Assessing capture and tagging methods for brolgas, Antigone rubicunda (Gruidae)

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Context Studies assessing welfare issues and efficiency of animal capture methods are important, as capture can pose a significant welfare risk and methods can be time consuming to develop. It is imperative to choose methods that minimise injuries, maximise capture rates and minimise time spent on capture. Aims To test methods of crane capture and tagging (transmitter, colour and metal band fitting), and to compare and develop safe and time efficient methods for capturing brolgas (Antigone rubicunda). Methods We tested three types of noose traps, cannon nets, clap-nets, spotlighting at night roosts and active pursuit of pre-fledged chicks. We also tested two band sizes and two transmitter attachment methods. We compared the success and capture efficiency of these methods and considered welfare issues by comparing the number of injuries and mortalities resulting from these methods. Key results We successfully captured brolgas with noose traps and a cannon net, and by using active pursuit of pre-fledged chicks. Noose traps became more efficient when deployed with call playback and taxidermy decoys. Australian noose traps and active pursuit of pre-fledged chicks were the safest methods with fewest injuries. Conclusions For maximum capture success with minimum injuries to target and non-target species, we recommend noose traps with call playback and taxidermy decoys for capturing adult and juvenile brolgas at feeding areas, and active pursuit for pre-fledged chicks at breeding sites. Noose lines should have elastic at both pegged ends, to avoid injuries. To minimise injuries from tagging, we recommend leg-band-fitted transmitters in preference to harness-fitted transmitters, Australian size 35 bands and colour bands with an internal diameter of 22 mm. Implications The use of Australian noose traps with call playback and taxidermy decoys is a safe and time efficient method for capturing brolgas, and is also likely to work for other crane species. Our recommendations can help reduce capture-related mortalities and injuries to brolgas (and potentially other cranes), which is crucial, given the brolga is a threatened species.