Portsmouth Harbor and the mouth of the Piscataqua River are busy with boat traffic much of the year. The islands and ledges along the southern tip of Gerrish Island bring to mind Maine?s island-studded coast to the north.
This area is especially important for wintering water birds including Great Cormorants that have numbered over 350 at one time. Large numbers of Razorbills and Purple Sandpipers can be found here in winter as well.
The busy port of Portsmouth as well the Naval Base on nearby Seavey Island present hazards to bird life primarily from the potential of a petroleum spill into these waters.
This site can be viewed easily from the pier at Fort Foster (see previous site description for this IBA) as well as via the park road at Fort Foster.