Australia has experienced a bizarre environmental disaster in recent weeks as more than a million fish have died in an inland river, prompting debate about whether too much water is being extracted by farmers.

Two main instances of mass deaths have occurred - in December and earlier this month - in the lower Darling River, which forms part of the nation's food bowl. The incidents occurred near Menindee, a small outback town in western New South Wales. Other smaller outbreaks have also occurred.