Hundreds of dead fish wash up along the Brisbane River

Reports of hundreds of dead fish littering the banks of the Brisbane River since Friday have prompted an investigation by state wildlife authorities.

An Environment Department spokeswoman said it had responded to reports of dead fish around St Lucia, Yeronga and Indooroopilly.

“Our officers have been deployed to inspect the areas where dead fish have been reported, and will collect water and fish samples for further analysis,” she said.

Dead fish on the Brisbane River at Guyatt Park ferry terminal in St Lucia.Credit: Catherine Strohfeldt

Residents reported additional sightings further upstream, extending past Chelmer as far as Seventeen Mile Rocks.

Chelmer resident Shelley Gunn said she and her husband noticed an “oil slick” in run-off from stormwater drains about 8am Thursday, which they reported to authorities.

Just some of the hundreds of dead fish seen along the Brisbane River.Credit: Environment Department

“[Friday] afternoon we then noticed heaps of ‘white things’ floating down the river but could not make out what it was,” she said.

“We then noticed the community post [from the Environment Department] and put two and two together.”

Theories about run-off or construction debris leading to toxic water conditions were raised online by concerned residents, while authorities said fish deaths could be caused by “a range of environmental factors”.

“A potential cause of [these] deaths may be the recent heavy rain, which has washed organic matter into the river, resulting in low dissolved oxygen levels,” the department spokeswoman said.

She added that the investigation was continuing, and urged anyone with relevant information, including further sightings of dead fish, to contact the department’s pollution hotline on 1300 130 372.

Brisbane City Council declined to comment on the matter.

Brisbane has recorded 140 millimetres of rain since last Sunday, with about half of that falling last weekend alone.

But the recent burst of wet weather is forecast to clear after Friday night’s downpour, in which 24 millimetres were recorded in Brisbane City.

However, experts have predicted wet weather conditions throughout summer in Queensland, including at least one cyclone touching down in January or February.

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