Alongside a series of devastating images, the 53-year-old conservationist wrote: "The day in Australia when I saw 500 dead animals for every live one will remain with me forever. This is a call to arms and we are blessed with a celebrated army of passionate conservationists."
"I hope that this photograph of a lone koala I found sitting dumbfounded at the base of a tree, which we are calling 'Survivor,', becomes known and emblematic of a period in time when we all became aware of our planet's deep fragility - and that it can help us raise money to make a difference."
So far, the campaign has been endorsed by a number of famous faces with Chris Hemsworth, Cara Delevigne and Cindy Crawford pledging their support.
Earth Alliance, an organisation built by Leonardo DiCaprio in response to the growing climate crisis, has also endorsed the project.
The recent wildfires are the worst seen by the nation in decades with more than a billion animals thought to have perished so far - including up to 30% of the koala population living in New South Wales.
Those who make a donation of $1,000 or more will receive a signed print of 'Survivor' while those who donate between $10 and $100 will receive a downloadable file of the image.