Reviving Revenant Remnants: Guiding Revegetation Using Metapopulation Modelling for Improving Connectivity in a Fragmented Landscape

Abstract

Habitat connectivity is vital for species population persistence but habitat loss and fragmentation is driving species decline across the globe. In order to respond to this challenge, conservation planners need ecologically relevant information to enable restoration of habitat and connectivity. The aim of this research was to use metapopulation theory and landscape ecology to provide biologically relevant guidance on how to improve landscape connectivity in a fragmented agricultural landscape, through an on-ground revegetation programme. In realising this aim, recently developed but not yet widely utilised methodologies were applied to a real-world conservation investment programme. These methodologies integrated concepts from metapopulation theory and landscape ecology to assess landscapes for their capacity to sustain viable metapopulations of a species of interest. A theoretical advance arising from this research was to develop the dispersal linkages as a stand-alone modelling component, hitherto a feature retained within the metapopulation model. New frameworks and syntheses of methodologies were developed in response to specific investment agency requirements but will have general application elsewhere. The study was conducted in the Border Rivers – Gwydir catchment in northern New South Wales, eastern Australia, as part of the Brigalow–Nandewar Biolinks revegetation project. The regional economy of the study region is based around agriculture (grazing and dryland and irrigated cropping), and native vegetation has been extensively cleared and modified for this purpose, resulting in relictual, fragmented and variegated landscapes.