Plains rat

Pseudomys australis

Blamed on cats

IUCN status: Vulnerable

EPBC Predator Threat Rating: Very high

IUCN claim: “Recent research has demonstrated marked detrimental impact of introduced predators: Red Fox (Vulpes vulpes) and feral Domestic Cats (Felis catus)”

Studies in support

Plains rats were more common inside a predator-proof fenced area compared to the cattle station outside (Read & Cunningham 2010; Moseby et al. 2020). Cats hunt rats (Pavey et al. 2008; Pavey et al. 2014). Rats were last confirmed at Koonchera Dune, SA, 51-61 years after cats arrived (Wallach and Lundgren 2025).

Studies not in support

Rats were last confirmed in NSW 40-10 years before cats arrived (Wallach and Lundgren 2025).

Is the threat claim evidence-based?

The higher plains rat abundance outside a predator-proof fence is striking. However, certainty is low because data comes from a single study and the area outside is a cattle station. In one region the extirpation record pre-dates the cat arrival record.

Evidence linking Pseudomys australis to cats. A. Systematic review of evidence for an association between Pseudomys australis and cats. Positive studies are in support of the hypothesis that cats contribute to the decline of Pseudomys australis, negative studies are not in support. Predation studies include studies documenting hunting or scavenging; baiting studies are associations between poison baiting and threatened mammal abundance where information on predator abundance is not provided; population studies are associations between threatened mammal and predator abundance. Gold borders indicate studies that meet qualities of scientific rigour. B. Last records of extirpated populations relative to earliest local records of cats. Error bars show minimum and maximum extinction intervals. Predator arrival records were digitized from Abbott 2008. See methods section in Wallach and Lundgren 2025 for details on evidence categories.
Evidence linking Pseudomys australis to cats. A. Systematic review of evidence for an association between Pseudomys australis and cats. Positive studies are in support of the hypothesis that cats contribute to the decline of Pseudomys australis, negative studies are not in support. Predation studies include studies documenting hunting or scavenging; baiting studies are associations between poison baiting and threatened mammal abundance where information on predator abundance is not provided; population studies are associations between threatened mammal and predator abundance. Gold borders indicate studies that meet qualities of scientific rigour. B. Last records of extirpated populations relative to earliest local records of cats. Error bars show minimum and maximum extinction intervals. Predator arrival records were digitized from Abbott 2008. See methods section in Wallach and Lundgren 2025 for details on evidence categories.

References

Abbott, The spread of the cat, Felis catus, in Australia: re-examination of the current conceptual model with additional information. Conservation Science Western Australia 7 (2008).

EPBC. (2015) Threat Abatement Plan for Predation by Feral Cats. Environment Protection and Biodiversity Conservation Act 1999, Department of Environment, Government of Australia. (Table A1).

IUCN Red List. https://www.iucnredlist.org/ Accessed June 2023

Moseby, K.E., McGregor, H., Hill, B.M. and Read, J.L., 2020. Exploring the internal and external wildlife gradients created by conservation fences. Conservation Biology, 34(1), pp.220-231.

Pavey, C.R., Cole, J.R., McDonald, P.J. and Nano, C.E., 2014. Population dynamics and spatial ecology of a declining desert rodent, Pseudomys australis: the importance of refuges for persistence. Journal of Mammalogy, 95(3), pp.615-625.

Pavey, C.R., Eldridge, S.R. and Heywood, M., 2008. Population dynamics and prey selection of native and introduced predators during a rodent outbreak in arid Australia. Journal of Mammalogy, 89(3), pp.674-683.

Read, J.L. and Cunningham, R., 2010. Relative impacts of cattle grazing and feral animals on an Australian arid zone reptile and small mammal assemblage. Austral Ecology, 35(3), pp.314-324.

Wallach A.D., Lundgren E.J. (2025) Review of evidence that foxes and cats cause extinctions of Australia’s endemic mammals. BioScience. DOI: 10.1093/biosci/biaf046