Enniskillen Biodiversity Profile
In the following account 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 just under 10% of the LCA, a relatively high percentage for Northern Ireland (about 5.6%)
- of this, three-quarters is broadleaved or mixed woodland, which is also a much higher proportion than for Northern Ireland as a whole (about a third)
- extensive estate woodland and parkland
- wet woodland is common around the shores of Lough Erne and its islands
- semi-natural mixed ash and oak woodlands on islands and within former estates and State Forest; hazel-ash woodland patches on limestone in the west
- semi-natural grasslands, particularly wet grasslands between drumlins and alongside rivers and shoreline; dry semi-natural grasslands on limestone to the west
- important lakes - mesotrophic, eutrophic and marl lakes - including rare types
Woodlands
Woodlands cover just under 10% of the LCA, a relatively high percentage for Northern Ireland (about 5.6%); of this, three-quarters is broadleaved or mixed woodland, which is also a much higher proportion than for Northern Ireland as a whole (about a third). The high percentage of the land cover is explained by the presence of large estate woodlands and State Forests, and the large proportion that is mixed or broadleaved by planting broadleaves within these. There are, however, extensive compartments of conifers.
Coniferous forest at Castle Archdale is in Bunaninver, Mullies and Glenross where Norway and Sitka spruce are dominant. However, even within the predominantly conifer areas there are oaks and beech. Similarly, in Riversdale Forest there are compartments of pure Sitka spruce, but others where Norway spruce and Scots pine are accompanied by some beech and oak. On the opposite shore of the lough, Ely Lodge Forest is dominated by European larch, but hardwoods are intermixed. In contrast, Lenaghan Wood, to the west of Enniskillen, is of Sitka spruce.
The occurrence of broadleaved trees in the planting, the presence of woodland patches from original estate woodland, adjacent broadleaved woods, and some semi-natural remnants running through the forests, produce a greater biodiversity of the predominantly coniferous parts of the State Forests than for most coniferous forests in Northern Ireland. It is notable that the Forest Service has identified areas for the 'Restoration of native woodland on Plantations on Ancient Woodland Sites (PAWS)' within both Ely Lodge Forest and Castle Archdale Forest.
Large estates with extensive woodlands and parkland are common in this LCA (lowland woodland pasture and parkland). Apart from predominantly coniferous forest at Castle Archdale, there is also some estate woodland. Castle Archdale Country Park is based on the Archdale Manor House; the original house dates to 1615 and the demesne may therefore contain woodland elements that are 'long established' (pre-date the 1830s) and may be 'ancient' (before 1600AD) - woodlands that may be rare in Northern Ireland and which may contain species not common in more recent woodlands (note the PAWS project above). The present woodlands are characterized by oak and ash with sycamore, beech, horse chestnut and a range of other broadleaves and conifers, including Scots pine. As elsewhere around the lough, there is wet woodland (see below) that adds to the habitat diversity. Interest is also enhanced by several other features, including a red deer enclosure, wildfowl ponds, butterfly garden and wildflower meadow.
Further south around Killadeas Manor - Gublusk there are also estate woodlands with similar tree species to those found commonly at Castle Archdale and other estates in this region. Also there are wet woodlands along the shore and patches of other semi-natural woodlands, including birch and ash woodlands (see below).
The woodlands at Castle Coole (a National Trust property) are mostly mixed deciduous plantations (including oak, ash, beech, sycamore and larch) created in the 18th and 19th centuries, although some may have been established on ancient woodland sites. In general they are of relatively limited floristic interest with exotic species of trees (include western hemlock, common silver fir) and shrubs being locally frequent. The open parkland, with its scatter of mature and over-mature trees, is of high nature conservation value for saproxylic (of dead wood) invertebrates. Other estate woodlands in the south of the LCA include Killyreagh House, Bellevue and Lisgoole Abbey, alongside which is a relatively large oak, ash, sycamore, birch, mixed woodland.
On the west side of the lough, Ely Lodge - Castle Hume forms the most extensive area of estate woodlands. Ash is abundant with beech, oak and sycamore common amongst a wide range of species, but there are also conifer plantations. As with many of the estates, the understorey has rhododendron and cherry laurel dominant in parts, but in other areas hazel, holly and willow are abundant. Where the understorey is more open, the herb layer is quite diverse and, in common with other woodlands in the LCA, mosses and lichens are frequent or abundant.
Lower Lough Erne was lowered in the 1950s exposing new land along the shore of both the lough margins and of the islands; this has been colonised by natural scrub of alder and willow to give extensive tracts of wet woodland sometimes within a complex of a swamp/fen/carr. Frequently, the alder-willow woodland is succeeded by young ash woodland that merges into more mature ash woodland or estate woodland on the former shoreline, as for example at Gublusk Bay. Similarly, Inish Lougher and Inish Divann are characteristic of islands that have a foreshore of alder - ash woodland.
The islands themselves are varied in their woodland cover. In parts there is ash - mountain ash woodland, as at Inish Lougher, whereas others have oak - birch woodland as on Inish Divann, Long Island and Inish Free. However, some of the islands show evidence of planting, with scattered conifers and exotic broadleaves. Castle Archdale Islands NNR consists of three islands, Iniskmahill, Cleenishmeen and Cleenishgarve that provide examples of relatively undisturbed mixed deciduous woodland on glacial drift in the Lower Lough Erne basin. The relatively unspoilt woodland on these islands is a mixture of many species including oak, yew and ash. Willow and hazel form the understorey. The diversity of the herb layer varies from good to poor, depending on the amount of grazing - in addition to cattle some of the islands have grazing by goats that reduce the herb layer.
On the west side of the LCA, hazel woods and upland mixed ashwood form small woodland patches alongside streams and on the slopes, which in contrast to the eastern side of the lough where soils are derived from Old Red Sandstone till, are covered by thin limestone soils or deeper soils derived from limestone till. Some of these patches have a moderately diverse herb layer, but the diversity and cover depends partly on the extent of grazing.
Birch woodland is quite common on areas of dry peat; for example, to the east of Glenross on cut-over peat, birch is mixed with mountain ash and ash. Wetter parts of cut-over bogs often have alder-willow dominated wet woodland. On the west of Rossfad Hill, extensive birch woodland has beech, oak and ash commonly occurring. The wood has a rather poor species composition that includes stands of rhododendron scrub.
Grassland and Arable
Grasslands cover about 58% of the LCA, a relatively low percentage compared with Northern Ireland as a whole (c. 71%) but explained by the percentage occupied by the lough; if the lough is excluded, then grassland accounts for three-quarters of the land cover, most of which is improved pasture. This generally has 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 hedges tend to be overgrown and gappy, although with many hedgerow trees, and to fulfil their role in providing habitats for flora and fauna require management.
Semi-natural and less improved grasslands are associated with damp areas between drumlins and alongside rivers, particularly to the west and south of Enniskillen, where they often merge with fen - for example the fen-meadow around Mill Lough (purple moor grass and rush pastures). In addition there are wet grasslands on the shoreline of islands and around the margins of the lough. These grasslands show a gradation from those that are frequently inundated and species-rich (with common sedge, star sedge, and the grasses - red fescue, creeping bent, sweet vernal grass) to mesotrophic grasslands, also species-rich and of the crested dog's-tail - knapweed type (with carnation sedge, flea sedge, glaucous sedge and the grasses - common quaking grass, red fescue, Yorkshire fog, sweet vernal grass). Damp grasslands on the islands are particularly important for wetland birds; for example on Devenish Island, Humphrey's Island and Horse Island ASSI. The last is a lightly-grazed drumlin island dominated by sharp flowered rush, with a variety of grasses and sedges and in places is quite species rich. Over 60 pairs of waders including snipe, curlew, redshank and lapwing, have been recorded breeding on the island, making it one of the most important sites in Northern Ireland. Other breeding birds include common sandpiper, oystercatcher, great crested grebe and tufted duck.
In contrast to most semi-natural grassland, Beagh Big ASSI is relatively dry and dominated by grasses with red fescue, Yorkshire fog, perennial ryegrass and crested dog's-tail all achieving high cover values. Yellow oat-grass is frequent. There is an abundance of herbs such as bulbous buttercup, yellow rattle, red clover, knapweed and lady's bedstraw. Several rare or locally significant plant species occur, including adder's-tongue fern and cowslip.
Although the area of improved grassland is large, the closeness of the lough with its varied habitats, the presence of woodlands, damp grasslands, lakes and bogs, have provided habitats for a wide range of bird Priority Species within the farmland, including bullfinch, linnet, reed bunting, skylark, song thrush and spotted flycatcher.
Heaths and Bogs
There is little lowland raised bog in the LCA; it is confined to a few patches on the east side of the lough between Castle Archdale and the outskirts of Enniskillen, and in the extreme south. Almost all have been cut-over; a small intact strip remains to the east of Rockfield, but is of no great biodiversity interest.
Wetlands and Lakes
The LCA has a wealth of lakes, many of which belong to rare types of mesotrophic and eutrophic lakes.
Lower Lough Erne is one of the largest water bodies in Northern Ireland and is recognised not only for the quality of its landscapes, but also for its fish and bird life as well as for the diversity of its shoreline communities (reedbed, fen, wet woodlands). For example at Gublusk Bay the emergent vegetation that occurs along the shallows and shoreline are predominantly formed by a mixed reed-canary grass and yellow iris swamp, but there are also a few localised pockets of reed-canary grass and common-spike rush swamp in open water that back onto a mixed yellow iris fen long the shoreline. In other parts of the lough and island shorelines, common reed or club rush or tufted sedge may be dominant.
The lough has an international reputation in angling and in addition to common species, Lower Lough Erne is one of only two sites in Northern Ireland for pollan (the other is L. Neagh). The Lower Lough Erne Islands are especially important for birds (several islands included in the RSPB Lower Lough Erne Islands Reserve). Breeding birds on the islands include snipe, redshank, curlew, lapwing, dunlin and sandwich terns. In winter, whooper swans, greylag geese and ducks, including widgeon, pochard and tufted duck, may be seen on the Lough.
Despite the quality of its water, the Lough is sensitive to eutrophication; the Erne Nutrient Management Scheme aims to improve the quality of water in tributary rivers, by limiting phosphate losses from agricultural sources. Similarly, there are potentially competing interests in the wildfowl, but local action is seeking to mitigate possible conflicts between wildfowlers and the demands of conservation.
Upper Lough Erne SAC is a very large eutrophic lake (some of which is included in the south of the LCA) situated in a drumlin landscape and has a predominantly limestone catchment. The SAC is an example of a northern or western eutrophic lake of glacial origin in Northern Ireland. The lake has a very long shoreline and numerous associated satellite lakes, many of which are included in the SAC. Both club-rush - common reed, and reed canary-grass - shoreweed - spike-rush associations are well developed on the shore, showing transitions from reedbeds to swamp and fen vegetation.
This SAC provides representation of the otter in Northern Ireland. The province holds one of the strongest populations of otters in the UK and Upper Lough Erne with its extensive associated wetland habitats holds a dense and large population.
Lough Bresk was the only mesotrophic lake identified by the Northern Ireland Lake Survey as a Priority Habitat. Mesotrophic lakes have a middle level of nutrients between nutrient poor (oligotrophic) and nutrient rich (eutrophic). 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 because the nutrient status of many is being increased through input of water from agricultural land that has had applications of fertilizers and slurry.
Most of the lakes were classed as eutrophic (eutrophic standing waters) and whilst some show moderate enrichment from surrounding land, Loughs Accrussel, Laragh C and Knock were described as of the 'Nuphar/Elodea/Potamogeton alpinus' type - a natural lowland lake type with elements of the more mid-altitude aquatic macrophyte floras. Such lakes are relatively un-enriched compared to other lowland types and are comparatively rare, with a predominantly Fermanagh/S.Tyrone distribution. The LCA also contains some of the rarest lake types - the marl lakes - and within this group, some which belong to the Nuphar/Elodea/Hippuris type - the cleanest, clearest, hard water lakes with the highest base status and most specialised flora. These lakes are not only rare but also vulnerable to phosphate accumulation (Loughs Kinarla, Drumcose, Aleen, Yoan and Mill Lough).
Mill Lough ASSI is notable for its important wetland flora and fauna. It is only one of three water bodies in Northern Ireland with eight species of pondweed, has ten species of dragonfly and significant numbers of waterfowl in winter. It also displays, as do many of the smaller loughs, a well-developed transition from open water, through emergent swamp and fen, to carr woodland or fen meadow.
The LCA also contains the Fardrum & Roosky Turloughs SAC. The three turloughs (Aquifer-fed naturally fluctuating waterbodies) in this group - Fardrum Lough, Roosky Lough, and Green Lough - are the only turloughs in Northern Ireland, and represent the most northerly occurrence of this habitat in Ireland and the UK. All three contain distinctive vegetation communities associated with their inundation zone, including the bryophytes Cinclidotus fontinaloides and Fontinalis antipyretica. In addition, Green Lough supports the nationally rare fen violet and a very rich ground-beetle fauna including the carabids Blethisa multipunctata and Pelophila borealis.
The Ballinamallard River has river water crowfoot and the white-clawed crayfish has been recorded at West Bridge, Enniskillen, Drumnagalliagh and Drumnagreshial River at Shallany Td. The Ballinamallard River (along with the Colebrook) have been undergoing stocking with juvenile salmon as part of a cross-border salmon enhancement initiative for the Erne system.
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: above average woodland cover with some of high 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 Forest Service in its programme to re-establish broadleaves in plantations over ancient woodland sites
- encourage control of grazing in broadleaved woodlands to foster regeneration and if necessary, encourage replanting of canopy species
- encourage planting of broadleaved plantations, through appropriate grant schemes, rather than the small conifer plantations which are of poor biodiversity and landscape value
- monitor the effects of recreation and shoreline development on wet woodlands and island woodlands
GRASSLAND AND ARABLE
Issue: poor biodiversity of farmland, but some grasslands of biodiversity importance
Actions:
- maintain and improve field boundaries especially hedgerows . 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 - both in damp pastures (e.g. fen-meadows) and dry meadows
- protect shoreline grasslands and island grasslands against development and recreational interests, both for their flora and birds
WETLANDS
Issue: fens in Northern Ireland are a large proportion of the UK resource, here there are extensive reedbeds, swamp and fens around both the large loughs and several of the small loughs
Actions:
- protect fens and other wetlands against loss by drainage and infill, which includes use as official refuse tips as well as sites in which to deposit building rubble and fly-tipping.
- leakage of fertilizers and slurry from surrounding agricultural land should be prevented as this increases the nutrient levels and affects species composition
- monitor the effects of shoreline development and recreational activities on these wetland communities
Issue: important lakes - mesotrophic, eutrophic and marl lakes - and rivers
Actions:
- protect water quality of lakes and rivers through nutrient management and by reducing suspended sediments
- promote and encourage existing good farming practices so that streams are not polluted by run-off from agricultural land or seepage from silage pits - encourage actions such as the Erne Nutrient Management Scheme
- monitor streams and the lough in relation to expansion of rural/urban housing and recreational developments and associated septic tanks/sewage treatment plants
- monitor streams for pH and sediment loads/deposition from Forestry and any extractive activities
- promote community action to protect the lough and its associated wetland habitats, and the associated flora and fauna; e.g. encourage joint activities and policies between Wildfowlers and other conservation interests, between tourist/development interests and conservation interests etc
