The Mourne Gullion Strangford Geopark features a diversity of landscape taking in mountain, craggy uplands, rolling green hills, coastal plains and hard and soft seashore. The Geopark includes three Areas of Outstanding Natural Beauty, designated for the distinctiveness and quality of the landscape, and in turn these landforms support a rich array of wildlife and plants recognised in a range of international, European and national conservation designations.
For those wondering why such a variety of natural heritage can be found in this compact region, the answer lies deep in the prehistory of the earth, beginning when this place – and indeed the entire surface of the earth – looked very, very different. It took, over millennia, the shifting of continents, volcanic activity and, particularly, the effects of the various Ice Ages to sculpt the rocks and shape the land and habitats. The story of the natural heritage of our region is a long and epic one.
Mountain
The upland areas of the Geopark are underlain by igneous rocks, exposed by erosion of the sedimentary rocks within, which they had originally cooled beneath the earth’s surface. Slieve Croob belongs to the Newry Igneous Complex, emplaced as the ancient Iapetus ocean closed over 400 million years ago, when our climate would have been like the Sahara desert. The ‘younger’ uplands of the Mournes and Ring of Gullion are underlain by granite and gabbro dating back to the opening of the North Atlantic ocean, about 56 million years ago. Our coastal location and our northern latitude, when all of the tectonic activity settled down, has subsequently much influenced our landscape and habitats.
Based on hard, slowly eroding granites the upland areas have thin, poorly draining soils. The altitude, bringing strong winds, low temperatures and high rainfall, means organic material breaks down only slowly. The result is peaty layers, low in nutrients, often water logged and highly acidic. In the harsh conditions, only specialist plants and animals survive.
Our mountains feature some blanket bog, dominated by sphagnum mosses, but more prevalent is the upland wet and dry heath with Slieve Gullion and the Mourne Mountains supporting internationally important tracts. Characterised by heathers, the habitat supports many other plants including cotton grasses, cowberry and the insectivorous sundew and butterwort. The tranquillity of the mountains make them a haven for various birds and animals including the peregrine falcon and Irish hare.
The lower, craggy uplands of Slieve Croob are characterised by outcrops of ancient granites and also exhibit poor soils, left shallow and stony as the ice scoured its way from the higher slopes. This encourages a proliferation of gorse and bracken, the former bringing a bright yellow hue to our spring time.
Countryside
Much of the region around the uplands was covered by material moved and shaped at the base of ice sheets as they advanced and retreated, depositing glacial sediment. From the plain between the mountains and the sea to the characteristic drumlins that form the classic ‘basket of eggs’ landscape of low rounded hills to the north and east of the region, these are soft, fertile landscapes.
Poorly drained hollows between the drumlins mean that small lakes and ponds are a common feature, while bigger water bodies, like Camlough Lake are a result of glacial scouring. The inter-drumlin areas also support some lowland raised bogs with specialised plants including cotton grasses, cross leaved heath and bog asphodel.
Purple rush grass and rushes are common in field corners and smaller wet pockets.
The ‘up and down’ topography contributes to a pattern of small field enclosures, which in turn helped preserve species rich hedgerows along field boundaries. These habitats are particularly important as woodland cover is low in the region. Poorer foothill slopes have seen conifer plantation and so the small patches of native broadleaf survive mainly in the river valleys, the hedgerows and ‘shelter belts’ around older farms.
The flatter coastal landscape of Lecale has some fens, areas with a permanently high water level at or just below the surface, which are important for invertebrates like the Irish damselfly and whirligig beetle. These are developed on sedimentary rocks that formed on the bottom of a long disappeared ocean. The Kilkeel plain, the area’s most recent geological feature formed from sands and gravels which came as outwash from the melting glaciers, and subsequently small rivers cut through the soils and soft sediments to form inaccessible hidden valleys that are a haven for wildlife.
Coast
The region’s long coastline combines hard rocky coves with boulder clay cliffs and mobile sediments of shingle, sands and mud – the presence of which again owes much to the movement of ice.
Moraines deposited as the ice sheets retreated, have been cut into by the sea to form soft cliffs, loved as nesting sites by sand martins, jackdaws and starlings among other burrow nesting birds. In addition, the materials set down on the sea floor have provided abundant sediments to be reworked by rising sea levels over the millennia. Sand dunes at Murlough on Dundrum Bay and Killard near Strangford Lough, are two of the largest systems in Northern Ireland. The former is home to the largest population of the marsh fritillary butterfly in Northern Ireland and the latter is one of the best sites for grassland and lowland heath invertebrates.
Also formed from the glacial deposits are sand and shingle beaches and mud flats. The rich sea larder of the flats at places like Carlingford Lough and Killough Bay are vital feeding and resting areas for internationally important populations of migratory, over-wintering and breeding wildfowl including oyster catcher, green shank and the light-bellied Brent goose.
It is important to remember that the landscape we see around us today is a chapter in time; it is somewhere in the middle of a story. We are part of a world formed of rock but not set in stone, instead constantly moving and changing around us, often so slowly we are unaware of it but also all too quickly and visibly in some cases.
Managing the impacts of the forces of change arising on the land forms, habitats and species outlined is a key task of our Geopark.
