We have found that seabirds get stressed during the breeding season, just like any other busy parent with too much work to do. We can measure stress by taking a small sample of blood from adults and measuring the concentration of corticosteroid stress hormone in the blood. Results from studies on Common Murres at two colonies in Cook Inlet show that stress levels vary among colonies and between years-- partially because of variability in food supplies. In 1997, murres at both colonies showed low levels of stress during the egg-laying and incubation phases of breeding. But as chicks hatched and demanded to be fed, the adults had to work harder to find and retrieve food for chicks. This led to a late-season increase in stress. In 1998, food was abundant around Gull Island, and the birds there had no apparent difficulty in feeding their chicks as stress levels remained similar all summer. At Chisik Island, however, food supplies were poor all summer. Adult murres were already highly stressed when they showed up to lay eggs in Spring, and stress levels remained high all summer. In fact, these birds failed to successfully rear any chicks that summer.