Historic-Habitat Selection and Post-Reintroduction Population Biology of the New Holland Mouse

Abstract

The historic distribution of the New Holland Mouse, coupled with the ecological shifts associated with Australian colonisation, suggests the species currently resides in refuge habitats. Current habitat models for the New Holland Mouse are based on its extant distribution, describing the species as an early successional post fire habitat specialist of select coastal vegetation. This study describes the first account of habitat selection by the species postreintroduction into an historic environment, and in absence of exotic predation. A novel method for detection of the species was developed and used to reveal habitat preferences that differ from current habitat models, and genetic diversity was also assessed at three stages of the reintroduction using microsatellite analysis. Findings suggest that the means by which the species is able to persist in an historic environment leaves it pre-disposed to exotic predation, more so than in current locations. Loss of genetic diversity and an increased inbreeding coefficient was identified during the captive breeding phase. The current population size is seemingly small with only fourteen individuals identified, and allelic richness has also declined. The introduction of additional founders is suggested to increase population size and insure gene flow. In light of this study, more diverse potential habitat for the species has been identified, subsequently expanding on our knowledge on the fundamental ecology of the species prior to European settlement. Furthermore, this study highlights the potential to incorporate historic habitat in modelling for species recovery programs, and presents a holistic framework for assessing post-reintroduction population biology, to best inform on past methods and future management action.