|IPA Factsheet - Eigg|
Site Description From SSSI Citation: The Isle of Eigg is in the inner Hebrides, lying 10 miles off the Scottish west coast, south of the Isle of Skye. Eigg is exceptionally diverse for a small island, with coast, unimproved farmland, willow and hazel scrub, native woodland, raised bog and moorland. The centre of the island is a moorland plateau, rising to 393 m at An Sgurr, a dramatic pitchstone ridge, sheer on three sides.
Botanical Significance Noted for lichens and vascular plants interest. (From SSSI management statement). At the foot of the cliffs of Beinn Buidhe, the steeper slopes are covered with hazel scrub, a scarce woodland type in Lochaber. Intermixed with the hazel are occasional wych elm, rowan and aspen and thickets of blackthorn. The wood shows few signs of disturbance and has a ground flora comprising a wide range of woodland species of which ramsons Allium ursinum and enchanterís-nightshade Circaea lutetiana are particularly abundant. The diversity of lichen species found growing on the trees forms a nationally important assemblage which includes white script lichen Graphis alboscripta and Pseudocyphellaria norvegica. Small areas of hazel scrub, with occasional blackthorn and aspen, occur along the east coast. These areas have a rich ground flora containing many spring flowering herbs such as wild hyacinths Hyacinthoides non-scripta, ramsons Allium ursinum and primrose Primula vulgaris. These areas of scrub woodland represent remaining fragments for a woodland type once widespread in the west of Scotland. At Struidh the scrub supports an outstanding lichen assemblage which comprises western oceanic epiphytic species, including rare ones, and is indicative of antiquity and lack of disturbance. Eigg, along with Rum and Skye, is an important site for Eyebright Euphrasia spp on basalt (ultra-basic) coastal turf, saltmarsh and montane habitats. Species include: Euphrasia heslop-harrisonii, E. scotica, E. ostenfeldii, x electa, E. frigida, northern limit of E. tetraquetra, E. nemorosa, E. arctica (complex between two) and E. foulaensis.
General Habitat Description (From SSSI management statement). The north and east coasts of Eigg are dominated by basalt cliffs, below which are grassy and boulder strewn slopes descending to sea level. The basalt has given rise to fertile conditions which combine with the coastal location to form a predominantly base-rich maritime cliff habitat and woodland; the woodland itself then supports a significant lichen assemblage. Below the basalt the older Jurassic rocks are important for their fossil content and sedimentology. The basalt cliffs and slopes forming the western flank of Beinn Bhuidhe have created base-rich soils which support species-rich grassland, ledge communities, mire and an important assemblage of vascular plants. On the higher slopes there is an extensive area of hazel dominated scrub, which in turn supports a rich assemblage of lichens.
Conservation Issues The condition of the scrub and the lichen assemblage on the eastern coast of Eigg is considered to be in favourable condition. However, woodland is mainly confined to steep slopes above Struidh (mostly on inaccessible ground) and at Poll nam Partan as grazing by sheep seems to be preventing spread of the woodland onto more accessible ground. Grazing by sheep appears to be preventing spread of the woodland on to more accessible ground. However, although a significant reduction in grazing pressure would likely result in the development of a more extensive area of woodland, this could potentially have a detrimental impact on the lichen assemblage by reducing the amount of light reaching epiphytic lichens on mature trees within the stand. The most recent Site Condition Monitoring (SCM) for the scrub habitat on the slopes of Beinn Buidhe indicated that it was in a favourable condition. However, bushes of a cotoneaster species are frequent at the southern end of the IPA component site and a few mature sycamore trees are also present close to the downslope boundary of the woodland. In time, if these spread, they could adversely affect the site. The woodland supports a diverse lichen flora. SCM results show that the lichen assemblage feature is in favourable condition. Grazing levels and the presence of dense and extensive stands of bracken appear to be severely limiting the growth of tree saplings on open ground adjacent to the woodland. Grazing is primarily by sheep. Although most of this ground has a dense cover of bracken the areas of grass that remain are moderately or heavily grazed. Almost all the well-grown saplings of native tree and shrub species are protected from grazing by a mixture of dense bracken and brambles.