Bull Island (Irish: Oileán an Tairbh), more properly North Bull Island (Irish: Oileán an Tairbh Thuaidh), is an island located in Dublin Bay in Ireland, about 5 km long and 800 m wide, lying roughly parallel to the shore off Clontarf (including Dollymount), Raheny, Kilbarrack, and facing Sutton. The island, with a sandy beach known as Dollymount Strand running its entire length, is a relatively recent, and inadvertent, result of human intervention in the bay. The island lies within the jurisdiction of, and is mostly owned by, Dublin City Council, and is managed by the Council's Parks and Landscape Division. Bull Island, which is accessed by way of a causeway bridge from Raheny and a wooden bridge from Clontarf, has the most designations of any site in the country, as a National Bird Sanctuary, a biosphere reserve, a National Nature Reserve, a Special Protection Area under the EU Birds Directive, and a Special Area of Conservation under the EU Habitats Directive, while also being the subject of a Special Amenity Area Order. It is a car-free zone. It holds a wide variety of plant and bird species, and a limited range of mammals, one reptile, one amphibian and a modest range of invertebrates; one mammal species, the hare, became extinct in the later 2010s. History Background In times past, Dublin Bay had a long-running problem with silting, notably at the mouth of the River Liffey. After years of primitive dredging, an attempt to maintain a clear channel more effectively was begun when, in 1715, the first piles were driven of what was to become the Great South Wall, completed in 1730. This barrier was breached by storm action some years later, and in 1761, a stone pier was commenced, working from the Poolbeg Lighthouse (1768), back to shore, the construction of massive granite blocks being completed in 1795. It was during this period that the building of a North Bull Wall was also proposed, and when it was seen that the South Wall did not solve the silting problem, the authorities responsible for Dublin Port commissioned studies on the matter. Captain William Bligh, of Bounty fame, surveyed Dublin Bay for the Ballast Board in 1801, highlighting the potential of the North Bull sandbank. Its purpose was to clear a sandbar by Venturi action. Bull Bridge, North Bull Wall and the beginning of Bull Island A wooden bridge, the first Bull