Europeans introduced Feral Cats (Felis catus) to Australia and New Zealand (Abbott 2002). Early records (relative to European settlement) of feral cats in central Australia suggest their distribution expanded rapidly and the species now occupies most terrestrial habitats. Feral cats are carnivores with exceptional hunting ability and have been implicated in the decline and extinction of taxa from islands and mainlands of both Australia and New Zealand (Dickman 1996; Medina et al. 2011). However, the extent and significance of the damage that feral cats cause is poorly quantified.
Mammals and birds are particularly common prey items of cats, although herpetofauna and invertebrates also are consumed (Jones and Coman 1981; Martin et al. 1996; Paltridge et al. 1997; Risbey et al. 2000; Read et al. 2001). There is emerging evidence that some individual cats become highly specialised predators. This is particularly concerning in situations such as seabird breeding islands where a significant proportion of a prey population is concentrated on a limited resource. Too little is currently known about variation in feral cat home range, movements, habitat use and reproductive biology across the range of habitats and ecosystems feral cats occupy in the southern hemisphere (Edwards et al. 2001; Molsher et al. 2005; Bengsen et al. 2012). Research is required to fill these significant knowledge gaps.
Feral cats are known to carry and spread diseases, e.g. Toxoplasma gondii, that threaten wildlife, humans and livestock (Fancourt et al. 2014). Because of the cross-over between feral, stray and domestic cats, the risks posed by disease are significant and the potential for inter-breeding is high (Calver et al. 2011). Feral cats are listed as a key threatening process in Australia under the EPBC Act (1999) and a national threat abatement plan is in place to guide feral cat management (Dept. of the Environment 2015). Feral cat control has been achieved on islands but at a significant financial cost. On the mainland of Australia and on the main islands of New Zealand, feral cats are one of few invasive species for which viable broad-scale control techniques remain elusive (Algar et al. 2007; Hetherington et al. 2007; Christensen et al. 2013).
Based on the above, THE AUSTRALASIAN WILDLIFE MANAGEMENT SOCIETY:
RECOGNISES that feral cats are a serious threat to Australian and New Zealand biodiversity and that in some circumstances they may pose a serious threat to livestock industries and human health. Preparation of nationwide strategies for managing their impacts is required to prioritise and undertake effective management actions as well as to identify knowledge gaps and conduct appropriate scientific experiments to determine effective management techniques.
RECOGNISES that, to date, too little is known about feral cat biology across the range of occupied habitats. As a consequence, there is limited access to effective monitoring and control methods for this species. What is critical is that management agencies recognise the variety and heterogeneity of behaviours and ecological functions displayed by feral cats.
RECOGNISES that feral cats are highly adaptive and capable of considerable ecological plasticity according to site conditions, and that an adaptive approach including a range of methods will need to be developed, tested and proven in order to effectively monitor and manage feral cat populations.
RECOGNISES that dingoes, other wild dogs, foxes, feral cats, Tasmanian devils and quolls interact in ecosystems as mammalian predators and that these ecological relationships are important in understanding interactions and responses to pest management activities. Similarly, avian predators, snakes and varanid lizards are all likely interact with cats, and vice versa, with varying effects.
ACKNOWLEDGES that, whilst there are recommended methods for monitoring and managing feral cat populations, these are less effective than is desirable and that robust research will be required to develop better techniques.
ACKNOWLEDGES that the eradication of feral cats on islands has been achieved and can continue to be successful on other islands; however mainland eradication is not feasible with existing techniques.
ACKNOWLEDGES that cat management is a highly controversial issue amongst the community, with some stakeholders opposing any control of feral cats, and opposing any regulation on companion animal management. Community stakeholders must have a role in contributing towards the development, implementation and communication of cat management actions.
ACKNOWLEDGES that considerably more research is required to better understand the interactions between feral cats, other predators and prey species, in order to inform and facilitate best practice management.
Accordingly, AWMS recommends that:
Paul Meek, NSW DPI, Vertebrate Pest Research Unit, Coffs Harbour.
Guy Ballard, NSW DPI, Vertebrate Pest Research Unit, Armidale.
Peter Fleming, NSW DPI, Vertebrate Pest Research Unit, Orange.
John Tracey, NSW DPI, Vertebrate Pest Research Unit, Orange.
This position statement reflects the content of cited papers and the opinions of the authors. While the views expressed in this position statement have been circulated for comment within the Society, they do not necessarily reflect the views of all the AWMS members. AWMS makes no claim as to the accuracy of this document and any party using this information does so at their own risk.
Reviewed: June 2015