Cathryn Dexter

Cathryn Dexter

Abstract | Do hot spots go cold? What does this mean for species conservation long-term?

Wildlife road hot spots are commonly used to determine where mitigation treatments are best placed to reduce wildlife vehicle-strike, generally for a target species. A fundamental limitation with this approach is that long-term term data sets for road-kill are rare, therefore data used to make key management decisions are frequently based on relatively short-term assessments of a problem road or area. Equally, while the issue of wildlife road kill and hot spots is a common topic amongst authors, there appears to be no standardised methodology for what qualifies as a hot spot. This has potential implications for conservation managers as what appears to be a hot spot at one point in time, may in fact become a cold spot over time. Therefore, broader long-term conservation matters need to be considered before applying a mitigation treatment.

We analysed 15 years of koala road-kill data to determine if we could quantitatively identify the locations of koala road-strike hot spots in south-east Queensland overtime. A number of approaches to identifying hot spots were attempted and rejected as the complexity in qualifying a hot spot ‘in-time’ became clearer.

This work highlighted there is no one optimal approach to deriving hot spots and that this area of research needs more detailed attention. It also emphasised that by simply deriving hot spots and implementing a mitigation treatment does not necessarily reduce the long-term effects of roads on target wildlife.

This work urges researchers and managers to re-examine how hot spots are determined and viewed as a conservation tool, as there are numerous broader and longer-term considerations that should be taken into account prior to the installation of expensive mitigation infrastructure.

Bio | Cathryn Dexter

Cathryn Dexter is an ecologist and conservation biologist with a background in road ecology research, with a particular emphasis on koala movement. She is also a PhD candidate with Griffith University Environmental Futures Research Institute, Applied Road Ecology Group in Queensland. Cathryn has over 10 years’ experience as a researcher and project manager and has worked on major linear infrastructure projects for clients such as environmental consultancies and both State and Local government. Major projects include SEQ Koala Retrofit Works Program, Gap Creek Road upgrade, the Gateway Motorway upgrade, the Darra to Springfield Transport Corridor, and the Moreton Bay Rail Link (Redcliffe Peninsula line). Cathryn’s current role is with the Redland City Council in Queensland as a koala conservation officer. Cathryn is a founding and current committee member for the Australasian Network for Ecology and Transportation conferences.