Hot topics                    

Tuesday 25 March 2008 (Updated 31 March 08)

RAPID ROUNDUP: Kangaroo cull in Canberra – experts react.

The culling of 400 kangaroos on Department of Defence land in Belconnen, Canberra has been mooted for some time.  Many animal welfare charities have called for the animals to be translocated rather than culled. The AusSMC has rounded up wildlife experts to offer a scientific perspective.

March 31 Update: The Dept of Defence has requested to undertake a scientific trial of kangaroo management techniques, including translocation. Pending the ACT Government's response, the proposed cull has been placed on hold. See the Dept of Defence media release.

Feel free to use these comments in your stories. If you would like to speak to one of these or other experts, please don’t hesitate to contact us on (08) 8207 7415 or by email. Any further comments will be posted here as they come to hand.

To read more from two leading kangaroo management experts, visit our Science Blog page.

Dr Graeme Coulson is a senior lecturer in the Department of Zoology at the University of Melbourne. He is an expert in the ecology and management of kangaroo populations and was a member of the expert panel for the Department of Defence which made its recommendations on the site in October 2007.

"The site we were asked to review was a decommissioned defence site with known rare and endangered plants and animals including a native herb and the striped legless lizards. The Department of Defence has an obligation to protect the biodiversity of the area.

The current situation is that the native grasslands have been severely degraded by the presence of too many eastern grey kangaroos. We advised that numbers of kangaroos needed to be drastically reduced in order to protect the biodiversity of the site. Numbers could be reduced by translocation (if suitable release sites could be found), by shooting (if public safety is not compromised) or by darting followed by lethal injection. Grey kangaroos themselves are not an endangered species, and there is no intention to make any commercial use of their carcasses.

From an animal welfare point of view, the kangaroos are now so prolific at the site that it will soon get to the point where the kangaroos themselves will be under threat from over-population. If something had been done 5 years ago, then we wouldn’t have the situation now where so many need to be removed.”

Emeritus Professor Gordon Grigg is an expert in kangaroo population ecology and sustainable management at the University of Queensland. To read his full comment see Science Blogs.

On the issue of translocation:

“Translocation is fraught with practical difficulties (the stress involved with capture, post-capture myopathy which is a serious issue in kangaroos, finding a suitable release site/s) and ethical and legal issues (foreign genetic material and possibly disease introduced at the release site/s; translocation contravenes the policies of most wildlife conservation agencies). Also, introducing animals to a new environment does not guarantee a happy ending. These animals will need to compete with conspecifics and dodge predators and other hazards in unfamiliar surroundings. Even if they survive capture and transport to a new site, survival of translocated animals is often poor. Furthermore the new environment may not respond well to the raised density.”

On lethal injection:

“Darting followed by lethal injection sounds simple and humane, and is probably a good option for small numbers of animals. For animals at high density, because you have to be close to shoot the dart and because it takes time for a dart to take effect, the proximity of the shooters and the odd behaviour of the darted individual all contribute to a stressful situation for the other kangaroos which will hop about frantically in great distress.”

On the parallels to whaling:

“I note that parallels are being drawn between the present situation in the ACT and Australia's opposition to whale hunting by Japan. I can't see the parallels; the whales are free ranging in a natural environment, they are not beyond their carrying capacity and damaging the environment in a confined area, and they are not at risk of running out of food and dying of starvation. The motivation too is markedly different. Something clearly has to be done about the kangaroos on humanitarian and environmental grounds, and quickly, and it is fortunate that (unlike with whales) there is an effective and non-stressful way to reduce the population.”

Dr Greg Baxter is a Senior lecturer in Natural and Rural Systems Management at the University of Queensland.

“A cull – that is reducing the density of kangaroo’s on that land  - seems to be the only rational way to proceed. It will be humane if done correctly. I have reservations about darting them then injecting them because darting them is much more likely to go wrong and cause injury and maim animals rather than a lethal shot from a trained marksman. We know that kangaroo’s can be humanly shot, for example the RSPCA has no welfare issues with the commercial kangaroo harvesting.

There are not any animal welfare issues with a cull but there are issues if we leave them, it is a long lingering death by starvation and will take weeks for them to die. This seems like a very painful and unpleasant way to die and they have the capacity to severely degrade the environment as they are wild animals trying to eke out a living.

The only other way to control the problem is to translocate them but to do that you must take them to somewhere that is suitable kangaroo habitat not already occupied by kangaroo’s – these places do not exist. If you put them somewhere where there already are kangaroo’s you either displace the kangaroos that are already there or  the animals you moved end up displaced themselves and will again face a lingering and prolonged death. On top of this the translocation process is likely to be very traumatic. I think the option of some lethal reduction in numbers is the only way to go and it is not qualitatively different from the commercial kangaroo harvest which kills several million kangaroo’s a year.”

Dr Paul Hopwood is from The University of Sydney`s School of Veterinary Science and is an advisor to Commonwealth and State governments on fauna management policy and to community groups on animal activism/animal welfare issues.

“There is a Commonwealth policy that there should be kangaroos widely distributed across Australia, and it’s a good policy – everyone likes to see kangaroo populations embedded in our environment, with a very wide distribution in abundance. However, there is a point when the animals become over abundant and need to be culled and if kangaroo numbers are not reduced, they cause all sorts of adverse environmental damage.

Red and grey kangaroos are not a threatened species. Despite the fact that Australia’s kangaroo management program is one of the largest cull programs of a large mammal around the world there are probably more kangaroos in Australia than there are people.

Permission to use firearms at the Belconnen site has been denied because of safety concerns regarding close proximity to residential homes. Therefore, a requirement of the contract was to first dart the animals with a tranquilliser dart-gun and the animals be disposed of after that. In actual fact this is a serious misconception, totally unnecessary, and will put the animals through much more stress than is necessary whilst making the culling exercise itself horrendously expensive.

Those animals can be culled very safely with firearms and the way to do it is to put up scaffolding and construct shooting towers so the marksmen are shooting downwards at the animals, so that their projectiles fall to earth and there is no danger to the surrounding neighbourhood. This method will ensure that the animals are killed very quickly and very humanely. With the method that had been proposed at the moment, it is going to be very expensive using dart guns and it is going to stress the animals more and will achieve nothing in relation to conservation benefit.“

Arthur Georges is Professor in Applied Ecology at the University of Canberra, member and former President of each of the Australasian Wildlife Management Society and the Australian Society of Herpetologists and currently serves on several government advisory committees. See his full comment in Science Blogs

On the conservation value of the Belconnen site:

“The Australian Capital Territory has an enviable record for conservation. Canberra is dissected by Canberra Nature Park, home to all manner of native wildlife with all the wonderful and complex interactions that go into making natural vibrant ecosystems. However, these natural ecosystems are embedded in a highly modified environment, often suburbia. Active management is required if their values are to be retained. Some of these ecosystems are endangered nationally, and Canberrans have a special duty to care for them.

Lowland temperate native grasslands are one such endangered ecosystem. Less than 1% of the original grasslands remain intact nationally. Those species of grass and herb that make up the grassland communities, and those animals that depend exclusively on the grasslands, are all in danger of extinction. The ACT is blessed with some of the finest examples of these grasslands.

They are home to the pink-tailed legless lizard, the grassland earless dragon, the striped legless lizard, the golden sun moth, the Perunga grasshopper, and the button wrinklewort daisy, all endangered, all on the edge. The earless dragon is now extinct in Victoria and lost from most of their former range in NSW. The ACT is the last stronghold for this dragon, indeed for many of these species. Yet these endangered species and ecosystems continue to suffer from the tyranny of a thousand cuts.”

Professor Hugh Possingham is a mathematical ecologist, Federation Fellow and the Director of the Ecology Centre at the University of Queensland and the Applied Environmental Decision Analysis Centre.

“Australia has lost or reduced the number of large predators in many areas.  This is common across much of the world where people come in contact with large predators, reduce the numbers of those predators, and cease being a predator themselves.  In these situations some herbivores breed beyond the capacity of the environment to sustain them.  They can have a serious negative impact on biodiversity through over-grazing and habitat degradation.  The solution that is best for the welfare of the animals concerned, and the environment, is invariably a humane cull.”