Skomer Island and Middleholm

Site of Special Scientific Interest · 51.7368, -5.2937

Climate exposure

This is about exposure to a nationwide pressure this habitat type carries — not a verdict on this site's own management.

Coastal

Coastal habitats are exposed to sea-level rise and storm erosion. Where hard sea defences sit behind them, there's nowhere landward to retreat to — a squeeze that keeps compressing the habitat no matter how well it's managed.

Geology & landscape

Geological Period: Ordovician, Silurian

Landscape processes: Coastal, Fluvial, Volcanic / Igneous

Birds & fish recorded

Birds

SpeciesSeason
phalacrocorax aristotelis Breeding
Manx shearwater Breeding
cormorant Breeding
curlew Breeding
curlew Wintering
fulmar Breeding
gadwall Breeding
gadwall Wintering
great black-backed gull Breeding
guillemot Breeding
herring gull Breeding
kittiwake Breeding
lapwing Breeding
lapwing Wintering
lesser black-backed gull Breeding
mallard Breeding
mallard Wintering
oystercatcher Breeding
peregrine Breeding
puffin Breeding
razorbill Breeding
shelduck Breeding
shelduck Wintering
shoveler Breeding
shoveler Wintering
teal Breeding
teal Wintering
wheatear Breeding

Description

Description The site is of special interest for its breeding seabird colonies, in particular for Manx shearwater Puffinus puffinus, puffin Fratercula arctica, storm petrel Hydrobates pelagicus, razorbill Alca torda, guillemot Uria aalge, lesser black-backed gull Larus fuscus, kittiwake Rissa tridactyla, for breeding chough Pyrrhocorax pyrrhocorax and short-eared owl Asio flammeus as well as for grey seal Halichoerus grypus which breed and haul out on the foreshore. The reef communities of the littoral zone, together with the sea caves around the island, is also of special interest. The endemic Skomer vole Myodes glareolus skomerensis breeds on Skomer Island, and a number of nationally rare and scarce plants and lichens occur including three-lobed crowfoot Ranunculus tripartitus, the scheduled golden hair lichen Teloschistes flavicans and an assemblage of nationally scarce lichens. Maritime grassland and the cliff crevice zone are also of special interest together with a rich assemblage of coastal invertebrates. The islands are also of special geological interest. Skomer and Middleholm are located 1km west of the Marloes peninsula, separated from the mainland by the narrow tide race of Jack Sound. The resistant volcanic rocks, of Silurian age, with some interbedded sediments, form a plateau with numerous small rock outcrops bordered by steep sea cliffs up to 60 metres high. These cliffs have many narrow inlets (or “wicks”), sea caves and stacks. GEOLOGY The Skomer Volcanic Group, of Llandovery age, is significant amongst the Lower Palaeozoic rocks of the southern Caledonides for two reasons. Firstly, it post-dates the bulk of the volcanism which was largely confined to the Ordovician Period. Secondly, the volcanic products are mildly alkaline in composition and contrast with the tholeitic to mildly transitional character of the Ordovician volcanics. On Skomer Island and Middleholm the well-exposed volcanic succession is 1000m thick, and comprises alkali basalts, hawaiites, mugearites, rare benmorites and rhyolites, interbedded with fluvial sandstones. Eruption of the lavas was principally sub-aerial, as indicated by the presence of red boles on the tops of many flows, although the local minor development of pillow structures indicates some subaqueous eruptions. A single ignimbrite flow, which can be traced from Skomer Island to Middleholm and the mainland, provides an important stratigraphic marker horizon. BIOLOGY The majority of the littoral zone consists of exposed bedrock, with the western sides of the island and its associated islets being subject to the greatest exposure. The sub-tidal fringe in these exposed areas is characterised by encrusting coralline algae, dabberlocks Alaria esculenta and dense aggregations of small mussels Mytilus edulis, or by kelp Laminaria digitata and dabberlocks overlying coralline and filamentous red algae. Less exposed areas support kelp with Himanthalia elongata overlying a similar community. Areas subject to strong water movement such as surge gullies and the areas between islets support a diverse under storey of sponges, sea squirts and encrusting bryozoans. Low shore communities include such rare species as the usually sub-tidal cup-coral Balonophyllia regia. Specialised habitats such as caves and rock pools are characterised by species normally found below the sub-tidal algal zone such as elephant’s ear sponge Pachymastima johnstonia. Further up-shore, exposed areas are dominated by encrusting barnacles such as Semibalanus balanoides and limpets Patella sp., with occasional patches of the exposed form of bladder wrack Fucus vesiculosus var. linearis where the bedrock becomes less steep, and a thin, broken cover of the pygmy lichen Lichina pygmaea higher on the shores. There is also a distinct horizontal band of pepper dulse Osmundea pinnatifida on the north-western side of Skomer. Less exposed areas have a mid-shore characterised by encrusting coralline algae such as Corallina officinalis with mussels or occasional thong-weed Himanthalia elongata. In more sheltered conditions such as within South Haven, serrated wrack Fucus serratus and red algae dominate with knotted wrack Ascophyllum nodosum above. A rich under-boulder community exists here, with species such as Montagu’s crab Xantho hydrophilus, velvet swimming crab Necora puber and hairy crab Pilumnus hirtellus, together with fish species such as the clingfish Lepadogaster lepadogaster and the worm pipefish Nerophis lumbriciformis. Other sheltered inlets and beaches are characterised by channelled wrack Pelvetia canaliculata and spiral wrack Fucus spiralis below the lichen zone and above an often-scoured cover of barnacles and bedrock or boulders. A band of black tar lichen Verrucaria maura with laver bread seaweed Porphyra sp. occurs below yellow and grey lichen bands dominated by Ramalina sp. These bands are particularly wide (up to 40 metres) on the more exposed western sides of the site. The sea-cliff vegetation varies from maritime grassland and cliff crevice communities in the west and south where exposure to salt-laden winds is greatest, to pockets of cliff scrub in the more sheltered northeast. Hummocks of thrift Armeria maritima and areas of sea-campion Silene uniflora characterise the much-modified maritime grassland, which is heavily grazed by rabbits on Skomer, and further modified by the manuring and trampling effects of sea-birds. Heathland, both maritime and inland, occurs only in small patches dominated by heather Calluna vulgaris. Bracken Pteridium aquilinum covers much of the interior, but purple moor-grass Molinia caerulea occurs in the valleys, and there are areas of short acidic grassland in the old fields surrounding the farmhouse on Skomer. Bluebell Hyacinthoides non-scripta and red campion Silene dioica flourish under the bracken. The diversity of microhabitats at this site has allowed the development of species-rich lichen communities that support a high number of rare and specialist species. These include those associated with nutrient enrichment of rock and soil surfaces by seabirds, such as Ramalina polymorpha and Aspicilia epiglypta. Other species of note include the scheduled golden hair lichen Teloschistes flavicans, the nationally rare species Parmelia tinctina, Caloplaca britannica and Arthonia atlantica, together with Porina curnowii and Rinodina orculariopsis, all of which are associated with rock (saxicolous). Species associated with the ground surface (terricolous) include the nationally scarce Rinodina conradii, found on soil, heather stems or rabbit pellets, and Trapeliopsis wallrothii, found on turf and soil. Higher plants include the nationally scarce three-lobed crowfoot, in shallow pools or scrapes, and the nationally scarce lanceolate spleenwort Asplenium obovatum, Portland spurge Euphorbia portlandica and rock sea-lavender Limonium procerum ssp procerum. Other interesting species are chaffweed Centunculus minimus, sea stork’s-bill Erodium maritimum and the large, fleshy-leaved variety of buck’s-horn plantain Plantago coronopus var. maritimus. Skomer Island and Middleholm together support the largest concentrations of breeding seabirds in England and Wales. Razorbill nest on the cliffs in their thousands, along with many thousands of the burrow-nesting puffin and the nocturnal storm petrel. Nearly half of the UK population of Manx shearwater also breeds here, again numbering many thousands. Skomer and Middleholm also support other breeding seabirds in large numbers, including lesser black-backed gull, guillemot, kittiwake, and fulmar Fulmarus glacialis, together with herring gull Larus argentatus and greater black-backed gull Larus marinus, cormorant Phalacrocorax carbo and shag Phalacrocorax aristotelis. Chough also breed on the cliffs, feeding within the short maritime grassland, and the short-eared owl breeds in the interior of the island, feeding on small mammals. Other breeding birds include peregrine Falco peregrinus, oystercatcher Haematopus ostralegus, lapwing Vanellus vanellus, skylark Alauda arvensis, curlew Numenius arquata, wheatear Oenanthe oenanthe, linnet Carduelis cannabina, and reed bunting Emberiza schoeniclus. The ponds on Skomer support the only breeding gadwall Mareca strepera in Pembrokeshire, along with mallard Anas platyrhynchos and shoveler A. clypeata. Shelduck Tadorna tadorna and teal Anas crecca occasionally nest, and teal also overwinter. A unique race of the bank vole Myodes glareolus skomerensis that is peculiar to Skomer occurs on the island, favouring areas of dense bracken with little understorey. The grey seal breeds and hauls out on the beaches and in the caves around Skomer and Middleholm. Around 10% of the South West Wales grey seal population pups are born here annually. An assemblage of scarce invertebrates, mainly beetles and moths, has been identified, associated with the coast or the ponds. These include the ground beetle Masoreus wetterhallii, which has been found on rabbit-grazed turf on Skomer, the leaf beetle Cassida hemisphaerica which feeds on sea campion, and the golden keyhole weevil Sibinia sodalis which feeds on thrift. The beetle Aepus robini occurs on the seashore, preying on maritime springtails, and the darkling beetle Crypticus quisquilius can be found on sand surfaces. Water beetles associated with the ponds on Skomer include the nationally rare Graptodytes flavipes and the scarce Helophorus griseus. Moth species include thrift clearwing Pyropteron muscaeformis and the black-banded moth Polymixis xanthomista statices, whose larval food plant is thrift, together with Barrett’s marbled coronet Conisania andalusica and the Devonshire wainscot Leucania putrescens, which both have a distinctly coastal distribution. Remarks: 1. Skomer Island is owned by the Countryside Council for Wales (CCW) and leased to the Wildlife Trust West Wales. The foreshore around both Skomer and Middleholm is leased to CCW from the Crown Estate. Middleholm is owned by the National Trust. 2. Skomer Island down to Mean Low Water Mark, and the foreshore around Middleholm, is designated as a National Nature Reserve. The foreshore from Highest Astronomical Tide (HAT) seawards is included within Skomer Marine Nature Reserve. The foreshore is also included within Pembrokeshire Marine/Sir Benfro Fôrol Special Area for Conservation (cSAC) for its reef and grey seal features. Skomer Island and Middleholm are part of the Skomer and Skokholm Special Protection Area (SPA). 3. The SSSI lies within Pembrokeshire Coast National Park. 4. The grey seal is listed in Annex IIa of the EC Habitats Directive (Directive 92/43/EEC on the Conservation of Natural Habitats and of Wild Flora and Fauna). 5. Golden hair lichen Teloschistes flavicans is listed on Schedule 8 of the Wildlife and Countryside Act 1981 (as amended).

Species mentioned

English name
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Latin name
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IUCN / Red List Type Family
dabberlocks Alaria esculenta Not listed in GB list algae brown alariaceae
egg wrack Ascophyllum nodosum Not listed in GB list algae brown fucaceae
serrated wrack Fucus serratus Not listed in GB list algae brown fucaceae
spiraled wrack Fucus spiralis Not listed in GB list algae brown fucaceae
bladder wrack Fucus vesiculosus Not listed in GB list algae brown fucaceae
thong weed Himanthalia elongata Not listed in GB list algae brown himanthaliaceae
oar weed Laminaria digitata Not listed in GB list algae brown laminariaceae
channel wrack Pelvetia canaliculata Not listed in GB list algae brown fucaceae
common coral weed Corallina officinalis Not listed in GB list algae red corallinaceae
pepper dulse Osmundea pinnatifida Not listed in GB list algae red rhodomelaceae
acorn barnacle Semibalanus balanoides Not listed in GB list barnacle archaeobalanidae
beetle Aepus robini Not listed in GB list beetle carabidae
no common name Masoreus wetterhallii LC beetle ground carabidae
linnet Linaria cannabina EN (Breeding) bird fringillidae
Phalacrocorax aristotelis Not listed in GB list bird phalacrocoracidae
razorbill Alca torda LC (Breeding) bird-auk alcidae
puffin Fratercula arctica CR (Breeding) bird-auk alcidae
guillemot Uria aalge LC (Breeding) bird-auk alcidae
reed bunting Emberiza schoeniclus LC (Breeding) bird-bunting emberizidae
chough Pyrrhocorax pyrrhocorax VU (Breeding) bird-corvid corvidae
teal Anas crecca LC (NonBreeding), LC (Breeding) bird-duck anatidae
mallard Anas platyrhynchos NT (NonBreeding), LC (Breeding) bird-duck anatidae
gadwall Mareca strepera LC (NonBreeding), LC (Breeding) bird-duck anatidae
shoveler Spatula clypeata LC (NonBreeding), LC (Breeding) bird-duck anatidae
shelduck Tadorna tadorna EN (NonBreeding), EN (Breeding) bird-duck anatidae
linnet Carduelis cannabina Not listed in GB list bird-finch fringillidae
shag Gulosus aristotelis VU (Breeding) bird-frigate fregatidae
cormorant Phalacrocorax carbo NT (Breeding) bird-frigate fregatidae
fulmar Fulmarus glacialis CR (Breeding) bird-fulmar procellariidae
herring gull Larus argentatus EN (NonBreeding), EN (Breeding) bird-gull laridae
lesser black-backed gull Larus fuscus DD (Breeding) bird-gull laridae
great black-backed gull Larus marinus EN (NonBreeding), CR (Breeding) bird-gull laridae
kittiwake Rissa tridactyla EN (Breeding) bird-gull laridae
peregrine Falco peregrinus LC (Breeding) bird-hawk falconidae
skylark Alauda arvensis VU (Breeding) bird-lark alaudidae
short-eared owl Asio flammeus EN (Breeding) bird-owl strigidae
storm petrel Hydrobates pelagicus LC (Breeding) bird-petrel hydrobatidae
wheatear Oenanthe oenanthe LC (Breeding) bird-robin muscicapidae
Manx shearwater Puffinus puffinus LC (Breeding) bird-sheerwater procellariidae
oystercatcher Haematopus ostralegus LC (Breeding) bird-wader haematopodidae
curlew Numenius arquata EN (Breeding) bird-wader scolopacidae
lapwing Vanellus vanellus VU (NonBreeding), EN (Breeding) bird-wader charadriidae
blue mussel Mytilus edulis LC bivalve mytilidae
scarlet and gold star coral Balonophyllia regia Not listed in GB list coral dendrophylliidae
crab Xantho hydrophilus Not listed in GB list crustacean xanthidae
bracken Pteridium aquilinum LC fern dennstaedtiaceae
purple moor grass Molinia caerulea LC grass poaceae
thrift Armeria maritima CR herb plumbaginaceae
lanceolate spleenwort Asplenium obovatum LC herb aspleniaceae
chaffweed Centunculus minimus Not listed in GB list herb primulaceae
sea stork's-bill Erodium maritimum LC herb geraniaceae
Portland spurge Euphorbia portlandica LC herb euphorbiaceae
bluebell Hyacinthoides non-scripta LC herb liliaceae
rock sea-lavender Limonium procerum Not listed in GB list herb plumbaginaceae
buck's-horn plantain Plantago coronopus LC herb plantaginaceae
three-lobed crowfoot Ranunculus tripartitus VU herb ranunculaceae
red campion Silene dioica LC herb carophyllaceae
sea campion Silene uniflora LC herb carophyllaceae
Lichina pygmaea LC lichen lichinaceae
no common name Parmelia tinctina Not listed in GB list lichen no common name
bird-perch gristle lichen Ramalina polymorpha NT lichen no common name
powdered orange bush lichen Teloschistes flavicans VU lichen no common name
scaly mottled-disc lichen Trapeliopsis wallrothii LC lichen no common name
sea tar Verrucaria maura Not listed in GB list lichen no common name
Barrett's marbled Conisania andalusica Not listed in GB list moth noctuidae
Devonshire wainscot Leucania putrescens Not listed in GB list moth noctuidae
black-banded Polymixis xanthomista Not listed in GB list moth noctuidae
thrift clearwing Pyropteron muscaeformis Not listed in GB list moth sesiidae
Skomer vole Myodes glareolus skomerensis Not listed in GB list rodent cricetidae
grey seal Halichoerus grypus None seal phocidae
bell heather or ling Calluna vulgaris NT shrub dwarf ericaceae
elephant's ear sponge Pachymastima johnstonia Not listed in GB list sponge geodiidae

Insects to look out for

These moths, butterflies and beetles are known to feed on plants recorded at this site, and carry a notable UK conservation status — but a host-plant being present doesn't mean the insect has actually been recorded here. Treat this as "worth watching for," not a confirmed sighting.

SpeciesStatusVia host-plant
Chequered skipper
Carterocephalus palaemon
Endangered Molinia caerulea
The grey
Hadena caesia
Endangered Silene uniflora
Shoulder-striped clover
Heliothis maritima
Endangered Calluna vulgaris
Glanville fritillary
Melitaea cinxia
Endangered Plantago coronopus
Broom moth
Ceramica pisi
Vulnerable Calluna vulgaris, Pteridium aquilinum
Large heath
Coenonympha tullia
Vulnerable Molinia caerulea
Marsh fritillary
Euphydryas aurinia
Vulnerable Plantago spp.
Satyr pug
Eupithecia satyrata
Vulnerable Calluna vulgaris
Garden dart
Euxoa nigricans
Vulnerable Plantago spp.
True lover's knot
Lycophotia porphyrea
Vulnerable Calluna vulgaris
Silver studded blue
Plebejus argus
Vulnerable Calluna vulgaris
The anomalous
Stilbia anomala
Vulnerable Molinia caerulea
Pale eggar
Trichiura crataegi
Vulnerable Calluna vulgaris
Flounced chestnut
Agrochola helvola
Near Threatened Calluna vulgaris
Beaded chestnut
Agrochola lychnidis
Near Threatened Ranunculus spp.
Grey chi
Antitype chi
Near Threatened Armeria maritima
Garden tiger
Arctia caja
Near Threatened Plantago spp., Pteridium aquilinum
Silver barred
Deltote bankiana
Near Threatened Molinia caerulea
Grey scalloped
Dyscia fagaria
Near Threatened Calluna vulgaris
Autumnal rustic
Eugnorisma glareosa
Near Threatened Calluna vulgaris, Hyacinthoides non-scripta, Plantago spp.
Weaver's wave
Idaea contiguaria
Near Threatened Calluna vulgaris

Host-plant data: Cook et al. (2025), Traits data for the butterflies and macro-moths of Great Britain and Ireland, 2024, UK Centre for Ecology & Hydrology / Butterfly Conservation; and Padovani et al. (2020), Database of Insects and their Food Plants (DBIF), UK Centre for Ecology & Hydrology (both Open Government Licence). Contains data supplied by UK Centre for Ecology & Hydrology.

Plant communities

H7 — Hard cliff and cliff slope, Lowland dry heath

Calluna vulgaris-Scilla verna heath

Matches 5 species from the description above: Armeria maritima, Calluna vulgaris, Molinia caerulea, Plantago coronopus, Silene uniflora

Salix repens, Empetrum nigrum subsp.nigrum, Calluna vulgaris, Erica cinerea, Erica tetralix, Erica vagans, Juniperus communis, Ulex europaeus, Carex caryophyllea, Carex flacca, Carex nigra, Carex panicea, Carex pulicaris, Carex serotina, Luzula campestris, Luzula multiflora, Selaginella selaginoides, Hypnum cupressiforme, Frullania tamarisci, Cladonia chlorophaea, Cladonia rangiformis, Daucus carota, Achillea millefolium, Hypochaeris radicata, Leontodon saxatilis, Leucanthemum vulgare, Scorzoneroides autumnalis, Serratula tinctoria, Jasione montana, Succisa pratensis, Cerastium diffusum, Cerastium fontanum, Silene uniflora, Sedum anglicum, Anthyllis vulneraria, Astragalus danicus, Genista pilosa, Lotus corniculatus, Trifolium repens, Centaurium erythraea, Thymus praecox, Scilla verna, Dactylorhiza purpurella, Euphrasia officinalis, Plantago coronopus, Plantago lanceolata, Plantago maritima, Armeria maritima, Polygala serpyllifolia, Polygala vulgaris, Rumex acetosa, Primula vulgaris, Filipendula vulgaris, Potentilla erecta, Galium verum, Viola riviniana, Agrostis capillaris, Agrostis stolonifera, Aira caryophyllea, Aira praecox, Anthoxanthum odoratum, Dactylis glomerata, Danthonia decumbens, Festuca ovina, Festuca rubra, Holcus lanatus, Koeleria macrantha, Molinia caerulea, Nardus stricta, Chara curta

W22 — Hedgerow scrub, Mixed scrub

Prunus spinosa-Rubus fruticosus scrub

Matches 5 species from the description above: Armeria maritima, Hyacinthoides non-scripta, Pteridium aquilinum, Silene dioica, Silene uniflora

Hedera helix, Acer campestre, Corylus avellana, Ulex europaeus, Prunus spinosa, Plagiomnium undulatum, Brachythecium rutabulum, Eurhynchium striatum, Kindbergia praelonga, Thuidium tamariscinum, Atrichum undulatum, Lophocolea bidentata, Achillea millefolium, Cardamine flexuosa, Lonicera periclymenum, Moehringia trinervia, Silene dioica, Silene uniflora, Stellaria media agg., Mercurialis perennis, Geranium robertianum, Stachys sylvatica, Teucrium scorodonia, Hyacinthoides non-scripta, Oxalis acetosella, Digitalis purpurea, Plantago lanceolata, Veronica chamaedrys, Armeria maritima, Rumex acetosa, Filipendula ulmaria, Geum urbanum, Rosa canina, Rubus fruticosus agg., Rubus idaeus, Galium aparine, Urtica dioica, Viola riviniana, Agrostis capillaris, Brachypodium sylvaticum, Dactylis glomerata, Festuca rubra, Holcus lanatus, Holcus mollis, Poa trivialis, Asplenium scolopendrium, Pteridium aquilinum, Dryopteris borreri, Dryopteris filix-mas

MC5 — Hard cliff and cliff slope

Armeria maritima-Cerastium diffusum ssp. diffusum maritime therophyte community

Matches 4 species from the description above: Armeria maritima, Euphorbia portlandica, Plantago coronopus, Silene uniflora

Carex flacca, Hypnum cupressiforme, Tortella flavovirens, Cladonia chlorophaea, Cladonia foliacea, Cladonia rangiformis, Collema spp., Daucus carota, Achillea millefolium, Bellis perennis, Cirsium acaule, Echium vulgare, Jacobaea vulgaris, Leontodon saxatilis, Pilosella officinarum, Senecio vulgaris, Sonchus oleraceus, Taraxacum officianalis, Tripleurospermum maritimum, Myosotis ramosissima, Brassica oleracea, Cochlearia danica, Cochlearia officinalis, Diplotaxis muralis, Jasione montana, Arenaria serpyllifolia, Cerastium diffusum, Cerastium fontanum, Herniaria ciliolata, Sagina apetala, Sagina maritima, Silene uniflora, Spergularia rupicola, Atriplex littoralis, Sedum acre, Sedum anglicum, Euphorbia portlandica, Anthyllis vulneraria, Hippocrepis comosa, Lotus corniculatus, Trifolium arvense, Trifolium occidentale, Trifolium repens, Trifolium scabrum, Vicia sativa, Centaurium erythraea, Eriodium cicutarium, Salvia verbenaca, Thymus praecox, Scilla autumnalis, Scilla verna, Radiola linoides, Plantago coronopus, Plantago lanceolata, Plantago maritima, Veronica arvensis, Armeria maritima, Ranunculus acris, Reseda lutea, Filipendula vulgaris, Poterium sanguisorba, Galium verum, Agrostis capillaris, Agrostis stolonifera, Aira caryophyllea, Aira praecox, Brachypodium pinnatum, Bromus hordeaceous, Catapodium marinum, Catapodium rigidum, Dactylis glomerata, Festuca ovina, Festuca rubra, Holcus lanatus, Koeleria macrantha, Lolium perenne, Schedonorus arundinaceus

H8 — Hard cliff and cliff slope, Lowland dry heath, Upland dry heath

Calluna vulgaris-Ulex gallii heath

Matches 3 species from the description above: Calluna vulgaris, Molinia caerulea, Pteridium aquilinum

Calluna vulgaris, Erica cinerea, Erica tetralix, Vaccinium myrtillus, Ulex europaeus, Ulex gallii, Carex binervis, Carex caryophyllea, Carex flacca, Carex pilulifera, Campylopus flexuosus, Dicranum scoparium, Hypnum cupressiforme, Pleurozium schreberi, Pseudoscleropodium purum, Rhytidiadelphus squarrosus, Polytrichum juniperinum, Polytrichum piliferum, Cladonia impexa, Cladonia squamosa, Hypochaeris radicata, Jasione montana, Lotus corniculatus, Hypericum pulchrum, Teucrium scorodonia, Thymus praecox, Scilla verna, Linum catharticum, Pedicularis sylvatica, Digitalis purpurea, Plantago lanceolata, Plantago maritima, Polygala serpyllifolia, Rumex acetosella, Potentilla erecta, Poterium sanguisorba, Rubus fruticosus agg., Galium saxatile, Galium verum, Viola lactea, Viola riviniana, Agrostis capillaris, Agrostis curtisii, Agrostis stolonifera, Agrostis vinealis, Aira praecox, Anthoxanthum odoratum, Avenula pubescens, Brachypodium sylvaticum, Dactylis glomerata, Danthonia decumbens, Deschampsia flexuosa, Festuca ovina, Festuca rubra, Holcus lanatus, Molinia caerulea, Nardus stricta, Pteridium aquilinum, Chara curta

MC1 — Hard cliff and cliff slope

Crithmum maritimum-Spergularia rupicola maritime rock-crevice community

Matches 3 species from the description above: Armeria maritima, Plantago coronopus, Silene uniflora

Tortella flavovirens, Crithmum maritimum, Daucus carota, Inula crithmoides, Tripleurospermum maritimum, Cochlearia danica, Cochlearia officinalis, Cerastium diffusum, Silene uniflora, Spergularia rupicola, Atriplex hastata, Plantago coronopus, Plantago maritima, Armeria maritima, Limonium binervosum, Catapodium marinum, Festuca rubra, Parapholis incurva, Asplenium marinum

MC2 — Hard cliff and cliff slope

Armeria maritima-Ligusticum scoticum maritime rock-crevice community

Matches 3 species from the description above: Armeria maritima, Plantago coronopus, Silene uniflora

Schistidium maritimum, Ligusticum scoticum, Scorzoneroides autumnalis, Tripleurospermum maritimum, Cochlearia officinalis, Cerastium fontanum, Silene uniflora, Spergularia rupicola, Atriplex hastata, Sedum rosea, Plantago coronopus, Plantago maritima, Armeria maritima, Rumex crispus, Agrostis stolonifera, Festuca rubra, Asplenium marinum

MC3 — Hard cliff and cliff slope

Rhodiola rosea-Armeria maritima 36-ledge community

Matches 3 species from the description above: Armeria maritima, Silene dioica, Silene uniflora

Angelica sylvestris, Ligusticum scoticum, Scorzoneroides autumnalis, Tripleurospermum maritimum, Silene dioica, Silene uniflora, Sedum rosea, Lotus corniculatus, Plantago lanceolata, Plantago maritima, Armeria maritima, Rumex acetosa, Agrostis stolonifera, Festuca rubra, Holcus lanatus

MC4 — Hard cliff and cliff slope

Brassica oleracea 36-ledge community

Matches 3 species from the description above: Armeria maritima, Plantago coronopus, Silene uniflora

Daucus carota, Centaurea nigra, Centaurea scabiosa, Cirsium arvense, Echium vulgare, Jacobaea vulgaris, Leucanthemum vulgare, Pilosella officinarum, Senecio vulgaris, Sonchus oleraceus, Taraxacum officianalis, Tragopogon pratensis, Brassica nigra, Brassica oleracea, Cheiranthus cheiri, Silene nutans, Silene uniflora, Sedum acre, Anthyllis vulneraria, Ononis repens, Teucrium scorodonia, Plantago coronopus, Plantago lanceolata, Armeria maritima, Rumex acetosa, Potentilla reptans, Galium aparine, Agrostis stolonifera, Brachypodium pinnatum, Bromus hordeaceous, Dactylis glomerata, Festuca rubra, Schedonorus arundinaceus

MC6 — Coastal vegetated shingle, Hard cliff and cliff slope

Atriplex prostrata-Beta vulgaris ssp. maritima sea-bird cliff community

Matches 3 species from the description above: Armeria maritima, Plantago coronopus, Silene uniflora

Daucus carota, Sonchus oleraceus, Taraxacum officianalis, Tripleurospermum maritimum, Cochlearia officinalis, Silene uniflora, Spergularia rupicola, Atriplex hastata, Malva arborea, Plantago coronopus, Armeria maritima, Polygonum aviculare, Rumex crispus, Bromus hordeaceous, Catapodium marinum, Dactylis glomerata, Festuca rubra

MC8 — Hard cliff and cliff slope

Festuca rubra-Armeria maritima maritime grassland

Matches 3 species from the description above: Armeria maritima, Plantago coronopus, Silene uniflora

Carex caryophyllea, Carex distans, Kindbergia praelonga, Tortella flavovirens, Trichostomum brachydontium, Angelica sylvestris, Crithmum maritimum, Daucus carota, Ligusticum scoticum, Achillea millefolium, Cirsium arvense, Hypochaeris radicata, Inula crithmoides, Leontodon saxatilis, Scorzoneroides autumnalis, Sonchus oleraceus, Tripleurospermum maritimum, Brassica oleracea, Cochlearia danica, Cochlearia officinalis, Cerastium diffusum, Cerastium fontanum, Sagina apetala, Sagina maritima, Silene uniflora, Spergularia rupicola, Sedum anglicum, Anthyllis vulneraria, Lotus corniculatus, Trifolium repens, Centaurium erythraea, Scilla verna, Plantago coronopus, Plantago lanceolata, Plantago maritima, Armeria maritima, Rumex acetosa, Potentilla erecta, Agrostis stolonifera, Brachypodium pinnatum, Catapodium marinum, Dactylis glomerata, Festuca rubra, Holcus lanatus, Poa subcaerulea

MC9 — Hard cliff and cliff slope

Festuca rubra-Holcus lanatus maritime grassland

Matches 3 species from the description above: Armeria maritima, Euphorbia portlandica, Silene uniflora

Empetrum nigrum subsp.nigrum, Carex caryophyllea, Carex flacca, Carex nigra, Carex panicea, Luzula campestris, Hypnum cupressiforme, Kindbergia praelonga, Pseudoscleropodium purum, Rhytidiadelphus squarrosus, Trichostomum brachydontium, Cladonia chlorophaea, Peltigera canina, Angelica sylvestris, Conopodium majus, Daucus carota, Heracleum sphondylium, Achillea millefolium, Bellis perennis, Centaurea nigra, Hypochaeris radicata, Jacobaea vulgaris, Leontodon saxatilis, Leucanthemum vulgare, Pilosella officinarum, Scorzoneroides autumnalis, Serratula tinctoria, Solidago virgaurea, Cochlearia officinalis, Campanula rotundifolia, Cerastium diffusum, Cerastium fontanum, Sagina apetala, Silene uniflora, Sedum anglicum, Euphorbia portlandica, Anthyllis vulneraria, Genista tinctoria, Lotus corniculatus, Trifolium repens, Geranium sanguineum, Thymus praecox, Scilla verna, Euphrasia officinalis, Plantago lanceolata, Plantago maritima, Armeria maritima, Rumex acetosa, Rumex crispus, Ficaria verna, Ranunculus acris, Potentilla erecta, Galium verum, Viola riviniana, Agrostis capillaris, Agrostis stolonifera, Aira praecox, Anthoxanthum odoratum, Brachypodium sylvaticum, Dactylis glomerata, Danthonia decumbens, Deschampsia flexuosa, Festuca ovina, Festuca rubra, Holcus lanatus, Koeleria macrantha, Poa pratensis

W21 — Hedgerow scrub, Mixed scrub

Crataegus monogyna-Hedera helix scrub

Matches 3 species from the description above: Hyacinthoides non-scripta, Pteridium aquilinum, Silene dioica

Hedera helix, Salix cinerea, Acer pseudoplatanus, Ilex aquifolium, Betula pendula, Corylus avellana, Fagus sylvatica, Quercus robur, Fraxinus excelsior, Malus sylvestris, Sorbus aria, Taxus baccata, Ulmus glabra, Ulmus procera, Sambucus nigra, Viburnum lantana, Euonymus europaeus, Cornus sanguinea, Juniperus communis, Ligustrum vulgare, Clematis vitalba, Rhamnus cathartica, Crataegus laevigata, Crataegus monogyna, Prunus spinosa, Juncus effusus, Plagiomnium undulatum, Brachythecium rutabulum, Kindbergia praelonga, Rhynchostegium confertum, Tamus communis, Heracleum sphondylium, Torilis japonica, Arum maculatum, Arctium minus, Cirsium arvense, Lonicera periclymenum, Moehringia trinervia, Silene dioica, Stellaria graminea, Stellaria holostea, Stellaria media agg., Calystegia sepium, Mercurialis perennis, Geranium robertianum, Iris foetidissima, Glechoma hederacea, Lamium purpureum, Origanum vulgare, Stachys sylvatica, Teucrium scorodonia, Allium ursinum, Hyacinthoides non-scripta, Circaea lutetiana, Rumex sanguineus, Anemone nemorosa, Ranunculus repens, Fragaria vesca, Geum urbanum, Potentilla sterilis, Poterium sanguisorba, Rosa arvensis, Rosa canina, Rubia peregrina, Rubus fruticosus agg., Galium aparine, Urtica dioica, Viola riviniana, Anisantha sterilis, Arrhenatherum elatius, Brachypodium pinnatum, Brachypodium sylvaticum, Bromopsis erecta, Dactylis glomerata, Elytrigia repens, Holcus lanatus, Holcus mollis, Poa trivialis, Asplenium scolopendrium, Pteridium aquilinum, Dryopteris filix-mas

W25 — Bracken scrub

Pteridium aquilinum-Rubus fruticosus underscrub

Matches 3 species from the description above: Hyacinthoides non-scripta, Pteridium aquilinum, Silene dioica

Hedera helix, Acer pseudoplatanus, Fagus sylvatica, Quercus robur, Fraxinus excelsior, Sambucus nigra, Ulex europaeus, Crataegus monogyna, Prunus spinosa, Luzula multiflora, Mnium hornum, Brachythecium rutabulum, Kindbergia praelonga, Angelica sylvestris, Conopodium majus, Heracleum sphondylium, Arum maculatum, Cirsium arvense, Lonicera periclymenum, Silene dioica, Stellaria holostea, Mercurialis perennis, Geranium robertianum, Glechoma hederacea, Teucrium scorodonia, Hyacinthoides non-scripta, Chamerion angustifolium, Circaea lutetiana, Digitalis purpurea, Rumex acetosa, Anemone nemorosa, Ficaria verna, Potentilla erecta, Rosa arvensis, Rosa canina, Rubus fruticosus agg., Rubus idaeus, Galium aparine, Galium mollugo sens.lat., Galium saxatile, Urtica dioica, Viola riviniana, Agrostis capillaris, Anthoxanthum odoratum, Arrhenatherum elatius, Dactylis glomerata, Festuca rubra, Holcus lanatus, Holcus mollis, Poa trivialis, Pteridium aquilinum, Dryopteris dilatata, Dryopteris filix-mas

MC7 — Hard cliff and cliff slope

Stellaria media-Rumex acetosa sea-bird cliff community

Matches 2 species from the description above: Armeria maritima, Silene uniflora

Juncus articulatus, Scorzoneroides autumnalis, Senecio vulgaris, Tripleurospermum maritimum, Cochlearia officinalis, Cerastium fontanum, Cerastium glomeratum, Silene uniflora, Spergula arvensis, Stellaria media agg., Atriplex hastata, Sedum anglicum, Trifolium repens, Plantago maritima, Armeria maritima, Polygonum aviculare, Rumex acetosa, Rumex crispus, Potentilla anserina, Agrostis stolonifera, Festuca rubra, Holcus lanatus, Poa annua, Poa pratensis

MG11 — Brownfield, Coastal floodplain grazing marsh, Hard cliff and cliff slope

Festuca rubra-Agrostis stolonifera-Potentilla anserina grassland

Matches 2 species from the description above: Silene dioica, Silene uniflora

Atriplex portulacoides, Carex arenaria, Carex distans, Juncus articulatus, Juncus bufonius, Juncus gerardii, Brachythecium rutabulum, Odontites verna, Oenanthe lachenalii, Bellis perennis, Cirsium arvense, Cirsium vulgare, Hypochaeris radicata, Matricaria discoidea, Scorzoneroides autumnalis, Senecio aquaticus, Sonchus asper, Taraxacum officianalis, Tripleurospermum maritimum, Cochlearia anglica, Cochlearia officinalis, Cerastium fontanum, Honckenya peploides, Sagina procumbens, Silene dioica, Silene uniflora, Stellaria media agg., Atriplex hastata, Lotus corniculatus, Trifolium repens, Triglochin maritimum, Plantago lanceolata, Plantago major, Plantago maritima, Polygonum aviculare, Rumex acetosa, Rumex crispus, Rumex obtusifolius, Glaux maritima, Ranunculus acris, Ranunculus repens, Potentilla anserina, Potentilla reptans, Galium aparine, Urtica dioica, Agrostis capillaris, Agrostis stolonifera, Alopecurus geniculatus, Ammophila arenaria, Arrhenatherum elatius, Bromus hordeaceous, Dactylis glomerata, Elytrigia juncea, Elytrigia repens, Festuca rubra, Holcus lanatus, Lolium perenne, Parapholis strigosa, Phleum pratense, Poa annua, Poa pratensis, Poa trivialis, Schedonorus arundinaceus, Schedonorus pratensis

MG1 — Brownfield, Hard cliff and cliff slope

Arrhenatherum elatius grassland

Matches 1 species from the description above: Pteridium aquilinum

Hedera helix, Luzula campestris, Brachythecium rutabulum, Kindbergia praelonga, Pseudoscleropodium purum, Rhytidiadelphus squarrosus, Aegopodium podagraria, Anthriscus sylvestris, Conopodium majus, Daucus carota, Heracleum sphondylium, Pimpinella major, Pimpinella saxifraga, Achillea millefolium, Artemisia vulgaris, Carduus nutans, Centaurea nigra, Centaurea scabiosa, Cirsium arvense, Cirsium vulgare, Hypochaeris radicata, Jacobaea vulgaris, Leontodon hispidus, Leucanthemum vulgare, Sonchus asper, Taraxacum officianalis, Capsella bursa-pastoris, Campanula rotundifolia, Knautia arvensis, Scabiosa columbaria, Cerastium fontanum, Silene nutans, Stellaria graminea, Convolvulus arvensis, Lathyrus pratensis, Lotus corniculatus, Lotus pedunculatus, Trifolium pratense, Trifolium repens, Vicia cracca, Vicia sativa, Vicia sepium, Geranium dissectum, Hypericum perforatum, Clinopodium vulgare, Glechoma hederacea, Lamium album, Origanum vulgare, Teucrium scorodonia, Thymus praecox, Linum catharticum, Chamerion angustifolium, Epilobium hirsutum, Epipactis purpurata, Rhinanthus minor, Papaver dubium, Plantago lanceolata, Veronica chamaedrys, Rumex acetosa, Rumex crispus, Rumex obtusifolius, Primula veris, Primula vulgaris, Ficaria verna, Ranunculus acris, Ranunculus bulbosus, Ranunculus repens, Agrimonia eupatoria, Filipendula ulmaria, Potentilla reptans, Poterium sanguisorba, Rubus fruticosus agg., Galium aparine, Galium mollugo sens.lat., Galium verum, Urtica dioica, Agrostis capillaris, Agrostis stolonifera, Alopecurus pratensis, Anisantha sterilis, Anthoxanthum odoratum, Arrhenatherum elatius, Avenula pubescens, Brachypodium sylvaticum, Briza media, Bromopsis erecta, Bromus hordeaceous, Cynosurus cristatus, Dactylis glomerata, Elytrigia repens, Festuca ovina, Festuca rubra, Holcus lanatus, Holcus mollis, Lolium perenne, Phleum pratense, Poa pratensis, Poa trivialis, Schedonorus pratensis, Trisetum flavescens, Pteridium aquilinum, Chara vulgaris

W20 — Montane scrub

Salix lapponum-Luzula sylvatica scrub

Matches 1 species from the description above: Calluna vulgaris

Salix arbuscula, Salix cinerea, Salix lapponum, Salix myrsinites, Salix phylicifolia, Salix reticulata, Empetrum nigrum, Calluna vulgaris, Salix lanata, Vaccinium myrtillus, Vaccinium uliginosum, Carex atrata, Carex bigelowii, Carex binervis, Carex flacca, Luzula multiflora, Luzula sylvatica, Huperzia selago, Selaginella selaginoides, Aulacomnium palustre, Mnium hornum, Philonotis fontana, Plagiomnium undulatum, Rhizomnium punctatum, Dicranum bonjeanii, Dicranum majus, Dicranum scoparium, Fissidens adianthoides, Racomitrium lanuginosum, Calliergonell cuspidatum, Ctenidium molluscum, Hylocomium splendens, Hypnum callichroum, Hypnum cupressiforme, Palustriella commutatum, Plagiothecium denticulatum, Plagiothecium undulatum, Pleurozium schreberi, Ptilium crista-castrensis, Rhytidiadelphus loreus, Rhytidiadelphus squarrosus, Rhytidiadelphus triquetrus, Sanionia uncinata, Scorpidium revolvens, Thuidium tamariscinum, Atrichum undulatum, Polytrichastrum alpinum, Sphagnum capillifolium, Sphagnum fallax, Sphagnum girgensohnii, Sphagnum palustre, Sphagnum russowii, Sphagnum squarrosum, Sphagnum subnitens, Sphagnum teres, Barbilophozia barbata, Chiloscyphus polyanthos, Diplophyllum albicans, Lophocolea bidentata, Plagiochila porelloides, Ptilidium ciliare, Scapania undulata, Cladonia squamosa, Peltigera canina, Angelica sylvestris, Caltha palustris, Hieraclium spp., Saussurea alpina, Solidago virgaurea, Campanula rotundifolia, Succisa pratensis, Valeriana officinalis, Rhodiola rosea, Vaccinium vitis-idaea, Thymus praecox, Epilobium anagallidifolium, Dactylorhiza viridis, Euphrasia officinalis, Rhinanthus minor, Oxalis acetosella, Oxyria digyna, Polygonum viviparum, Rumex acetosa, Anemone nemorosa, Ranunculus acris, Thalictrum alpinum, Alchemilla alpina, Alchemilla glabra, Filipendula ulmaria, Geum rivale, Galium boreale, Galium saxatile, Saxifraga aizoides, Saxifraga hypnoides, Saxifraga oppositifolia, Saxifraga stellaris, Viola riviniana, Agrostis canina, Agrostis capillaris, Anthoxanthum odoratum, Deschampsia cespitosa, Deschampsia flexuosa, Festuca ovina, Festuca rubra, Nardus stricta, Dryopteris dilatata, Phegopteris connectilis

MG10 — Coastal floodplain grazing marsh, Hard cliff and cliff slope, Upland rush pasture

Holcus lanatus-Juncus effusus rush-pasture

Carex hirta, Carex panicea, Juncus articulatus, Juncus effusus, Juncus inflexus, Calliergonell cuspidatum, Kindbergia praelonga, Angelica sylvestris, Oenanthe crocata, Caltha palustris, Cirsium arvense, Cirsium palustre, Pulicaria dysenterica, Senecio aquaticus, Taraxacum officianalis, Myosotis scorpioides, Cardamine pratensis, Cerastium fontanum, Silene flos-cuculi, Stellaria alsine, Equisetum arvense, Equisetum palustre, Lotus pedunculatus, Trifolium pratense, Trifolium repens, Vicia cracca, Iris pseudacorus, Mentha aquatica, Plantago lanceolata, Plantago major, Polygonum hydropiper, Rumex acetosa, Rumex conglomeratus, Rumex crispus, Rumex obtusifolius, Primula vulgaris, Ranunculus acris, Ranunculus repens, Filipendula ulmaria, Potentilla anserina, Urtica dioica, Agrostis capillaris, Agrostis stolonifera, Alopecurus geniculatus, Alopecurus pratensis, Anthoxanthum odoratum, Cynosurus cristatus, Dactylis glomerata, Festuca rubra, Festulolium loliaceum, Glyceria fluitans, Holcus lanatus, Lolium perenne, Phalaris arundinacea, Phleum pratense, Poa pratensis, Poa trivialis, Schedonorus pratensis

MG12 — Coastal floodplain grazing marsh, Hard cliff and cliff slope

Festuca arundinacea grassland

Atriplex portulacoides, Carex distans, Carex nigra, Carex otrubae, Eleocharis uniglumis, Juncus acutiflorus, Juncus articulatus, Juncus gerardii, Juncus inflexus, Juncus maritimus, Kindbergia praelonga, Odontites verna, Oenanthe crocata, Oenanthe lachenalii, Torilis japonica, Cirsium arvense, Hypochaeris radicata, Scorzoneroides autumnalis, Sonchus arvensis, Taraxacum officianalis, Tripleurospermum maritimum, Cerastium fontanum, Stellaria media agg., Atriplex hastata, Equisetum palustre, Lathyrus pratensis, Lotus corniculatus, Trifolium pratense, Trifolium repens, Vicia cracca, Iris pseudacorus, Triglochin maritimum, Triglochin palustre, Plantago lanceolata, Plantago major, Plantago maritima, Rumex crispus, Glaux maritima, Ranunculus acris, Potentilla anserina, Galium palustre, Agrostis capillaris, Agrostis stolonifera, Anthoxanthum odoratum, Arrhenatherum elatius, Cynosurus cristatus, Dactylis glomerata, Elytrigia atherica, Elytrigia repens, Festuca rubra, Holcus lanatus, Lolium perenne, Phragmites australis, Poa pratensis, Schedonorus arundinaceus, Schedonorus pratensis