Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Alien predators are more dangerous than native predators

Introduced predators such as foxes and cats are twice as deadly as native predators to Australia’s unique native animals, a new study has found.

The new finding, published this week in the prestigious journal Proceedings of the Royal Society B, is the first confirmation of what has been a long-held hypothesis among scientists.

It also highlights the heavy continuing impact of these predators long after their introduction and that Australia's fauna has been among the hardest hit in the world.

Experts believe that introduced "alien" predators are more dangerous than native predators because their prey, such as numbats and bettongs, are naïve to the hunting tactics of alien predators.

In contrast, where predators and prey have coexisted for long periods, prey often respond by developing behaviours and bodily defences such as camouflage colouring that reduce detection or help them escape if they encounter a familiar predator.

"The finding brings new insight and urgency to the challenge of how best to target management programs aimed at protecting native species from predation," says Dr Peter Banks, UNSW biologist and report co-author.

"More than a century after the introduction to Australia of predators such as the fox their impact continues, and ongoing predation pressure means that remnant populations of prey animals like numbats and bettongs are more vulnerable to extinction from other pressures such as diseases and habitat loss."

The study assessed the impact on alien predators on populations of animals, birds and reptiles by evaluating 80 high-quality research studies from around the world. Predators ranging in size from wolves, lynx and coyotes down to rats were included.

The research reveals that alien predators have done the most damage in Australia, whose native fauna have long been protected by the continent's geographic isolation. According to the World Conservation Union, Australia has nine of the world's 14 worst invasive mammals (domestic cat, goat, grey squirrel, mouse, pig, rabbit, red deer, red fox, ship rat).

Scientists believe that more frequent contact between predator and prey populations in contiguous continents such as Eurasia, Africa and the Americas has made prey populations less naïve to alien predators by exposing them to similar predator "archetypes".

In contrast, Australia’s unique marsupial fauna have never had predatory species like feral foxes and cats until recently. Such alien predators were shown to have worse negative impacts than some classic predators, including large carnivores such as wolves.

Case study: foxes and the brush-tailed bettong

In the early 1800s, Australia’s brush-tailed bettong - a medium-sized kangaroo-like marsupial - was commonplace in central New South Wales, South Australia and the southern regions of the Northern Territory and Western Australia.

However, the population and range of bettongs began shrinking during the 1900s following the release and spread of foxes and rabbits across the continent. Many other species – up to two dozen -- are thought to have become extinct during this initial wave of invading alien species.

By the 1970s, the bettong was considered as an endangered species with the only surviving mainland populations found in small pockets of forest in Western Australia. However, even these remnant populations were still being preyed upon by foxes and by the late ‘70s the species was threatened with extinction.

Following an intensive program of fox-control initiatives, bettong numbers eventually rebounded by more than 20-fold, demonstrating that fox predation had continued to have a devastating impact on bettongs after more than 150 yeas. No native predator anywhere on earth has had such a profound negative impact on their prey.

Dr Peter Banks | EurekAlert!
Further information:

More articles from Studies and Analyses:

nachricht Diagnoses: When Are Several Opinions Better Than One?
19.07.2016 | Max-Planck-Institut für Bildungsforschung

nachricht High in calories and low in nutrients when adolescents share pictures of food online
07.04.2016 | University of Gothenburg

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Resolving the mystery of preeclampsia

21.10.2016 | Health and Medicine

Stanford researchers create new special-purpose computer that may someday save us billions

21.10.2016 | Information Technology

From ancient fossils to future cars

21.10.2016 | Materials Sciences

More VideoLinks >>>