Maritime Cliff and Slope
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Maritime Cliff and Slope Weybourne cliffs Slumped cliffs, NE Norfolk coast Description East of Cromer the cliffs become higher and more unstable. They are composed of glacial soils Maritime cliffs and slopes comprise sloping to which vary from sand to chalk marl. The vertical faces on the coastline where a break in Overstrand cliffs are generally well vegetated but slope is formed by slippage and/or coastal are subject to major landslides. Flushes caused erosion. by springs issuing from the cliffs are a feature. The six km stretch between Overstrand and In the Norfolk Coast AONB, these are ‘soft cliffs’, Mundesley is the highest, reaching 60 metres in formed from sands, clays and gravels of glacial places where the apex of the Cromer Ridge meets origin with some areas of chalk either at the base the sea. They are very unstable and subject to or as ‘rafts’ that were torn up from the bedrock by frequent landslips through water draining through ice sheets and deposited in the cliffs. They are the cliff slip, followed by erosion by the sea from unstable and subject to frequent slumping and the toe of the cliffs. landslips, particularly where water percolates into the rock, forming often less steep slopes than Beyond Mundesley the cliffs are generally more hard rock cliffs, and are therefore more easily stable, sandier and with less seepage. The colonised by vegetation. situation at Happisburgh is similar though the cliffs are lower and more prone to erosion. Just south- The vegetation of this habitat varies according to east of Happisburgh the cliffs merge with the dune the extent of exposure to wind, sun and salt spray; coast fronting Broadland. the chemistry of the underlying rock and percolating water; the water content and stability The mobile nature of the cliffs between Cromer of the substrate; and the time elapsed since the and Mundesley creates an extensive mosaic of last movement event. Cliff-top habitats can also habitats ranging from bare mud flows and dry be transformed by soil erosion processes. sand through to relatively mature unimproved grassland, scrub communities, wet flushes and In the west between Weybourne and Sheringham even small reed beds. A particular feature of the cliffs are largely nearly vertical. At Weybourne these cliffs is the colourful displays of the kidney chalk is exposed near the base of the cliffs, but by vetch in the grassland. about Sheringham (Robin's Friend) it is at beach level and extends on to the foreshore as a chalk Soft cliffs are particularly important for platform, the inshore expression of an extensive invertebrates as they provide a suite of conditions offshore chalk reef. Between Sheringham and which are rarely found together in other habitats. Cromer there are further foreshore chalk The combination of crumbly soils, hot substrates exposures, especially at West Runton where we and open conditions maintained by cliff slippages find the only chalk rocky shore in Norfolk. offer a continuity of otherwise very restricted Norfolk Coast Partnership 01328 850530 www.norfolkcoastaonb.org.uk microhabitats and these slopes support many rare sites. Further east the land is generally cultivated invertebrates. close to the cliff edge. Seepages, springs and pools are a feature of The cliff slopes are inaccessible but can be many soft cliffs and these provide the wet muds viewed from the beach at low water. Glacial required by many species of solitary bees and geology features are notable as well as their wasps for nest building. Associated with the landscape and wildlife. seepages are perched reed beds and bryophyte and rush dominated flushes. The very attractive Characteristic species & seasonality red form of the early marsh orchid is a feature. Early Marsh orchid (spring) Purple Broomrape (spring) Clifftop grassland is important for a range of Common blue butterfly (summer) species or groups including bryophytes, lichens, invertebrates (particularly woodlice, beetles and Five-spot Burnet moth (summer) flies), and barbastelle bat. Purple broom-rape is Fulmars (summer) found in cliff-top grassland notably on Beeston Sand martins (summer) Cliffs, Sidestrand and Mundesley. Other nationally Barbastelle bat (summer) scarce species include sand catchfly at Beeston How are these managed? and bulbous meadow-grass at Overstrand. Depending on the ownership of the site the cliff The cliffs are a haven for many common grass- tops can be cropped, managed as caravan sites, land butterflies and moths with large populations golf courses or left as unmanaged grassland. of Common Blue and Five-spot Burnet moth. The Each has its own management regimes. flushes are of particular importance for breeding Diptera and a number of rare or notable species The cliff slopes are generally unmanaged and of soldier-flies have been recorded. Rare beetles amongst the ‘wildest’, most natural habitats and are also associated with these cliff habitats includ- landscapes in the AONB. ing the rove beetle and various ground beetles. Further Information Fulmars nest on some of the high sandy cliffs at Norfolk Coast Integrated Landscape Guidance – Sidestrand, Overstrand and elsewhere. Coastal Towns and Villages The sandy cliffs also support small nesting www.norfolkcoastaonb.org.uk colonies of sand martins which create burrows in Natural England National Character Area profiles the soft faces of the cliff side. – 77 North Norfolk Coast, 78 Central North Where can I find these? Norfolk http://publications.naturalengland.org.uk Soft cliffs extend from Weybourne eastwards around the coast to Bacton in the AONB, and Norfolk Biodiversity Action Plans beyond to Happisburgh, in an almost unbroken www.norfolkbiodiversity.org/actionplans line. A recently opened stretch of the the England Coast Path provides access along much of the cliff top. Cliff top grassland is present at Hunstanton and between Weybourne and Mundesley sometimes as golf courses or caravan This information sheet has been compiled from the Norfolk Wildlife Trust, Norfolk Biodiversity Partnership and Buglife websites and the North Norfolk Natural Area profile. [August 2015] Norfolk Coast Partnership 01328 850530 www.norfolkcoastaonb.org.uk .