Non-target impacts of poison baiting for predator control in Australia
Article first published online: 31 AUG 2007
Volume 37, Issue 3, pages 191–205, July 2007
How to Cite
GLEN, A. S., GENTLE, M. N. and DICKMAN, C. R. (2007), Non-target impacts of poison baiting for predator control in Australia. Mammal Review, 37: 191–205. doi: 10.1111/j.1365-2907.2007.00108.x
- Issue published online: 31 AUG 2007
- Article first published online: 31 AUG 2007
- Submitted 4 January 2006; returned for revision 6 June 2006; revision accepted 27 February 2007
- invasive species;
- vertebrate pest
- 1Mammalian predators are controlled by poison baiting in many parts of the world, often to alleviate their impacts on agriculture or the environment. Although predator control can have substantial benefits, the poisons used may also be potentially harmful to other wildlife.
- 2Impacts on non-target species must be minimized, but can be difficult to predict or quantify. Species and individuals vary in their sensitivity to toxins and their propensity to consume poison baits, while populations vary in their resilience. Wildlife populations can accrue benefits from predator control, which outweigh the occasional deaths of non-target animals. We review recent advances in Australia, providing a framework for assessing non-target effects of poisoning operations and for developing techniques to minimize such effects. We also emphasize that weak or circumstantial evidence of non-target effects can be misleading.
- 3Weak evidence that poison baiting presents a potential risk to non-target species comes from measuring the sensitivity of species to the toxin in the laboratory. More convincing evidence may be obtained by quantifying susceptibility in the field. This requires detailed information on the propensity of animals to locate and consume poison baits, as well as the likelihood of mortality if baits are consumed. Still stronger evidence may be obtained if predator baiting causes non-target mortality in the field (with toxin detected by post-mortem examination). Conclusive proof of a negative impact on populations of non-target species can be obtained only if any observed non-target mortality is followed by sustained reductions in population density.
- 4Such proof is difficult to obtain and the possibility of a population-level impact cannot be reliably confirmed or dismissed without rigorous trials. In the absence of conclusive evidence, wildlife managers should adopt a precautionary approach which seeks to minimize potential risk to non-target individuals, while clarifying population-level effects through continued research.