MAKING TRACKS

NEW APPROACHES TO MODELLING DISPERSAL PATHWAYS AND KOALA HABITAT CONNECTIVITY

Amanda Lane; Alex Lechner; Kirsty Wallis; Stephen Phillips

Regional Scale Connectivity

Key Habitats and Corridors (KHC) North-east NSW

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G eneralisedA pproach toP lanning

C onnectivity fromL ocaloS cales toR egional

Lechner and Lefroy (2014): University of Tasmania and National Environmental Research Program

Graphic taken from GAP CLoSR: conservation outcomes at regional scale in the Lower Hunter. National Environmental Research Program.

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Lechner and Lefroy (2014): University of Tasmania and National Environmental Research Program

Graphic taken from GAP CLoSR: conservation outcomes at regional scale in the Lower Hunter. National Environmental Research Program.

Habitat patches

Least-cost dispersal pathways

Landscape components

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Southern Cross University

Golf course

Wilsons River

Commercial Centre

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Cadastre

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CadastreVegetation

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CadastreVegetationHydrology

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CadastreVegetationHydrologyRoads

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CadastreVegetationHydrologyRoadsGap-crossing threshold

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Satellite imagery Cost dispersal surface

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Cost Dispersal Surface

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GAP CLoSR ResultsSingle landscape component

Habitat patches

Least-cost dispersal pathways follow;

Scattered trees

Windrows in orchards

Roadside and remnant native vegetation

Thin lines of trees in urban areas

Across roads

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GAP CLoSR Results – Vehicle-strike blackspots

High density of least-cost dispersal pathways at vehicle-strike blackspots

Modelled pathways match areas that koalas actually traverse

Action - support connectivity by addressing vehicle-strike

Km of road with the highest vehicle-strike in LGA runs directly through

the second most important dispersal pathway (dIIC score)

dIIC score – delta Integral Index of Connectivity

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GAP CLoSR Results: losing dispersal pathways

Connectivity Attributes No. Elements

Landscape components 1

Habitat patches 197

Least-cost pathways 555

Connectivity Attribute No. Elements

Landscape Components 1

Habitat patches 249

Least-cost pathways 795

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GAP CLoSR Results: pinch points for dispersal

Koala hub relies on one pathway

Can it be secured / restored?

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Modelling koala habitat connectivity

Utility of GAP CLoSR

Assess impacts of land use changes

Inform road placement

Optimal locations for vehicle-strike mitigation

Identify pinch-points and direct restoration efforts

Where to now?

Keep refining cost metrics

Use in concert with regional corridors

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Acknowledgements

Alex Lechner

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ReferencesBiolink. (2019). Koala Connectivity: Identifying least-cost dispersal pathways for koalas within the Lismore Comprehensive Koala Plan of Management (CKPoM). Report to Lismore Council. Biolink Ecological Consultants, Uki, NSW.

Biolink. (2018). Koala Corridor Project: Campbelltown & Wollondilly Local Government Areas. Report to NSW Office of Environment & Heritage. Biolink Ecological Consultants, Uki, NSW.

Phillips, S. Lane, A. and Wallis, K. (2017). Managing koala populations for the future: constituent populations of the Central ARKS Port Stephens sub-area. Report to Port Stephens Council. Biolink Ecological Consultants, Uki, NSW.