Crest-tailed mulgara

Dasycercus cristicauda

Blamed on foxes

IUCN status: Vulnerable

EPBC Predator Threat Rating: High

IUCN claim: “Threats are poorly understood but include predation by and competition with feral cats and Red Foxes,”

Studies in support

Pedler et al. (2016) documented fox decline and mulgara increase in occurance and occupancy when rabbits declined. Mulgara were found in foxes’ diet (Mahon 1999; Paltridge 2002; Paltridge 2005; Cupples et al. 2011). Mulgara were last confirmed in the Nullarbor 8-23 years after foxes arrived (Wallach and Lundgren 2025).

Studies not in support

Dickman et al. (2001) found that rainfall, rather than foxes, was the main predictor of mulgara abundance. Mulgara were last confirmed in the Western Division of NSW 11 years before, to 14 years after, foxes arrived (Wallach and Lundgren 2025).

Is the threat claim evidence-based?

Negative correlation between cats and mulgara abundance was documented in one study. Causality for decline is uncertain due to confounding variables (e.g. rabbits, rainfall). In one region it cannot be verified that extirpation occurred after fox arrival.

Evidence linking Dasycercus cristicauda to foxes. A. Systematic review of evidence for an association between Dasycercus cristicauda and foxes. Positive studies are in support of the hypothesis that foxes contribute to the decline of Dasycercus cristicauda, 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 foxes. Error bars show minimum and maximum extinction intervals. Predator arrival records were digitized from Fairfax 2019. See methods section in Wallach and Lundgren 2025 for details on evidence categories.
Evidence linking Dasycercus cristicauda to foxes. A. Systematic review of evidence for an association between Dasycercus cristicauda and foxes. Positive studies are in support of the hypothesis that foxes contribute to the decline of Dasycercus cristicauda, 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 foxes. Error bars show minimum and maximum extinction intervals. Predator arrival records were digitized from Fairfax 2019. See methods section in Wallach and Lundgren 2025 for details on evidence categories.

References

Dickman, C.R., Haythornthwaite, A.S., McNaught, G.H., Mahon, P.S., Tamayo, B. and Letnic, M., 2001. Population dynamics of three species of dasyurid marsupials in arid central Australia: a 10-year study. Wildlife Research, 28(5), pp.493-506.

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).

Fairfax, Dispersal of the introduced red fox (Vulpes vulpes) across Australia. Biol. Invasions 21, 1259-1268 (2019).

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

Mahon, P.S., 1999. Predation by feral cats and red foxes and the dynamics of small mammal populations in arid Australia. PhD thesis, University of Sydney, Sydney, Australia.

Paltridge, R., 2002. The diets of cats, foxes and dingoes in relation to prey availability in the Tanami Desert, Northern Territory. Wildlife Research, 29(4), pp.389-403.

Paltridge, R.M., 2005. Predator-prey interactions in the spinifex grasslands of central Australia. PhD Thesis, University of Wollongong

Pedler, R.D., Brandle, R., Read, J.L., Southgate, R., Bird, P. and Moseby, K.E., 2016. Rabbit biocontrol and landscape‐scale recovery of threatened desert mammals. Conservation Biology, 30(4), pp.774-782.

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