Context: Helicopter darting has been used to capture wild deer, but this method has never been used for chital deer (Axis axis).

Aim: The aims of this study were to develop, assess and refine a helicopter darting technique for wild chital deer in northern Australia by quantifying: (1) reliable pharmacological doses for immobilisation; (2) the efficacy of the technique (including the duration of procedures); and (3) the frequency of adverse animal welfare events.

Methods: The study was conducted in three stages: an initial protocol (n = 25 deer captured) in July−August 2018; a refined second protocol implemented in June 2019 (n = 12 deer captured); and a further refined third protocol implemented in June 2019 (n = 12 deer captured). Parameters to estimate the duration of procedures were measured and the frequency of several adverse animal welfare events during capture were quantified: mortality (at the time of capture and within 14 days of capture), hyperthermia, hypoxaemia, dart inaccuracy and manual restraint. Finally, GPS location collars with a mortality-sensing function were used to monitor post-release mortality.

Results: Mortality within 14 days of capture was 40% for the first stage, 25% for the second stage and 17% for the third stage. Considerable refinement of procedures occurred between stages in consultation with an Animal Ethics Committee. One-third of all 15 mortalities occurred at the time of capture and were attributed to ballistic trauma from dart impact and acute capture myopathy. The majority (n = 10) of mortalities, however, occurred post-release and were only detected by mortality-sensing GPS location collars. These post-release mortalities were attributed to capture myopathy.

Conclusions: Helicopter darting of wild chital deer poses animal welfare risks, but these can be minimised through the selection of the most appropriate pharmacological agents and attempts at preventing factors such as hyperthermia and hypoxaemia that contribute to the development of capture myopathy. Further research into capture protocols is needed for helicopter-based immobilisation of chital deer. Fitting animals with GPS location collars enabled post-release mortality, which was significant, to be evaluated.

背景：直升机飞镖曾被用来捕获野鹿，但这种方法从未被用于野鹿（轴心轴）。

目的：本研究的目的是通过量化：（1）用于固定化的可靠药理剂量；开发，评估和完善澳大利亚北部野生野鹿的直升飞机飞镖技术。（2）该技术的功效（包括程序的持续时间）；（3）不利动物​​福利事件的发生频率。

方法：该研究分三个阶段进行：初始方案（n  = 25头鹿）于2018年7月至2018年8月进行；于2019年6月实施的完善第二议定书（ 捕获的n = 12头鹿）; 和在2019年6月实现的进一步细化第三协议（Ñ  = 12鹿捕获）。测量了估计手术时间的参数，并对捕获过程中若干不利的动物福利事件的发生频率进行了量化：死亡率（捕获时和捕获后14天内），体温过高，低氧血症，落镖误差和手动约束。最后，具有死亡率感应功能的GPS定位项圈用于监测释放后的死亡率。

结果：捕获后14天内的死亡率第一阶段为40％，第二阶段为25％，第三阶段为17％。在与动物伦理委员会协商后，各阶段之间的程序进行了相当大的改进。在所有15种死亡中，有三分之一发生在捕捉之时，并归因于飞镖撞击和急性捕捉肌病引起的弹道创伤。然而，大多数（n  = 10）的死亡发生在释放后，并且仅通过可感知死亡率的GPS定位项圈检测到。这些释放后的死亡率归因于捕获肌病。

结论：野生奇异鹿的直升飞机带来动物福利风险，但可以通过选择最合适的药理剂并尝试预防有助于捕获性肌病发展的因素（例如高热和低氧血症）来将这些风险最小化。对于基于直升机的小鹿固定化，需要对捕获方案进行进一步的研究。给动物安装GPS定位项圈可以评估释放后的死亡率，这一点值得评估。