A Narrandera Inland Fisheries Centre team is on site at what is the worst ever mass fish kill to hit the Darling River at Menindee.
A constant stream of mostly bony bream has been floating down the river since last Friday morning, as well as golden perch and silver perch and some Murray cod.
Authorities have confirmed the overall scale and size of this mass fish kill eclipses similar events in 2018 and 2019.
The horrific incident has been caused by low oxygen levels in the water combined with high temperatures.
The NSW Department of Primary Industries (DPI) said it would continue to assess the risks to fish health in the area through ongoing monitoring.
“This event is ongoing as a heatwave across western NSW continues to put further stress on a system that has experienced extreme conditions from wide-scale flooding,” it said in a statement.
“The amount of dissolved oxygen water can hold decreases with increasing water temperature, which can add additional stress to fish that may already be struggling. The low oxygen levels occurred after recent flood waters receded, dragging dirt and muck and bacteria back into the river that is already over-populated with carp.”
The DPI said the bony bream species normally experienced a “boom-bust” population cycle, especially when there was immense flooding, but never on the scale seen right now.
During the state’s devastating drought in 2019, millions of dead fish were found in the area, putting the management of the Murray-Darling Basin under the microscope.
A WaterNSW spokesperson said it had increased monitoring the Menindee Lakes area in recent months to track the impact of prolonged flooding in the region.
A 40-kilometre algal bloom blamed for the death of one million fish in 2019.
The 2019 event coincided with a period of high temperatures in the state’s far south and drought along the river system.
Last year thousands of fish were found dead at Menindee lakes and in 2019 the tragic Menindee Fish Kill event saw one million fish die on the Barka/Darling River.
Narrandera Fisheries Centre was responsible for the rescue and care of the surviving native fish, including the breeding of over 60,000 new fish to be returned to the Barka/Darling River.
During 2020, the Cad Factory and the Clontarf Academy worked with the Fisheries Centre to understand and share the connections between the two different river systems and how they could can come together to understand through a sharing of arts, science and ancient knowledges.
The Academy participated in breeding and caring for the fingerlings before travelling to Menindee to hand them back to Barkindji Aunties and River Rangers.
Twenty surviving Murray Cod from the Barka River had been brought to the Narrandera Fisheries Centre (Department of Primary Industries) to heal and breed in 2020.
Over October, November and December 2020, Narrandera’s Clontarf Academy participants worked with Matt McLellan from the Narrandera Fisheries Centre.
Every week the students tended to the fish and helped prepare them for being released back on Country.
Before the ‘official’ release of 60,000 Cod they travelled to Menindee and worked with local Barkindji Elders, Aunty Patsy Quayle, Aunty Cheryl Blore, Aunty Barbara Quayle, plus local river rangers, to undertake a cultural release of 200 Cod.
Scientist Matthew McLellan from the Narrandera Fisheries Centre recently joined Barkindji River Rangers Cheryl Blore and Barbara Quayle, First Nation Educators Wiradjuri men Neville Bamblett and John Ingram, to share details of the project at the recent World Fishing Conference in Melbourne during late February at the Melbourne Conference and Exhibition Centre.
It is the world’s most prominent gathering of the recreational fishing community and is held every three years with the aim of providing a unique learning opportunity as well as a chance to showcase Australia’s fishing and tourism experiences to leading and influential recreational fishing stakeholders from across the world.
This article appeared in the Narrandera Argus, 23 March 2023.
