Meeting Abstract
Short-term behavioral effects of early-life stressor experience and/or elevated glucocorticoids are widely documented across vertebrates. However, the persistence and severity of these effects are largely unknown, especially through the adult stage and in wild species. We investigated long-term effects of experimental post-natal increases in circulating corticosterone on antipredator behavior in house sparrows (Passer domesticus). We manipulated circulating corticosterone concentration in wild, free-living nestlings, transferred fledglings to captivity, and tested juveniles and adults for two measures of antipredator behavior: evasiveness during a direct human encounter, and propensity to escape from a risky environment. We found no effect of treatment on escape behavior, but a delayed effect on evasive behavior: treatment lowered evasive behavior in adults but not juveniles, and this effect was moderated by current body condition. These results highlight the importance of state-behavior interactions and life stage in assessing long-term effects of early-life stress, and provide rare evidence for delayed effects of early-life stress to adulthood.
