Rockabill
Encyclopedia
Rockabill is a group of two islands, "The Rock" and "The Bill", lying in the western Irish Sea
about 6 kilometres east-north-east of Skerries
, County Dublin
, Ireland
. An alternative Irish name, Carraig Dhá Bheola, meaning Two Lips Rock, is probably just a corruption of Carraig Dábhiolla.
The two granite islands are separated by a channel about 20 metres wide. On the Rock there is a lighthouse
, built 1855–1860 from granite
and limestone
and automated in 1989, and several walls and outbuildings. These walled areas have enabled a build-up of soil and the establishment of vegetation, notably tree mallow (Lavatera arborea
), which provides nesting cover for the birds. The smaller Bill has very little vegetation.
Rockabill is an important seabird
breeding island, especially notable for its tern
s. It is an internationally important site for Roseate Tern
s, with the largest colony in Europe, over 600 pairs in 2003. There are similar numbers of Common Tern
s, and other seabirds include Black Guillemot
s and Black-legged Kittiwake
s.
Rockabill is owned by the Commissioners of Irish Lights
and is a Refuge for Fauna and a Special Protection Area
under the European Union
Birds Directive. Since 1989, when the protection afforded by the lighthouse keepers ceased, the islands have been managed by BirdWatch Ireland
.
Harbour Commissioners proposed that a lighthouse be built on Rockabill, with the costs to be paid by tolls on the shipping using Drogheda harbour. In 1838, Trinity House
, which was then in charge of lights in Ireland, declined the request. In 1853 however the Trinity Board reversed its decision and authorized the construction of the lighthouse. Construction began in 1855 under the supervision of the Burgess brothers, William and James, who were builders from Limerick
. The lighthouse tower was built of grante granite from the Mourne Mountains in County Down
and local limestone from Milverton
. The total cost of all buildings and equipment was £13,248. The light was placed into operation on 1st. July 1860.
The focal plane of the lantern is 45 metres (148 ft) above the sea. The round lighthouse tower is built of granite and is 32 metres (105 ft) high, including the lanternhouse and gallery. The light tower is painted white with one broad black horizontal band. In 1918, the station is also equipped with a fog horn. A keeper's residence and other buildings are located at the station, which is operated by the Commissioners of Irish Lights. The lighthouse was automated in March 1989.
Irish Sea
The Irish Sea separates the islands of Ireland and Great Britain. It is connected to the Celtic Sea in the south by St George's Channel, and to the Atlantic Ocean in the north by the North Channel. Anglesey is the largest island within the Irish Sea, followed by the Isle of Man...
about 6 kilometres east-north-east of Skerries
Skerries, Dublin
-The 20th century and today:Historically, Skerries has been a thriving fishing port and a major center of hand embroidery. In the late 20th century, it became a resort town , and another suburb for commuters to the city of Dublin....
, County Dublin
County Dublin
County Dublin is a county in Ireland. It is part of the Dublin Region and is also located in the province of Leinster. It is named after the city of Dublin which is the capital of Ireland. County Dublin was one of the first of the parts of Ireland to be shired by King John of England following the...
, Ireland
Ireland
Ireland is an island to the northwest of continental Europe. It is the third-largest island in Europe and the twentieth-largest island on Earth...
. An alternative Irish name, Carraig Dhá Bheola, meaning Two Lips Rock, is probably just a corruption of Carraig Dábhiolla.
The two granite islands are separated by a channel about 20 metres wide. On the Rock there is a lighthouse
Lighthouse
A lighthouse is a tower, building, or other type of structure designed to emit light from a system of lamps and lenses or, in older times, from a fire, and used as an aid to navigation for maritime pilots at sea or on inland waterways....
, built 1855–1860 from granite
Granite
Granite is a common and widely occurring type of intrusive, felsic, igneous rock. Granite usually has a medium- to coarse-grained texture. Occasionally some individual crystals are larger than the groundmass, in which case the texture is known as porphyritic. A granitic rock with a porphyritic...
and limestone
Limestone
Limestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate . Many limestones are composed from skeletal fragments of marine organisms such as coral or foraminifera....
and automated in 1989, and several walls and outbuildings. These walled areas have enabled a build-up of soil and the establishment of vegetation, notably tree mallow (Lavatera arborea
Lavatera arborea
Lavatera arborea , the Tree Mallow, is a species of mallow native to the coasts of western Europe and the Mediterranean region, from the British Isles south to Algeria and Libya, and east to Greece.- Description :It is a shrubby annual, biennial or perennial plant growing to 0.5–2 m tall...
), which provides nesting cover for the birds. The smaller Bill has very little vegetation.
Rockabill is an important seabird
Seabird
Seabirds are birds that have adapted to life within the marine environment. While seabirds vary greatly in lifestyle, behaviour and physiology, they often exhibit striking convergent evolution, as the same environmental problems and feeding niches have resulted in similar adaptations...
breeding island, especially notable for its tern
Tern
Terns are seabirds in the family Sternidae, previously considered a subfamily of the gull family Laridae . They form a lineage with the gulls and skimmers which in turn is related to skuas and auks...
s. It is an internationally important site for Roseate Tern
Roseate Tern
The Roseate Tern is a seabird of the tern family Sternidae. This bird has a number of geographical races, differing mainly in bill colour and minor plumage details....
s, with the largest colony in Europe, over 600 pairs in 2003. There are similar numbers of Common Tern
Common Tern
The Common Tern is a seabird of the tern family Sternidae. This bird has a circumpolar distribution, breeding in temperate and sub-Arctic regions of Europe, Asia and east and central North America. It is strongly migratory, wintering in coastal tropical and subtropical regions. It is sometimes...
s, and other seabirds include Black Guillemot
Black Guillemot
The Black Guillemot or Tystie is a medium-sized alcid.Adult birds have black bodies with a white wing patch, a thin dark bill, and red legs and feet. They show white wing linings in flight. In winter, the upperparts are pale grey and the underparts are white. The wings remain black with the large...
s and Black-legged Kittiwake
Black-legged Kittiwake
The Black-legged Kittiwake is a seabird species in the gull family Laridae.This species was first described by Linnaeus in his Systema naturae in 1758 as Larus tridactylus....
s.
Rockabill is owned by the Commissioners of Irish Lights
Commissioners of Irish Lights
The Commissioners of Irish Lights is the body that serves as the lighthouse authority for Ireland plus its adjacent seas and islands...
and is a Refuge for Fauna and a Special Protection Area
Special Protection Area
A Special Protection Area or SPA is a designation under the European Union Directive on the Conservation of Wild Birds.Under the Directive, Member States of the European Union have a duty to safeguard the habitats of migratory birds and certain particularly threatened birds.Together with Special...
under the European Union
European Union
The European Union is an economic and political union of 27 independent member states which are located primarily in Europe. The EU traces its origins from the European Coal and Steel Community and the European Economic Community , formed by six countries in 1958...
Birds Directive. Since 1989, when the protection afforded by the lighthouse keepers ceased, the islands have been managed by BirdWatch Ireland
BirdWatch Ireland
BirdWatch Ireland is the current name of the organisation that used to be known as the Irish Wildbird Conservancy.BirdWatch Ireland is the leading voluntary conservation organisation in the Republic of Ireland, devoted to the conservation and protection of the Republic of Ireland's wild birds and...
.
Lighthouse
In 1837 the DroghedaDrogheda
Drogheda is an industrial and port town in County Louth on the east coast of Ireland, 56 km north of Dublin. It is the last bridging point on the River Boyne before it enters the Irish Sea....
Harbour Commissioners proposed that a lighthouse be built on Rockabill, with the costs to be paid by tolls on the shipping using Drogheda harbour. In 1838, Trinity House
Trinity House
The Corporation of Trinity House of Deptford Strond is the official General Lighthouse Authority for England, Wales and other British territorial waters...
, which was then in charge of lights in Ireland, declined the request. In 1853 however the Trinity Board reversed its decision and authorized the construction of the lighthouse. Construction began in 1855 under the supervision of the Burgess brothers, William and James, who were builders from Limerick
Limerick
Limerick is the third largest city in the Republic of Ireland, and the principal city of County Limerick and Ireland's Mid-West Region. It is the fifth most populous city in all of Ireland. When taking the extra-municipal suburbs into account, Limerick is the third largest conurbation in the...
. The lighthouse tower was built of grante granite from the Mourne Mountains in County Down
County Down
-Cities:*Belfast *Newry -Large towns:*Dundonald*Newtownards*Bangor-Medium towns:...
and local limestone from Milverton
Milverton
Milverton is the name of several places, each deriving its name from the county of Somerset:-People:*Arthur Richards, 1st Baron Milverton*Charles Augustus Milverton, fictional character in The Adventure of Charles Augustus Milverton by Arthur Conan Doyle...
. The total cost of all buildings and equipment was £13,248. The light was placed into operation on 1st. July 1860.
The focal plane of the lantern is 45 metres (148 ft) above the sea. The round lighthouse tower is built of granite and is 32 metres (105 ft) high, including the lanternhouse and gallery. The light tower is painted white with one broad black horizontal band. In 1918, the station is also equipped with a fog horn. A keeper's residence and other buildings are located at the station, which is operated by the Commissioners of Irish Lights. The lighthouse was automated in March 1989.