Seal Island, located in Prince William Sound, is an uninhabited and forested landmass approximately 0.5 miles (0.8 km) across, about 7 miles (11 km) east of Knight Island and 58 miles (93 km) west-southwest of Cordova, Alaska. The U.S. Coast and Geodetic Survey first published its name in 1899. Presumably named for the common harbor seal, Seal Island is associated with the species that is the most widely distributed pinniped in coastal waters. Historically, harbor seals were a staple in the diet of the Alutiiq Sugpiat peoples from the villages of Tatitlek, Chenega Bay, Eyak, and Nuchek.

The Exxon Valdez oil spill in March 1989 was one of the most devastating environmental disasters in U.S. history, and Seal Island in Prince William Sound was among the most severely affected areas. In the months following the spill, field reports highlighted the dire situation on the island, where large quantities of oil had accumulated. By July 1989, the oil had formed deep pools and greasy brown emulsions, creating an ongoing environmental challenge as tides continually washed the oil back into the surrounding waters. To address this persistent problem, the U.S. Coast Guard implemented a rigorous cleanup operation. This effort involved removing as much of the stranded oil as possible from the shoreline to prevent further contamination of the water. The cleanup process was followed by bioremediation, a method that uses microorganisms to break down and degrade the remaining oil. This approach aimed to accelerate the natural decomposition of the oil, helping to restore the affected ecosystems over time. The efforts on Seal Island were part of a broader response to the Exxon Valdez spill, which included various cleanup techniques and innovations to mitigate the environmental impact and prevent similar disasters in the future.

Seal Island hosts a weather station that transmits data as part of the Hydrometeorological Automated Data System. This network of real-time data acquisition stations is operated and distributed by the National Weather Service. The weather station includes a precipitation gauge, part of the Natural Resources Conservation Service’s snow telemetry system. The Prince William Sound network comprises seven precipitation stations: Esther Island, Tatitlek, Mount Eyak, Strawberry Reef, Nuchek, Port San Juan, and Seal Island. These stations provide essential data for more accurate weather forecasts and ocean circulation modeling. Read more here and here. Explore more of Seal Island and Prince William Sound here: