Assessing predation risk to threatened fauna from their prevalence in predator scats: dingoes and rodents in arid Australia

• Published in: PloS one Vol. 7; no. 5; p. e36426
• Main Authors: Allen, Benjamin L, Leung, Luke K-P
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 01-05-2012; Public Library of Science (PLoS)
• Subjects: Animal behavior; Animals; Arid zones; Aridity; Australia; Biology; Canis lupus dingo; Conservation of Natural Resources - methods; Dung; Endangered & extinct species; Endangered Species; Fauna; Feces; Food Chain; Geography; Hybrids; Mice; Muridae - physiology; Notomys cervinus; Notomys fuscus; Population Density; Population Dynamics; Populations; Predation; Predation (Biology); Predators; Predatory Behavior - physiology; Prey; Pseudomys australis; Risk Assessment; Risk Factors; Rodentia; Rodents; Threatened species; Wildlife conservation; Wolves; Wolves - physiology; Australia
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0036426

The prevalence of threatened species in predator scats has often been used to gauge the risks that predators pose to threatened species, with the infrequent occurrence of a given species often considered indicative of negligible predation risks. In this study, data from 4087 dingo (Canis lupus dingo and hybrids) scats were assessed alongside additional information on predator and prey distribution, dingo control effort and predation rates to evaluate whether or not the observed frequency of threatened species in dingo scats warrants more detailed investigation of dingo predation risks to them. Three small rodents (dusky hopping-mice Notomys fuscus; fawn hopping-mice Notomys cervinus; plains mice Pseudomys australis) were the only threatened species detected in <8% of dingo scats from any given site, suggesting that dingoes might not threaten them. However, consideration of dingo control effort revealed that plains mice distribution has largely retracted to the area where dingoes have been most heavily subjected to lethal control. Assessing the hypothetical predation rates of dingoes on dusky hopping-mice revealed that dingo predation alone has the potential to depopulate local hopping-mice populations within a few months. It was concluded that the occurrence of a given prey species in predator scats may be indicative of what the predator ate under the prevailing conditions, but in isolation, such data can have a poor ability to inform predation risk assessments. Some populations of threatened fauna assumed to derive a benefit from the presence of dingoes may instead be susceptible to dingo-induced declines under certain conditions.