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

Policy

1. Control programs to protect the environment, social amenity and agriculture from invasive animals must be carried out humanely. They must use best practice methods based on scientific research, and must include monitoring and assessment for continual improvement.
2. Humane control standards must be enshrined in legislation and methods known to be inhumane must not be used in Australia.
3. Continual research must be undertaken to identify more humane options for control of pest animal species.

Background

A large number of introduced animal species cause damage to natural ecosystems and agricultural lands. There are potential economic, conservation and welfare consequences if we fail to control these pest species.

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. Scientific literature suggests that recreational hunting and commercial harvesting alone have not been effective in limiting populations of pest animals or overabundant wildlife in Australia (Gentle et al. 2011, Grigg & Pople 2001, Pople & Froese 2012, Pople & Grigg 1998) or overseas (Simard et al. 2013, VerCauteren et al. 2011, Sinclair 1997). However, in certain circumstances, targeted hunting may be effective in keeping populations in check (Hall & Gill 2005).
• 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 methods.

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 results are published and disseminated through State Governments and the Pest Smart website.

Recommendations

All control must be consistent with the Model codes of practice for the humane control of pest animal species and these codes should be adopted into all State government animal welfare legislation.

Control programs must have a firm scientific basis and take account of animal welfare. Methods should be rigorously evaluated and subjected to community consultation before being implemented and should be specific for the target species.

Control programs should aim to identify and minimise the unwanted impact of the pest species rather than simply controlling the species itself. The number of animals culled is not an indication of outcomes. Programs must be subject to monitoring and assessment of outcomes, including any unintended consequences, with a view to reassessing and updating controls accordingly. This in order to ensure efficacy and compliance with humane principles at all times.

Where possible, programs should be planned around seasonal breeding to minimise welfare impacts on unweaned offspring.

Decisions about the method of control should be guided by the Model for assessing the relative humaneness of pest animal control methods (Sharp and Saunders, 2008)

It is noted that rodent control is not covered in this model and there are no Codes of Practice or Standard Operating Procedures for rodents. Therefore, the AVA advocates the development of guidance documents for rodents.

Methods used to kill animals must be rapid and humane; participants in harvesting and/or culling operations must be adequately trained and demonstrate competency and methods used must have minimal effect on non-target species. Operators should also be aware of, and take precautions against diseases that can be transmitted from feral animals to humans or domestic animals (eg Brucella suis can be transmitted to humans or domestic dogs).

Landholders should be encouraged to undertake control programs in conjunction with neighbouring landholders (including crown lands) to maximise the effectiveness of the control program.

Biological control agents must 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.

There are five methods of control currently available that have been assessed as inhumane (Sharp and Saunders 2008) and should not be used in Australia. These are

• CSSP (yellow phosphorus) for pig control
• Strychnine bait for dogs, foxes and cat
• Unmodified serrated jawed traps
• Warfarin bait for pigs
• Chloropicrin fumigation for rabbits

The use of glue boards or drowning for rodent control is also inhumane (Mason and Litten 2003) and should not be used.

References

1. Gentle M, Pople T, Speed J et al. Assessing the Role of Harvesting In Feral Pig (Sus Scrofa) Management: Final Report To The Queensland Murray–Darling Committee. Robert Wicks Pest Animal Research Centre, Biosecurity Queensland, Toowoomba, 2011.
2. Grigg GC, Pople AR. Sustainable use and pest control in conservation: kangaroos as a case study. In: Reynolds J, Mace G, Redford K et al, editors. Conservation of Exploited Species. Cambridge University Press, Cambridge, 2001;403–423.
3. G. J. Mason & K. E. Littin (2003). The humaneness of rodent pest control. Animal Welfare 12: 1 – 37.
4. Pople AR, Grigg, GC. Commercial Harvesting of Kangaroos in Australia. Environment Australia, Canberra, 1998. http://www.environment.gov.au/biodiversity/wildlife-trade/publications/kangaroo/harvesting/index.html.
5. Pople T, Froese J. Distribution, Abundance and Harvesting of Feral Goats in the Australian Rangelands 1984–2011: Final Report To The Acris Management Committee. Queensland Department of Employment, Economic Development and Innovation, Alice Springs, 2012. http://www.environment.gov.au/land/publications/acris/pubs/acris-goats-r....
6. Simard MA, Dussault C, Huot J et al. Is hunting an effective tool to control overabundant deer? A test using an experimental approach. J Wildl Manage 2013;77:254–269. http://onlinelibrary.wiley.com/doi/10.1002/jwmg.477/abstract.
7. Management. Smithsonian Institution Press, Washington, 1997;380–394.
8. VerCauteren KC, Anderson CW, van Deelen TR et al. Regulated commercial harvest to manage overabundant white-tailed deer: an idea to consider? Wildl Soc Bull 2011;35:185–194.
9. Model Codes of Practice for the humane control of pest animal species https://www.pestsmart.org.au/animal-welfare/humane-codes/ assessed 17/02/2018
10. Sharp, T and Saunders, G (2008). A model for assessing the relative humaneness of pest animal control methods. Australian Government Department of Agriculture, Fisheries and Forestry, Canberra, ACT.

Other relevant policies and position statements 

Management of cats in Australia

Control of feral horses and other equidae

Kangaroo and wallaby population control

Harvesting and culling of native fauna

Date of ratification by AVA Board 7 December 2018