Document ID: chunk:federal_register_of_legislation:F2024L01747:reg:4:p16
Version: federal_register_of_legislation:F2024L01747
Segment Type: reg
Provision Reference: reg 4 (pt 16/80)
Character Range: 47058–49929

Predation

Cats are one of the world's most invasive species, having reached every continent (including Antarctica, as pets) and many islands. They have been the primary or a major cause of over a quarter of the world's bird, reptile and mammal extinctions since the year 1600. Cats have caused profound species loss in Australia, helping to give Australia the worst mammal extinction rate of any country in modern times: over 10% of the Australian terrestrial mammal species extant 250 years ago are now extinct. Of the 33 Australian mammal species rendered extinct since European colonisation, cats have mostly or substantially contributed to two-thirds of these losses. Examples of these extinct species include the pig-footed bandicoots Chaeropus spp., lesser bilby Macrotis leucura, broad-faced potoroo Potorous platyops, bettongs Bettongia spp., hopping mice Notomys spp. and rabbit-rats Conilurus spp. Cats have also contributed to 3 of 9 extinctions of Australian bird species since 1788.

Cats continue to drive population decline in Australian native animal species. Predation by cats is a recognised threat to over 200 nationally threatened species, and 37 listed migratory species (of which 9 are also listed as threatened) (Appendix 1).

With many decades of research, there is now more information on the diet of feral (and pet) cats in Australia than for any other country. Many recent analyses have compiled and analysed such information from tens of thousands of cat dietary samples. These studies have found that feral cats in Australia kill over 1.5 billion native mammals, birds, reptiles and frogs, and 1.1 billion invertebrates each year. Pet cats kill over 320 million native vertebrate animals each year in Australia. Although their overall toll is lower than that imposed by feral cats, because pet cats live at high density, their 'local' impacts can be much higher than that of feral cats.

Refer to section 4.1 of the background document for further information and referenced sources.

     4.1.1 Which extant native species are most susceptible to cat predation?

The predation toll (impact via predation) from cats falls unevenly across species – small- to medium-sized (i.e. up to ~4 kg) terrestrial mammals, ground-dwelling or ground-nesting birds, and colonial reptiles are all more likely to be preyed on by cats. In addition, species occurring in more open, arid environments are more likely to be preyed upon. However, the likelihood of being eaten by a cat does not necessarily translate to the impact on the population, because prey species vary in their capacity to bear the predation burden from cats. For example, species with faster reproductive rates may be able to compensate for the predation toll from cats more readily than species with lower reproductive outputs.

The susceptibility of native species to cat predation is