Hundreds of thousands of fish dead after NSW floods

Scientists find fish that could normally tolerate low oxygen levels among those killed in Richmond river

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Hundreds of thousands of fish have died after recent flooding in northern New South Wales caused severe deoxygenation" of rivers, with researchers alarmed at discovering carcasses of species that traditionally tolerate lower oxygen levels.

Scientists are still researching the full of extent of the destruction to marine life along the Richmond river, where multiple fish kill events occurred following flooding in late February and early March. The flooding led to a total lack of oxygen in a 60km stretch of the waterway, between Coraki and Ballina on the northern NSW coast.