Professor Chris Dickman estimates that 480 million animals have been affected since bushfires in NSW started in September 2019. This statement explains how that figure was calculated.
Update 8 January 2020 : Professor Christopher Dickman revised his estimate of the number of animals killed in bushfires in NSW to more than 800 million animals, and more than one billion animals impacted nationally.
This figure is based on a 2007 report for the World Wide Fund for Nature (WWF) on the impacts of land clearing on Australian wildlife in New South Wales (NSW).
To calculate the impacts of land clearing on the State’s wildlife, the authors obtained estimates of mammal population density in NSW and then multiplied the density estimates by the areas of vegetation approved to be cleared.
Estimates of density were obtained from published studies of mammals in NSW and from studies carried out in other parts of Australia in similar habitats to those present in NSW.
The authors deliberately employed highly conservative estimates in making their calculations. The true mortality is likely to be substantially higher than those estimated.
Using that formula, co-author of the original report Professor Chris Dickman estimates that 480 million animals have been affected since the bushfires in NSW started in September 2019. This figure only relates to the state of NSW. Many of the affected animals are likely to have been killed directly by the fires, with others succumbing later due to the depletion of food and shelter resources and predation from introduced feral cats and red foxes.
The figure includes mammals, birds and reptiles and does not include insects, bats or frogs. The true loss of animal life is likely to be much higher than 480 million. NSW’s wildlife is seriously threatened and under increasing pressure from a range of threats, including land clearing, exotic pests and climate change.
Australia supports a rich and impressive diversity of mammals, with over 300 native species. The continent is uniquely dominated by marsupials and is the only great land mass to contain three major groups of living mammals: marsupials, monotremes (egg-laying platypus and echidna) and placentals. About 244 species, or 81 percent of this distinctive fauna, are found only in Australia.
Some 34 species and subspecies of native mammals have become extinct in Australia over the last 200 years, the highest rate of loss for any region in the world.
Professor Chris Dickman works in the School of Life and Environmental Sciences and has over 30 years of experience working on the ecology, conservation and management of Australian mammals.
Professor Dickman is a past President of the Australian Mammal Society and of the Royal Zoological Society of NSW, past Chair of the NSW Scientific Committee, and Chair of the Australian Marsupial and Monotreme Specialist Group for the Species Survival Commission of the IUCN. He is a Fellow of the Australian Academy of Science.
He has written or edited 16 books and monographs and authored a further 450 journals articles and book chapters.