There is a concerning discovery of thousands of dead and dying fish on riverbanks following the impact of Cyclone Alfred on marine life.
After Cyclone Alfred hit Australia’s northeast region, a significant number of fish are being found dead or dying along the Richmond River at Ballina in northern New South Wales (NSW), as reported by charity OzFish.
The public is being urged to assist in monitoring the fish kill in the area heavily affected by the cyclone, which caused widespread flooding in the region and southeast Queensland a week ago.
Local residents have been cautioned to expect more fish kills, and the NSW government fisheries spokesperson has confirmed an investigation is underway.
According to the spokesperson, “Fisheries staff are working with local councils to monitor water quality and fish deaths, with several areas being impacted. Continued fish kills in this region are anticipated in the coming days and weeks.”
OzFish is requesting locals to report any dead fish they come across to assess the scale of the situation.
Cassie Price, the CEO of OzFish, believes that the cause of the fish deaths is likely due to black water with very low oxygen levels. When organic matter like dirt and leaf mold enters waterways, it can lead to water turning dark and depriving it of oxygen as it decomposes.
Courtesy of OzFish
Photos provided by the charity show fish stranded on the riverbank, with reports of mud crabs and eels trying to escape the contaminated water.
Price mentioned that water tests conducted by volunteers have shown concerning results. She stated, “Good water should have a minimum of 5 milligrams (mg) of oxygen per liter. Fish become distressed below 4 mg per liter and start dying at 2 mg. In the Richmond River today, dissolved oxygen levels are nearly non-existent, at 0.4 mg.”
Individuals can support OzFish by sharing their location, estimating the number of fish, identifying key species, and providing photos and videos of the situation.
Although numerous fish kills are reported in NSW each year, some incidents are more catastrophic than others.
For example, the flooding of the Darling River at Menindee in March 2023 resulted in an estimated 20 million fish deaths. Additionally, earlier this year, a marine heatwave was believed to have caused approximately 30,000 dead fish at Gnoorea Beach near Karratha on Western Australia’s Pilbara coast.
Price emphasized the importance of restoring swamplands around the Richmond River to prevent similar events in the future.
“Immediate action is necessary to prevent further fish kills and enhance the resilience of our waterways,” she stated.
AAP contributed to this story.
