish can cause
  • identification of non-native fish
  • how you can help if you think you have spotted a pest.

Download the Freshwater Pest Identification Guide PDF (7.5 MB) and keep an eye out for unusual fish and aquatic plants to help protect our waterways.

For further information, email

You can also download the NT Fishing Mate app for free!

Last updated: 30 July 2020

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