Shiant Isles
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The Shiant Isles (Scottish Gaelic: Na h-Eileanan Mòra), also known in Gaelic as "The Enchanted Isles" (Na h-Eileanan Seunta) are a privately owned island group in the Minch, east of Harris in the Outer Hebrides of Scotland. They are five miles south east of Lewis.[1]
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[edit] Geography and geology
The main islands are Garbh Eilean and Eilean an T(a)ighe, which are joined by a narrow isthmus, and Eilean Mhuire.
The islands are known for their dolerite columns, similar to but much larger than those on Staffa, and they are surrounded by tall cliffs, which are over 400 ft/500m high.
In geological terms, these islands essentially represent an extension of the Trotternish peninsula of Skye. The rocks are volcanic, and at 60Ma, very young by Hebridean standards. Dolerite columns on the north side of Garbh Eilean are over 100m tall and about 2m across. Similar to those at Staffa and the Giant's Causeway, they were formed by the slow cooling of volcanic rocks deep underground.[2] Intrusion sills show a progression in their chemical compositions, from olivine-rich rocks at the base to rocks with very little or no olivine at the top. The sills are thought to have formed by crystal settling. Recent study has suggested that at least one of the sills represents a multiple intrusion.[3] In some places the basalt is overlain by Jurassic mudstone, which weathers to form much more fertile soil than elsewhere in the Western Isles.
[edit] History
At the turn of the 20th century, the Shiant Isles had a population of 8.[1]
The author and politician Compton MacKenzie owned the islands from 1925 until 1937. He was an island lover who, at different points in his life, also owned Barra in the southern Outer Hebrides, and rented Herm in the Channel Islands. He never lived on the Shiants, but paid several brief visits during his time as owner.[1]
In 1937 the islands were acquired by Nigel Nicolson, then an undergraduate at Oxford, who like MacKenzie was later a writer, publisher and politician. Nicolson's son, the writer Adam Nicolson, published the definitive book on the islands, Sea Room. The Shiants now belong to Adam's son Tom. Sheep belonging to a Lewis crofter graze all three islands. The simple bothy restored by Nigel Nicolson on Eilean an Taighe is currently the only habitable structure on the islands.[4]
[edit] Wildlife
The Shiant Isles have a large population of seabirds, including tens of thousands Atlantic Puffins breeding in burrows on the slopes of Garbh Eilean, as well as significant numbers of Common Guillemots, Razorbills, Northern Fulmars, Black-legged Kittiwakes, Common Shags, gulls and Great Skuas. Although St Kilda has more puffins, the sheer density on the Shiants is greater.[2][6]
The islands are also home to a colony of Black Rats, which may originally have come ashore from a shipwreck.[7] Apart from one or two small islands in the Firth of Forth, the Shiants are the only place in the UK where the black rat or ship's rat (Rattus rattus) can still be found.[8] There are thought to be about 3,000 rats on the islands. Analysis of their stomach contents has shown that the Shiant rats do eat seabirds, but it is impossible to tell if they prey on live birds or simply scavenge dead remains.[9] Their numbers are still controlled in and around the house. Elsewhere on the islands they are unmolested.[10]
[edit] Footnotes
- ^ a b c Keay, J. & Keay, J. (1994) Collins Encyclopaedia of Scotland. London. HarperCollins.
- ^ a b Western Isles Guide Book: Shiant Islands. Retrieved on 2007-07-21.
- ^ Kathryn Goodenough (September 1999). Geological Conservation Review: Shiant Isles SSSI. Scottish Natural Heritage. Retrieved on 2007-07-21.
- ^ Nicholson, Adam Sea Room: an island life Harper Collins, 2001 (ISBN 0-00-257164-1)
- ^ Harvie-Brown, J. A. & Buckley, T. E. (1889), A Vertebrate Fauna of the Outer Hebrides. Pub. David Douglas, Edinburgh. Facing P. XIV.
- ^ Birds of the Shiant Islands: 1970 & 1971 census. Shiant Islands. Retrieved on 2007-07-21.
- ^ Haswell-Smith, Hamish (2004) The Scottish Islands. Edinburgh. Canongate.
- ^ "Developing a mammal monitoring programme for the UK" (pdf). Joint Nature Conservation Committee. Retrieved on 2007-01-02.
- ^ Stapp, Paul (2002) "Stable isotopes reveal evidence of predation by ship rats on seabirds on the Shiant Islands". Scotland Journal of Applied Ecology 39 (5), 831–840.
- ^ A. Nicolson, personal comment.
[edit] Bibliography
- Nicolson, Adam (2001). Sea Room: an island life. Harper Collins. ISBN 0-00-257164-1.
- Benvie, Niall (2004). Scotland's Wildlife. Aurum Press. ISBN 1-85-410978-2.
[edit] External links
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