Horton Plains is located on the southern plateau of the central highlands of Sri Lanka.
[2] The peaks of
Kirigalpoththa (2,389 metres (7,838 ft)) and
Thotupola Kanda (2,357 metres (7,733 ft)), the second and the third highest of Sri Lanka, are situated to the west and north respectively. The park's
elevation ranges from 2,100–2,300 metres (6,900–7,500 ft).
[3] The rocks found in the park belong to the Archaean age and belong to the high series of the
Precambrian era and are made up of
Khondalites,
Charnockites and granitic gneisses.
[4][5] The
soil type is of the red-yellow
podsolic group and the surface layer is covered with decayed organic matter.
[4]
The mean annual rainfall is greater than 2,000 millimetres (79 in). Frequent cloudy cover limits the amount of sunlight that is available to plants. The mean annual temperature is
13 °C (55 °F) but the temperature varies considerably during the course of a day, reaching as high as
27 °C (81 °F) during the day time, and dipping as low as
5 °C (41 °F) at night. During the
southwest Monsoon season, the wind speed sometimes reaches
gale force. Although some rain falls throughout the year, a dry season occurs from January–March. The ground
frost is common in February.
Mist can persist in the most of the day during the wet season.
[6] Many pools and waterfalls can be seen in the park, and Horton Plains is considered the most important
watershedin Sri Lanka.
[2] The Horton Plains are the
headwaters of important rivers such as the
Mahaweli,
Kelani, and
Walawe.
[2] The plains also feeds Belihul Oya, Agra Oya, Kiriketi Oya, Uma Oya, and Bogawantalawa Oya.
[6]Due to its high elevation,
fog and cloud deposit a considerable amount of
moisture on the land. Slow moving streams,
swamps, and waterfalls are the important wetland habitats of the park.
History
The original name of the area was Maha Eliya Thenna (මහ එළිය තැන්න - "great open plain"). But in the British period the plains were renamed after
Sir Robert Wilmot-Horton, the
British governor of Ceylon from 1831 to 1837, who travelled to the area to meet the Ratemahatmaya of Sabaragamuwa in 1836,
[4] in 1834 by Lt William Fisher of the
78th Regiment and Lt. Albert Watson of the
58th Regiment, who 'discovered' the plateau.
[7] Stone tools dating back to
Balangoda culture have been found here. The local population who resided in the lowlands ascended the mountains to mine gems, extract
iron ore, construct
irrigational canaland fell trees for timber. A 6-metre (20 ft)
pollen core extracted from a mire revealed that in the late
quaternaryperiod the area had a semi-arid climate and a species-restricted plant community.
[8]
Flora
The vegetation of the park is classified into two distinctive groups, 2,000 hectares (7.7 sq mi) of wet
patana (Sinhalese for "montane
grasslands") and 1,160 hectares (4.5 sq mi) of subtropical montane evergreen forests.
[2] Nearly 750 species of plants belonging to 20 families have been recorded from the park. The forest
canopy reaches the height of 20 metres (66 ft) and features
Calophyllum walkeri, forming communities with varieties of
Myrtaceae species such as
Syzygium rotundifolium, and
S. sclerophyllum, and
Lauraceae members including
Litsea,
Cinnamomum, and
Actinodaphne speciosa.
[4] The
undergrowthlayer is characterised by
Strobilanthes spp. The thickness of the
Strobilanthes vegetation hinders the development of a herb layer. Dwarf bamboo species such
Indocalamus and
Ochlandra also found in the undergrowth layer.
Rhodomyrtus tomentosa bushes specially grow in forest margin and near the mountain peaks. Species such as
Gordonia and
Rhododendron arboreum have spread to Sri Lanka, along the
Western Ghats of
South India from the
Himalayas and are now common. Nearly 54
woody plant species have been recorded from the park, of which 27 (50%) are endemic to Sri Lanka.
[4]
Frequent fire and
grazing characterises
Plagioclimax communitiesof the grassland flora.
[2] Grasslands are dominated by
Arundinella villosa and
Chrysopogon zeylanicus. Waterlogged
swamps or slow moving streams are found in low lying areas, and
macrophytessuch as
Aponogeton jacobsenii,
sedge species
Isolopis fluitansand
Utricularia spp. are found near the slow moving streams. The
bamboo Chimonobambusa densifolia thrive along the banks of the streams, and near the swampy areas grass species such as
Juncus prismatocarpus,
Garnotia mutica,
Eriocaulon spp. and
Exacum trinervium are common.
Tussock grasses such as
Chrysopogon zeylanicus and
Cymbopogon confertiflorus are found in the wet hollows.
[4] Herbaceous flora of the grasslands include temperate species including
Ranunculus,
Pedicularis,
Senecio,
Gentiana and
Alchemilla and also tropical species such as
Eriocaulon and
Ipsea speciosa (a rare endemic daffodil orchid). The most widespread
boreal herbaceous plants of the park are
Viola,
Lobelia,
Gaultheria,
Fragaria, and
Plantago.
[9]
Tree trunks and branches are ornamented with many species of
ferns,
Lycopodium,
lichens, and
orchids.
[6]Old man's beard (
Usnea barbata) hanging from branches adds to the beauty of the forests. About 16 of the orchid species being endemic. Other notable plants include shrubs such as
Rhodomyrtus tomentosa,
Gaultheria fragrantissima, herbs,
Exacum trinervium,
E. walkeri,
Drosera indica, and
tree ferns Cyatheaspp.
[2] Anzia, a foliose lichen genus belonging to
Parmeliaceae family, which had not been recorded in Sri Lanka previously, was discovered here in 2007.
[3] There are conflicting views on how the grasslands of the park came into being, whether man-made or natural. It is now believed that the grasslands on the dry slopes were created by forest clearance and fires while grasslands in low lying areas were naturally created by wet conditions,
frost and
soil erosion.
[4]
Twisted trees are a common sight due to due to the speedy wind
Fauna
The vertebrate fauna of the region includes 24 species of mammals, 87 species of birds, nine species of reptiles and eight species of amphibians.
[2] The
Sri Lankan Elephant disappeared from the region in the 1940s at the latest.
[4] At present, the largest and the most commonly seen mammal is the
Sambar Deer. Some research findings estimate the population of Sambar Deer to be around 1500 to 2000, possibly more than the carrying capacity of the plains.
[6] Other mammal species found in the park include
Kelaart's Long-clawed Shrews,
Toque Macaques,
Purple-faced Langurs,
Rusty-spotted Cat,
Sri Lankan Leopards,
Wild boars,
Stripe-necked Mongooses,
Sri Lankan Spotted Chevrotains,
Indian Muntjacs, and
Grizzled giant squirrels.
Fishing Cats and
European Otters visit the wetlands of the park to prey on aquatic animals.
[2]A subspecies of
Red Slender Loris, the Horton Plains Slender Loris (
Loris tardigradus nycticeboides formerly sometimes considered as
Loris lydekkerianus nycticeboides) is found only in highlands of Sri Lanka and is considered one of the world's most endangered primates.
[10][11] In July 2010 a group of researchers from the
Zoological Society of London was able to photograph the mammal for the first time.
[12]
Along with
Ohiya, Pattipola and
Ambewela, Horton Plains forms one of the
Important Bird Areas (IBAs) in Sri Lanka.
[13] Together with the adjacent
Peak Wilderness Sanctuary, Horton Plains contains 21 bird species which occur only on Sri Lanka. Four,
Sri Lanka Blue Magpie,
Dull-blue Flycatcher,
Sri Lanka White-eye, and
Sri Lanka Wood Pigeon, occur only in Horton plains, while other endemic species include
Sri Lanka Spurfowl,
Sri Lanka Junglefowl,
Yellow-fronted Barbet,
Orange-billed Babbler,
Sri Lanka Bush Warbler, and
Sri Lanka Whistling-thrush. Many birds
migrate here in winter including
swiftlets, and
Alpine Swift.
Crested Serpent Eagle,
Mountain Hawk-Eagle,
Black-winged Kite, and
Peregrine Falcon are among the
birds of prey found in Horton Plains.
Harriers are among the migratory raptors.
[2] This is a key wildlife area. All six highland endemic birds are found here, including
Dull-blue Flycatcher,
Sri Lanka White-eye,
Sri Lanka Wood Pigeon, and
Sri Lanka Bush Warbler.
Yellow-eared Bulbul and
Black-throated Munia are widespread throughout the highlands.
[4]
Sri Lanka is considered a herpetological paradise in the world.
[6] Possibly about 15 amphibian species inhabit the park. Among them are
Microhyla zeylanica,
Ramanella palmata,
Fejervarya greenii,
Rana gracilis,
Philautus alto,
Philautus femoralis,
Philautus frankenbergi,
Philautus microtympanum,
Philautus schmarda, and
Polypedates eques. De Silva has observed six endemic reptiles from the plains. They are
Calotes nigrilabris,
Rhino Horn Lizard,
Cophotis ceylanica,
Lankascincus taprobanensis,
Common rough-sided snake, and
Rat snake. Two fish species found in the park,
common carp and
rainbow trout; both are
introduced species.
[2] Horton Plains is also home to many endemic
crustaceans including
Caridina singhalensis and
Perbrinckia species. The endemic freshwater shrimp
Caridina singhalensis is found only in streams that have a temperature of less than 15 degrees C and is now restricted to only a stretch of 10 km of one stream.
[14]
Threats and conservation management
Horton Plains was a part of a large system of plains and forest cover that included Agra-Bopats, Moon Plains and Elk Plains.
[4] Between 1831 and 1948, it became a Sambar deer hunting ground. Elephants and Wild Boar were also hunted to a lesser extent. During this period lower slopes were cleared initially for coffee and then for
tea plantations. As a result, Horton Plains and Peak Wilderness became isolated from other forest and grassland areas. Potatoes were cultivated in the grasslands but planting ceased in 1977. After being declared a National Park, these areas were reinstated as grasslands. Tourism-related issues such as plant removal, littering,
fires and noise pollution are major conservation issues.
[2] Gem mining,
timber logging, the collection of plants for ornamental and
medicinal purposes, encroachment,
poaching and vehicle traffic are the other threats. The spread of
invasive alien species such as Gorse (
Ulex europaeus),
brackens, and
Pennisetum spp. threaten the native flora. The introduced rainbow trout may have affected endemic species of fish, amphibia and crustaceans.
[4]
Some Sambar deer have died due to eating polythene litter that blocked their food passages, and visitors are banned from bringing polythene into the park.
[15] Sambar have benefited from the introduced
Pennisetumgrass species.
[16]
A recent threat, first reported in 1978, is
forest dieback.
[4] In some areas, especially in the peripheral region, this has been severe with nearly a 50% in vegetation. Water deficiency has been attributed as the main cause of dieback as
droughts are becoming more frequent. Regrowth of forest is hindered by frost which is increasingly severe. The forest dieback has affected 22 species of plants with
Calophyllum walkeri being the most affected.
[17] A study has suggested that low Calcium causes
soil acidification and increased toxicity caused by metallic elements such as Aluminium may be causing the dieback.
Leaching of nutrients and the resulting imbalance in soil
micronutrients may also be contributing to the dieback.
[18]
Tourist attractions
World's End is a major attraction
Horton Plains is a popular tourist destination, with World's End being the key attraction.
[2] In the six months ending in August 2009, Horton Plains National Park earned a revenue of Rs. 20.1 million (
US$ 0.17 million).
[19] The park is accessed by the Nuwara Eliya-Ambewela-Pattipola and
Haputale-
Boralanda roads, and there are railway stations at
Ohiya and
Ambewela. World's End is a sheer
precipice with a 870 m (2,854 ft) drop.
[6] It is situated at the southern boundary of the park. Another cliff known as the Lesser World's End of 270 m (886 ft) is located not far from World's End.
Baker's Falls, a waterfall formed by Belihul Oya, a tributary of the Walawe River is named after Sir
Samuel Baker, a hunter and explorer
[20] who attempted to establish a European agricultural settlement at
Nuwara Eliya. The falls are 20 metres (66 ft) high. Slab Rock Falls is another well known waterfall in the plains.
