The U. S. Fish and Wildlife Service acquired this 43-acre island in 1998. The island is primarily covered with low grasses and forbs with a few patches of woody shrubs. The perimeter of the island is granite ledge, ranging from gradual slopes to steep cliff.
Both the sizes of the colonies and the diversity of species make John?s Island unique. Nesting species include Common Eider, Great Black-backed and Herring Gulls, Black Guillemot, Double-crested Cormorant, and Great Cormorant. The island is also a harbor seal pupping area.
This island is difficult to access because of its rough shoreline and exposed location. This lessens the potential threats to the island. The potential for a hazardous spill or the problems associated with ballast discharge from the large number of cruise ships and Canadian-bound tankers that pass by the island all year pose a potentially serious threat.
The island has full conservation protection and is administered by the U. S. Fish and Wildlife Service, Maine Coastal Islands National Wildlife Refuge. It is closed to public access during the seabird nesting season (April 1 ? August 31).