Approximately one million fish killed near Broken Hill due to extreme weather conditions

One million fish are estimated to have been killed in New South Wales partially because of the heatwave situations sweeping throughout the nation.

The Department of Primary Industries (DPI) confirmed the fish discovered useless in Menindee Main Weir close to Broken Hill have been killed attributable to “low oxygen levels especially during extreme conditions such as increased temperatures”.

Broken Hill reached 38 levels on Thursday, its highest March temperature since 2019.

Locals believe 0ne million fish may have been killed at Menindee Weir near Broken Hill. — Locals consider a million fish might have been killed at Menindee Weir close to Broken Hill. (Supplied)

The species of fish killed was predominantly Bony Herring, in addition to smaller numbers of different large-bodied species reminiscent of Murray Cod, Golden Perch, Silver Perch and Carp.

Video emerged yesterday of the useless fish floating on high of an unlimited space of water at Menindee Weir pool close to Broken Hill.

There have additionally been studies of mass fish deaths within the Macquarie Valley this week.

The Bony Herring species will be “more susceptible to environmental stresses”.

“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,” DPI mentioned in an announcement.

“These fish deaths are related to low oxygen levels in the water (hypoxia) as flood waters recede.

“Significant volumes of fish together with Carp and Bony Herring, vitamins and natural matter from the floodplain are being concentrated again into the river channel.

“The current hot weather in the region is also exacerbating hypoxia, as warmer water holds less oxygen than cold water, and fish have higher oxygen needs at warmer temperatures.”

The division mentioned it was regular for the Bony Herring species to “boom and bust”.

“It ‘booms’ in population numbers during flood times and can then experience significant mortalities or ‘busts’ when flows return to more normal levels.”

Large numbers of dead fish have been reported in the Macquarie Valley this week. Source: NSW Irrigators' Council — Large numbers of useless fish have been reported within the Macquarie Valley this week. Source: NSW Irrigators’ Council (NSW Irrigators’ Council)

The occasion is much like one which occurred within the area in 2019.

Weatherzone mentioned in contrast to the 2019 occasion which was attributable to an algal bloom throughout drought, these deaths have been partly attributable to floods.

“This week’s deaths appear to have been a result of decomposing organic material brought into the river system by floodwater draining from Darling River’s floodplains,” Weatherzone mentioned.

“One thing both mass fish kill events have in common is that they starved the water of oxygen that fish and other organisms need to stay alive.

“The growing threat of mass fish deaths was highlighted in a Murray-Darling Basin water high quality and dissolved oxygen report issued by the NSW Government on March 15.

“High temperatures across western NSW in recent days have been exacerbating the situation, with warm water unable to hold as much oxygen as cooler water.”

The division mentioned companies throughout NSW and Commonwealth have been persevering with to work collectively on the response.

Anyone can report fish kills on 1800 043 536.