Videos posted to social media showed boats ploughing through a blanket of dead fish smothering the water in Australia, with the surface barely visible underneath.
"It's surreal to comprehend," he said, adding this year's fish kill appeared to be worse than previous ones. "The environmental impact is unfathomable." Populations of fish such as bony herring and carp had boomed in the river following recent floods, according to the state government, but were now dying off in huge numbers as floodwaters receded.
