Plastic debris is choking our ocean ecosystems, including the Bering Sea. In this region, the seabirds and their prey mistake plastics for food, resulting in exposure to harmful plastic-associated chemicals like phthalates. We do not know the extent of phthalate exposure nor their effects on seabird health. We aim to build knowledge of phthalate exposure in Bering Sea seabirds to understand effects on reproduction, survival, and ecosystem health.