Threat abatement project (2011-12 component; ID: 1011-0878)
About the report
Poison baits, known as Curiosity®, that contained the toxicant paraminopropiophenone (PAPP) were distributed from the air over a 150 km2 area of the Pantapinna Plain, Flinders Ranges National Park (South Australia). Twenty feral cats (Felis catus) had previously been trapped, fitted with radiotelemetry collars and released within the field site. Two of these cats died following consumption of Curiosity® bait(s) while one other had died prior to bait application. A further two cats were later confirmed to have consumed some or all of a bait but survived.
Replicated spotlight surveys conducted prior to and following bait application indicated that the overall feral cat population had decreased by 50%. Analysis of data collected with automated cameras indicated that there had been a 16% decrease in occupancy during the post-baiting survey. The actual decrease in the feral cat population is expected to fall within the range indicated by these indices.
An irruption in populations of plague locust (Chortoicetes terminifera) and then house mice (Mus musculus) in the months preceding this study is thought to have to led to an increase in and then subsequently sustained the feral cat population. Analysis of dietary items identified in the stomachs and scats of feral cats indicated that house mice were the dietary staple. Feral cats prefer live prey with optimal consumption of baits occurring during periods of food stress. The abundance of live prey at this study site may have contributed to the apparent low levels of bait uptake by feral cats.
Populations of non-target bird species were assessed prior to and following baiting using counts along a driven transect as well as five minute point counts. Decreases were observed in counts of species such as the wedge-tailed eagle (Aquila audax) however it is considered that as these birds are highly mobile in the landscape with their presence on the site linked to food availability.
Laboratory assessments of the bait and toxicant conducted following the field trial indicated that the baits used were 'fit for purpose', i.e. accurate dosing of PAPP per bait, baits palatable etc. Similarly, pen trials conducted with captive feral cats demonstrated that baits used in the field trial were efficacious.
Land managers intending to undertake management of feral cat populations using baiting should be aware of the abundance of prey populations prior to applying baits. Optimal efficacy will be achieved using an attractive and palatable bait that is distributed during a period when alternative food sources are minimised.