Document ID: chunk:federal_register_of_legislation:F2024L01747:reg:4:p54
Version: federal_register_of_legislation:F2024L01747
Segment Type: reg
Provision Reference: reg 4 (pt 54/80)
Character Range: 189302–192354

compared to existing feral cat control options. The options include using immunocontraception and gene drives to reduce feral cat populations. None are likely to be operative within the lifetime of this plan, but progress towards their development and evaluation should be maintained.

Disease has been used to help achieve eradications of cats from islands in other countries, but disease is unlikely to lead to eradication of feral cats from the Australian mainland because the large size of the continent means the probability that disease-resistant individuals occur somewhere, survive the disease and breed disease-resistant offspring, is high. Disease could be used to reduce feral cat population size but may be considered unacceptably inhumane.

Trials of immunocontraception have been undertaken in the past, some are still underway, and the approach may be useful in some situations (e.g. for island eradications).

Synthetic biology offers opportunities for new approaches to reducing feral cat populations. Synthetic biology aims to redesign animals, or biological systems, to produce novel functions. Genetic engineering, which involves manipulating the genome of individual animals, is an example of synthetic biology. There is currently considerable interest in a particular application of genetic engineering called gene drives, where gene sequences are inserted into individual animals that then propagate through populations with each reproductive event. For example, gene drives could be used to make feral cats more susceptible to a toxin, or to skew the sex ratio towards one sex, or to make carriers of the gene sterile. Releasing gene drives into the feral cat population is a complex problem, with many components, that will take more than 20 years and a multidisciplinary effort to reach the point of release, with impacts on the feral cat population size evident only after many cat generations. The main barriers to developing and implementing gene drive technologies include: technical (molecular and ecological) knowledge gaps; implementation knowledge gaps; legislation, policy and regulation misalignments and gaps; and, public acceptance and ethics.

The susceptibility of native species to cats is exacerbated by the lack of co-evolutionary history and thus predator naivety. Potentially, natural selection can be simulated to encourage predator recognition and avoidance behaviour in cat-susceptible species by exposing populations of native species to controlled levels of cats. Trials of this possibility have been undertaken at Arid Recovery (South Australia) and Wild Deserts (New South Wales (NSW)), with a related trial carried out in the Australian Capital Territory (ACT) (with a focus on foxes rather than cats). These trials have revealed shifts in morphology and behaviour of some wildlife species, consistent with improvement in predator avoidance capability. However, it is unclear how far such predator recognition and avoidance can be pushed in these native species, especially given the reduced genetic