Big and little Libby Islands are mostly treeless and lie in outer Machias Bay.
At one time, over 1500 Common Eiders nested on these islands. They are also especially important Herring Gull and Great Black-backed Gull nesting sites. Large numbers of Leach?s Storm-petrels are believed to nest here as well. Furthermore, the shoreline is especially good habitat for Black Guillemots. There has been a large population of resident Canada Geese nesting here in recent years.
An active aquaculture site is adjacent to these islands. It is not clear whether there is any effect on nesting or feeding seabirds. These islands are zoned as Significant Wildlife Habitat under Maine?s Natural Resources Protection Act.
Big Libby Island is owned by the Maine Dept. of Inland Fisheries and Wildlife, and managed as part of the Coast of Maine Wildlife Management Area. It was purchased with funds from the first state duck stamp print in 1984. The U. S. Fish and Wildlife Service assumed ownership of Little Libby Island when it took responsibility for the lighthouse there. Landing at either of the Libby Islands is restricted from April 1 through August 31.