Background Considering animals as individuals and not as species is becoming increasingly essential to animal welfare management in captive settings. Recent studies on big cat personalities and coping strategies suggest personality can help big cats cope in their surroundings. Yet a large portion of the published literature focuses on understanding either the personality or stress physiology of big cats. Our research shows how integrating an improved understanding of the personality of big cats with stress physiology may enhance welfare, especially for endangered species like African lions. By using a wild cat personality checklist, this study compared the key personality dimensions of 22 African lions with its faecal glucocorticoids and assessed factors influencing their personality and stress physiology. Results We found two reliable personality dimensions for African lions (dominance and agreeableness) and identified key factors (sex, age and location) that may influence their personality. Further, on testing if these factors influenced the stress physiology through variations in glucocorticoid levels, there was no significant difference. However, there was a strong negative association between agreeableness and glucocorticoid levels. These results suggest that the behavioural traits loading positively and higher for agreeableness are associated with lower glucocorticoid stress levels, which may assist a lion to cope with stressors in its surroundings. Conclusions Our findings highlight this integrated approach of linking personality and stress physiology of big cats can be beneficial for caretakers. For example, during stressful veterinary procedures or in reintroduction programs, recognizing the personality of lions can help in designing or providing them with resources that will alleviate stress. Thus, there is a need for more interdisciplinary approaches that will contribute towards enhancing the individual and overall welfare of big cats.

Background: Considering animals as individuals and not as species is becoming increasingly essential to animal welfare management. Recent studies on big cat personalities and coping strategies suggest personality can help big cats cope in their surroundings. Yet, a large portion of the published literature focuses on understanding either the personality or stress physiology of big cats in isolation. Our research shows how integrating an improved understanding of the personality of big cats with stress physiology may enhance welfare, especially endangered species like African lions. By using a wild cat personality checklist, this study compared African lion personality with its faecal stress glucocorticoids non-invasively. Results: We identified three personality types for individual African lions (Dominance, Agreeableness and Neuroticism) and examined whether these dimensions varied with stress cortisol levels. When controlling for differences in age across lions, we found a strong negative correlation between Agreeableness in lions and their glucocorticoid levels. This suggests that the personality of a lion may help it cope with its surroundings. Conclusions: Our findings can assist with the better management of big cats and it is proposed that ex-situ managers of zoos and rescue centres incorporate the personality data of their animals into the Zoological Information Management Software (ZIMS). This data can be accessed globally and can be useful for caretakers managing their animals according to their needs while undergoing veterinary procedures or in reintroduction programs. Thus, by improving individual welfare, we can improve overall welfare of big cats.