Control of native and introduced animals causing damage to agriculture or habitat

Policy

The control of over abundant animals, both native and introduced, may be justified to prevent and address adverse impacts on agriculture or the environment. Methods can involve harvesting, culling, poisoned baits or biological control, or combinations of these, provided they are highly effective, and applied at times when populations are naturally at their lowest to minimise the number of individual animals impacted over time.  Further research is required to identify new control options for pest animal species.

Background

A large number of native and introduced animals have become abundant and are regarded as pests in Australia, because of their potential to damage agricultural lands and natural ecosystems.

Harvesting, culling and biological control are common tools used in management programs for animals regarded as pests. These controls are defined as follows.

• Harvesting is the taking of free-living animals for commercial, community or personal use.
• Culling is a procedure used primarily to reduce the population size of free-living animal species, and may or may not involve the utilisation of some or all of the animals that are killed.
• Biological control generally implies the use of microorganisms or vertebrate or invertebrate predators but can also include modified reproduction.

Control programs should aim to identify and minimise the unwanted impact of the pest species rather than simply controlling the species itself.

Harvesting and culling can be legitimate methods to reduce the impacts of introduced animal species, such as the rabbit, fox, cat, pig, goat, buffalo, camel and horse. Harvesting and culling can also be applied to designate ‘game species’ like deer for which there are game management plans. It also applies to certain native species where there may or may not be evidence of overpopulation. The commercial harvesting of designated species of kangaroos and wallabies is an example.

At present, eradication of the major feral animal species is unlikely, except on off-shore islands and in predator-proof enclosures. The development of a wider range of effective and humane control options for pest animals is the subject of significant research effort in Australia and needs to be backed up with public education and oversighting legislation.

Guidelines

The following guidelines should be observed for harvesting, culling and biological control programs.

• Harvesting, culling and biological control programs must have a firm scientific basis and take account of animal welfare.
• Programs should be rigorously evaluated and subjected to community consultation before being implemented and should be specific for the target species.
• The commercial harvesting in some states and territories of certain large macropod species is carried out under a National Code of Practice for the Humane Shooting of Kangaroos and Wallabies (2008) as this sustainable harvest of kangaroos and wallabies provides significant revenue to rural communities across Australia as does the hunting of species of deer and feral pigs.
• The live capture of pest animals such as feral goats as part of a control program should be restricted to accredited operators who have received appropriate training, including veterinary advice. The decision on whether to attempt capture should take into account the risk of injury and stress to the animals during capture, subsequent handling and transport, as euthanasia may be preferable in some circumstances.
• Methods used to kill animals must be rapid and humane and participants in harvesting and culling programs must be adequately trained and demonstrate competency in killing methods approved for the program, such as the National Code of Practice for the Humane Shooting of Kangaroos and Wallabies (2008), with the head being the specified target. This code of practice stipulates head shots for those who obtain permits to cull macropods, but this raises concerns about the ability of non-professional shooters to consistently deliver a lethal shot to the head at longer ranges. The chest kill zone is a much more humane option for those culling kangaroos, with a suitable high velocity projectile targeting the heart, associated large vessels or the lungs.
• If an animal is suspected of being alive after being shot, every reasonable effort must be made to locate and kill it immediately.
• Biological control agents should have minimal effect on the normal behaviour and demeanour of the animal (unless such effects are part of the control objective). Where agents will cause death of some animals, death should be as rapid and as free from pain, apprehension or disorientation as possible. The level of these undesirable effects should be comparable with, or less than, effects caused by non-biological control agents. Individuals that recover should be minimally affected.
• Biological control agents must have no effect on non-target species.
• The seasonal breeding patterns of feral and native animals should be taken into account when control programs are planned. Killing or capture of breeding females with unweaned offspring should be avoided. Killed females should be checked for unweaned offspring which must be located immediately and killed humanely. 
• Free living fauna may harbour diseases transmissible to humans or other animals.  Brucellosis due to Brucella suis in feral pigs is an example. Harvesting and culling protocols must be designed to prevent disease transmission.

The AVA does not support the use of steel-jawed traps for killing foxes or dingoes (or any other animal) or for capture of these animals prior to killing. It is an inhumane method that causes injury and suffering to target species as well as to non-target species. Death is often slow and results from a combination of exposure, exhaustion and shock.

Other relevant policies and position statements

• Management of cats in Australia
• Control of feral horses and other equidae
• Control of wild rabbits
• Kangaroo and wallaby population control
• Harvesting and culling of native fauna

Date of ratification by AVA Board 15 October 2010