Non-lethal predator impact mitigation: can we induce conditioned taste aversion in red foxes and ravens to chicken eggs using synthetic bush stone-curlew scent?
Here we describe the analyses conducted for Ellie Lambden's honours thesis: "Non-lethal predator impact mitigation: can we induce conditioned taste aversion in red foxes and ravens to chicken eggs using synthetic bush stone-curlew scent?".
Red foxes have horrifically destructive effects across Australia, however current management works against evolution since baiting and culling select for individuals who are best adapted to avoid our efforts. As such, these traits are enhanced with each generation, thus exacerbating the problem in the long term.
Conditioned taste aversion (CTA) harnesses evolution to select for traits we consider favourable - such as the avoidance of native prey. Although there are many successful studies showing the effectiveness of CTA as a concept, further studies are needed before it can be used as a management technique. For instance, while bush stone-curlew (BSC) eggs are targeted, they cannot be directly used in treatment because of their scarcity - it would be counterproductive to have to use the target species in management itself as it would inevitably result in population losses.
Here we aimed to use a synthetic odour that replicates the scent from real BSCs in the Ginninderry Conservation Corridor so problemtic predators would learn to the odour without compromising real eggs. We targetted two nest predators (foxes and ravens), and asked whether CTA could be induced in ravens when only 50% of baits are toxic, and whether BSC-specific CTA could be induced in foxes. These results will have wide implications for effective invasive and threatened species management.