Exploring Personality Traits Associated with Reproductive Success in Captive Female Alpine Musk Deer (Moschus chrysogaster)

Animal personalities, reflecting consistent individual behavioral differences, are increasingly recognized as key factors influencing fitness. However, their role in the reproductive success of endangered ungulates remains poorly understood. In this study, 17 personality traits, including “Clumsy”, “Dominant”, “Vigilant”, “Affiliative” and so on, were assessed in 123 adult female captive Alpine musk deer (Moschus chrysogaster) using a scale-based personality rating method. We explored the relationships between these personality traits and reproductive fitness indicators, including litter size, calving success, and fawn mortality. Our exploratory analyses revealed that “Clumsy” scores were significantly higher in females that experienced calving failure (miscarriage or dystocia) compared to those that successfully gave birth (p = 0.013, Cohen’s d = 0.88), indicating a large effect size. However, no traits were correlated with litter size. For fawn mortality, although initial correlation analyses suggested associations with “Vigilant” and “Affiliative”, these were not supported when a Poisson regression model—appropriate for count data—was applied with litter size as an offset (model p = 0.092; all predictors p > 0.05). These findings suggest that the previously observed associations between maternal personality and fawn mortality may have been influenced by the use of an inappropriate statistical model. Overall, our study highlights the importance of using distribution-appropriate models for count-based fitness data and provides exploratory, hypothesis-generating evidence that, while “Clumsy” may be robustly associated with calving success (large effect size), personality–fitness relationships in this species require further validation with larger samples and across different captive populations.