LAUSR

Abstract Animal personality, the consistent between-individual differences in e.g., risk-taking, exploration, antipredator or mating behaviours, has major impacts on the fitness of individuals in many species. Understanding how to quantify animal personality should help us predicting how species interact with their environment and with the current environmental changes. We adapted existing behavioural assays to quantify the personality of two Brazilian tortoises, Chelonoidis carbonarius and C. denticulatus. We recorded behavioural responses to stress, novel environments, novel objects and social encounters. Behavioural components were consistent through time, supporting the existence of personality in both species. These behaviours were further correlated and could be summarized into two behavioural axes with recognizable biological meanings. One axis was related to responses to threats and novelty, as well as interest and interaction behaviours towards conspecifics and one to submission. The behavioural dimensions were similar in both species, suggesting that they share the same behavioural syndromes, but C. carbonarius had greater frequency of risk taking behaviours. This pattern can be related to differences in resource availabilities and predator pressures in their respective natural habitats. Within each species, however, the individual variation in morphology only had a weak effect on personality and males tended to show more signs of submission. Further studies are needed to investigate the role of habitat features (resource availabilities and predation risk) on individual behavioural variation in each species in order to improve conservation and translocations programs.