MARITIME CLIFF AND SLOPES (UK BAP PRIORITY HABITAT)

Summary

This priority habitat takes in the vegetation that occurs on cliffs and sloping ground adjacent to the sea and includes communities specific to this habitat as well as others that also occur inland. They range from woodland through heathland to grasslands and tall herb assemblages.

There is a range of small trees or large shrubs on these coastal slopes. Most of the heaths and grasslands are herb-rich as well as having some more strictly maritime . The cliff communities vary from grassy swards in locations enriched by the droppings of nesting seabirds to tall-herb.

The habitat varies from hard, acid, near-vertical rocks to softer, more gently sloping, more basic substrates. The vegetation is exposed to salt spray, salt-laden wind and, on stormy occasions, washing with sea water, the extent and frequency of these events being greater on exposed coasts facing the prevailing wind and where waves are generally larger. The climate varies from mild in the south-west to cold in the north-east.

These are near-natural communities possibly owing more to the extreme environment than to a low level of human intervention, and contain a number of uncommon . Coastal cliffs in are important nesting habitats for such as gannet Morus bassanus, Fratercula arctica, guillemot Uria aalge, razorbill Alca torda, kittiwake Rissa tridactyla, fulmar Fulmarus glacialis, shag Phalacrocorax aristotelis and Manx shearwater Puffinus puffinus, and in the treeless Outer for grey heron Ardea cinerea.

Much of the vegetation on cliffs and steep slopes is out of the reach of grazing – except goats, which occur in some places – and is difficult to burn. In general, light grazing will maintain the vegetation. Heavy grazing and burning can convert heaths and woodlands to grassland and also initiate soil erosion and landslips.

What is it?

This priority habitat contains terrestrial plant communities of cliffs and slopes near the sea, and encompasses a great range of vegetation types from scrub woodland to grassland, heath and .

Coastal scrub

Several scrub communities occur on coastal slopes, with a canopy of tall shrubs or small trees such as hawthorn Crataegus monogyna, gorse Ulex europaeus, blackthorn Prunus spinosa, hazel Corylus avellana, bramble Rubus fruticosus or raspberry R. idaeus and an understorey of species such as bracken Pteridium aquilinum, ivy Hedera helix, red campion Silene dioica, nettle Urtica dioica, cleavers Galium aparine, ground ivy Glechoma hederacea, creeping soft-grass Holcus mollis and false oat-grass Arrhenatherum elatius. On richer soils wild hyacinth Hyacinthoides non-scripta and primrose vulgaris are common. Maritime species such as sea campion Silene uniflora and thrift may also occur. Patches of coastal scrub tend to be small, especially on the more exposed west coast, where they tend to be tucked into sheltered coves and gullies or pruned hard against the cliffs in a sort of near-vertical carpet.

Coastal heath

The H7 Calluna vulgaris- verna heath is a coastal community with a dark, dense sward of Calluna vulgaris and Erica cinerea dotted with small species such as wild thyme Thymus polytrichus, ’s-foot trefoil Lotus corniculatus, Yorkshire fog , sheep’s fescue ovina, tormentil erecta, kidney vetch Anthyllis vulneraria, ribwort plantain Plantago lanceolata and the maritime species spring squill Scilla verna, Armeria maritima, Silene uniflora and Plantago maritima. In addition, stands of the Scilla verna sub- community H8d of the Calluna vulgaris-Ulex gallii heath are also distinctly coastal. The sward of C. vulgaris, U. gallii and Erica cinerea is a dazzling sight in summer when the shrubs are in with the bright yellow of the gorse set off by the purple and magenta tones of the heathers. Again, the maritime plants Scilla verna, Armeria maritima and sea plantain Plantago maritima are common here, along with other small species such as Thymus polytrichus, Lotus corniculatus, Festuca ovina and cat’s-ear Hypochoeris radicata.

Coastal grassland

Short, hard-grazed, species-rich grasslands are common on coastal slopes. In the upland climate of the north and west the most common of these communities is the CG10 Festuca ovina-Agrostis capillaris-Thymus polytrichus grassland, with a sward made up of these species together with sweet vernal grass Anthoxanthum odoratum, common dog-violet Viola riviniana, selfheal Prunella vulgaris and Plantago lanceolata. The maritime species Armeria maritima and Plantago maritima are common. Where the soils are flushed the grasslands have a grey-green, sedge sward with glaucous sedge Carex flacca, flea sedge C. pulicaris and carnation sedge C. panicea. In the far north and west, montane plants such as hair sedge C. capillaris, alpine bistort Persicaria vivipara and alpine meadow-rue Thalictrum alpinum grow close to sea-level in this type of grassland.

In the south and east of Scotland much of the short, herb-rich coastal grassland belongs to the CG2 Festuca ovina-Avenula pratensis grassland. This has a sward of grasses such as F. ovina, crested hair-grass Koeleria macrantha, early hair-grass Aira praecox and meadow oat-grass Avenula pratensis, with some Carex flacca and spring sedge C. caryophyllea and an array of small plants such as Thymus polytrichus, Plantago lanceolata, P. maritima, lady’s bedstraw Galium verum, mouse-ear hawkweed Pilosella officinarum, harebell Campanula rotundifolia, Anthyllis vulneraria, Armeria maritima and black medick Medicago lupulina.

U4 Festuca-Agrostis-Galium grasslands occur on acid soils near the sea. They have a short, bright green, species-poor sward of Festuca ovina, F. rubra, Agrostis capillaris, Anthoxanthum odoratum, Potentilla erecta and Galium saxatile.

The mesotrophic grasslands MG1 and MG5 can also clothe coastal slopes where grazing is light or absent. MG1 has a tall and rank sward of Arrhenatherum elatius, glomerata and Hocus lanatus, scattered with large herbs such as hogweed Heracleum sphondylium, yarrow Achillea millefolium and ragwort Senecio jacobaea. MG5 has a sward of crested dog’s-tail Cynosurus cristatus, , Agrostis capillaris, Anthoxanthum odoratum, Holcus lanatus and cock’s-foot , and a rich array of herbs such as Trifolium pratense, T. repens, Galium verum, Achillea millefolium, black knapweed nigra, yellow rattle Rhinanthus minor and Lotus corniculatus.

Maritime cliff communities

The vegetation of maritime cliff ledges is distinctive and is represented in Scotland by eleven NVC communities. Some of these such as the MC1 Crithmum maritimum-Spergularia rupestris, MC2 Armeria maritima-Ligusticum scoticum and MC4 Brassica oleracea crevice communities are open assemblages dominated by a particular large maritime species. Others are more diverse, such as the MC5 Armeria-Cerastium diffusum community that consists of a great array of small herbs such as Anthyllis vulneraria, Armeria maritima, Plantago maritima, buck’s-horn plantain P. coronopus, sea mouse-ear Cerastium diffusum, Achillea millefolium and biting stonecrop Sedum acre. The MC3 Sedum rosea-Armeria maritima ledge community can have a rich and luxuriant sward of tall herbs such as roseroot Sedum rosea, Silene uniflora, S. dioica, wild angelica Angelica sylvestris and Scot’s lovage Ligusticum scoticum. There are distinctive assemblages that develop on bird cliffs: the MC6 Atriplex prostrata- Beta uniflora community (which can also occur in the Coastal vegetated shingle priority habitat) and the MC7 Stellaria media-Rumex acetosa community. The remaining communites are maritime grasslands generally dominated by Festuca rubra. The MC8 Festuca rubra-Armeria maritima grassland has a bulky sward of F. rubra; MC9 F. rubra-Holcus lanatus grassland has a rank tussocky sward of these two species and Dactylis glomerata; MC10 F. rubra-Plantago maritima grassland has a short, close-grazed sward of these species; and MC12 F. rubra-Hyacinthoides non-scripta community is a lush sward dominated by H. non-scripta.

The maritime species Plantago maritima, Armeria maritima and Scilla verna can occur in all these grasslands.

In general the flora of maritime cliffs indicates that the soils are mostly neutral to basic as shown by the presence of species such as Thymus polytrichus, Holcus lanatus, Sedum rosea and Angelica sylvestris. Strongly acidic soils and markedly acidophilous plant communities are uncommon here, possibly because of enrichment of soils from mineral salts brought in with sea spray. In some western areas the cliffs are constantly wet because of the high rainfall, and can have wetland communities on ledges and in crevices with species such as black bog-rush Schoenus nigricans, hemp-agrimony Eupatorium cannabinum, royal fern Osmunda regalis and marsh pennywort Hydrocotyle vulgaris.

How do I recognise it?

Differentiation from other priority habitats

The specifically coastal heaths, grasslands and cliff communities can be distinguished from terrestrial forms of the same types of vegetation by the presence of maritime species such as Armeria maritima, Plantago maritima, P. coronopus, Scilla verna, Silene uniflora and common scurvy-grass Cochlearia officinalis. Communities such as woodland and scrub and a range of other NVC types are assigned to this priority type where they occur in this habitat – steep cliffs and slopes running down to the sea.

Definition in relation to other habitat classifications

Classification Habitat types belonging to this UK BAP priority habitat CG1-2, CG4, CG6, CG10 (examples on coastal cliffs), H7, H8d, H10 (forms on coastal cliffs), MC1-5 (all examples), MC6 (where on coastal cliffs but not on coastal vegetated shingle), MC7-12, MG1, MG5, U4, U20, W21-25 (examples on coastal cliffs), and NVC non-NVC Schoenus nigricans-Eupatorium cannabinum cliff-ledge community (all examples). CG10, H7-8, MC1-12, MG5 and W21-22 are included in the Scottish Biodiversity List. CG1, CG4, CG6 and MC11 are not recorded in Scotland. The Maritime cliff and slopes priority habitat includes 16 Phase 1 habitat types, all of which occur in Scotland: A1-2, B1-3, B5, C1, Phase 1 C3, E2, F1, G1-2, H3, H5 (all examples of these Phase 1habitats which are on coastal slopes), H8 (examples whose vegetation is not in the Lowland heath priority habitat) and J1 (all examples on coastal slopes). UK BAP broad All examples of the Maritime cliff and slopes habitat in Britain habitat belong in the UK BAP broad habitat - Supralittoral rock.

Definition in relation to legislative classifications

Classification Habitat types belonging to this UK BAP priority habitat Habitats Directive The Maritime cliff and slopes priority habitat includes all Annex I examples of one Annex I habitat: H1230. SNH SSSI habitat The Maritime cliff and slopes priority habitat equates to the features Maritime cliff SSSI habitat feature.

Where is it?

The Maritime cliff and slopes communities occur on coastal slopes and cliffs, between the break of slope where the land begins to drop to the sea and the level of the highest tides. They are not regularly covered by sea water like saltmarsh vegetation but they are exposed to sea spray, salt-laden winds and, in some places, bird droppings. Soils tend to be thin and to dry out rapidly in hot weather. The nutrient status of the soil depends on that of the underlying rock and can vary from highly acid to highly basic.

Sea spray is more of an influence on rocky coasts, especially in the west, where the larger waves generated by the strong prevailing wind over a long fetch of sea deposit more salt higher up cliffs and further inland than on sandy, sheltered shores. Indeed, in extremely exposed coastal habitats such as the Isle of Lewis, salt marsh vegetation can occur on cliff tops as can sand dunes, as a result of beach sand being blown inland. The influence of salt on the vegetation is diluted in the wetter western parts of Scotland because of the heavy rainfall that washes much of it out of the soil and off the plants themselves, so non-maritime vegetation such as heaths, grasslands and scrub can occur close to the shore.

Maritime cliffs are generally the result of coastal erosion, although they can pre-date the current sea level and so only their lower portions have been over-steepened by marine erosion. Cliffs can be classed as ‘hard’ or ‘soft’, although intermediates occur. Hard cliffs are made of resistant rocks and tend to be steep or near-vertical, with plant growth limited to crevices, ledges and benches where soil has been able to accumulate. Soft cliffs are made of less resistant rock and form gentler slopes that are subject to slumping and landslips. They usually have a more continuous covering of vegetation. Bird cliffs tend to have distinctive vegetation because of the high concentration of nitrogen in bird droppings and because of the trampling and disturbance by nesting and courting birds.

Maritime grasslands generally occur away from the areas most washed by the sea; unlike the cliff and crevice communities they are produced and maintained by grazing.

In a seaward direction the Maritime cliff and slopes priority habitat gives way to rocky, bouldery, stony or sandy shores in the intertidal zone and below the low water mark. These can include some strictly marine priority habitats such as Intertidal underboulder communities and Subtidal sands and gravels.

In a landward direction the Maritime cliff and slopes priority habitat extends to the inland limit of the influence of sea spray. This means that the habitat can include level or gently sloping ground at and inland from the tops of the cliffs themselves, and in very exposed western areas can extend inland for as much as a few hundred metres. Along the inland edge, this priority habitat can adjoin a wide range of other habitats including grasslands, heaths, scrub, woodland and bracken, including other UK BAP priority habitats such as Lowland calcareous grassland, Lowland dry acid grassland, Upland calcareous grassland, Upland heathland, Lowland mixed deciduous woodland, Upland oakwood, Upland birchwoods and Upland mixed ashwoods.

Maritime cliff and slopes is common and widespread along the Scottish coastline, accounting for a large proportion of the coastline in many areas such as Mull, Skye, Rum, , St Kilda, , , , E and N , Berwickshire, the Mull of Galloway and parts of Banffshire, Aberdeenshire and Angus. The total length of coastline with Maritime cliff and slopes priority habitat has been estimated to be about 4000 km in the UK (UK BAP 2008), and at least 1778.5 km in Scotland (Ellis and Munro 2004).

Maritime cliff and slopes communities occur widely along the Atlantic coast of Europe, and in Ireland and the Faroe Islands.

What is special about it?

Some species of special conservation status recorded in this priority habitat in Scotland are listed below.

Wildlife EC Scottish and UK BAP Habitats Bio- Red Country- Common priority Directive diversity Data side Act Group name Latin name list Annex II List List (1981) , carder- wasps and Bombus muscorum y y ants bees, red-shanked Bombus ruderarius y y Wildlife EC Scottish and UK BAP Habitats Bio- Red Country- Common priority Directive diversity Data side Act Group name Latin name list Annex II List List (1981) wasps and carder-bee ants bees, wall mason wasps and Osmia parietina y y bee ants Carduelis flavirostris birds twite subsp. y y y bensonorum/pipilans birds hooded crow Corvus cornix y birds peregrine Falco peregrinus y y birds kestrel Falco tinnunculus y Larus argentatus birds herring gull y y y subsp. argenteus Pyrrhocorax birds chough y y pyrrhocorax Stercorarius birds Arctic skua y y y parasiticus birds troglodytes subsp. y y y fridariensis Troglodytes birds troglodytes subsp. y y y hirtensis northern Aricia artaxerxes y y brown argus butterflies small blue Cupido minimus y y y butterflies Hipparchia semele y y butterflies wall megera y y flowering pyramidal Ajuga pyramidalis y y y plants bugle flowering purple milk- Astragalus danicus y y y plants vetch flowering chamomile Chamaemelum nobile y y plants flowering stinking Chenopodium y y y plants goosefoot vulvaria flowering Scottish Cochlearia officinalis y y plants scurvygrass subsp. scotica flowering frog orchid Coeloglossum viride y y y plants Dactylorhiza flowering a northern purpurella subsp. y y plants marsh-orchid cambrensis flowering Euphrasia an eyebright y y y plants campbelliae flowering an eyebright Euphrasia marshallii y y y plants flowering an eyebright Euphrasia ostenfeldii y y y plants flowering an eyebright Euphrasia rotundifolia y y y plants purple flowering ramping- Fumaria purpurea y y plants fumitory flowering Gentianella field gentian y y y plants campestris flowering Hieracium sect. a hawkweed y y plants Alpestria flowering juniper Juniperus communis y y plants Shetland flowering Pilosella flagellaris mouse-ear- y y y plants subsp. bicapitata hawkweed flowering small-flowered Silene gallica y y y plants catchfly big blue fungi Entoloma bloxamii y y pinkgill fungi dark-purple Geoglossum y y Wildlife EC Scottish and UK BAP Habitats Bio- Red Country- Common priority Directive diversity Data side Act Group name Latin name list Annex II List List (1981) earthtongue atropurpureum Hohenbuehelia fungi marram oyster y y culmicola date-coloured fungi Hygrocybe spadicea y y waxcap olive Microglossum fungi y y earthtongue olivaceum a Arthonia atlantica y y y lichens a lichen Cladonia peziziformis y y y lichens a lichen Collema fragile y y y lichens a lichen Toninia sedifolia y y Wilson's liverworts Acrobolbus wilsonii y y pouchwort Holt`s liverworts Lejeunea holtii y y y pouncewort otter Lutra lutra y y y y narrow- molluscs mouthed Vertigo angustior y y y whorl snail bright-green Cyclodictyon y y y y cave-moss laetevirens elegant Eurhynchium mosses y y y feather-moss pulchellum reptiles slow-worm Anguis fragilis y y y reptiles common lizard Zootoca vivipara y y y

The ungrazed coastal communities may be near-natural examples of vegetation, owing more to the extreme environment than to a low level of human intervention. Uncommon species include Scilla verna, purple milk vetch Astragalus danicus, purple oxytropis Oxytropis halleri and Scottish primrose .

Bryophytes and lichens can be common on Maritime cliff and slopes, and include the strictly maritime moss Schistidium maritimum and conspicuous growths of fruticose lichens of the Ramalina. The moss Kindbergia praelonga can be very common among vascular plants on moist soils, and in sheltered crevices and gullies in the west there can be rich floras of oceanic bryophytes such as Lejeunea spp., Frullania spp., Radula aquilegia and Plagiochila killarniensis.

The zone just above high-tide level is home to an array of salt-tolerant lichens including the uncommon Pyrenocollema pelvetiae, Lichina spp., Buellia coniops, Caloplaca scopularis and Lecanora straminea. (Gilbert 2000).

In south-west Scotland, chough Pyrrhocorax pyrrhocorax, breed on coastal cliffs whilst the associated grasslands are prime feeding habitat for them. Scottish coastal cliffs hold about 70% of the world’s population of breeding gannet and also have important populations of shag, razorbill, guillemot, Manx shearwater and . Birds such as peregrine Falco peregrinus and raven Corvus corax nest on coastal cliffs, as do sea eagles Haliaeetus albicilla and, in the largely treeless Hebrides, grey heron Ardea cinerea.

There are important invertebrate assemblages on coastal cliffs and associated short, grazed grasslands, for example species of burnet in herb-rich swards on some sunny south- facing slopes.

How do we manage it?

Cliff ledge and crevice vegetation is ungrazed and essentially unmanaged, the main threats coming from coastal climbing on popular routes, large local changes in seabird populations and natural erosion and decay of coastal rocks. The terrestrial grasslands and heaths are generally open to grazing and are best maintained by light grazing. Scrubby woodland may be damaged by browsing and short-term fencing may be necessary to initiate regeneration.

References, links and further reading Averis, A., Averis, B., Birks, J., Horsfield, D., Thompson, D., & Yeo, M. 2004. An Illustrated Guide to British Upland Vegetation. Peterborough, JNCC http://jncc.defra.gov.uk/page-2463

Ellis, N.E. and Munro, K. 2004. A preliminary review of the distribution and extent of BAP priority habitats across Scotland. Scottish Natural Heritage Commissioned Report No.044 (ROAME No. F00NA02). https://www.nature.scot/information-library-data-and-research/information-library

Rodwell, J.S. ed. 2000. British Plant Communities. Volume 5 - Maritime Cliffs, Sand Dunes, Saltmarshes and Other Vegetation. Cambridge, Cambridge University Press.

Rodwell, J.S., Dring, J.C., Averis, A.B.G., Proctor, M.C.F., Malloch, A.J.C., Schaminee, J.H.J. & Dargie, T.C.D. 1998. Review of coverage of the National Vegetation Classification. Joint Nature Conservation Committee contract report F76-01-170. Coordinated by the Unit of Vegetation Science, Lancaster University.

UK BAP 2008. http://jncc.defra.gov.uk/pdf/UKBAP_BAPHabitats-34-MaritimeCliffSlopes.pdf

Usher, M.B., Bain, C. and Kerr, A. eds. 2000. Action for Scotland's Biodiversity. Scottish Biodiversity Group. Edinburgh, The Scottish Executive and The Stationery Office.

Common Standards Monitoring guidance http://www.jncc.gov.uk/page-2199

Countryside Survey: http://www.countrysidesurvey.org.uk

National Biodiversity Network (NBN) Gateway https://data.nbn.org.uk/

Scottish Government website – information about agricultural grants, subsidies and services: http://www.scotland.gov.uk/Topics/farmingrural/Agriculture/grants/A-Z/Intro

Scottish Natural Heritage website: http://www.nature.scot

UKBAP information on JNCC website: http://jncc.defra.gov.uk/default.aspx?page=5155