http://www.arthritistreatmentcenter.com Stress May Lead to Better Bird Parenting
According to Science Daily, birds with high levels of stress hormones have the highest mating success and offer better parental care to their brood, according to new biology research at Queen’s University. “Having high levels of glucocorticoid or stress hormone is often thought to indicate an individual in poor condition who has a low level of mating success. However, our research indicates that tree swallows with the highest levels of stress hormone have the highest reproductive success,” says Frances Bonier who investigates the way animals cope with challenges in their environment. The researchers measured glucocorticoid levels in female tree swallows before and after experimentally changing their brood sizes. Females whose broods were enlarged by two nestlings nearly doubled their glucocorticoid levels, while the glucocorticoid levels of females whose broods were reduced remained unchanged. Females with greater increases in glucocorticoids also fed their nestlings at higher rates, suggesting that stress hormones facilitate parental behavior.