Spatio-temporal analysis of kangaroo–vehicle collisions in Canberra, Australia

Over the last 30 years, there has been a steady increase in the number of kangaroo–vehicle collisions in Canberra, in the Australian Capital Territory (ACT), especially of the Eastern Grey Kangaroo (Macropus giganteus). Motor vehicle collisions with kangaroos are a threat to people and kangaroos, causing not only costly vehicle damage but also potentially leading to injury or loss of human life as well as animal welfare issues. Species, sex, moonlight, season and rainfall have previously been noted as potential influences on the number and frequency of kangaroo–vehicle collisions. In December 2015, a smartphone application using Collector for ESRI ArcGIS was implemented to enable ACT rangers to collect accurate information about each call-out or carcass attendance in real time. A total of 3346 kangaroo–vehicle collision points were collected by rangers over a 15-month period from March 2016 to June 2017. The data lend limited support to a concentration of kangaroo–vehicle collisions around the full moon, although 45% of collisions were recorded when the moon was less than 50% illuminated. Although the highest roadkill numbers were recorded in winter (June-August), kangaroo–vehicle collisions were not directly correlated with season: there is a complex interaction with other variables. This study revealed that the relationship between the movement between patches of habitat and roads is dynamic and that further research is warranted into potential methods for reducing the number of kangaroo–vehicle collisions on Canberra roads, particularly in relation to speed limits, seasonality and kangaroo movements proximate to roads and areas of core habitat.