As bushfires rip across parts of Australia, experts are warning of an immense loss in biodiversity and threat to the lives of millions of animals.

One estimate is that in the state of New South Wales alone, nearly half a billion animals have been affected by the fires.

John Marsh works at the Potoroo Palace nature sanctuary in the fire-hit Merimbula, New South Wales. He explains how even after the fires pass, surviving animals will face an uncertain future.