Invasive species and habitat loss our biggest biodiversity threats


A desire to avoid more extinctions is one of the drivers behind new research by the Threatened Species Recovery Hub which has identified invasive species as the no. 1 threat to Australian biodiversity with habitat loss a close second.

Lead Researcher Stephen Kearney from the University of Queensland said Australia was rich in unique biodiversity but has had a poor track record since European settlement.

“We are one of only 17 ‘megadiverse’ countries globally, Australia contains over 12% of the world vertebrate species. Over 4 out of 5 of our species are found nowhere else on earth,” said Mr Kearney

“Australia has also recorded 90 extinctions since European settlement, 36 plants, 27 mammals, 22 birds, four frogs and an earthworm, and extinction rates per decade are not improving

“One of the major causes of Australia on-going extinction crisis is our insufficient response to threats to our biodiversity.

“To support improvements in this area we have reviewed the major threats facing over 1500 species listed as Critically Endangered, Endangered or Vulnerable under Australian environmental law.

“The top factors impacting Australia threatened species are invasive species which affect 82% of our threatened species and changes in habitat which affect 74% of species.

“Invasive species include pest animals, plants and diseases. While changes to habitat include things like altered fire patterns and degradation from human activities.

“Around the world the top two impacts on threatened species are habitat loss and change due to agriculture, closely followed by over exploitation activities, such as hunting or timber harvesting.

“Over exploitation threatens around three quarters of imperilled species globally, but only about one quarter of Australian species.

“The large impact of invasive species sets Australia apart from the global trend.

“Globally, invasive species only impact around a third of threatened species, but in Australia they are a threat to 100% of threatened frogs, over 95% of threatened mammals, fish and birds, and to about 80% of threatened
plants, insects and reptiles.”

Chief Executive of the Centre for Invasive Species Solutions, Andreas Glanznig, said invasive species have pushed native species to a crisis point and without innovation and new game changing management options we will see an ongoing-downward spiral.

“Australia is in the midst of an extinction crisis and invasive species don’t stop at state borders, so we need to continue to take landscape-scale and coordinated action against invasive species.

“It’s now an arms race and we need new and innovative ideas, such as biocontrol agents and genetic technologies, so we see invasive species decline and threatened species rise,” Mr Glanznig said.

Stephen Kearney concludes, “The variety of threats facing Australian species highlights the need for a comprehensive approach to manage their impacts, including adequate resourcing, legislative support and better national co-ordination.”

The Threatened Species Recovery Hub is a collaboration of 10 leading Australian universities and the Australian Wildlife Conservancy to undertake research to support the recovery of Australia’s threatened species.
The Centre for Invasive Species Solutions is one of the world’s largest collaborative pest animal and weed research and development initiatives. It is a 17-partner collaboration between government, industry and research organisations to tackle invasive species issues at a national scale.

Main Threats Aust and Global_Credit Threatened Species Recovery Hub (1)

GRAPH: Major threats to threatened species in Australia (black bars) and globally (grey bars). Threats are defined by International Union for the Conservation of Nature (IUCN) categories. Credit: Threatened Species Recovery Hub