Island 221 - White Island, St Martins, Isles of Scilly

White Island (apparently it is pronounced wit, not white)is located about 200 metres off the north coast of St Martin's.  It is approximately 800 metres from north to south.  It is 400 metres wide at its nearest point but only 75 metres at its narrowest and has an area of around 165 hectares.   The highest point on the island is 31 metres above sea level.  There is a coast path around the island but on the west coast much of it has disappeared into the sea quite recently by the look of it.  The island can be accessed at least 2 hours either side of low tide across a beach of sand and boulders.   It is currently uninhabited.

White Island is an SSSI, which is managed by the Isles of Scilly Wildlife Trust on behalf of the Duchy of Cornwall.  It is a breeding location for lesser black backed, herring and greater black backed gulls, kittiwakes and fulmars. When I visited in mid March there were lots of gulls on the maritime heath in the middle of the island.  They got a bit agitated by my presence, so I tried to keep to the coast as far as possible and didn't stay long.  

The island's thin soils and its exposed position have led to the development of wind pruned waved maritime heath, which is dominated by heather and gorse.  There are also areas of maritime grassland and lots of thrift.   The more sheltered areas, which have thicker soil, are covered in bracken and brambles and some honeysuckle.

The geo that almost cuts White Island in two is called Chad Girt.  It is of great interest to geologists, as it has an unusual sequence of late Pleistocene deposits.  These are a raised beach, granitic head (Porthloo Breccia), soliflucted material containing glacially derived clasts and loess (Hell Bay Gravel), head containing erratics (Brad and Cheese Breccia).

The remains of a kelp pit, which was used to burn the seaweed to produce soda ash from the 17th to the mid-19th centuries, is located on the west side of White Island.


North end of White Island



White Island Geo - Chad Girt
 - this nearly cuts the island in half

White Island from St Martin's 

North end of White Island
Lots of thrift plants, not in flower in mid March

White Island - Porth Morran
Centre of the island looking south west towards St Martin's across the waved maritime heath.

This is in the vicinity of the chambered cairn marked on the OS map, which I couldn't find.  It think these rocks may be the remains of an ancient field system.  There are several other ancient cairns on the island.

White Island's only tree

Looking towards Chapel Down on St Martin's from White Island

White Island from St Martin's 

Porth Morran looking north


Porth Morran looking south