Brougher Mountain Biodiversity Profile
In the following account of this LCA it should be noted that for consistency, the biodiversity section follows a standard order for all LCAs even though some of the communities discussed later may have more importance for biodiversity than those discussed earlier.
Key Characteristics
- woodlands cover c. 4% of the LCA of which three-quarters is coniferous forests
- broadleaved and mixed woodland is limited in extent and confined to either present and former estates or to birch dominated woodland on cut-over bog or stream sides
- grassland covers four-fifths of the LCA (compared with around 71% for Northern Ireland), about 70% of which is improved grassland of generally low biodiversity
- acid grassland has developed predominantly on cut-over peat or peaty soils, mainly in the uplands; generally of low biodiversity, this can be increased where there is variation in the depth of peat left by cutting and consequent variation in wetness
- blanket bog is widespread on the spinal upland of this LCA, but as a result of past cutting, drainage and afforestation, less than 4% was described as intact bog in the 1980s; significant stretches of intact bog have been affected by more recent mechanized peat cutting
- examples of relatively rare mesotrophic and eutrophic lake types
- rivers with Priority Species - river water-crowfoot and white-clawed crayfish
Woodlands
Woodlands cover c. 4% of the LCA of which three-quarters is coniferous forests. Large forests are concentrated in the uplands between Brougher Mt. itself and Mullaghnahush, whereas to the east several smaller plantings comprise outliers of Knockmany Forest. To the west there are also isolated plantations, most of which are parts of Pubble Forest. Sitka spruce is the most common tree species, but lodgepole pine, Norway spruce and Japanese larch are also frequent. Most of the large forests have been planted on cut-over blanket peat, sometimes extending onto humic mineral soils, and generally are of low biodiversity.
Broadleaved and mixed woodland is limited in extent. At Knockmany, the Cecil Demesne in 1833, there are modern small compartments of oak and of mixed hardwoods (beech, ash, sycamore and oak), but most of the broadleaved and mixed woodland there falls into LCA 17. Although the present trees are modern planting, many of the compartments, as for example those in Lumfords Glen, occupy sites already woodland in 1833 and therefore may contain species not present in woodlands of more recent origin. There is also parkland (lowland woodland pasture and parkland) at Aughentaine, which was not planted by 1833, and at Derrybard where the mixed planting was new in 1833. Aughentaine has a range of both broadleaved and conifer species that includes oak, horse chestnut, beech, ash and specimen firs; there is also conifer plantation; birch and willow occupy wetter sites. Woodland at Derrybard is extensive and includes that around the former house, but there is a larger stretch on the north facing slopes to the south. This is largely broadleaved, including ash, beech and oak, but there are some intermixed conifers. In parts, cherry laurel and snowberry dominate the understorey with a relatively poor herb layer, but where these shrubs are absent it is more diverse and ferns and bryophytes are abundant.
Outside of these present and former demesnes, broadleaved woodland is dominated by birch. On relatively dry cut-over bogs it forms almost pure stands, but on the wetter edges of bogs it is associated with willow and alder in wet woodland. Birch is also associated with hazel in small hillside and valley woodlands which, when not heavily grazed, can have a diverse herb layer and abundant mosses and lichens. Wet woodland may also be found around the edge of some of the loughs.
Grassland and Arable
Grassland covers four-fifths of the LCA (compared with around 71% for Northern Ireland), about 70% of which is improved grassland; the remainder is acid grassland that has developed predominantly on cut-over peat or peaty soils. These large expanses of upland acid grassland - which also occurs on cut-over lowland peat - have limited biodiversity interest and are often dominated by mat grass or purple moor grass, or towards the margins of the peat, by rushes. However, in some areas of past cutting, islands of deeper peat may be left in the grassland with species more typical of the blanket bog, such as common heather and cotton sedges. The acid grasslands are also, together with the peatlands, important for wetland birds, including snipe and curlew.
Improved pastures generally have low biodiversity as a result of relatively intensive management. Some of the pastures are sown grasslands dominated by ryegrass and few other species - low biodiversity is in-built. Other grasslands have been converted to improved pastures through management. High levels of grazing or repeated cutting for silage, high inputs of fertilizers and slurry, and selective herbicides serve to reduce diversity of both flora and fauna. Arable land is insignificant in this LCA.
Biodiversity in areas of improved pastures and arable is often concentrated in hedgerows. Indeed, they may be the most significant wildlife habitat over much of lowland Northern Ireland, especially where there are few semi-natural habitats. Hedgerows are a refuge for many woodland and farmland plants and animals. In this LCA, field boundaries in those lowlands dominated by improved pastures have dense hedges with mature trees of ash, oak and beech. On the lower slopes boundaries are varied with locally occurring sandstone walls, earth banks with gorse, and low hedges, generally poorly maintained. Recent reclamation has extended improved pastures to higher elevations and the amalgamation of smaller fields has resulted in the loss of even the poor lines of gorse and scrub that previously existed.
Heaths and Bogs
Blanket bog is confined in Europe to the northwest margins of the continent, so that Northern Ireland contains not only a large proportion of the UK's and of Ireland's total area of blanket bog, but also is of major importance at a European scale. Blanket bog, and particularly intact blanket bog, in any LCA is therefore of national and international significance. It is home to plant species adapted to the acidic, low nutrient conditions - including common heather, cross-leaved heath, cotton sedges, bog asphodel, deer sedge, bog mosses (Sphagnum species) and sundews. It is also important for over-wintering birds like the Greenland white-fronted goose, and for breeding birds, including waders. Blanket peat is also important as a store for carbon and as a repository of information on past environments.
Blanket bog is widespread on the spinal upland of this LCA, but as a result of past cutting, drainage and afforestation, less than 4% was described as intact bog in the 1980s. This was in three relatively large areas - in or near Ramaley, Meenawanick and Stranisk Townlands. Unfortunately, the advance of mechanised peat cutting through the 1980s and 1990s has resulted in the loss of most of these three areas. Unlike past hand-cutting, mechanised cutting often leaves the peat bare or at best dominated by one or two species such as cotton sedge or deer sedge; the bog mosses and many of the other plants take many years to re-colonise. Although the intensity of cutting has declined in recent years, some relatively large sites remain active and on presently abandoned sites the slow recovery of the vegetation gives a low species diversity.
Cut-over bog that results from past hand cutting, has importance to biodiversity; it can have various depths of peat with different vegetation and different levels of water, including old turf pools. As a result, there is a range of micro-habitats for insects, including water-beetles and dragonflies. In addition to the spread of mechanised cutting onto cut-over bog in the recent past, forestry has also reduced the area and biodiversity of former cut-over bog.
The large extent of cut-over blanket peat includes not only acid grasslands (see above) but also relatively deep peat which has a dominance or abundance of common heather. Such areas have the appearance of wet upland heathland, but most are strictly blanket bog because they have more than the 50cm depth of peat that is the limit for heathland. The heather cover, along with the varied vegetation of the cut-over bogs, provides habitats for several bird Priority Species, including red grouse, curlew and skylark.
There is no intact lowland raised bog in the LCA, all has been cut-over in the past, but the bogs provide habitats for breeding lapwing, curlew and snipe, as well as for invertebrates - in the same way as cut-over blanket bog.
Wetlands and Lakes
The largest lake in this LCA to be surveyed by the Northern Ireland Lake Survey was Ballydoolagh Lough. This was classed as an example of mesotrophic lakes (i.e of middle range of nutrients) of the 'Nymphaea/Fontinalis/Littorella' type - these are relatively base and nutrient poor lakes developed naturally in sandstones. Watsons Lough was also classed as mesotrophic. Mesotrophic lakes potentially have the highest macrophyte diversity of any lake type. Furthermore, relative to other lake types, they contain a higher proportion of nationally scarce and rare aquatic plants. This is an increasingly rare type of lake in Northern Ireland and the UK generally because the nutrient status of many is being increased through input of water from agricultural land that has had applications of fertilizers and slurry.
Largy Lough is an example of eutrophic standing waters, of the 'Nuphar/Elodea/Potamogeton alpinus' type. This is a natural lowland lake type with elements of the more mid-altitude aquatic macrophyte floras. Compared with many lowland lakes, this type is relatively un-enriched; it is a comparatively rare type, with a Fermanagh / South Tyrone bias. Killee Lough is a marl lake of the 'Nuphar/Elodea/Chara/Algae' type - small, clear-water, un-enriched lakes with relatively high base status, and usually related to limestone areas. Marl lakes, generally rare in Northern Ireland are most common in Fermanagh.
Fens are not common in this LCA, generally restricted to the margins of lakes as at Ballydoolagh, Derrin, Killee and Largy. Reedbeds are also of restricted occurrence; examples include those at Killee Lough and Largy Lough. The Irish damsel fly and the marsh fritillary butterfly are found at Ballydoolagh Lough, Watson's Lough and Killee Lough.
The Tempo River has river water-crowfoot and the white-clawed crayfish; the latter is also present in the Manyburns River. The otter is quite common throughout the area.
Key Issues
General actions for UK and NI Priority Habitats and Priority Species are detailed in the Habitat Action Plans and Species Action Plans.
WOODLANDS
Issue: low woodland cover of variable biodiversity value
Actions:
- enhance the biodiversity value of demesne/parkland woodland through control of grazing and felling; by encouraging planting of saplings of the standard trees; by preventing further loss of parkland; by retention of fallen and veteran trees (particularly for bryophytes, ferns, fungi and fauna)
- further study of the history and ecology of demesne and other broadleaved woodlands particularly any ancient and long-established, as a key to future management
- encourage control of grazing in broadleaved woodlands along streams to foster regeneration and if necessary, encourage replanting of canopy species
- consider removal of conifers from 'coniferized' former broadleaved and mixed woodlands, especially those that are 'long-established'
- encourage planting of native broadleaved woods rather than the small conifer plantations which are of poor biodiversity and landscape value
- retain colonizing woodland on former cut-over bogs
GRASSLAND AND ARABLE
Issue: poor biodiversity of farmland
Actions:
- maintain and improve field boundaries - especially hedgerows in lower land. This may be achieved through adoption of correct cutting cycles; hedge laying and replanting where necessary; leaving saplings uncut to develop into hedgerow trees; avoidance of spraying with fertilizers, slurry, herbicides; provision of wildlife strips and conservation headlands around fields; and limitation of field amalgamation.
- encourage (through participation in Environmental Schemes) adoption of less intensive management of pastures to allow reversion to more species-rich grassland and protect unsown areas of species-rich grassland
- promote further research on the biodiversity of upland acid grassland as a guide to future management
HEATH AND BOGS
Issue: blanket bogs in Northern Ireland are of national and international importance, but intact bog is now rare in this LCA
Actions:
- consider restoration of blanket bog habitats - especially those formerly intact but affected by recent mechanized peat extraction - through appropriate water level management and phasing out peat cutting
- prevent new forest planting on blanket bog, especially that which could be restored to active growth
- monitor use of cut-over blanket bog to ensure that the important micro-habitats are not lost, that the large tracts of land required by predator birds are not broken up by planting and other uses, and that the needs of over-wintering and breeding wetland birds are met
- ensure that the cover of heather (and of different ages) is retained not only for the plant biodiversity, but also as habitats for red grouse and other Priority species
WETLANDS
Issue: important examples of relatively rare types of mesotrophic and eutrophic lakes and rivers with Priority Species
Actions:
- protect water quality of lakes and rivers through nutrient management, thus
- promote and encourage existing good farming practices so that streams are not polluted by run-off from agricultural land or seepage from silage pits
- monitor streams in relation to expansion of rural housing and associated septic tanks/sewage treatment plants
- protect lakes and rivers from sediment deposition, particularly associated with peat extraction in the uplands
