| Seabird parental care is thought to influence reproductive success, and the associated behaviors of parental care are linked to the ability to forage in an unpredictable marine environment. Therefore, parental care behaviors and reproductive success in seabirds might be useful indicators of changes in the marine environment. At Castle Rock National Wildlife Refuge we quantified parental care behaviors of Brandt's Cormorants, including nest-attendance and chick provisioning, to test whether parental care predicts reproductive success. Additionally, we examined interannual variation of reproductive success. We used a logistic exposure model to estimate daily survival rates (DSR). Given cormorants' life history traits and parental effort, the proportion of chicks that successfully fledge could be more informative than defining nest success as at least one chick fledging. Therefore, we estimated DSR for each chick, as opposed to each nest. Parental care behaviors and their relationship to chick survival may provide a stronger causal link between seabirds' reproductive success and the marine environment, allowing for better informed management and facilitate more accurate monitoring tools. |