Project OZscav hits the Big Red: a successful first field season at Ethabuka, in the Simpson Desert

This field trip served as the debut to major carrion ecology research in the Simpson Desert. It also began the first field season of the NESP (TSR Hub) funded project investigating the potential impacts of carrion on ground nesting birds such as the night parrot (Pezoporus occidentalis), in Australian arid environments. Built as a collaboration between the University of Sydney, the University of Queensland and Bush Herritage Australia (BHA), this study is broader than just carrion, predators and prey; it also explores the use of carrion by insects, and will develop understanding on the flow-on impacts of this resource to surrounding soil and plant communities.

Volunteer Gill and his photoshoot with a potential carrion scavenger, the brown falcon (Falco berigora; Photo credit: Emma Spencer)

Overall, the first field season went very well, with 20 carcass sites established. At each of these sites, plant surveys were conducted and soil samples collected to provide baseline “before carrion” data. Motion sensor cameras were positioned to monitor vertebrate scavenger and predator use of carcasses and insect pitfall traps were also dug into the ground to enable detection of ants, flies and beetles using the resource. In addition to the animal, soil and plant monitoring, artificial “fake” nests were constructed in the sand at various distances surrounding each carcass to determine whether proximity to carrion influences nest predation.

Emma setting up a motion-sensor camera to monitor a carcass positioned on a sand dune crest (Photo credit: Thomas Newsome)
Tom setting up a motion-sensor camera to monitor predation on an artificial “fake” nest (Photo credit: Emma Spencer)

While results are still incoming, and images, soil samples and insect traps are yet to be sorted, identified and analysed, the camera images have shown a great deal of activity on the carcasses thus far. Wedge-tailed eagles, ravens and red foxes are dominant on many carcasses and dingoes and feral cats are also making an appearance. Ravens and foxes have dominated nest predation and there appears to be a clear negative impact of the presence of carrion on nest predation.

A motion-sensor camera image showing five wedge-tailed eagles (Aquila audax) feeding on a kangaroo carcass at Ethabuka
A motion-sensor camera image showing a feral cat feeding on a carcass, under the watchful eye of a corvid
A red fox captured by a motion-sensor camera removing an egg from a “fake” nest

This work will be repeated in September/October of this year (2018), with a few additions to the method. For example, further work involving the remains of camels may be incorporated and a camel carcass is currently being monitored on site as a “pilot” to this work. Indeed, reducing feral camel numbers via culling is a key management concern for BHA, but they are also determined to assess potential impacts of such consistent (and potentially broader-scale) culls on the surrounding environment.

“Culled” camel carcass monitored by a remote camera at Ethabuka (Photo credit: Thomas Newsome)