In the following account of this LCA it should be noted that for consistency, the biodiversity section follows the standard order for all LCAs even though some of the communities discussed later may have more importance for biodiversity than those discussed earlier
Key CharacteristicsWoodlands account for around 7% of the land cover of the LCA, almost all in coniferous forest. Most of the coniferous forests are State Forest, but the notable exception is Batt Wood. This is a large plantation clothing the western slopes of Altataggart Mountain in Scots pine, larch and spruce. It is irregular in outline due to sporadic felling but can be broadly divided into the larger upper part (continuous for approximately 2km), a more discontinuous lower part and a band of scattered Scots pine and laurel beside the river. In addition to sporadic felling, there are several locations of severe windblow and no evidence of replanting.
Rostrevor Forest extends 8km on the west facing slopes of the Mournes above the Kilbroney valley. Planting is complex and although there are patches of mixed hardwoods, conifers predominate - in particular Sitka spruce, Douglas fir and European larch. Donard Forest is equally complex, especially in the northern part where intertwined stands of Scots pine, noble fir and lodgepole pine are most frequent. In the centre there is considerable mixed planting of beech and Scots pine whereas in the southern section Scots pine and lodgepole pine dominate. Other, smaller conifer forests or parts of forests crossing the LCA boundary occur; Scots pine, larch, noble fir, Sitka spruce and Corsican pine are the most common species.
The main broadleaved woodland is Rostrevor Wood ASSI (and NNR), a mature oak woodland (Upland oakwood) at least 250 years old and possibly an ancient woodland. The dominant woodland type occurs on the upper, freely draining acidic slopes. The dense canopy of oak has an understorey of hazel and occasional holly with bramble, honeysuckle, bilberry and carpets of greater wood-rush below. The lower slopes are flushed and mildly base-rich resulting in the presence of ash; the ground flora is typically more diverse. The woodland flora includes rare plants such as wood fescue, toothwort and bird's-nest orchid. Nationally scarce species of lichen have been recorded including Melaspilea granitophia, a record new to Ireland. Invertebrate sampling has recorded important hoverflies and houseflies.
Grassland and ArableImproved grassland, because of the upland character of this LCA, is rare; indeed only small patches are clipped by the LCA boundary. Rough grassland therefore comprises almost all of the 43% of the land cover that is grassland. It is acid grassland often dominated by mat grass with common bent, sheep's fescue, sweet vernal grass and heath bedstraw. These grasslands frequently form complex mosaics with dwarf shrub heaths, often indicating the degradation and fragmentation of former heath habitat as a result of persistent sheep grazing. Small pockets of Upland calcareous grassland, rare in eastern Northern Ireland, with species such as wild thyme, and wet acid grasslands dominated by purple moor-grass, rushes and sedges provide additional habitat diversity.
Heaths and BogsThe Mournes support some of the most extensive tracts of Upland heathland in Northern Ireland, one of the reasons for their conservation designations Eastern Mournes ASSI (and SAC). The dominant species are common heather and bell heather, the dominance of the latter being unlike similar communities in GB and reflecting the more oceanic, mild conditions. However, there is considerable diversity of habitats resulting from variation in physical conditions and land-use history.
The damp microclimate on lower, north-facing slopes allows wet heaths to develop that are characterised by cross-leaved heath, deer sedge, purple moor grass, carnation sedge and bog mosses. The rare northern Atlantic moss silky swan-necked moss (Campylopus setifolius) is abundant in this community.
There are also communities associated with springs and flushes; for example, black bog-rush dominates some vegetation in acid and neutral flushes and moss communities around springs include those dominated by Fountain Apple-moss (Philonotis fontana) which may have the scarce starry saxifrage present.
Montane heath is restricted in Northern Ireland to the highest mountains; in the Mournes it is often dominated by grasses such as sheep's fescue and bents with mounds of woolly hair moss (Racomitrium lanuginosum). This moss was probably once more widespread but is now confined in its distribution to those areas of light grazing. The rare alpine clubmoss (Diphasiastrum alpinum) is locally frequent and on the tightly grazed sward on the summit of Slieve Donard there is abundant dwarf willow, a scarce montane species.
On the eastern side of the LCA, upland heaths grade into lowland heathland, notably in the Bloody Bridge Valley. Whereas there is no major change in the flora, this is a major site for lowland heath fauna including the leaf-footed bug in its only known Irish site, hoverflies and the tiger beetle as well as large populations of the butterflies the dark green fritillary and the grayling.
Much of the heathland has been affected by past and recent grazing; not only have heather dominated communities been reduced to coarse grassland (see Grasslands above), but much of the remaining heather is diminished in height and spread and there is an increase in bare ground, especially on some of the steeper slopes.
In addition to the heathland communities, and sometimes grading into them, there are expanses of blanket bog in the Mournes. Northern Ireland has a high proportion of the UK and Ireland total areas of this nationally and internationally important habitat that in Europe is confined to its north-western margins. However, very little of the blanket bog in the Mournes remains intact, most has been eroded and is thin and other areas of deeper peat have been cut-over or indeed cut-away. For example, the Bog of Donard is largely eroded, and Red Bog, Kilbroney Red Bog and Castle Bog are all cut over, as are large parts of the surrounds of Spelga Dam. Remnants of intact bog are small and found at Kilbroney Red Bog (one of the two known NI sites of the few-flowered sedge), Castle Bog and at the Rowan Tree River.
Upland heathlands and blanket bogs are important habitats for upland birds, including the rare ring ouzel and red grouse as well as invertebrate communities. The montane heaths support one of the largest assemblages of montane invertebrate species recorded in Ireland; species include predatory ground beetles Notiophilus aesthuans and Miscodera arctica and the sawfly (Pontania crassipes ) that feeds on the dwarf willow. Slieve Donard is the only known Irish site for these three species.
Wetlands and LakesTwo reservoirs (Silent Valley and Ben Crom) and a number of base-poor, upland lakes occur within the mountain range. The natural water bodies have clear waters and are generally devoid of aquatic plants. Exceptions include Binnian Lough and Blue Lough, which are characterised by the presence of quillwort and water lobelia. The marginal vegetation associated with these water bodies tends to be sparse and restricted to a swamp and poor acid fen fringe. Nevertheless, there are some uncommon upland invertebrates including the beetle Potamonectes griseostiatus and the water bug Glaenocorisa propinqua.
The Mournes are the source of many rivers, but few have records of Priority Species. The White Water has river water crowfoot and the otter and keeled skimmer is present in others.
CoastalIn the east of the LCA the coast consists of semi-natural cliffs with a rocky shore and shingle communities below. The coastal vegetated shingle between William's Harbour and Green Harbour is of note because it the best example in Northern Ireland of a habitat which is poorly represented here. Good populations of yellow-horned poppy and oyster plant are found. Lower cliff slopes are flushed with base-rich water to give species-rich communities of purple-moor grass and black bog-rush (a National Trust site)
.To the west of the LCA, the shore north of Killowen is of fucoid dominated boulders of low floral diversity but good faunal diversity under the boulders.
Key IssuesGeneral actions for UK and NI Priority Habitats and Priority Species are detailed in the Habitat Action Plans and Species Action Plans.
WOODLANDSIssue: maintenance of woodland diversity
Actions:
Issue: extensive and extending upland rough grassland at the expense of heather heath
Actions:
Issue: maintenance of one of the most extensive areas of upland heath in Northern Ireland, particularly of heather-dominated communities
Actions:
Issue: maintenance of rare montane communities
Actions:
Issue: maintenance of the few small areas of intact blanket bog remaining
Action:
Issue: maintenance of water quality of rivers and lakes
Action:
Issue: LCA includes the best example of coastal vegetated shingle in Northern Ireland
Action: