Case studies of motion-sensing cameras to study clutch survival and fate of real and artificial ground-nests in Australia

Abstract

ABSTRACTCapsule: Trail cameras monitoring clutches of ground-nesting birds in Australia revealed survival rates and new causes of egg loss. We also show that nests with artificial eggs versus real eggs do not reveal the same information on predators.Aims: We describe the application of trail cameras for monitoring real and artificial clutches of ground-nesting birds through a series of case studies. We rate the degree of inference used when defining nest outcomes and assigning fates.Methods: Four case studies are presented, based on 326 deployments of cameras on real and artificial nests.Results: The probability of hatching varied between species and populations (40.0–83.3% hatched), but not between urban and rural habitats. The ‘degree of inference’ scores did not differ between species and contexts. Two case studies which examined habitat-mediated survival (ecological hypotheses) found no difference in survival between urban and rural habitats, nor between open and covered microhabitats. Another case study (a management hypothesis) found that predator exclusion cages increased clutch survival even though predators sometimes breached the cages and cages altered the assemblage of predators visiting the area. A fourth study revealed that the assemblage of predators eating eggs differed between real and artificial nests.Conclusion: Cameras enabled the survival and fate of most nests to be determined.