57.6 Saturday, Jan. 5 Turning shy on winter’s day: effects of season on personality and stress response in Microtus arvalis GRACCEVA, G*; HERDE, A; KOOLHAAS, JM; PALME, R; ECCARD, JA; GROOTHUIS, TGG; Institute of Behavioural Neurosciences, University of Groningen; University of Potsdam; University of Groningen; University of Veterinary Medicine, Vienna; University of Potsdam; University of Groningen firstname.lastname@example.org
Many animals of temperate environments have evolved physiological and behavioural adaptations to cope with the cyclic seasonal changes. This may result in changes in personality: suites of behavioural and physiological traits that vary consistently amongst individuals. Winter, typically the adverse season challenging survival, may require individuals to have shy/cautious personality whether during summer, energetically favorable to reproduction and survival, individuals may benefit from a bold/risk taking personality. In order to test the effects of seasonal changes in early life and in adulthood on behaviour, body mass and stress response, we have manipulated the photoperiod and quality of food in two experiments to simulate the conditions of winter and summer. We used Microtus arvalis as they have been shown to display personality based on behavioural consistency over time and context. In both experiments we tested the voles for activity, exploration and risk-taking behaviours. Summer-born voles allocated to winter conditions at weaning had lower body mass, a higher corticosterone elevation after stress and a less active, more cautious behavioural phenotype in adulthood compared to voles born in and allocated to summer conditions. Behavioural consistency over time and context was unaffected. By contrast, adult females only showed plasticity in corticosterone-induced stress levels, which were higher in the animals placed in the winter condition than to those staying in summer conditions. These results suggest a sensitive period for season related plasticity of personality in which juveniles shift over the bold-shy axis as expected.