Who’s been lost from the landscape? Identifying missing terrestrial fauna to inform urban rewilding

Context. Urbanisation has driven native species declines and local extinctions, eroding ecological processes. However, urban areas with remnant native vegetation patches may offer opportunities for native wildlife rewilding. 

Aims. We sought to identify potential urban rewilding candidates across a target landscape. We then examined their ecological traits to understand if those traits were shared by rewilding candidate species. 

Methods. We developed and applied a decision framework to occurrence records of terrestrial, non-volant mammals and reptiles to identify two status groups: (1) extant; and (2) rewilding candidates. Data on four ecological traits (diet, size, habit, and habitat) were then analysed using multivariate statistics. 

Key results. We identified 39 mammal and 47 reptile species historically present, with up to 62% of mammals and 93% of reptiles persisting since 2000. Eighteen species were categorised as locally missing, 11 of which are threatened. Two families (Canidae and Potoridae) were found to be locally extinct. Foraging habit (P-value = 0.047) and diet breadth (P-value = 0.024) were significantly different between our status groups. 

Conclusions. Locally missing and/or declined species represent potential urban rewilding candidates with broadest geographic applicability in patchy urban contexts, and align with a rewilding goal to restore pre-disturbance assemblages. In an urban context, where the list of species lost might be high, additional factors require consideration to aid rewilding candidate prioritisation in resource constrained environments. 

Implications. The decision framework efficiently pinpointed an initial suite of urban rewilding candidates. This framework can be applied by urban conservation managers. Trait analyses highlighted vulnerabilities critical to informing development of successful urban rewilding strategies.