Alarm over Mary River fish threat
MARY River conservationists are angry at the involvement of the misguided fishing enthusiasts who have helped spread one of Australia's worst pest fish into the Borumba Dam and Mary River system.
Mary River Catchment Co-ordinating Committee officer Dale Watson said the fish, Tilapia, had been rightly dubbed "the cane toad of our waterways."
He said the fish, introduced from east Africa, was the kind of creature you would only want in a river system if you did not want any other kind of fish there at all.
"They are mouth breeders, which shelter their young and that means many more of them reach maturity than is the case with most native fish.
"They are also very aggressive and kill off competing native species," he said.
The fish was recently discovered in Yabba Creek and there was concern at the imminent danger it would pose to the Mary River system and its unique fish species, he said.
Also known as the Mozambique mouth-brooder, he said it could quickly dominate a water body, out competing native fish for habitat and food.
"Its feeding and nesting habits degrade water quality.
"Once established in a flowing river or creek, Tilapia are almost impossible to eradicate," he said.
The continuous long dorsal fin is a key identification characteristic.
The fish is declared noxious in Queensland.
"It is unlawful to possess noxious fish alive or dead or to use them as bait.
"Penalties up to $200,000 apply," he said.
"If you catch a Tilapia, do not release it; kill it humanely and dispose of it away from the water body," he said.
"We are urging everyone to be on the lookout for these pests, especially if they are fishing or enjoying the waters of Borumba Dam and Yabba Creek."
Tilapia are deep bodies with a thin profile and long pointed fins.
The fish are usually dark grey but can be silver, with two to five dark blotches or spots on their sides, Mr Watson said.
Any sightings or catches of the pest fish should be reported to the MRCCC on 5482 4766 or the 24-hour Fishwatch hotline on 1800 017 166.