Hundreds of Thousands of Fish Killed in Australian River Basin

The Darling River provides a home to endangered fish species, as well as supplies water to farmers and metropolitan areas. (Wikimedia Commons)

Up to one million fish have been found dead in a mass fish kill along the Darling River in Australia’s southeastern state of New South Wales (NSW). According to the Murray-Darling Basin Authority, the impacted species include the critically endangered Murray Cod, some of which were up to 100-years-old. The Darling River also serves as an important breeding ground for several other endangered fish species, including the golden perch.

The fish kill occurred in January, during Australia’s summer months, as the latest in a series of fish kills in the same region. The New South Wales Department of Primary Industries, which oversees the development of agriculture, fisheries, and biosecurity, attributed the environmental disaster to “several related and compounding factors resulting in low oxygen in the river.”

More specifically, the report suggests that a rapid temperature drop from 48°C to 28°C (118°F to 82°F) resulted “in conditions conducive to blue-green algal blooms.” That, in combination with an ongoing drought, “reduced dissolved oxygen available to fish.”

The fish kill came to national attention by way of a viral video posted to Facebook of two Menindee residents holding up fish from the latest incident. In the video, Dick Arnold and Rob McBride claim that the incident “is nothing to do with drought; this is a manmade disaster.”

Arnold and McBride are among a number of locals and politicians who allege that the most recent fish deaths result from corruption and greed, and accuse the state government and cotton growers of mismanagement of the Murray-Darling basin.

Farmers have also raised concerns over the impact of the environmental disaster on their businesses. At potential risk for water poisoning include 250,000 livestock, in addition to millions of native fish without access to an alternate water supply. The Land writes that metropolitan areas such as Broken Hill that use the Darling River and Menindee lakes as water sources may also be adversely affected.

According to critics, the origins of the crisis lie in the government turning a blind eye to cotton growers in the region siphoning water for irrigation purposes from the lakes that feed into the river. The Guardian reports that in March 2018, the state ombudsman criticized regulator WaterNSW, the state-owned corporation in charge of running water infrastructure and ensuring compliance with Murray-Darling’s water laws, for not taking any enforcement actions and prosecutions against water theft for a period of 15 months, despite WaterNSW’s quantitative reports claiming such enforcement actions were taking place.

Moreover, the New South Wales government changed water-sharing laws in 2012 by increasing allowances on irrigators’ pump sizes, removing daily extraction limits, and allowing for more storage.

Under the current system, the total allotment legally drawn from the river per year amounts to 11,000 gigalitres—the rough equivalent of 5.5 million Olympic swimming pools—according to Discover Murray, a nonprofit organization whose mission is to promote the Murray River and surrounding region. However, this figure does not account for additional water theft, which the state ombudsman accused the New South Wales government of ignoring. Discover Murray estimates the full amount of water in the Murray Darling to be no more than 30,000 gigalitres.

Sky News reported that Jeremy Buckingham, a former Greens and current independent member of the New South Wales legislative council, said that “the huge extraction of water for big irrigators is literally choking the life out of the system downriver and leaving stagnant, blue-green algae infested dregs for everyone else.”

Buckingham further emphasized the severity of the situation, telling the Sydney Morning Herald, “It is an ecological catastrophe on an international scale.”