Site Code
Country: United Kingdom
Central coordinates: 49.91666667o [49o 55' 0" North], -6.33333333o [6o 19' 59" West]
Administrative region: South West (West Cornwall)
Area: 566 ha
Altitude: 0 - 23
Site Description
This IPA has been identified for its coastal and maritime heath bryophyte and lichen communities though is comprised of several component parts each with a unique identity.
Botanical Significance
Bryophytes (coastal heaths) Sphaerocarpos michelii, Riccia cristallina, Zygodon forsteri, Lophocolea semiteres, Fossombronia foveolata.
Lichens (Rock cliffs, ledges and shores, including the supralittoral: coastal rocks and Temperate shrub heath: coastal rocks) Catillaria subviridis, Ramalina chondrina, Ramalina portvensis, Teloschistes flavicans, Acarospora subrufula, Pseudocyphellaria aurata, Lobaria pulmonaria, Heterodermia sp., Caldonia sp.
This IPA has been identified for its bryophyte and lichen interest though is comprised of several component parts each with a unique identity and community;
Annet is the largest uninhabited island on the western side of the Isles of Scilly archipelago.. The island is low lying, reaching a maximum
altitude of 18 m and is consequently much exposed to the effects of wind and salt spray. This exposure has restricted species diversity and only 53 species of vascular plant have been recorded on the island. The exposed granite carns and boulder beaches support a variety of rare maritime lichen species including Roccella fuciformis.
Wingletang Down forms an extensive area of low lying unenclosed heathland, dune grassland and rocky coast on the south side of St Agnes, an inhabited island in the south western part of the Isles of Scilly archipelago. Maritime heathland covers much of the site and supports populations of a number of rare plant species including the bryophytes Sphaerocarpos michelii, Riccia cristallina, Zygodon forsteri.
Gugh is a small inhabited island connected to the east side of St Agnes by The Bar, a
sandy tombolo. The maritime heath is rich in rare lichen species including Lobaria pulmonaria and Teloschistes flavicans.
Peninnis Head forms a prominent cliffed headland on the south side of St.
Mary’s on the south eastern margins of the Isles of Scilly archipelago.
The extreme oceanic conditions experienced at Peninnis Head have encouraged the development of a rich lichen flora on cliff, tor and heathland habitats. Ramalina siliquosa occurs extensively and Roccella fucoides and Teloschistes flavicans are two particularly rare species that occur here.
Pentle Bay is situated on the south-eastern side of the island of Tresco, exhibiting an important transition from dunes to lichen-rich healthland. This heathland offers a suitable substratum for an outstanding lichen flora, including a range of rare oceanic species. These include the nationally rare Heterodermia leucomelos and Pseudocyphellaria aurata. In addition and very unusually Lobaria pulmonaria and L. scrobiculata dominated communities are found growing on Heather. There are few analogous sites in Europe for the type of lichen-heath associations found on this site and other parts of Scilly. The heath also supports a number of bryophytes, including the nationally rare liverwort Lophocolea semiteres and the nationally scarce liverwort Fossombronia foveolata.
Shipman Head forms the north end of the island of Bryher on the north-western margins of the Isles of Scilly archipelago. Shallow podzolic soils and the extreme maritime exposure have led to the development of maritime heathland containing some rare lichen species such as Lobaria pulmonaria and Teloschistes flavicans.
Castle Down is an exposed headland on the north side of the island of Tresco on the
northern margins of the Isles of Scilly archipelago. This extreme maritime exposure and the thin podzolic soils have resulted in the development of an extensive area of ‘waved’ maritime heathland with a particularly important lichen flora, exhibiting a range of rare oceanic heathland species including the only known European record of Heterodermia propagulifera together with H. leucomelos and H. obscurata. These Heterodermia communities are now very rare and comparable sites, outside Scilly, only occur in Brittany and Channel Islands. The 45 species of lichen recorded also include Lobaria pulmonaria growing on Calluna vulgaris and a number of Cladonia species dominating the shallow soils and open pans on the central heathland.
Plains and Great Bay is of importance for illustrating the classic succession of coastal communities from embryo dunes to dune scrub. In terms of lichen interest, the Calluna vulgaris, Erica cinerea and Ulex gallii dominated heath has a conspicuous Cladonia sp. dominated ground flora.
Other areas such as Rushy Bay and Heathy Hill (Bryher), Samson, Big Pool, parts of ST Marys Island, Porthloo, White Island and Chapel Down are all thought to be of importance for their lichen interest though their species composition is not known.
Possible new species of Heterodermia (propagulifera) to Europe on Isles of Scilly?
Additional vascular plant interest of IPA: Flora includes some species not found elsewhere in Britain (other than Channel Isles) or that are very rare on mainland. Arable plant communities associated with growing winter-flowering narcissus are probably unique (and threatened). Species identified in IPA through BSBI consultation: Allium ampeloprasum,
Anagallis minima,
Arum italicum ssp. neglectum,
Asplenium obovatum,
Baldellia ranunculoides,
Briza minor,
Calystegia sepium ssp. roseata,
Chamaemelum nobile,
Chenopodium murale,
Chrysanthemum segetum,
Cuscuta epithymum,
Cytisus scoparius ssp. maritimus,
Daucus carota ssp. gummifer,
Filago vulgaris,
Fumaria occidentalis,
Limosella aquatica,
Medicago polymorpha,
Misopates orontium,
Oenanthe fistulosa,
Ophioglossum azoricum,
Ophioglossum lusitanicum,
Ornithopus pinnatus,
Polycarpon tetraphyllum,
Polygonum maritimum,
Radiola linoides,
Rumex rupestris,
Salsola kali ssp. kali,
Scandix pecten-veneris,
Scilla autumnalis,
Sibthorpia europaea,
Spiranthes spiralis,
Trifolium glomeratum,
Trifolium occidentale,
Trifolium suffocatum,
Vicia bithynica,
Viola kitaibeliana,
Zostera marina
Management guidance notes
Component sites: Wingletang Down , St. Mary's, Annet , St Agnes, Gugh, Bryher, Tresco , St. Martins
Notes
None