RZS NSW News

Digging up the dirt on soil odour: Exploiting a major nesting cue to reduce fox predation on turtle nests

In Australia, pressures on native freshwater turtles are high. In addition to habitat loss, road mortality, poaching for the pet trade, and disease, invasive predators are currently having a devastating impact on turtle populations. In some locations, nest predation by invasive red foxes results in consecutive years of virtually no turtle eggs hatching, leading to a declining and aging population. The use of camouflaging odours has reduced predation in other systems but has never been trialled for turtle conservation. If the cue used by foxes to find turtle nests can be replicated, this method may offer a novel solution for use by volunteer turtle groups throughout Australia. 

Freshwater turtle nests are difficult to find visually, but canids like the red fox rely predominately on scents while foraging. The first 1-3 days after nest construction have the highest risk of discovery and predation, but a nest that survives these early days is likely to survive to hatch. It has been suggested that dirt moved during nest construction plays a role in alerting predators to the location of nests. Whenever soil is disturbed, molecules of various chemicals are released into the air. By sampling odours emitted by turtle eggs, soil, and nests, I aim to develop a treatment that can camouflage olfactory cues at turtle nesting sites during these first few days, when predation risk is highest. If successful, this will provide a relatively low-cost, low effort, and non-lethal solution to protect turtle nests from predators.

Peregrin Reed, The University of Sydney

Peregrin Reed is a PhD student researcher at the University of Sydney in the Behavioural Ecology and Conservation Research Group. They are interested in non-lethal solutions to human-wildlife conflicts and their current research focuses on how sensory misinformation can be applied to aid turtle conservation. Peregrin completed a Master of Science in Biological Sciences at California State University, Long Beach where their research in the Mammal Lab focused on the urban ecology of a wild canid. Outside of academia, Peregrin has over 10 years of professional experience as a field technician in wildlife and fisheries for state, federal, and private organisations.