Early history

Cloistered courtyard in Muckross Abbey

Killarney National Park is one of the very few places in Ireland that has been continuously covered by woodland since the end of the most recent glacial period,^[13] approximately 10,000 years ago. Humans have lived in the area since at least the Bronze Age, approximately 4,000 years ago. Archaeologists have found evidence that copper mining took place in the Ross Island area during this period, which suggests that the area was of considerable importance to Bronze Age people. The park has many archaeological features, including a well preserved stone circle at Lissivigeen.^[1] The woods in the park have been disturbed and cleared at different periods since the Iron Age. This has caused a gradual decline in the diversity of tree species in the park.^[13]

A 19th century map of the Lakes of Killarney, produced for early tourists

Some of the most impressive archaeological remains in the park are from the early Christian period. The most important of these features is Inisfallen Abbey, the ruins of a monastic settlement on Inisfallen Island in Lough Leane. It was founded in the 7th century CE by St. Finian the Leper and was occupied until the 14th century.^[14] The Annals of Inisfallen, a record of the early history of Ireland as it was known by the monks, was written in the monastery from the 11th to 13th centuries.^[4] It is thought that the monastery gave rise to the name Lough Leane, which means "Lake of Learning".^[14]

Muckross Abbey was founded in 1448 by Observantine Franciscans and is also still standing, despite having been damaged and reconstructed several times when its inhabitants were raided. "Friars Glen" on Mangerton Mountain is customarily said to have been one of the places the monks would flee to when the monastery was attacked. The central feature of Muckross Abbey is a central courtyard that contains a huge yew tree surrounded by a vaulted cloister.^[14] It is traditionally said that this tree is as old as Muckross Abbey itself.^[1] The abbey was the burial place of local chieftains. In the 17th and 18th centuries the Kerry poets Seafraidh O'Donoghue, Aogán Ó Rathaille, and Eoghan Rua Ó Súilleabháin were buried there.^[4]

Ross Castle

After the Norman invasion of Ireland, the land around the lakes was owned by the McCarthys and O'Donoghues.^[4] Ross Castle is a 15th-century tower house on the shore of Lough Leane. It was once the residence of the chieftain O'Donoghue Mór. The castle was extended in the 17th century. It has been restored and is open to the public.^[14] A 1580s Elizabethan military record describes the Killarney area as a meagrely inhabited wilderness of forest and mountains.^[13]

From the 18th century the land in today's park were divided between two great estates, the Herberts of Muckross and the Brownes (Earls of Kenmare). During the 17th and 18th centuries the woods were extensively utilised for local industries including charcoal production, cooperage and tanning. Pressure on the woods intensified in the later part of the 18th century.^[13] The biggest cause of oakwood destruction in Killarney in the 18th century was the production of charcoal to fire smelters used in the local iron industry. Approximately 25 tons of oak was needed to produce one ton of cast iron.^[15] In 1780 Young famously described Derrycunihy wood as "a great sweep of mountain, covered partly in wood, hanging in a very noble manner, but part cut down, much of it mangled, and the rest inhabited by coopers, boat-builders, carpenters and turners..."^[13]

Woodland exploitation again increased during the Napoleonic era in the early 19th century, probably because of the high prices that oak was commanding at this time. Replanting and management of the oak forests was promoted at this time. There was a large-scale felling of oak trees at Ross Island in 1803, Glena in around 1804 and Tomies in 1805. Tomies was then replanted with three-year-old oak and Glena was coppiced. These activities have increased the relative abundance of oak in the park in the past 200 years.^[13] As most of the oak trees in the woods today are around 200 years old, it is likely that the majority of them were planted, and the oakwoods that have never been disturbed by humans are restricted to a few isolated pockets in remote areas such as mountain valleys.^[15]

The Herbert family owned the land on the Muckross Peninsula from 1770 onwards. They became very wealthy from copper mines on this land. Henry Arthur Herbert and his wife—the water colourist Mary Balfour Herbert—finished building Muckross House in 1843. The Herbert's financial situation became precarious in the late 19th century,^[16] and the Muckross estate was purchased by Lord Ardilaun of the Guinness brewing family in 1899.

Creation of the park

In 1910, the American William Bowers Bourn bought Muckross Estate as a wedding present for his daughter Maud on her marriage to Arthur Vincent.^[17] They spent £110,000 improving the estate between 1911 and 1932, building the Sunken Garden, the Stream Garden, and a rock garden on an outcrop of limestone.^[16]

Muckross House as seen from the top of Torc Mountain

Maud Vincent died from pneumonia in 1929.^[16] In 1932, Arthur Vincent and his parents-in-law donated Muckross Estate to the Irish state in her memory. The 43.3 square kilometres (10,700 acres) estate was renamed as the Bourn Vincent Memorial Park. The Irish government created the national park by passing the Bourn Vincent Memorial Park Act in 1932.^[7] The Act required the Commissioners of Public Works to "maintain and manage the Park as a National Park for the purpose of the recreation and enjoyment of the public."^[16] The memorial park is the core of today's enlarged national park.^[7]

Initially the Irish Government was unable to provide much financial support to the park, so it operated primarily as a working farm that was open to the public.^[7] Muckross House was closed to the public until 1964.^[18]

Around 1970 there was public disquiet about threats to the Bourn Vincent Memorial Park. The Irish authorities looked at international practices in classifying and managing of national parks. It was decided to expand and re-designate the park as a national park that corresponded broadly to IUCN Category II. A decision was also made to establish other national parks in Ireland.^[8] Almost 60 square kilometres (15,000 acres) has been added to the original park, including the three lakes, Knockreer Estate, Ross Island, Innisfallen, and the townlands of Glena, Ullauns, and Poulagower.^[4] The park is now more than double the size it was in 1932.^[19] As the Irish economy became wealthier and the perception of the role of national parks changed, much more money was made available to the park.^[7]

Oak woodlands

The park is perhaps most famous for its oak woodlands,^[3] which are about 12.2 square kilometres (3,000 acres) in size.^[13] They form the largest area of native woodland remaining in Ireland and are a remnant of the woodland that once covered much of Ireland. Derrycunihy Wood is perhaps the most natural sessile oak (Quercus petraea) wood in Ireland. Most of the oak woodlands are located on the lower slopes of the Shehy and Tomy mountains, adjacent to Lough Leane. They are typically dominated by sessile oak, which favours the acidic soils of the sandstone mountains.^[15] The woods have Annex I status in the EU Habitats Directive because of their diverse and rich flora, most notably their bryophytes (mosses and liverworts).^[2]

The oak woodlands typically have an understory of holly (Ilex aquifolium). Strawberry trees (Arbutus unedo) are a notable part of these woods. There are also scattered yews.^[3] The field layer includes bilberry and woodrush.^[15] The herb layer is not rich in species.^[6]

Bryophytes, lichens and filmy ferns (Hymenophyllaceae), thrive in the humid oceanic climate. Species with restricted Atlantic distributions grow in the woods.^[2] The bryophytes in these woods are perhaps the best-developed Atlantic bryophyte community in Europe.^[3] The remote Glaism na Marbh valley has a particularly rich flora of bryophytes, some of which are scarce or absent in other parts of the woods.^[13] Mosses, ferns and liverworts frequently occur as epiphytes, attached to the trunks and branches of oak trees.^[15] Rare species growing in the woods include Cyclodictyon laetevirens, Daltonia splachnoides, Lejeunea flava, Radula carringtonii, and Sematophyllum demissum.^[6]

Bird species that reside in the oak woods include blue tit, common chaffinch, goldcrest, European robin, and wren. Mammals include badger, fox, pine marten, red deer, sika deer, and red squirrel. Insects include many species of the parasitic gall wasp and the purple hairstreak butterfly, whose caterpillar is entirely dependent upon oak trees.^[15]

The introduced common rhododendron is a large threat to certain areas of the oak woods.^[15] For example, it is widespread throughout Camillan Wood despite ongoing attempts to control it.^[2]

Yew woodlands

Reenadinna yew wood

The yew woodland in the park is known as Reenadinna Wood. It is about 0.25 square kilometres (62 acres) in size and is located on low-lying karst limestone pavement between Muckross Lake and Lough Leane on Muckross Peninsula.^[2] Yew woodland is the rarest habitat type in the park.^[22] Yew woodlands are one of the rarest types of woodland in Europe, mostly restricted to western Ireland and southern England. It has priority habitat status under Annex I of the EU Habitats Directive.^[2] Reenadinna Wood is also one of the largest woods that are dominated by common yew (Taxus baccata L.) in the UK and Ireland.^[23] It is the only significant area of yew woodland in Ireland and is one of just three pure yew woodlands in Europe.^[22] It is of considerable ecological and conservation interest, as yew is rarely a woodland dominant. The western limit of the wood lies along the geological boundary with Devonian Old Red Sandstone. The wood is bounded to the east by parkland where the limestone no longer outcrops. Muckross bog, a raised bog 0.02 square kilometres (4.9 acres) in area, is in the southern part of the wood. There are hollows between the limestone outcrops. Deep rendzina soils have developed in some of the hollows. It is estimated that the wood developed 3,000–5,000 years ago.^[23]

Yew is a native evergreen tree that grows best in the high humidity of mild oceanic climates, which makes Killarney a very suitable location.^[24] The soil in the wood is mostly thin and in many places the trees are rooted to fissures in the bare limestone.^[22] Yew has an extensive horizontal root system. In the Killarney woods, the roots spread out over the rock surface and penetrate deeply into fissures in the limestone.^[24] The wood has a low canopy of 6–14 m (20–46 ft).^[2] Yew's extreme tolerance of the dense shade its canopy creates has allowed it to outcompete other species to create the pure yew woodland present today.^[24] This dense shade prevents flowering plants from establishing themselves in these woods and prevents the herb layer from developing. Bryophytes are, however, abundant and thrive in humid and cool conditions. In some parts of the wood, there are continuous dense blankets of moss that can be up to 152 centimetres (60 in) deep.^[22] The moss species present are primarily Thamnium alopecurum with Eurhynchium striatum and Thuidium tamariscinum.^[24]

Some of the trees in Re-enadinna wood are two hundred years old.^[3] There has been little regeneration of the yew trees in the wood. Overgrazing of the woodland floor by sika deer may be part of the reason for this, but small areas of the wood that have been fenced off since 1969 have experienced very little yew regeneration. The dense canopy created by the yew trees that lets very little sunlight through to the woodland floor may also prevent the growth of yew seedlings.^[22]

Despite its poisonous properties, yew is very susceptible to browsing and bark stripping by deer, rabbits, hare, and domestic animals. It is one of the most grazing sensitive trees in the Killarney woodlands. Sika deer have killed yews by scoring the trees with their antlers.^[24]

Wet woodlands

Wet woodland (also called carr) on the low-lying swampy limestone areas within Lough Leane's floodplain is about 1.7 square kilometres (420 acres) in size.^[25] This is one of the most extensive areas of this woodland type in Ireland. The dominant canopy species here are alder (Alnus glutinosa), ash (Fraxinus excelsior), downy birch (Betula pubescens), and willow (Salix spp.).^[3] The areas that are periodically covered by water are rich in species including grasses, rushes, sedges, and flowers such as marsh bedstraw, meadow sweet, and water mint.^[15]

Red deer and sika deer heavily use the wetland woods as cover, and bare muddy "deer wallows" are a characteristic feature. Rhododendrons are the greatest threat to these woodlands. They are invading the woodlands, using raised areas such as tussocks or tree bases where the floor is too wet for seedlings to become established. Although some clearance has occurred reinvasion continues.^[25]

Bryophytes

Bryophytes (mosses and liverworts) flourish in the park, due partly to the area's mild oceanic climate. The park is internationally significant for bryophytes. Many of the bryophytes found in the park are not found anywhere else in Ireland.^[26] Mosses, ferns such as filmy ferns, and liverworts grow luxuriantly. Many of them live as epiphytes, growing on the branches and trunks of trees.^[4]

Other plant species

The Killarney fern (Trichomanes speciosum) is probably the most rare plant species in the park. It is a filmy fern that grows in the splash zone of waterfalls and other damp places. Although it was once quite common, it was picked almost to extinction when pickers collected it to be sold to tourists. The few sites where this fern remain tend to be in isolated mountainous locations where pickers never found it.^[26]

Although the strawberry tree (Arbutus unedo) is relatively common in the park, it is one of Ireland's rarest native tree species and is found in very few locations outside Killarney. In the park it is found on cliff tops and the edges of the woodlands around the lake.^[26]

Killarney whitebeam (Sorbus anglica) is a shrub or small tree that grows on rocks close to lakeshores. It is found only in Killarney. The more common Irish whitebeam (Sorbus hibernica) is also found in the park.^[26]

The greater butterwort (Pinguicula grandiflora) (also known as the Kerry violet) is a carnivorous plant found in bogs. It digests insects to supplement the poor supply of nutrients (especially nitrogen) available from the bog. Its purple flowers bloom in late May and early June.^[26]

Irish spurge (Euphorbia hyberna) is an Atlantic species that in Ireland is only found in the southwest. In the past the milky sap from its stem was used to cure warts. Fishermen used it to capture fish, utilising compounds in the sap that prevent fish gills from functioning properly and so suffocate the fish.^[26]

A number of rare species of myxomycete fungus have been recorded in the park. These are Collaria arcyrionema, Craterium muscorum, Cribraria microcarpa (the only known location in Ireland), C. rufa, C. violacea, Diderma chondrioderma, D. lucidum, D. ochraceum, Fuligo muscorum, and Licea marginata.^[6] The park has a highly diverse lichen flora.^[26]

Mammals

Most mammals native to Ireland and long established introduced species are found in the park.^[4] The bank vole was first identified in 1964 in northwest Kerry. Its range has now expanded and now includes the park.^[4] Pine marten is another notable species in the park.^[6]

Deer

A male red deer in oak woodland

The park has Ireland's only remaining wild herd of native deer (Cervus elaphus), comprising approximately 900 individuals.^[27] an increase from less than 100 individuals in 1970.^[28] They are found in upland areas of the park, mostly on Mangerton and Torc mountains. This herd has been continuously in Ireland for 4,000 years, since the return of red deer to the island, possibly aided by humans, after the last ice age,^[4] approximately 10,500 years ago.^[27] They were protected in the past by the Kenmare and Muckross estates. The herd is not completely pure because stags were introduced to the herd to improve antler quality in the 19th century.^[28]

Pregnant hinds from the lowland areas frequently go to the mountains to give birth in early June. The National Park staff tags the calves. Although red deer and sika deer are capable of interbreeding, no cases of crossbreeding have been recorded in the park. High priority is given to maintaining the genetic purity of the native red deer herd. Red deer are fully protected by law, and their hunting is not permitted.^[27]

Sika deer (Cervus nippon) were introduced to the park from Japan in 1865. Their population has increased considerably since then. It is estimated there is also up to 1000 Sika deer in Killarney National Park.^[2] Within the park they are found both on open upland areas and woodlands.^[4]

Bird species

^[21] The Park boasts a wealth of bird life, and is of ornithological importance because it supports a diverse range of birds. 141 bird species have been recorded in the park,^[29] including upland, woodland and wintering waterfowl species.^[6] Several species which are otherwise rare in Ireland are present, notably the woodland species redstart (1–2 pairs), wood warbler (1–2 pairs), and garden warbler (possibly up to 10 pairs). The red grouse and ring ouzel are on the IUCN Red List of species of high conservation concern (1–2 pairs each). The Greenland white-fronted goose, merlin, and peregrine are listed on Annex I of the EU Birds Directive.^[3] Other noteworthy species found in the park are the chough, nightjar, and osprey. The osprey sometimes passes through the park as it migrates between northern Africa and Scandinavia. Historical accounts and place names suggest that the osprey bred in the area in the past. Golden eagles once nested in the park, but were extirpated around 1900 as a result of disturbance, nest robbing, and persecution.^[29]

The most common bird species in upland areas are meadow pipits, ravens and European stonechats.^[4] Rare species are merlins (up to five pairs) and peregrine falcons (at least one pair).^[6]

Chaffinches and robins are the most common species in the woodlands.^[4] Other species that breed there include blackcaps and garden warblers. The rare redstart and wood warbler are thought to have a few breeding pairs in the park's woodlands.^[6]

Grey herons, little grebes, mallards, water rails, dippers and common kingfishers live on the park's water bodies.^[4]

Lough Leane, and the other lakes to a lesser extent, support wintering birds that travel south from higher latitudes.^[3] These species include redwing, fieldfare, golden plover and waterfowl such as teal, goldeneye, wigeon, pochard and whooper swan.^[29] The park's native bird populations are augmented by migrant species in both winter and summer. A small flock of Greenland white-fronted geese (Anser albifrons flavirostris) from the world population of approximately 12,000^[4] migrates to winter on boglands^[6] in the Killarney Valley within the park.^[4] The numbers of this bird that stay in the park are currently low, at less than twenty individuals. This population is important because it is the most southerly in Ireland and one of the few remaining populations remaining that feed entirely on bogland,^[6] and whose habitat almost entirely lies within a protected area.^[26]

Other wintering waterfowls are coot, cormorant, goldeneye, mallard, pochard, teal, and tufted duck. Other species that live on the lakes are the black-headed gull, little grebe, and mute swan.^[3]

Species that migrate from Africa in the summer include cuckoos, swallows, and swifts. Some species are vagrants that appear sporadically, for example when there is stormy weather or an unusually cold spell on the European continent.^[29]

The park is also the site for a project to reintroduce white-tailed eagles, which began in 2007 with the release of fifteen birds. The project will last a number of years with many more eagles being released. The species had become extinct in Ireland in the 19th century after persecution from landowners. Fifteen chicks will then be brought in annually for the following five years.^[30] Despite a poisoning incident in 2009, the program is continuing^[31] and birds introduced to the area have now been tracked to Wicklow and Donegal.

Fish species

The Lakes of Killarney contain many brown trout and an annual run of salmon. Rare species found in the lakes are Arctic char and Killarney shad.^[20] The lakes have natural stocks of brown trout and salmon that can be fished, subject only to usual Irish salmon license regulations.^[4]

The lakes contain Arctic char (Salvelinus alpinus L.), which is usually found much further north in sub-Arctic lakes.^[4] It's a relict species left behind in the area after the last Ice Age, and are consequently indicative of pristine environmental conditions. Although they were once widespread, they now are confined to isolated populations in inland freshwater lakes that have a suitable habitat. They are isolated in their respective lakes since the last Ice age. They are extremely sensitive to environmental changes when they are as far south as Ireland, where they are at the southern edge of their species range. The greatest threats to their survival in Ireland are introduced fish species, eutrophication, acidification and climate change. The rate of extinction of entire populations in Ireland has increased in recent decades.^[32]

The Killarney shad (or goureen) (Alosa fallax killarnensis) is a land-locked lake-dwelling subspecies of twaite shad, a mostly marine species. It is unique to the Lakes of Killarney. It is rarely seen because it feeds mainly on plankton and thus is rarely caught by fishers. It is listed in the Irish "Red Data Book" of threatened species.^[26] It is listed in Annex II of the EU Habitats Directive.^[6]

Invertebrates

Several unusual invertebrate species can be found in the Killarney valley. Some of these species, including the northern emerald dragonfly (Somatochlora arctica) and several caddisfly and stonefly species are usually found much further north in Europe. They are thought to be relict species that were left behind in Killarney after the last retreat of ice.^[26] The northern or moorland emerald dragonfly, the rarest Irish dragonfly, is confined to the park. It breeds in shallow pools in bogs.^[33]

The oak woods in the remote Glaism na Marbh valley are a stronghold for Formica lugubris Zett., a wood ant species that is rare both in the Killarney woods and in Ireland as a whole.^[13]

The Kerry Slug (Geomalacus maculosus) is a hiberno-lusitanean species. It emerges in Killarney's frequent wet weather to graze on lichens on rocks and tree trunks. It is reputedly the only slug capable of rolling itself into a ball. It is on both Annex II and Annex IV of the EU Habitats Directive.^[26]