Boho Caves
Encyclopedia
The Boho Caves are a selection of caves centred on the village of Boho, County Fermanagh
on the northern slopes of Belmore Mountain
. They encompass the main Boho Cave and the smaller Waterfall Cave and Upper and Lower Ravine Caves. The Boho Cave system is the sixth-longest cave system in Northern Ireland, is designated an Area of Special Scientific Interest
(ASSI #144) and is the only example of joint-controlled caves in Northern Ireland.
period, estimated to be around 325 million years old. The rock sequence exposed at Boho consists of the Glencar Limestone
Formation which is overlain by the Dartry Limestone Formation, composed of chert
y limestones and limestones and shale
s of the Carn Limestone Member. The Dartry Limestone is, in turn, overlain by the Meenymore Formation and the Glenade Sandstone
. The caves are formed within the Dartry Limestone. The main cave contains typical karst
features such as stalactite
s, stalagmite
s, cave curtains and flowstone
.
The water flowing through the Boho Caves originates from Aghanaglack River. After dry weather, the river sinks in the streambed well upstream of the caves and does not emerge until far downstream past the ravine. In wetter conditions, water flows into the cave system via several routes including the Main Sink entrance, which can sump and overflow into the nearby field shakeholes. It then exits the cave at the usual downstream resurgences, as well as the Upper and Lower Ravine caves (via bedding planes from the northern end of Boho Cave) and in particularly high floods, the Quarry entrance (see picture).
and Lyster Jameson definitely visited Boho parish in 1895 and investigated some of the caves, Martel's description makes it unclear as to whether they visited Boho Caves or nearby Pollnagollum Coolarkan. Boho quarry, in which there are a number of entrances to the cave, was active until the mid 1950s and many local people would have explored short sections of the cave during and before this time. The Yorkshire Ramblers explored Boho Caves in 1907 but it was not until the mid 1960s that a survey
of this complicated system was attempted by Dublin cavers. The system was extensively resurveyed by the Reyfad Group in the 1980s.
It is also recommended that the Upper Ravine area downstream of Boho quarry should NOT be visited under any circumstances because of roosting bats.
or Water Bats which roost in the Upper Ravine Cave.
Lass of Nottingham University (in Hazelton, 1974) made extensive faunal collections in Boho Caves which included the identification of the troglobitic
Collembolan . Chapman (1993) cites the collection of a stickleback
from Boho and the Field Shake Holes and Southern Series have been observed to support a large spider population . The strong draughts may bring trogloxene
s into the cave on which this population thrives. The record of the water beetle, , was of some interest at the time as there had been few Irish records of this spring and cave-dwelling species.
County Fermanagh
Fermanagh District Council is the only one of the 26 district councils in Northern Ireland that contains all of the county it is named after. The district council also contains a small section of County Tyrone in the Dromore and Kilskeery road areas....
on the northern slopes of Belmore Mountain
Belmore Mountain
Belmore Mountain is a hill in the townland of Gortgall, western County Fermanagh, Northern Ireland. With a summit roughly above sea level, it is the second highest point in Fermanagh, the highest being at Cuilcagh on the Northern Ireland–Republic of Ireland border in the south of the...
. They encompass the main Boho Cave and the smaller Waterfall Cave and Upper and Lower Ravine Caves. The Boho Cave system is the sixth-longest cave system in Northern Ireland, is designated an Area of Special Scientific Interest
Area of Special Scientific Interest
An Area of Special Scientific Interest or ASSI is a conservation designation denoting a protected area in Northern Ireland. ASSIs are the equivalent of Sites of Special Scientific Interest in the rest of the United Kingdom....
(ASSI #144) and is the only example of joint-controlled caves in Northern Ireland.
Geology and hydrology
The rock strata at Boho Caves date from the Asbian substage of the CarboniferousCarboniferous
The Carboniferous is a geologic period and system that extends from the end of the Devonian Period, about 359.2 ± 2.5 Mya , to the beginning of the Permian Period, about 299.0 ± 0.8 Mya . The name is derived from the Latin word for coal, carbo. Carboniferous means "coal-bearing"...
period, estimated to be around 325 million years old. The rock sequence exposed at Boho consists of the Glencar Limestone
Limestone
Limestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate . Many limestones are composed from skeletal fragments of marine organisms such as coral or foraminifera....
Formation which is overlain by the Dartry Limestone Formation, composed of chert
Chert
Chert is a fine-grained silica-rich microcrystalline, cryptocrystalline or microfibrous sedimentary rock that may contain small fossils. It varies greatly in color , but most often manifests as gray, brown, grayish brown and light green to rusty red; its color is an expression of trace elements...
y limestones and limestones and shale
Shale
Shale is a fine-grained, clastic sedimentary rock composed of mud that is a mix of flakes of clay minerals and tiny fragments of other minerals, especially quartz and calcite. The ratio of clay to other minerals is variable. Shale is characterized by breaks along thin laminae or parallel layering...
s of the Carn Limestone Member. The Dartry Limestone is, in turn, overlain by the Meenymore Formation and the Glenade Sandstone
Sandstone
Sandstone is a sedimentary rock composed mainly of sand-sized minerals or rock grains.Most sandstone is composed of quartz and/or feldspar because these are the most common minerals in the Earth's crust. Like sand, sandstone may be any colour, but the most common colours are tan, brown, yellow,...
. The caves are formed within the Dartry Limestone. The main cave contains typical karst
KARST
Kilometer-square Area Radio Synthesis Telescope is a Chinese telescope project to which FAST is a forerunner. KARST is a set of large spherical reflectors on karst landforms, which are bowlshaped limestone sinkholes named after the Kras region in Slovenia and Northern Italy. It will consist of...
features such as stalactite
Stalactite
A stalactite , "to drip", and meaning "that which drips") is a type of speleothem that hangs from the ceiling of limestone caves. It is a type of dripstone...
s, stalagmite
Stalagmite
A stalagmite is a type of speleothem that rises from the floor of a limestone cave due to the dripping of mineralized solutions and the deposition of calcium carbonate. This stalagmite formation occurs only under certain pH conditions within the underground cavern. The corresponding formation on...
s, cave curtains and flowstone
Flowstone
Flowstones are composed of sheetlike deposits of calcite formed where water flows down the walls or along the floors of a cave. They are typically found in "solution", or limestone caves, where they are the most common speleothem. However, they may form in any type of cave where water enters that...
.
The water flowing through the Boho Caves originates from Aghanaglack River. After dry weather, the river sinks in the streambed well upstream of the caves and does not emerge until far downstream past the ravine. In wetter conditions, water flows into the cave system via several routes including the Main Sink entrance, which can sump and overflow into the nearby field shakeholes. It then exits the cave at the usual downstream resurgences, as well as the Upper and Lower Ravine caves (via bedding planes from the northern end of Boho Cave) and in particularly high floods, the Quarry entrance (see picture).
History of exploration
Although Édouard-Alfred MartelÉdouard-Alfred Martel
, the 'father of modern speleology', was a world pioneer of cave exploration, study, and documentation...
and Lyster Jameson definitely visited Boho parish in 1895 and investigated some of the caves, Martel's description makes it unclear as to whether they visited Boho Caves or nearby Pollnagollum Coolarkan. Boho quarry, in which there are a number of entrances to the cave, was active until the mid 1950s and many local people would have explored short sections of the cave during and before this time. The Yorkshire Ramblers explored Boho Caves in 1907 but it was not until the mid 1960s that a survey
Cave survey
A cave survey is a map of all or part of a cave system, which may be produced to meet differing standards of accuracy depending on the cave conditions and equipment available underground. Cave surveying and cartography, i.e. the creation of an accurate, detailed map, is one of the most common...
of this complicated system was attempted by Dublin cavers. The system was extensively resurveyed by the Reyfad Group in the 1980s.
Access
Boho is a cave much used by guided educational parties studying the local environment and by casual visitors, but exploration should never be undertaken lightly. In wet weather the narrow passages flood quickly and at these times the cave is extremely dangerous and should be avoided. Heavy flood pulses have been known to inundate the cave up to 24 hours after heavy rain has ceased, and the entire system is known to flood to the roof in under an hour.It is also recommended that the Upper Ravine area downstream of Boho quarry should NOT be visited under any circumstances because of roosting bats.
Fauna
The main biospeleological interest in the Boho area is the population of approximately 50 Daubenton'sDaubenton's bat
Daubenton's Bat, Myotis daubentonii, is a Eurasian bat with quite short ears. It ranges from Britain to Japan and is considered to be increasing its numbers in many areas.The name commemorates the French naturalist Louis-Jean-Marie Daubenton....
or Water Bats which roost in the Upper Ravine Cave.
Lass of Nottingham University (in Hazelton, 1974) made extensive faunal collections in Boho Caves which included the identification of the troglobitic
Troglobite
Troglobites are small cave-dwelling animals that have adapted to their dark surroundings. Troglobite species include spiders, insects, fish and others. They live permanently underground and cannot survive outside the cave environment. Troglobite adaptations and characteristics include a heightened...
Collembolan . Chapman (1993) cites the collection of a stickleback
Stickleback
The Gasterosteidae are a family of fish including the sticklebacks. FishBase currently recognises sixteen species in the family, grouped in five genera. However several of the species have a number of recognised subspecies, and the taxonomy of the family is thought to be in need of revision...
from Boho and the Field Shake Holes and Southern Series have been observed to support a large spider population . The strong draughts may bring trogloxene
Trogloxene
Trogloxenes are species which live close to caves or at the very entrance of the cave. Cliff swallows, cave swallows, cave swiftlets, reticulated pythons, rats, bats, bears, raccoons and humans are considered to be trogloxenes...
s into the cave on which this population thrives. The record of the water beetle, , was of some interest at the time as there had been few Irish records of this spring and cave-dwelling species.
See also
- Caves of the Tullybrack and Belmore hillsCaves of the Tullybrack and Belmore hillsThe Caves of the Tullybrack and Belmore hills can be found in south-west County Fermanagh, Northern Ireland. It is mainly within Boho parish. The region is also described as the West Fermanagh Scarplands by environmental agencies and shares many similar karst features with the nearby Marble Arch...
- List of caves in the United Kingdom
- List of caves