Ornamental fish enthusiasts and backyard pond owners are reminded to help stop the spread of pest fish this season.

Fisheries Queensland biologist Danielle Stewart said Queensland's waterways were at risk of becoming overrun with introduced pest fish.

"Populations of pest fish have successfully established in many of Queensland's local waterways and are a major threat to the high diversity of native fish," she said.

"Ornamental fish enthusiasts and backyard pond owners can assist in helping us to stop the spread of pest fish into Queensland's waterways.

"Be sure to screen outdoor ponds to prevent escape and overflow during heavy rains.

"If you're spending your holidays away from home, and no longer want or can care for your fish, give them to friends or a pet shop instead of letting them go in the wild.

"If considering fish as a gift, choose native fish instead of exotics. Contact your local aquarium or Fisheries Queensland on 13 25 23 for information on local native fish species."

Ms Stewart said members of the public can also help by learning how to identify freshwater exotic from native fish and reporting sightings.

"An easy way to distinguish a pest fish from a native fish is by looking at the dorsal fin," she said.

"Pest fish usually have a continuous dorsal fin, while native fish usually have a dent or gap separating the front of the dorsal fin from the rear.

"If you catch or see a pest fish, please report it to Fisheries Queensland immediately.

"Be sure to provide as much information as possible including the location, date, type of waterbody, description of the fish and a photograph.

"Don't forget the photo-it's extremely important to help us quickly and accurately respond to a pest fish sighting," Ms Stewart said.

For further information on pest fish and to report possible sightings call Fisheries Queensland on 13 25 23 or visit www.fisheries.qld.gov.au

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