Radford Cave, in Hexton Wood, near Hooe, Plymouth, Devon is a small phreatic cave of some ecological interest. It has been known to speleologists and others for many years [1] and a plan was published in 1953. [2]
It is a popular place for adventure-seekers and those new caving, since it provides an easy round trip and is it difficult to get lost. However, there are occasional incidents when the inept, over-enthusiastic or inexperienced become stuck. There was, for example, a small drama reported on the front page of the Western Morning Herald, as well as in the Daily Telegraph where a Coldstream Guards instructor became wedged by his hips, face down, and had to be chipped free.
The cave is locked to protect the bats.
The cave is situated in an old quarry in Devonian limestone. Its total passage length is around 600m. Cave temperature is 12-13 Celsius. Air moves into the cave during daylight hours and out during the hours of darkness. The maximum passage height is about 9m with humidity varying within the cave from 83 to 98%, but it is usually at the top of the range. Local building may have had an effect on the ecology of the cave. [3] The pools of water within the cave are at a pH of 7.7. Organic matter comprises less than 6% of the cave clay so this is a poor food for invertebrates.
Various zoologists with an interest in cave-dwelling creatures have worked n the cave. Both the Greater Horseshoe Bat and the Lesser Horseshoe Bat have been recorded inside. The invertebrates have been documented by various collectors, and records are held by the British Cave Research Association. The isopod Androniscus dentiger (Trichoniscidae) and acari Eugamasus loricatus (Parasitidae) are found throughout the dark zone of the cave. The commonest collembola are the lightly pigmented troglophiles Heteromurus nitidus; the white troglobite Pseudosinella dobati also inhabits the cave. [4] Both are 1.7mm long. Other Collembola have been recorded including Entomobrya muscorum, Schaefferia emucronata, S. lindbergi, Onychiurus armatus, Neelus murinus, Arrhopalites caecus, and A. pymaegus. Collembola are particularly abundant in the Red Corridor section of the cave where humidity is generally at 93-94%. The spider Meta menardii (shown) inhabits the entrance and threshold zones of the cave and is sometimes found in the dark zone.
The greater horseshoe bat is an insectivorous bat of the genus Rhinolophus. Its distribution covers Europe, Northern Africa, Central Asia and Eastern Asia. It is the largest of the horseshoe bats in Europe and is thus easily distinguished from other species. The species is sedentary, typically travelling up to 30 kilometres (19 mi) between the winter and summer roosts, with the longest recorded movement being 180 km (110 mi). The frequencies used by this bat species for echolocation lie between 69–83 kHz, have most energy at 81 kHz and have an average duration of 37.4 ms.
The lesser horseshoe bat is a type of small European and North African insectivorous bat, related to its larger cousin, the greater horseshoe bat. As with all horseshoe bats, the species gets its name from its distinctive horseshoe-shaped noseleaf.
The Jamaican, common or Mexican fruit bat is a fruit-eating bat native to Mexico, through Central America to northwestern South America, as well as the Greater and many of the Lesser Antilles. It is also an uncommon resident of the Southern Bahamas. Populations east of the Andes in South America are now usually regarded a separate species, the flat-faced fruit-eating bat. The distinctive features of the Jamaican fruit bat include the absence of an external tail and a minimal, U-shaped interfemoral membrane.
Ankarana Special Reserve in northern Madagascar was created in 1956. It is a small, partially vegetated plateau composed of 150-million-year-old middle Jurassic limestone. With an average annual rainfall of about 2,000 millimetres (79 in), the underlying rocks have been eroded to produce caves and feed subterranean rivers—a karst topography. The rugged relief and the dense vegetation have helped protect the region from human intrusion.
Troglofauna are small cave-dwelling animals that have adapted to their dark surroundings. Troglofauna and stygofauna are the two types of subterranean fauna. Both are associated with subterranean environments – troglofauna are associated with caves and spaces above the water table and stygofauna with water. Troglofaunal species include spiders, insects, myriapods and others. Some troglofauna live permanently underground and cannot survive outside the cave environment. Troglofauna adaptations and characteristics include a heightened sense of hearing, touch and smell. Loss of under-used senses is apparent in the lack of pigmentation as well as eyesight in most troglofauna. Troglofauna insects may exhibit a lack of wings and longer appendages.
Cave-dwelling insects are among the most widespread and prominent troglofauna, including troglobites, troglophiles, and trogloxenes. As a category of ecological adaptations, such insects are significant in many senses, ecological, evolutionary, and physiological.
Bakers Pit is a phreatic maze cave system near Buckfastleigh, Devon, England.
The bicolored roundleaf bat is a species of bat in the family Hipposideridae found in Indonesia, Malaysia, the Philippines, Thailand, and Timor-Leste. This bat inhabits caves, rock crevices and tunnels among lowland forests. They roost in large numbers and consume mostly small winged insects. Their navigation and hunting skills come from the use of echolocation. Its leafnose is used to release ultrasonic shouts to distinguish its surroundings. Echolocation is also used to distinguish other species based on their wingbeat and size. The habitat of this bat decides the color of its fur. Bleaching fumes of a cave environment will cause an orange colored fur. Those who inhabit a well-ventilated roost will be a light brown color.
The Andaman horseshoe bat is a species of bat in the family Rhinolophidae. It is endemic to the Andaman Islands. During the day, it roosts in caves, but may also choose tree hollows.
The convex horseshoe bat is a species of bat in the family Rhinolophidae. It is found in Malaysia and Laos.
The smaller horseshoe bat is a species of bat in the family Rhinolophidae. It is found in Australia and Papua New Guinea.
Swinny's horseshoe bat is a species of bat in the family Rhinolophidae. In English, R. swinnyi is commonly referred to as Swinny's horseshoe bat. In Afrikaans, it is commonly referred to as Swinny se saalneusvlermuis. This species belongs to the African clade. R. swinnyi was discovered by an African collector H. H. Swinny. They have been recorded in Angola, Republic of the Congo, Mozambique, South Africa, Tanzania, Zambia, Zimbabwe, and Malawi.
The Magura Cave is located in north-western Bulgaria close to the village of Rabisha, 25 km (16 mi) from the town of Belogradchik in Vidin Province.
Springtails (Collembola) form the largest of the three lineages of modern hexapods that are no longer considered insects. Although the three orders are sometimes grouped together in a class called Entognatha because they have internal mouthparts, they do not appear to be any more closely related to one another than they are to all insects, which have external mouthparts.
Jane Wilson-Howarth BSc, CF, MSc, BM, DCH, DCCH, DFSRH, FFTM RCPS is a British physician, lecturer and author. She has written three travel health guides, two travel narratives, a novel and a series of wildlife adventures for children. She has also contributed to anthologies of travellers tales, has written innumerable articles for non-specialist readers, and many scientific/academic papers.
Coedydd Capel Dyddgen is a Site of Special Scientific Interest in Carmarthen & Dinefwr, Wales.
Subterranean fauna refers to animal species that are adapted to live in an underground environment. Troglofauna and stygofauna are the two types of subterranean fauna. Both are associated with hypogean habitats – troglofauna is associated with terrestrial subterranean environment, and stygofauna with all kind of subterranean waters.
Yagodinska Cave is a cave in the Rhodope Mountains, southern Bulgaria. It is included in the 100 Tourist Sites of Bulgaria under № 89. It is named after the homonymous village nearby. With a total length of 10,500 m, Yagodinska is the third longest cave in the country after Duhlata and Orlova Chuka and the longest in the Rhodopes. Yagodinska Cave is home to 11 species of bats.
Ojo Guareña is a karst complex located in the Cantabrian Mountains of Castile and Leon, Spain, declared a natural monument by the government of Castile and Leon in 1996. It is composed of over 90 kilometres (56 mi) of galleries and passages within an area of some 13,850 hectares. The limestone formation containing the system is approximately 100 metres (330 ft) thick and sits on a massive water-resistant layer of marl. The caves were formed in the limestone by erosion sometime within the Coniacian Age. Ojo Guareña was considered the greatest karst system of the Iberian Peninsula until 2009, when a significant length of new passages was discovered in the Mortillano system.
The Kogelbeen Cave forms part of eight caves on the dolomitic Ghaap Plateau of the Northern Cape, South Africa. It is commonly known as Kogelbeengrotte in Afrikaans. The cave is located on Kogelbeen Farm in Pixley ka Seme District Municipality. It is the longest known cave in the Northern Cape with a length of 788 meters. The Kogelbeen Cave has a diverse fauna with over 39 species living in five life zones within the cave.