This video adapted from KTOO examines a virus outbreak that affected the Pacific herring population in Alaska's Prince William Sound in 1999. Because the herring play a very important part in both the local economy and the subsistence lifestyle practiced by the area's Alaska Native people, community members and scientists have sought to identify the cause of the virus. One hypothesis suggests that oil from the 1989 Exxon Valdez tanker spill, though not the direct cause of the virus, is a stressor that allowed the virus to take hold in the fish 10 years after the spill.