A novel method for the efficient capture of ground-nesting parent birds

In avian ecological and behavioral research, the live capture of adult birds is important for obtaining individual tagging data. However, traditional capture techniques have various limitations, such as efficiency, cost or ethical issues. In this study, we propose a modified cage trapping method based on the treadle cage design used in the traditional bird trapping culture of Guizhou, southwest China. By replacing food with 8- to 10-day-old nestlings as bait, this method exploits brooding behaviors to achieve the efficient and low-injury capture of adult birds. When an adult bird enters the cage, it comes in contact with the treadle, which triggers a mechanism to close the cage door. This method can be rapidly deployed near ground nests. From March to August 2024, four ground-nesting bird species with bi-parental care, the Grey bushchat (Saxicola ferreus), Yellow-throated bunting (Emberiza elegans), South rock bunting (Emberiza yunnanensis) and Verditer flycatcher (Eumyias thalassinus), were successfully captured as adults during field trials in Liuzhi, Guizhou and Lincang, Yunnan, southwest China. We obtained a capture rate of 100%, with no injury to adults or nestlings and no nest abandonment. Our findings demonstrate that this method effectively utilizes nestling begging and adult brooding behaviors for the efficient capture of target species, while considering animal welfare. Hence, this method can provide effective technical support for bird tracking and research in avian behavior, ecology, evolution and other fields.