Dorset Coast: Isle of Portland to Studland Cliffs IPA
Location: Coast between Portland and Swanage, Dorset, south of the A351, 352 & 353.
Grid Reference: SY 813 801
Forming part of world famous Jurassic Coast, the meeting of land and sea along this stretch of Dorset is home to an exceptional diversity of plants, lichens and seaweeds. From colossal limestone cliffs to acidic sand dunes and into the sea itself, this is possibly the richest part of Britain for plants.
This Important Plant Area is home to:
• An exceptional diversity of mosses and liverworts growing in dry limestone grassland
• An exceptional diversity of lichens growing on acidic coastal sand dunes
• An exceptional diversity of seaweeds growing on intertidal rocks and offshore rocks
• An exceptional diversity of vascular plants growing on rocky cliffs ledges, shores and coastal shingle habitats
The Dorset coast here is a string of famous landmarks, from Swanage Bay in the east, through Kimmeridge Bay to Lulworth Cove and Durdle Door, and ending at the remarkable limestone headland of Portland Bill. This area is probably the richest part of Britain and Ireland for plants, with over 800 species recorded for the New Atlas of the Flora of Britain and Ireland.
Portland Bill and other areas of limestone cliffs along the coast are exceptional for their limestone grassland. Being so far south and subject to mild winters, hot summers and dry conditions, they take on an almost Mediterranean character. Flowers can be abundant, especially where the grass is grazed short, and horseshoe vetch, bird's-foot trefoil, carline thistle, small scabious and squinancywort form a tight-knit community along with pyramidal orchid and bee orchid.
But surprisingly, these dry rocky grasslands are actually much more important for their rare mosses, liverworts and lichens, some of which are extremely rare. Of the bryophytes, Portland striated feather-moss and blackwort liverwort are notable, being found in just a handful of sites in the UK. Over 210 lichens have been recorded, such as flat-leaved orchal, soil jelly lichen and granulose orange lichen. All these form wonderful communities of different shapes, colours and forms on the rocks and parched soil.
Closer to the shore, lichens again form colourful communities on the coastal rocks and grow with abundant rock samphire, golden samphire, sea campion and thrift. Portland sea lavender – a neat plant with rosettes of leaves and sprays of pretty pinkish flowers - grows here and nowhere else in the world.
This incredible diversity of life extends into the sea as well. Search the shores, rocks and rock-pools at low tide and you’re like to find an outstanding range of seaweeds, forming little underwater gardens with green, red and brown algae in all sorts of remarkable shapes and sizes. The area from Peveril Point to Durlston Head is a ‘diversity hotspot’ for marine algae with many nationally rare species, particularly of the red algae; these come in all sorts of shapes, from the delicate branching fans of Atractophora hypnoides to the stiff bottle-brushes of Bornetia secundiflora and the branching Christmas-trees of Laurencia pyramidalis to the furry crusts of Erythrotrichia welwitschii.
Image:Lulworth Cove, Dorset © sagesolar under CC BY 2.0