Our recent paper in Biological Conservation provides an eerie insight into the cryptic impacts of development in otherwise relatively intact landscapes. Aided by a crew of intrepid volunteers, I spent over a year and walked over 560 km, surveying the activity of three mammalian predators — dingoes, cats, and foxes — on and around unsealed vehicle tracks in the largest remaining temperate woodland on earth: the Great Western Woodlands. What I found was startling.
The Great Western Woodlands are largely wild and dominated by natural processes. However, a number of threats to this ecological jewel exist, including a vast network of roads and vehicle tracks supporting an active economy of mineral exploration and extraction. We captured images of our study predators by motion-sensor cameras, and collected scat and print observations as further evidence of their activity, to understand how the presence of roads and tracks affect their activity.
We found that predator activity was between 12 and 261 times greater on roads compared with off-road, making roads (even very simple bush tracks, composed of only two wheel ruts through vegetation) ‘highways’ of predator activity. We also found many other intriguing phenomena, including different patterns in different vegetation types and using different detection methods, and peaks in predator activity at substantial distances away from roads.
With predators having major influences on their prey as well as how ecosystems function in a wider sense, these findings indicate that even apparently minor disturbances can lead to major ecological changes. Furthermore, these trends are likely to apply to many other ecosystems around the world, with global ramifications. At the same time, having this knowledge can also help us to understand how to manage and mitigate these impacts better.
The paper is available for free till December 29th at: https://authors.elsevier.com/a/1Y1Mk1R~eAsRA.
So the next time someone you walk down a simple road through the bush… consider what else has walked that way too, and what it might have preyed upon along the way.
Thank you to my co-authors, who were also my PhD supervisors, for their incredible inspiration and support for this research, and the incredible field volunteers I recruited. A big thank you also to the funding agencies and organisations that helped make this work possible – they are detailed in the ‘acknowledgements’ section of the paper.