The 65-acre Seal Island National Wildlife Refuge is 21 miles off the coast of Rockland, Maine. The Navy used the island as a bombing target from the 1940s until the early 1960s.
Seal Island is managed in cooperation with National Audubon Society for colonial nesting seabirds, including Arctic and common terns, common eiders, double-crested and great cormorants, Leach’s storm-petrels, black guillemots, razorbills, and Atlantic puffins. National Audubon successfully reintroduced Atlantic puffins to the island by transporting chicks from Newfoundland, Canada. Seal Island also supports one of the largest tern colonies in the Gulf of Maine, supporting over 2,300 pairs of Arctic and common terns. Each year Audubon and Refuge biologists collect information on seabird populations, food habits, and productivity, and work to control predators such as great back-backed and herring gulls. In 2000, Seal Island was recognized as the largest gray seal pupping island in Maine. Harbor and gray seals are common on adjacent ledges and in surrounding waters throughout the year.
The island is closed to public access year round due to the presence of unexploded ordnance.