Niche Environment and Heritage was engaged by North West Local Land Services (NWLLS) to assess biodiversity assets using GIS-based habitat assessments and species distribution modelling. The project was undertaken across the entire NWLLS area which stretches from the New England Tablelands to the semi-arid northwest plains of New South Wales.
Niche assessed biodiversity values at a landscape level using two distinct but integrated approaches. The first was a GIS-based landscape ecology assessment, establishing and classifying links between vegetation patches, conducting connectivity analysis, building an intactness layer using raster-based moving window analysis and digitising locations of regional corridors for species migration in response to local disturbance and climate change. The GIS methodology built on a previous Namoi CMA study.*
The second component was a spatial statistics analysis and modelling process using threatened species’ location, along with predictor variable layers including vegetation-habitat, soil and geology, topography and insolation, and rainfall. Presence-only spatial modelling is a relatively new but robust and beneficial field of habitat analysis, and is demonstrably more reliable in species distribution prediction than traditional GIS overlay processes.
An at-a-glance assessment of the biodiversity assets of the NWLLS
The project outcomes allow an at-a-glance assessment of the biodiversity assets of the NWLLS, as well as providing a basis for investment in biodiversity management and a range of related NWLLS programs.
The integration of species distributions and habitat values for species at a landscape level is critical for informed biodiversity planning but challenged by a range of data limitations.
The project required extensive collaboration between Niche’s highly experienced in-house GIS specialists and species modelling experts, combined with large data processing capabilities.
The project highlighted the importance of large landscape remnants such as the Pilliga Forest and the Kaputar region and the important contribution of less intact landscapes in the maintenance of regional habitat connectivity.
Thanks to the Niche team’s extensive experience in both GIS and ecological assessment and modelling techniques, we were able to provide NWLLS with a solid basis for the further development of biodiversity prioritisation.
*Assessing the cumulative risk of mining scenarios on bioregional assets in the Namoi Catchment: Development and trial of an interactive GIS tool. Prepared for Namoi Catchment Management Authority (2012).