2014 Catchment Champion
Dr Andrew Norris
Senior Fisheries Biologist, Department of Agriculture, Fisheries and Forestry
Pest fish on the move in Queensland
Tilapia, one of the world’s most invasive fish species, is spreading rapidly throughout the State and Fisheries Queensland is urging the community to be vigilant in the fight to stop the spread.
These fish are regarded as one of the greatest threats to Australia’s aquatic ecosystem.
Two species of tilapia have infested Queensland waterways: the Mozambique Tilapia and the Spotted Tilapia. These two species are now distributed throughout many locations in Queensland and are threatening to invade new waterways.
It is almost impossible to eradicate a population of tilapia from a flowing river or creek. Therefore, the public needs to be aware of these pests and know what they can do to help stop them from spreading further.
The public could help control the spread of tilapia by knowing how to identify them, avoiding any actions that could result in them being moved between waterways and reporting them.
It is illegal to use tilapia as live or dead bait and if anyone catches a tilapia, they must kill it humanely and bury it instead of returning it to the water.
People should also make sure they stock dams or ponds with native fish, as it is illegal to stock tilapia. Penalties of up to $200,000 apply for people found with tilapia in their possession.
How to identify tilapia
- An easy way to distinguish tilapia from most native fish is by looking at their dorsal (upper) fin. Tilapia have a continuous dorsal fin that ends in an extended point, while most natives have a dorsal fin with a dent in the middle and a rounded end.
- Their pelvic (belly) fins are also very long and almost touch the front of the anal (bottom) fin. Most native fish have short pelvic fins.
- Mozambique Tilapia can vary in colour from dark grey to light silver, while Spotted Tilapia have more of an olive colour to them. Both species can have dark blotches on their sides.
- Mozambique Tilapia have a pronounced jaw and mature males can also have red edgings on their fins.
What can you do to help?
When reporting a sighting you should provide information such as date and location of sighting, description of fish, a photo (if possible) and a brief description of the waterway.
Fisheries Queensland uses public reports of sightings to respond to any new tilapia infestations quickly before breeding populations establish.
For more information or to report a pest fish sighting phone 13 25 23 or visit www.fisheries.qld.gov.au
Tilapia factsheet (662 KB)