Controlling feral animals such as rabbits, goats and camels could provide a cost-effective contribution to Australia’s greenhouse gas emissions targets while also generating important benefits for agricultural productivity, regional communities and the environment.
Australia has committed to a 5% greenhouse gas emissions reduction target by 2020. The capture and storage of atmospheric carbon in vegetation and soils (biosequestration) is widely accepted as an important means of achieving this target. To date, most attention regarding biosequestration has focused on encouraging tree planting, managing livestock grazing pressure and the adoption of modified agricultural practices. However, it is highly desirable to develop alternative methods that may prove more cost-effective or capable in different contexts, particularly in an uncertain policy environment.
Invasive herbivores, such as feral rabbits, camels and goats can have significant adverse impacts on the biosequestration potential of native vegetation communities and ecosystems. It is possible to reverse many of these impacts by reducing herbivore abundance, and this should increase sequestration rates. There has been some discussion of the potential for directly reducing emissions by reducing the abundance of methane emitting species such as feral camels, but any emissions avoided by this approach could not count towards Australia’s targets under current international agreements. Conversely, enhanced biosequestration resulting from increased vegetation growth due to invasive herbivore control would be accountable, but this approach has largely been ignored in Australia.
Examination of the damage caused by feral rabbits, camels, goats and pigs strongly suggests that control of invasive herbivores at large scales has the potential to make significant contributions to emissions reduction targets. However, the likely magnitude of carbon sequestration benefits that could be achieved has not yet been established.
In many cases, herbivore control programs might provide a more cost-effective and practically feasible means of enhancing biosequestration than active tree planting. Rabbits are likely to be the most useful subject for herbivore control programs because many of their impacts on vegetation are well understood; the potential for vegetation recovery after rabbit control has been demonstrated; and a research program to further develop biological control tools that will have continental scale impacts is underway. Importantly, the broadscale suppression of rabbit populations would also have major co-benefits for agricultural productivity, regional communities and the environment. Realisation of these benefits will depend on the development of a sound understanding of the technical and achievable potential for invasive herbivore control to contribute to emissions abatement, and the availability of institutional conditions to promote adoption.
Produced by the Invasive Animals Cooperative Research Centre as part of the PestSmart series.
|Author||Andrew Bengsen and Tarnya Cox|
|Publisher||Invasive Animals CRC|
|ISBN/ISSN||Web ISBN: 978-1-921777-75-2|
|Region||Australia - national|