Koala road kills are linked to landscape attributes on Central Queensland's Peak Downs Highway

Koala (Phascolarctos cinereus) road kills occur frequently along the Peak Downs highway through the Clarke-Connors ranges. Highway upgrades allowed mitigation of koala-vehicle collision frequency while maintaining koala population connectivity. This project aimed to understand road kill distribution to inform protective infrastructure investment. Koala road kills were associated with: (1) streams and associated alluvia where the dominant vegetation included Eucalyptus tereticornis and E. platyphylla; (2) ridges supporting E. drepanophylla open forest/woodland abutting streams or alluvia; and (3) mid-lower slopes, dominated by E. drepanophylla that were dissected by minor streams fringed by E. tereticornis ± E. platyphylla. Road kills did not occur in E. drepanophylla open forest/woodland on ridge upper slopes, crests or on hills, although koalas occur in this landscape. Explaining why koala road kills are linked to landscape features requires investigation. It is likely that: (1) landscape elements associated with drainage lines, alluvia and E. tereticornis support a relatively high koala abundance, and hence the road kill risk is correspondingly higher; and (2) the engineered road architecture and road verge characteristics in these landscape elements are conducive to koalas crossing the road.