Native name: Cloch Dábhiolla Nickname: The Cow and The Calf | |
|---|---|
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  Rockabill | |
| Geography | |
| Location | Irish Sea |
| Coordinates | 53.°35.49′N6.°0.16′W / 53.59150°N 6.00267°W /53.59150; -6.00267 |
| Archipelago | Rockabill |
| Total islands | 2 (The Rock and The Bill) |
| Major islands | The Rock |
| Administration | |
| Province | Leinster |
| County | Dublin |
| Barony | Skerries |
| Demographics | |
| Population | 2, May through August[1] (2014) |
Rockabill (Irish:Cloch Dábhiolla)[2] is a close pair of islands (Rock and Bill) in the westernIrish Sea about 6 kilometres east-north-east ofSkerries, County Dublin,Ireland. The two granite islands are separated by a channel about 20 metres wide. On the Rock there is alighthouse, built 1855–1860 fromgranite andlimestone and automated in 1989, and several walls and outbuildings.
The walled areas of the Rock have enabled a build-up of soil and the establishment of vegetation, notably tree mallow (Malva arborea), which provides nesting cover for the birds. The Bill is smaller and has very little vegetation.
Rockabill is an importantseabird breeding island, especially notable for itsterns. It is an internationally important site forroseate terns, with the largest colony in Europe, 1,597 pairs, and 2,085 pairs of Common Terns (2017 data). Other seabirds includeblack guillemots andblack-legged kittiwakes. It has been designated anImportant Bird Area (IBA) byBirdLife International because of its seabird colonies.[3]
Rockabill Lighthouse is owned by theCommissioners of Irish Lights and is aRefuge for Fauna and aSpecial Protection Area under theEuropean Union Birds Directive. Since 1989, when the protection afforded by the lighthouse keepers ceased, the islands have been managed byBirdWatch Ireland.[4] The sea area between Rockabill andDalkey Island has recently been proposed as aSpecial Area of Conservation.[5]