Bull Island or more properly North Bull Island is an island located in Dublin Bay lying roughly parallel to the shore off Clontarf (including Dollymount), Raheny, Kilbarrack, and facing Sutton. The island, with a sandy beach running its entire length, is a relatively recent, and inadvertent, result of human intervention in the bay.
The North Bull Island at present is 5km long and 800m wide, and the area above high tide is approximately 300 hectares. It contains a wide range of natural habitats which include intertidal mudflats, salt marsh, freshwater marsh, dunes, and beach area.
The mudflats support a large population of birds, at any time up to 27,000 birds are present, which gives the area the highest bird density in Ireland. Many of the birds are migratory and these wild fowl and waders visit the Island in such numbers that they bestow on the Island an importance recognised internationally. Examples of some commonly found species are:- Brent Geese, Curlew, Widgeon, Grey Plover, Knots, Redshank, Bar-tailed Godwits, Shoveler, Oyster Catchers, Shellduck and Dunlins.