Small native mammals disappearing from south-east Australia

28 November 2016

Four decades of research and monitoring of small native mammals in Victoria’s eastern Otway Ranges reveals ongoing declines in numbers, including some threatened species.

Researchers assessed 40 sites in the Otway Ranges from 2013 to 2016, using live-trapping and cameras. The sites revealed few or no native species present. Earlier research, conducted between 1975 and 2007, found four to nine native mammal species at study sites. The numbers of most species have declined significantly, while two threatened species, the marsupial swamp antechinus, Antechinus minimus and the native rodent the New Holland mouse, Pseudomys novaehollandiae, have plummeted.

The study is yet more evidence of the high rate of extinction of Australia’s distinctive land mammals. More than 10 per cent of Australia’s 273 native terrestrial species have become extinct over the past 200 years. A further 21 per cent of Australian endemic land mammal species are now threatened, suggesting that the nation will continue to lose one to two species per decade.

‘Conservation work is being hampered by lack of information. We need ongoing monitoring. With it, we might have picked up the decline in the Otway Ranges before it became so dramatic,’ said Dr Barbara Wilson, an Associate Professor in Ecology at Deakin University, Victoria, who has led the research.

‘Management actions that we need now include prevention of further fragmentation and degradation to habitats, appropriate controlled burning to protect key habitats, and control of predators. Effective monitoring will show us whether these management actions are successful and allow us to refine our approach,’ said Dr Wilson.

‘We are particularly interested in the swamp antechinus and the New Holland mouse because they have been listed as vulnerable under the federal Environment Protection and Biodiversity Conservation Act.’

‘We found native mammal populations declining in woodland, forests and estuaries. However, at coastal dune sites there were higher numbers, showing that these habitats can provide important refugia for mammals.’

Scientists say that the loss of Australian native animals is due primarily to introduced species, particularly foxes and feral cats.

Dr Wilson presented her results today at the Ecological Society of Australia’s 2016 annual conference in Fremantle, Western Australia. The Ecological Society of Australia is the peak group of ecologists in Australia, with over 1500 members from all states and territories. The Conference Program is available at: Twitter: #ESA16

For further information, including high quality images: Paul Holper, Scientell, 0407 394 661,