“There are dead fish everywhere,” Graeme McCrabb, a Menindee resident, said Sunday, describing the smell in the Darling-Baaka River in New South Wales as powerful and acrid. Among the dead fish are native species such as bream, Murray cod, golden perch, yellowtail and carp, he said.
Video he took from his boat showed a thick carpet of silvery fish carcasses lying in the water.
Australian officials have been aware of the disaster since Friday, acknowledging “an ongoing large-scale fish kill event” involving millions of carcasses in the river. The NSW Department of Primary Industries (DPI) blamed low oxygen levels in the water, known as hypoxia, as flooding recedes.
“The current hot weather in the region is also exacerbating hypoxia, as warmer water contains less oxygen than cold water and fish have higher oxygen needs at warmer temperatures,” the agency said in a statement Friday. statement.
McCrabb said the same remote area had it recorded large-scale fish kills in December 2018 and January 2019, calling them a result of poor quality water entering the river, which is often used for fishing. But this time, McCrabb said, the disaster is much worse, and many in the city are “angry and disappointed” that officials appear to have failed to learn from previous mass fish kills.
“No one was prepared for what was seen here,” McCrabb said, adding that officials “failed in their duties” to manage the river and collect data to help prevent such disasters.
“If you know the water quality is good or bad, you can make more informed decisions about how water is released downstream from lakes and avoid sending raw sewage downstream to kill fish,” McCrabb said.
sewage events they happen “during flooding, when organic material is washed from the riverbank and floodplain into the river system,” according to the New South Wales water department.
The government said the dead fish were predominantly bony herring, a species that experiences ups and downs in numbers.
“Its population increases during times of flooding and can then experience significant mortalities or ‘drops’ when flows return to more normal levels.” DPI fishing saying. “They may also be more susceptible to environmental stress such as low oxygen levels, especially during extreme conditions such as the increased temperatures currently being experienced in the area.”
Cameron Lay, director of freshwater environments at DPI Fisheries, described the situation as “very dire” and warned that 100+ degree temperatures in the area could bring further challenges.
“That in itself can present an ongoing risk to water quality and native fish, so we will do our best to monitor the situation and use whatever management options are available to us.” he said, according to the Australian Broadcasting Corp.
Acceleration of climate change is warming the waters and cooking creatures in their own habitats, the experts say. Many species are suffocating because warmer water can’t hold as much dissolved oxygen.
A study published last year found that if greenhouse gas emissions continue to rise, roughly a third of all marine animals could be gone within 300 years.
The remote location of the recent fish kills, in the far west of the state of New South Wales, is only making the disaster worse. The decomposing layer of fish has been visible for at least three days. “It’s hard to get people here in a hurry,” McCrabb said. “If you try to pick (the fish), you will probably break them and leave a fish soup. There really aren’t many answers.”
Multiple agencies are working on a response to the disaster, the New South Wales Department of Public Information said.
The New South Wales Department of Planning and Environment’s water division acknowledged “a large number of fish kills” and saying “Dissolved oxygen levels remain a concern for fish health.”
“The reality is that the Darling River is very sick. Years of mismanagement by the NSW government have exacerbated the impact of our changing climate,” Rose Jackson, Opposition Member of the NSW Parliament and Shadow Minister for Water and Housing, wrote on Twitter. The ecosystem “has been pushed to the breaking point.”
On Sunday, McCrabb said fish were still dying in the water, adding to the already monumental loss of aquatic life. “We started to lose more this afternoon,” he said, noting that some of the dead mass was beginning to move downstream.
He said more deaths along the river are likely in the coming days: “We’re in a world of pain here.”
Sarah Kaplan contributed to this report.