A video showing the shocking sight of millions of dead fish clogging an Australian river has been released as a heatwave sweeps the region. The footage, taken at the Darling River in the Menindee region of New South Wales, shows the devastating impact on the environment from decreased water levels and high temperatures. The river has been affected by low water levels due to water extraction for intensive farming, causing a lack of oxygen for the fish. The heatwave, which has seen temperatures soar to over 40C in some areas, has only exacerbated the situation. Local authorities are now calling for urgent action to save the river and its wildlife.