Table 1_Self-directed behavior reflects social stress in captive Asian elephants.docx

Self-directed behaviors (SDBs), such as scratching, self-grooming, and body shaking, have been widely used as indicators of anxiety and social stress in non-human primates. However, research focused on SDB outside the primate range is still in infancy. Expanding this topic to other species can support animal welfare assessments and enhance comparative social studies. This study investigates whether SDB levels can reflect the social stress experienced in Asian elephants (Elephas maximus). Using all-occurrences and focal sampling on four captive individuals, we compared post-conflict SDB levels in victims to their baseline levels. Furthermore, changes in group composition during the study allowed us to examine whether individual baseline SDBs varied with social stress, measured as victimization rates across settings. Finally, we assessed whether there was any relation between levels of SDBs and stereotypic behavior. Results showed an increase in SDB levels in the victims after aggression compared to baselines, especially for behaviors recorded as counts. An estimated 39.8% increase in expected SDB counts was associated with the post-conflict context (E = 0.335, p = 0.024). The SDBs that differed more prominently were touch mouth, head shake, dust bathing, and trunk curled inwards (p < 0.05). Regarding baselines, two individuals increased their basal SDB levels when their rates as victims were the highest, although only one reached marginal significance. An individual who was never recorded as the recipient of aggression revealed remarkably low SDB levels. This study identified specific SDBs induced by social stress in Asian elephants and suggests SDB as a potential good indicator of their wellbeing.自我导向行为（Self-directed behaviors，简称SDBs），如挠痒、自我理毛与身体抖动，已被广泛用作非人灵长类动物焦虑与社会应激的评价指标。然而，针对灵长类以外物种的SDB相关研究仍处于起步阶段。将该研究主题拓展至其他物种，有助于完善动物福利评估体系，推动比较社会研究的发展。本研究旨在探究SDB水平能否反映亚洲象（Elephas maximus）所承受的社会应激水平。本研究以4头圈养亚洲象为研究对象，采用全事件记录法与焦点取样法，将冲突后受害个体的SDB水平与其基础水平进行对比。此外，研究期间象群群体组成发生变化，使得我们得以检验个体基础SDB水平是否随社会应激水平变化——此处社会应激以不同情境下的受害率作为衡量指标。最后，本研究还评估了SDB水平与刻板行为之间是否存在关联。研究结果显示，与基础水平相比，冲突后受害个体的SDB水平显著上升，尤其在以计数方式记录的行为中表现更为明显。冲突后情境下，预期SDB计数量可提升39.8%（E=0.335，p=0.024）。变化最为显著的SDB包括触嘴、摇头、沙浴以及鼻卷曲向内（p<0.05）。就基础SDB水平而言，2头个体在受害率达到峰值时，其基础SDB水平有所上升，但仅1头个体的结果达到边缘显著性水平。从未被记录为攻击受者的1头个体，其SDB水平显著偏低。本研究明确了亚洲象中由社会应激诱发的特定SDB类型，并表明SDB可作为衡量其福利水平的潜在有效指标。