Bricklieve Mountains

 

ABSTRACT

The small and well-defined uplands of the Bricklieve Mountains and Kesh Corann have geological, geomorphological, botanical, zoological and archaeological features of considerable interest and heritage value.  They are designated as both a Natural Heritage Area and as a Special Area of Conservation because of their wildlife value, but such listings mean little to most people unless information about what they contain is made more widely available.  This article briefly describes aspects of the geology, botany and zoology that can be seen by a visitor to the Bricklieves and makes reference to publications where more detailed information may be obtained.  An appendix lists 400 species of organisms authentically recorded from this area.


INTRODUCTION

The Bricklieves are a very distinctive group of hills lying close to the southern boundary of County Sligo.  They are often referred to as the Bricklieve 'Mountains' although in fact they only cover an area of about 25 square kilometres and include just two major hills, namely Carrowkeel (321m) and Kesh Corann [alias Kesh and Keishcorran] (359m).  The nearest town is Ballymote lying to the north-west, but access is most commonly gained from the north-east by leaving the main Dublin-Sligo road at the village of Castlebaldwin from where the route to the megalithic cemetery is clearly signposted and this brings one right to the heart of the Carrowkeel area.

This is an extraordinarily interesting place from several points of view.  The scenery in this small area is very special, offering many views and prospects with a landscape of limestone cliffs and rocky outcrops, steep grassy or lightly wooded scree slopes, flat heathery hill tops and some rock pavements.  The views from the summits are also very beautiful giving panoramas across Lough Arrow and distant vistas of the Ox Mountains and of Ben Bulben in the Dartry range.  It is not surprising that this area is included in the 'Inventory of Outstanding Landscapes' (An Foras Forbartha 1977) and is identified in the County Development Plan as a "Sensitive Rural Landscape" with "Visually Vulnerable" areas (Sligo County Council 1999).  The scientific value of this area has also been recognised in various reports as it was originally listed as an Area of Scientific Interest (ASI) for botanical and ecological reasons (Watts 1969; An Foras Forbartha 1972; 1978; 1981) and has more recently been designated as a Natural Heritage Area (NHA) under the Wildlife (Ammendmant) Act 2000 and most importantly as a Special Area of Conservation (SAC) under the EU Habitats Directive (92/43/EEC).  The archaeological importance of the Bricklieves is generally better known than the natural history, with the megalithic cemetery (Macalister et al. 1912; Bergh 1995, 46-54) and the Caves of Kesh being sites of a national importance (Scharff et al. 1903; An Foras Forbartha 1974; Archaeological Survey of Ireland 1990).


GEOLOGY AND GEOMORPHOLOGY

These hills are composed of a hard limestone rock, with a 335m thick sequence of sediments which were deposited during the Lower Carboniferous (Viséan), a little more than 300 million years ago (Dixon 1972).  They were laid down in a shallow marine basin that lay between two parallel island ridges running from south-west to north-east, now known to us as the Curlew Mountains and the Ox Mountains.  This basin was a small part of a much larger tropical sea with extensive coral reefs.  Rocks of the same age and origin were deposited in a similar marine basin to the north of the Ox Mountains and include Knocknarea and Ben Bulben which form the Dartry Mountains of Sligo and Leitrim and then continue eastwards into the Marble Arch area of Fermanagh.  The limestone rock we now see is rich in fossil corals, the shells of brachiopods and the stems of crinoids, which occasionally form reefs; and it also contains chert, which is a hard mineral similar to flint.

It is surprising to find that the beds of this sedimentary rock still form a nearly horizontal plateau in the Bricklieves even though they have been subjected to a long geological history.  However a great deal of chemical weathering did occur during the period between 100 and 60 million years ago resulting in the opening up of rifts, solution depressions, sinkholes and even small caves, creating a karst topography.  The chemical weathering process ceased but was replaced by physical weathering processes during the last two million years when the ice ages left their mark.  Towards the end of the last ice advance, ice sheets and glaciers, spreading from the Irish Midlands, further eroded the rock and enhanced the south-east to north-west trend of the rifts, giving Carrowkeel its very distinctive series of cliffed ridges and valleys that make the landscape so very attractive.  Looking eastwards from the plateau of Carrowkeel, one can see the same trend in the landscape continued right across Lough Arrow, where the lake's islands are glacial deposits called drumlins, and on to the hills of Highwood on the eastern side of the lake which are a miniature manifestation of the Bricklieves scenery.  The higher areas were thus stripped of rocks and laid bare, and are consequently poor for agriculture, whilst the low-lying areas received deposits of glacial till, and have a soil suitable for intensively managed grassland.  The karst topography of the Bricklieves is thus the combined result of deep chemical weathering processes opening up rifts and caves below the ground, and physical glacio-karstic processes leaving a limestone pavement on the flat summits after the surface had been stripped by glaciers.

The weathering processes continue today but at a slower rate as water sinks through the surface rock to flow underground leaving dry valleys and sink holes on the surface.  The rate of weathering on Kesh Corann has been estimated at 30mm per thousand years (Corbel 1957 quoted in Williams 1970).  Karst limestone landscapes are generally very beautiful and hold a lot of interest for geologists and cavers.  This means that a good deal tends to be written about karst limestone districts, and the great Sligo-Fermanagh caving area, as described by Chapman (1993), includes the Bricklieves.  Unfortunately, the Bricklieves have been somewhat neglected in this publication because they do not appear to contain any active cave systems and only exhibit dry caves that date far back to the pre-glacial period of deep chemical weathering.  Cruise (1878), Coleman (1955; 1965) and Knibbs (1967) all made some reference to the most obvious old dry caves in these hills; namely the Caves of Kesh, two small caves called School Cave and Pollnagaddy situated on the east side of Kesh Corann and the large sink hole of Pollnagollum on Carrowkeel.  There is also mention that there are numerous other sink holes in the peat-covered summits.  A much more thorough investigation of this karst area was carried out by Thorn, Drew and Coxon (1990) who summarised most of the available information, identified some additional caves, and also carried out some water-tracing experiments in small active systems involving sinks and springs (Coxon & Thorn 1989).


EARLIEST INHABITANTS

As the last glaciers of the ice age retreated, from about 12,000 years ago, the shallow Caves of Kesh on the west side of Kesh Corann were occupied by wild animals.  As previously indicated, these caves have little significance from a geomorphological or speleological point of view, and indeed, throughout the 19th century they were regarded as a place for an excursion for their curiosity and scenic value (e.g. Anon 1840, 9-10; Hardman 1892).  However, all this changed from around 1895 when the great cave explorer, Edouard Martel, visited Fermanagh and Mitchelstown, Co. Cork, and stimulated a new interest in serious cave research.  The Mitchelstown Caves were excavated and revealed late ice-age animal remains and the search was then on for other suitable locations.  A list of Irish caves was compiled and in a supplement the Caves of Kesh were added with the observation that a bear skull* had been recovered from deposits in 1887 (Scharff 1895; Praeger 1896).  An expedition was mounted in 1901 with a preliminary survey by Drs. Scharff and Praeger in April, followed by serious excavation work from late May, through June and July (Anon 1901a; Anon 1901b).  The announcement that bones of the Arctic lemming had been found for the first time in Ireland was of very great interest (Ussher 1902; Anon 1903a; Anon 1903b; Ussher 1906), and eventually the full results were published in a detailed report (Scharff et al. 1903).

The excavations found signs of human habitation along with the bones of ox, goat, pig, horse and marine shells in the superficial layer which was considered to have formed long after the ice-age.  Below this was a distinctive layer without any human influence believed to date from late-glacial or immediately post-glacial times and containing many bones of bears, and also some Arctic lemming remains as well as red deer, wolf, hare and pig bones.  Lists of other animals including snails, fish (trout), frog and many birds are also included in the report, but again, most of these remains were from the more recent surface layers.  However, the bones of little auk, common scoter and smew, which are uncommon or rare in Sligo today, came from older deeper layers associated with lemming bones, and probably represent a late glacial bird fauna.

In the report of the 1901 excavations it was not possible to put dates on the finds, apart from to say that the animals must have lived in Ireland since the ice-age and in some cases were now long extinct.  A further dig was carried out in 1929 which did little to advance the knowledge of the first exploration (see Gwynn, Riley & Stelfox 1940; Coleman 1947), but in more recent times new information has become available about the ages of some of the bones due to the development of the "Accelerator Mass Spectrometry Carbon-14 "(AMS C14) dating method.  Four samples of bone from the 1901 dig gave results (Woodman & Monaghan 1993) that confirm a late glacial date for the lower layers :-

Brown bear11,920 85 BP

Red deer11,790 120 BP

Wolf11,150 90 BP


and a relatively recent origin for the surface layers :-

Horse1,580 55 BP


These caves have thus been important in providing a rare glimpse into the late glacial fauna of Ireland (Stuart & Wijngaarden-Bakker 1985) and have shown that since 12,000 years ago, mammals (including brown bears, wolves, arctic lemmings and reindeer) that were once native in the Bricklieves, are now completely extinct in Ireland.

Since the ice ages different peoples have come and gone, they have hunted, farmed and altered their environment in different ways.  Once again the Bricklieves provide a most important record of some of the earlier inhabitants because the passage tombs and hut circles which are found spread widely over the dissected plateau, are a superbly preserved record of stone age and bronze age activity of this area dating from approximately 6,000-3,500 years ago.  There is much yet to be learnt from these remains but a start was made upon their exploration in 1911 (Macalister, Armstrong & Praeger 1912), although modern archaeologists are horrified at some of the methods adopted during that dig!  The history of the people who lived and worked in the Bricklieves is a story for the archaeologists and historians to tell, but their influence can not be ignored by naturalists because they have largely determined land use, and thus what is left for nature to adapt and shape within the constraints of farming practices.


FLORA AND FAUNA

Previous studies

The flora and fauna of the Bricklieves that we see today is yet another treasure of this important area.  Over the years these hills were visited by naturalists such as Foot (1871), Colgan (1902) and the famous R.Ll. Praeger who made botanical records in 1896, and was involved in cave and archaeological excavations in 1901 and 1911.  The naturalist Robert Welch took photographs of the flora at Kesh Corann in 1901 (Hackney et al. 1983).  In the late 1940s the botanist D.A. Webb made a special study of Carrowkeel (Webb 1945; 1947a; 1951; 1952) and Roger Goodwillie visited and prepared a short report on the area in the early 1970s (An Foras Forbartha 1972 which was very slightly modified in 1978).  Webb (1947a) enumerated about 240 species of ferns and flowers on Carrowkeel and commented that;

"Such a number of species for an area some 890 hectares is by Irish standards very high, if it is remembered that most of the area is over 150 meters above sea level, that it contains virtually no streams and rivers and only one small lake, and that the survey was restricted so as to exclude artificial habitats such as ploughed fields, roads and walls".

Most recently, I led a Botanical Society outing to Carrowkeel in 2001 and the flora greatly impressed the participants (Cotton 2002).  A database of all plants and animals authentically recorded from this range of hills is held by the author, and a list of 400 species derived from this database is presented in an appendix.

It was in recognition of their botanical richness as described by Webb, that the Bricklieves were designated as an Area of Scientific Interest (ASI) of National Importance in 1972; a designation that has since been superseded by them being declared a Natural Heritage Area (NHA) for their ecological interest and added to the list of Special Areas of Conservation (SAC) under the Habitats Directive of the European Union (Heritage Service 1997).


The current situation

It is a sad fact that in recent times the rate of change in the environment has greatly accelerated, usually to the detriment of wildlife.  Consequently places formerly recognised as being ecologically interesting have been partly or wholly destroyed without the knowledge of wildlife experts.  Against this background, new survey work has been undertaken in the Bricklieves in recent years (e.g. Goodwillie et al., 1992, Cotton 2002), and the following account is an integration of new and old observations.

It is good to report that most species formerly recorded from the area are still present at the beginning of the 21st century, and that recent field work has discovered the presence of some uncommon and rare species not previously noted.  It has also been apparent that descriptions made over 50 years ago in the detailed paper of Webb (1947a) are still valid, which is a very welcome observation.  It can be concluded that the diversity of habitats and species we see today in the Bricklieves are easily good enough to rate the area as being of international ecological interest.


Some general comments

Almost all natural history study in the Bricklieves has been concerned with the recording of plant species and their distributions.  Some new information is included in the following account concerning snails, moths, butterflies, birds and a few other invertebrate groups, but this is very selective and really does not do justice to the animal kingdom.  It should be pointed out that this situation is typical of the national position for our knowledge of animal groups.

An understanding of the major environmental influences on the flora of the Bricklieves must begin with the limestone, which has so little glacial drift that it frequently outcrops, and is rarely far below the ground surface.  Plants that like lime-rich soils are termed calcicole, and one would expect that many such species should be present in a limestone district.  However, whilst there are some calcicole species growing here, the resistant nature of this old limestone to weathering, and the strong influence of rainfall in leaching calcium down and away from the plant roots, has often resulted in lime-hating (calcifuge) plants living in a thin acid soil just a few centimetres above pure limestone rock.

The high rainfall, large number of rain days, high humidity and the mild nature of the climate have also come together to have a major influence on the flora.  Many species that might otherwise seek the damp protective shelter of woodland are found growing out in the open.  The ferns are particularly diverse and twenty-one species have been recorded from this area (see Appendix).  Wind is also a major factor in such a high and exposed place in the west of Ireland.  Trees are particularly affected, to the extent that vigorous tree growth can be restricted to sheltered eastern slopes and they may find it impossible to take hold on the plateau areas in situations where wind and light grazing by stock conspire to eliminate them.

Finally the activities of man, in farming the area for much of the last six thousand years, has been one of the most important factors in influencing vegetation.  The burning of heather and scrub, and the grazing of cattle must have been practised for hundreds, if not thousands of years (Bergh 1995; GÖransson, this volume) and it may be that the Bricklieves have changed very little in that long time span.

The flora and fauna of these hills will now be described, but in order to simplify the environment, it is considered best to divide it into descriptive units.  Several major habitats can be readily identified in this beautiful area, which are now listed with notes on some of their principal and special species, where they occur and their conservation value.


Woodland and scrub

If the influence of man had never been felt in this region it is believed that the natural 'climax' habitat would be deciduous woodland with a more bushy or scrubby habitat on the exposed hill tops.  Today the woodland and scrub is confined to places where grazing by large herbivores has been lessened by difficult cliffy terrain, or prevented by fences.  The result is that woodland is mainly localised to narrow strips along the bases of some of the larger cliffs, particularly along the east-facing cliffs that offer shelter from westerly winds which are also a major factor in restricting the growth of trees.  The woodland is principally composed of hazel scrub with ash, rusty-willow, hawthorn, blackthorn, rowan, birch and holly as lesser members of the tree community.  The ground flora includes wood rush, herb-Robert, wood sorrel, primrose, lesser celandine and many other shade-tolerant species.  More interesting and much rarer members of the woodland flora include whitebeam, guelder rose, spindle, midland hawthorn (the only known place for it in Sligo), and goldilocks buttercup.  Little has been done to study the fauna of these wooded areas but uncommon butterflies like the silver-washed fritillary and Real's wood white are here, with long-eared owl hunting wood mice and spotted flycatcher flying out from sunny perches along woodland edges.

The woodland here is very similar to that in hills above the northern shore of Lough Gill and in the Highwood area where hazel scrub has developed on a thin limestone soil after the exclusion of cattle and sheep.  Webb (1947a) found the woodland flora of Carrowkeel to be more similar to acid oak woodlands described for Britain than that which might be expected of a limestone district and he concluded that the high rainfall of the area was to some extent over-riding the influence of the rock-type.


Grassland

This is almost certainly a man-made habitat of considerable antiquity, that came into being after the original tree and scrub cover was removed and domestic grazing animals were allowed to browse and thus keep the scrub from reinvading.  As in The Burren of County Clare, it is likely that after clearance much of the soil would have washed down through cracks in the limestone and the remaining thin soil then supports a diversity of herbs, including some exclusively lime-loving (calcicole) species.  In the Bricklieves the herb-rich limestone grassland is mainly found on the steep scree slopes leading up to the plateau but some of the flat tops have a limestone pavement habitat akin to that of The Burren.  Grassland species such as bird's-foot trefoil, quaking grass, thyme, eyebright, common spotted orchid, lady's mantle, harebell and bulbous buttercup are often quite common, but there are also less common species like frog orchid, common twayblade and mountain cudweed.

A feature that greatly interests botanists about some Irish grasslands and hedgerows is the fact that some herbs, only found in woodland on the continent, are out in the open in places like the Bricklieves.  Primrose, pignut and bluebell are examples of such species, and the explanation for this curious situation lies in the high and frequent rainfall of such regions creating humid conditions, that are only associated with shady woodland elsewhere.  Butterflies such as the meadow brown, common blue and small heath are associated with the grassland areas, as is the 'beautiful yellow underwing' moth and a scarce woodlouse that has no common name but is known to scientists as Haplophthalmus mengei.

Another interesting fact about the herb-rich grasslands in the Bricklieves and certain other parts of Sligo and Leitrim, is the way in which the limestone grasslands intergrade into moorlands via an intermediate habitat that is sometimes called limestone heath.  In most places this intermediate habitat is more common than the limestone grassland and it includes wild flowers such as lady's bedstraw, tormentil, common milkwort, common lousewort, heath spotted orchid and even the rare small white orchid is found at two localities (Cotton, Cawley & Roden 1994; Cotton 2002).  This is a red data book species (Curtis & McGough 1988) and is listed in the Flora Protection Order of 1987.  The transition from limestone grassland to heath is often quite gradual so that as one ascends a slope, patches of limestone heath are found growing where limestone outcrops near the surface or where there are limestone boulders, and further up the limestone heath merges in to acid heath with heathers, bilberry and hard fern, at first in patches, before it takes over and blankets the ground.  In these patchwork situations it is really strange to see lime-loving and lime-hating plants growing side-by-side.

The survival of these herb-rich grasslands is largely due to the unsuitable nature of the terrain for the mechanical application of fertilisers or the possibility of getting in and ploughing and re-seeding the areas.  These operations are made difficult due to the many rocky outcrops and the steepness of many slopes, some of which are founded on old scree or lateral moraine deposits.


Moorland and bog

The high rainfall of this region coupled with a mild climate and a reduction in grazing pressure are the ingredients that allow moorland and bog habitats to take over from herb-rich grassland.  These are now the dominant habitats of most of the flat ground on top of the plateau and some of the flat valley areas found between the major ridges can often be quite wet and develop from rushy pastures into blanket bog.

The flora of these places is not very diverse and is quite typical of what one can expect over large parts of western Ireland.  In the drier places ling (common heather) dominates with some bell heather, bracken and bilberry being obvious.  A closer look will reveal smaller herbs such as tormentil, heath milkwort, heath bedstraw and occasionally there is cow-wheat and the lesser twayblade orchid.  Wet pastures tend to have clumps of soft rush, and as the peaty soil begins to accumulate then sedges, purple moor-grass and cottongrasses begin to take over.  Very wet places may have round-leaved sundew and bog asphodel in their flora.

Birds of these boggy places include the snipe in the very wet spots, but meadow pipit is the most common species and cuckoo is an occasional visitor, being a parasite on the meadow pipit.  The common heath moth and Northern eggar moth are also typical of these areas; the latter generally being spotted whizzing across the bog from a long distance!


Small lakes and marshes

These habitats are very restricted due to the porous nature of the limestone rock which means that most water flows underground.  The main area for wetlands lies between the hills of Kesh Corann and Carrowkeel where running from north to south, Lough Labe (at 144m) feeds into Lough Gowra (at 112m) and then into a turlough-like area at Greenan (at 105m).  A little lower down, and in the same alignment, there is Templevanny Lough (at 84m) which has no obvious inflowing stream and must be primarily fed from ground water flowing south from Greenan.

In karst areas such as this, springs tend to be very lime rich even though the high rainfall can result in the formation of acid bog on the ground surface.  Lough Labe is surrounded by blanket bog at its northern end and poor pasture at its southern end so at first sight it might appear to be an acid lake.  However this is far from the truth because Webb (1947b) analysed about 250 samples of surface water from around Ireland and astonishingly found that the most alkaline reading he obtained was pH8.75 and this came from Lough Labe which is therefore spring fed.  He also commented that the effluent stream from this lake vanishes after about a mile (1600m) in a swamp (Greenan) in which constant precipitation of calcium carbonate is taking place.  A biological consequence of this high alkalinity is a thriving population of white-clawed crayfish in Lough Labe which is one of the few species of invertebrate protected under national legislation.  The otter which feeds upon crayfish is also present in this lake and this is a red data book species (Whilde 1993) which is likewise protected by law.

The Inland Fisheries Trust surveyed Lough Labe in the 1950s and found it to be over 20m deep in one place.  Because they found it had poor fish stocks and was in a catchment with no surface outflow they put in the North American rainbow trout which fished well for about 20 years but although they are reported to have spawned (Whelan 1989) fish populations have once again diminished and the Regional Fisheries Board were considering whether to re-stock the lake.  Unfortunately, the steep sides to Lough Labe mean that there is no significant marsh flora and the deep water and lack of vegetation cover result in only occasional wildfowl being seen on the surface.

Lough Gowra is being used as a storage reservoir for a local water scheme and consequently has fluctuating water levels with quite low levels in the summer that expose large areas of marsh and mud around the shore.  In the winter this small lake is frequented by about fifty duck including mallard, wigeon, teal and tufted duck.  The flora around this lake has a poor diversity and appeared to lack interest until in June 2000 I discovered thousands of plants of fen violet in a band at a particular level all around the lake shore.  It would seem that the fluctuating water levels have created a very special habitat for this species and its associated community of plants.  The fen violet is a red data book species (Curtis & McGough 1988) with a very local and threatened Irish distribution and this is the first record of it in County Sligo.  In Great Britain it is in danger of becoming extinct and stringent conservation measures are being taken at its three known sites (Anon 2001).  This is yet another special species that adds to the interest and wildlife importance of the Bricklieves and it makes one wonder what other species might await discovery here.

Greenan is quite a different story because the fenny marsh is floristically very diverse with a patchwork of habitats reflecting the different degrees of flooding and inundation.  For example there is a distinctive area of large tussocks typically formed by sedges that are subjected to regular flooding.  Here the common sedge and bottle sedge are dominant with some greater tussock sedge, brown sedge, lesser-pond sedge, marsh willowherb and common marsh-bedstraw.  An island of drier habitat is sandwiched between this flood-sedge and an open water area which has a small number of willows beneath which there is tufted sedge, but also a clump of the greater spearwort and slender tufted-sedge which are very scarce in Sligo.  The more permanent water has a flora that includes mare's-tail, branched bur-reed, thread-leaved water-crowfoot, amphibious bistort, water forget-me-not, water mint and the uncommon lesser marshwort.   This site was considered to be worthy of 'Area of Scientific Interest' status by Goodwillie et al. (1992) and some records from it were published by Douglas et al. (1993).  The wintering wildfowl at Greenan are also important with over 150 duck often being present with occasional whooper swans which is a priority species listed in the EU Birds Directive (79/409/EEC).

Templevanny Lake is also of some interest as there is a small population of marsh fritillary butterflies here (a species protected by the EU Habitats Directive), smooth newt is nearby (a red data book species), the marsh flora is diverse and interesting, and small numbers of duck overwinter here.

There used to be a small lake in the heart of Carrowkeel which is still shown as Lough Availe on the Ordnance Survey map.  Webb (1947a) described the flora of this lake in some detail from observations made in 1942-1945, but in 1946 G.F. Mitchell observed that the lake had been drained.  Recent visits show that there is no longer a lake here, in that there is no open water, but upon traversing the area it is obvious that there is a thick layer of vegetation floating on a closed lake, a habitat that is often referred to as a 'scraw bog'.  The vegetation here is still quite interesting with plants typical of both acid and alkaline conditions occurring in different parts of the quaking marsh.  The most interesting species are the Royal fern and broad-leaved cottongrass.  The protected marsh fritillary butterfly is present here in association with its food plant, devil's-bit scabious.


Rock outcrops

Limestone cliffs abound in this region and offer ledges as sanctuary from grazing animals such as cattle and sheep.  The walls of the sink holes, most notably of Pollnagollum on Carrowkeel, also offer a safe haven for a similar, but more luxuriant, flora.  The vegetation of these places is an extension of the limestone grassland community with many species being calcicole.

There are many interesting and quite rare species to be found in these habitats and the list would whet any botanist's appetite; hairy rock-cress, hoary whitlowgrass, mossy saxifrage, black spleenwort, brittle bladder fern, early purple orchid, Welsh poppy, wall rue, maidenhair spleenwort, hard shield fern, water avens, fairy flax and stone bramble.  An uncommon fern not seen in recent years is the green spleenwort (noted on Kesh Corann by Foot 1871).

A related habitat is offered by the megalithic cairns, and it is particularly interesting to see the similar-looking species of common whitlowgrass, hairy rock-cress and hoary whitlowgrass growing together, especially as the last two are not at all common with hoary whitlowgrass being a red data book species (Curtis & McGough 1988).  Biting stonecrop and shining crane's-bill are also typical of the stone cairns but are uncommon elsewhere.

The fauna of the cliffs also has some specialities of the creepy-crawly variety, although they have never been properly surveyed, namely Megabunus diadema - a harvest-spider, Armadillidium pulchellum - a woodlouse, and Acicula fusca which is a tiny snail.  Birds using the cliffs and rock cervices include wheatear, peregrine and raven.  Unfortunately the peregrines are considered quarry by some 'sportsmen' and reports indicate that on at least one occasion a bird has been shot to be made into a trophy for a local public bar.


LOOKING TO THE FUTURE

The Bricklieves are a small but important area of great heritage value.  They offer a fascinating landscape of cliffs, bogs, herb-rich grasslands and limestone pavement through which a walker may find solitude and great natural beauty.  Many surprises and delights await discovery with geological features, archaeological monuments and a diversity of wild flowers and animals that together give a unique blend of interest for the natural history student and the rapidly increasing numbers of environmentally aware local people and tourists.

The area has been modified by thousands of years of human history and yet remains largely unspoilt.  However, the next hundred years might prove to be the most traumatic in its long history because rapid changes in land use, driven by environmentally blind economic forces, are happening all over Ireland.  Sheep grazing has already proven to be a problem on Kesh Corran with changes in the floral composition of the grasslands over vast areas being obvious on close inspection.  No longer are the herb-rich pastures clothing the hillsides or the heathery tops so prevalent as they were just 10 years earlier.  Another threat could be from grant-aided forestry, that can be planted over large tracts of land in a few weeks, and although the effects are not immediately apparent, the existing flora is doomed from that moment onwards.

Introduced species of flora and fauna can also cause severe problems.  The mountains of Sligo have been invaded by the New Zealand willowherb over the last twenty years and recently this species has been noted in the Bricklieves.  Who knows how it will compete with native plants, especially on the limestone cliffs and ledges?  Similarly, small leaved Cotoneaster is present in an area of limestone pavement in the Bricklieves and may well become rampant as it has invaded other areas of limestone heath in Sligo.

Uncontrolled tourism may also be a threat to such a sensitive landscape.  Large numbers of tourists may seem like a dream scenario to local enterprise, but without careful forward planning, the very attraction of the wild places can be destroyed by a development such as a road leading too far into the original pristine resource.  What are today beautiful hill-top views may be permanently scarred by eroded footpaths, tracks and litter, just as has happened in many other places in Europe where the clock can not be turned back.  As an area opens up pressure comes on for the development of holiday homes, at first around the edge of the area and gradually further and further in to the area as roads are improved.  The Bricklieves may be saved this fate due to the lack of potable water, but every house poses a threat in such an area from the disposal of septic tank waste going straight in to the groundwater and from its impact on the scenery.  In 2001 a local water scheme at Carricknahorna East was upgraded which included 'improving' a mountain track with heavy earth-moving equipment, building a concrete sump over a species-diverse natural spring and diverting another spring down pipes with the drainage and loss of a herb-rich fen, all within the boundaries of the SAC.  If such damage is to be avoided then environmentally aware people must be very vigilant and ecologists must be consulted to help find ways of developing such schemes without the negative environmental impact.

Let us hope the Bricklieves survive the 21st century through good planning and environmental management.  Such a plan has been proposed as a part of a Masters thesis (Brakspear 1996) which combines the archaeological and ecological interest in the Bricklieves using principles of sustainable-tourism, so hopefully the recommendations will be used and the report will not just gather dust.  A new field studies centre is built and will be functioning very soon at Ballinafad on the south-east margin of this area which could bring 'eco-tourism' to this area in a big way.  Let us hope that these hills are enjoyed by an increased number of people because it is going to be through love and understanding that their eventual security will be won for all time!



FURTHER READING

The following publications, used in the preparation of this article, can be obtained by those wishing to delve more deeply into the science of the Bricklieves :-


An Foras Forbartha 1972:  Heritage Inventory Reports for Co. Sligo.  Areas of Scientific Interest in Co. Sligo. (Preliminary report).  An Foras Forbartha, Dublin.  (Unpublished report).

An Foras Forbartha 1974:  Heritage Inventory Reports for Co. Sligo.  Monuments of Archaeological Interest.  An Foras Forbartha, Dublin.  (Unpublished report).

An Foras Forbartha 1977:  Inventory of Outstanding Landscapes.  An Foras Forbartha, Dublin.

An Foras Forbartha 1978:  Heritage Inventory Reports for Co. Sligo.  Areas of Scientific Interest in Co. Sligo. (Revised and expanded report). An Foras Forbartha, Dublin.  (Unpublished report).

An Foras Forbartha 1981:  Areas of Scientific Interest in Ireland.  An Foras Forbartha, Dublin.

Anon 1840:  The caves of Kish-Corran.  The Irish Penny Journal, 1(2), 9-10.

Anon 1901a:  News gleanings.  The cave committee's work.  Ir. Nat., 10, 141-142.

Anon 1901b:  Notes.  Geology.  Exploration of the Keish caves.  Ir. Nat., 10, 256.

Anon 1903a:  Proceedings of Irish Societies.  Belfast Naturalists' Field Club.  Ir. Nat., 12, 19-21.

Anon 1903b:  Proceedings of Irish Societies.  Belfast Natural History and Philosophical Society.  Ir. Nat., 12, 51.

Anon 2001:  Species Recovery Programme.  Fen violet Viola persicifolia.  Flora English Nature Winter 2001:9.

Archaeological Survey of Ireland 1990:  County Sligo Sites and Monuments Record.  The Office of Public Works, Dublin.

Bergh, S. 1995:  Landscape of the Monuments.  A study of the Passage Tombs in the Cuil Irra region, Co. Sligo, Ireland.  Arkeologiska undersokningar. Skrifter nr 6. Riksantikvarieambetet, Stockholm.

Brakspear, R. 1996:  Archaeology and Nature Conservation: Implications for the management of ancient monuments and historic landscapes in Ireland.  M.Sc. thesis, University College, North Wales.

Caldwell, W.G.E. & H.A.K. Charlesworth 1962:  Visean coral reefs in the Bricklieve Mountains of Ireland.  Proc. Geol. Assoc., 73, 359-382.

Chapman, P. 1993:  Caves and Cave Life.  The New Naturalist, HarperCollins, London.

Coleman, J.C. 1947:  Irish cave excavations.  J. Roy. Soc. Antiq. Ireland, 77, 63-80.

Coleman, J.C. 1955:  Notes on the cave region of North West Ireland.  Cave Research Group Newsletter, No. 52, 25-28.

Coleman, J.C. 1965:  The Caves of Ireland.  Anvil Books, Tralee.

Colgan, N. 1902:  Notes.  Botany.  Some new county records.  Ir. Nat., 11, 184.

Cotton, D.C.F., M. Cawley & C. Roden 1994:  Botanical note.  On the occurrence of Pseudorchis albida in Sligo (H28), Leitrim (H29) and Galway (H15, H16 and H17).  Ir. Nat. J., 24(11), 468-471.

Cotton, D.C.F. 2002:  Reports of field meetings - 2001.  O'Rourke's Table, Co. Leitrim (v.c. H29). & Cullentra Wood, Bricklieve Mountains & Unshin River, Co. Sligo (v.c. H28) 16th & 17th June.  BSBI News No.89:60-61.

Coxon, C. & R.H. Thorn 1989:  Temporal variability of water quality and the implications for monitoring programmes in Irish limestone aquifers.  Pages 111-120 in: Groundwater Management : Quantity and Quality.  Proceedings of the Benidorm Symposium, IAHS Publication no. 188, 1989.

Cruise, R.J. 1878:  Explanatory memoir to accompany sheets 66 and 67 of the maps of the Geological Survey of Ireland illustrating part of the Counties of Sligo, Leitrim, Roscommon and Mayo.  Memoirs of the Geological Survey, Dublin.

Curtis, T.G.F. & H.N. McGough (1988)  The Irish Red Data Book.  1. Vascular Plants.  Stationery Office, Dublin.

Dixon, O.A. 1972:  Lower Carboniferous rocks between the Curlew and Ox Mountains, Northwestern Ireland.  J. Geol. Soc., 128, 71-101.  (12 figures).

Douglas, C., R. Goodwillie & E. Mooney 1993:  Botanical notes.  Notes on the flora of the Owenmore catchment Cos. Sligo (H28) and east Mayo (H26).  Ir. Nat. J., 24(5), 218-220.

Foot, F.J. 1871:  On the occurrence of Hymenophyllum Wilsoni in the neighbourhood of Boyle; with notice of new stations for some of our rarer plants in the surrounding district.  Proc. Nat. Hist. Soc. Dublin (for the sessions 1865-1869), 5, 16-17 [discussion of paper 17-20].

Goodwillie, R., Buckley, P. & C. Douglas 1992:  Owenmore River.  Proposed Arterial Drainage Environmental Impact Assessment.  Botanical and Ornithological Surveys.  A report for National Parks and Wildlife Service, Office of Public Works.  (Unpublished report).

Goransson, H. 1996:  Pollen analytical investigations in the Sligo area.  In: Timoney, M.A. (ed.) A Celebration of Sligo.  Sligo Field Club, Sligo.

Gwynn, A.M., F.T. Riley & A.W. Stelfox 1940:  Report on a further exploration (1929) of the caves of Keshcorran, Co. Sligo.  Proc. R. Ir. Acad., 46B, 81-95.

Hackney, P.; K.W. James & H.G.C. Ross 1983:  A list of the photographs in the R.J. Welch Collection in the Ulster Museum.  Volume 2 Botany, Geology and Zoology.  Ulster Museum, Belfast.

Hardman, E.J. 1892:  The limestone caves of Sligo.    Volume 3, Appendix A: 375-378 in:  Wood-Martin, W.G.  History of Sligo.  Hodges, Figgis & Co., Dublin.

Heritage Service 1997:  Co. Sligo.  Proposed Natural Heritage Areas (pNHA) and proposed Candidate Special Areas of Conservation (pCSAC).  Map 19.  National Parks & Wildlife, Heritage Service, Dublin.

Knibbs, A.J. 1967:  Ireland - 1962.  J. Mendip Caving Group, Volume 4.

Macalister, R.A.S., E.C.R. Armstrong & R.L. Praeger 1912:  Report on the exploration of bronze age carns on Carrowkeel Mountain, Co. Sligo.  Proc. R. Ir. Acad., 29C, 311-347 with 16 plates.

Praeger, R.Ll. 1934:  The Botanist in Ireland.  Section 382.  Hodges, Figgis & Co., Dublin.

Scharff, R.F. 1895:  Cave at Ballymote, Co. Sligo.  Ir. Nat., 4, 94.

Scharff, R.F., G. Coffey, G.A.J. Cole, R.A. Ussher & R.L. Praeger  1903:  The exploration of the caves of Kesh, County Sligo.  Trans. R. Ir. Acad., 32(B), 171-244.  Plates 9-11.

Sligo County Council (1999)  Development Plan for the County of Sligo 1999-2004.  Sligo County Council, Sligo.

Stuart, A.J. & L.H. van Wijngaarden-Bakker 1985:  Quaternary Vertebrates.  Chapter 10: 221-249 in: Edwards, K.J. & P. Warren (eds.)  The Quaternary History of Ireland.  Academic Press, London.

Thorn, R., D. Drew & C.Coxon 1990:  The hydrology and caves of the Geevagh and Bricklieve karsts, Co. Sligo.  Ir. Geog., 23(2), 120-135.

Ussher, R.J. 1902:  The British Association in Belfast.  Report of the committee appointed to explore Irish caves.  Ir. Nat., 11, 272-273.

Ussher, R.J. 1906:  Discoveries in Irish and other bone caves.  J. Waterford and south east Ireland Arch. Soc., 9, 1-11 with illustration of Keish cave Co. Sligo.

Watts, W.A. 1969:  1. Map of Areas of Scientific Value in Ireland.  Appendix 3 in : Anon (1969) The Protection of the National Heritage.  An Foras Forbartha, Dublin.

Webb, D.A. 1945:  Botanical notes.  Some new county records.  Ir. Nat. J., 8, 313-314.

Webb, D.A. 1947a:  The vegetation of Carrowkeel, a limestone hill in NW Ireland.  J. Ecol., 35, 105-129.

Webb, D.A. 1947b: Notes on the acidity, chloride content, and other chemical features of some Irish fresh waters.  Scientific Proceedings of the Royal Dublin Society 24(24):215-228.

Webb, D.A. 1951:  The vegetation of Carrowkeel reproduced notes.  Botany School, Trinity College Dublin 5(2), 23-49 with figures.

Webb,D.A. 1952:  Botanical notes.  Alchemilla vulgaris agg. in Ireland: a preliminary report.  Irish naturalists' Journal 10:298-300.

Whelan, K. 1989:  The Angler in Ireland.  Game, Coarse and Sea.  Country House, Dublin.

Whilde, A. 1993:  Threatened Mammals, Birds, Amphibians and Fish in Ireland.  Irish Red Data Book 2: Vertebrates.  HMSO, Belfast.

Williams, P.W. 1970:  Limestone morphology in Ireland.  Chapter 7: 105-124 in : Stephens, N & R.E. Glasscock (eds.)  Irish Geographical Studies.  Department of Geography, Queen's University of Belfast.

Woodman, P.C. & N. Monaghan 1993:  From mice to mammoths.  Dating Ireland's earliest faunas.  Archaeology Ireland, 7(3), 31-33.


AppendixSpecies of organisms recorded from the Bricklieves that are on the database of the author.

*species mentioned in text

+species known from archaeological deposits