A 6-year study of mitigating koala roadkill during an upgrade of the Pacific Highway at Lindsay’s cutting, Coffs Harbour New South Wales

Abstract

This 6-year study aimed to monitor a local koala population and koala protection/mitigation measures before, during and after a major upgrade to the Pacific Highway at Lindsay’s cutting near Coffs Harbour in northern coastal New South Wales. This represents the scale of the individual koala interacting with traffic on a primary road within a well-studied Local Government Area for koalas. We also collected records of koala road injury and death from local wildlife carers. The principal findings were that, before the upgrade or any mitigation provisions, koalas were regularly killed on this 1 km stretch of highway flanked by primary koala habitat (26 records 1991–97). Koala exclusion fences largely eliminated the roadkill here, but the benefits were highly localised. Koalas made occasional use of a wildlife underpass below the highway. Two problems were identified: a farm gate left open in the fence allowed koalas onto the highway, and koalas could walk around the fence ends onto the highway. On the positive side, we have shown the value of local-scale research and mitigation, such as koala exclusion fences, and the value of examining the koala population of the surrounding area to assess the effectiveness of this mitigation at a larger scale.

Roads and water availability influence the occurrence of koalas (Phascolarctos cinereus) in secondary habitat: a multiscale approach

“…Road mortality is a significant threat to wildlife populations (Fahrig and Rytwinski 2009) including koalas across their range (Lunney et al 2022a(Lunney et al , 2022bMelzer and Black 2022), with a reported 300 vehicle related deaths per year in South East Queensland alone (Dique et al 2003b;de Oliveira et al 2014). Major roads, with higher volumes and speeds of traffic can act as movement barriers, decreasing habitat connectivity and gene flow (Dudaniec et al 2013).…”

Using expert elicitation to identify effective combinations of management actions for koala conservation in different regional landscapes

“…Habitat restoration programs can be conducted at different scales, individually or collectively, and can be supported through local, state and commonwealth government initiatives or grants or philanthropic organisations. Disease and injury management has been largely taken up by local volunteer groups operating under licence from the NSW State government (Lunney et al 2022a). Vehicle strike hotspot management is the responsibility of the State government for highways, but the management of local and arterial roads falls to local councils.…”

Use of road underpasses by mammals and a monitor lizard in eastern Australia and consideration of the prey‐trap hypothesis

“…In Australia, wildlife road crossing structures are often installed for threatened species (e.g., Mansergh & Scotts, 1989). In eastern Australia, concern about the impacts of new roads on the threatened koala has been responsible for the installation of vast lengths of road‐side fencing and large numbers of underpasses (e.g., Lunney et al, 2022; Taylor & Goldingay, 2003). Our study provides some insight into the effectiveness of this strategy for the koala and other threatened species.…”