Red List habitat classification > RLH - Sparsely vegetated habitats > RLH1.1 Cave

Cave

Quick facts

Red List habitat type code RLH1.1
Threat status
Europe Least Concern
EU Least Concern
Relation to
Source European Red List habitat factsheet
European Red List of habitats reports
European Red List of habitats (Excel table)

Summary

The habitat includes natural caves and cave systems with their associated cave water basins. Caves and their associated waters harbor various biotic communities (plants, animals, fungi and algae) that are restricted to them (troglobiont organisms), or are physiologically and ecologically capable of conducting their entire life cycle inside them (troglophile organisms), or are dependent on them for part of their life cycle (subtroglophile organisms). The habitat is very diverse, but is mainly formed by the karst processes at the calcareous rocks. The caves also vary in size and extent. Their exterior part (cave entrances) includes the twilight zone where light penetrating from the outer world is sufficient to permit human vision. The habitat is rarely vegetated, and in this case dominant plants are mostly algae and mosses, and sometimes also vascular plant species such as  Cortusa matthioli occur. At the interior part of the caves, light is completely lacking. This part is with or without troglobiont or troglophile organisms. The vertebrate fauna includes unique amphibians such as Proteus anguinus in the Adriatic karst systems and bats. Bats are not typical troglobionts because they use the caves only for breeding and wintering. Invertebrate species belong to a limited number of groups, and include remarkable relict species from Gastropoda, Opiliones, Chilopoda (Lithobiidae), Collembola, Coleoptera (Bathysciinae and Trechinae subfamilies) among the terrestrial fauna and Turbellaria, Gastropoda and Urodela, among the aquatic fauna. They form characteristic fauna communities, which are essentially restricted to caves in temperate regions. The majority of the rich in invertebrates’ caves are situated in Southern and South-Eastern Europe (Mediterranean and Balkan Peninsula). The caves may be of different types: dry caves or caves crossed by permanent or temporary watercourses (habitat C6.1),  warm caves and caves humidified by geothermal waters, relatively warm deoxygenated caves, rich in carbon dioxide and sulphur vapor or methane and hydrogen sulphide harboring relict thermophile invertebrate fauna. In the regions with active volcanic activities there are caves formed in lava flows by open-ended tubes or passages resulting from the cooling of the surface (whose molten interior continued to flow). Some large lava tubes on the Canary Islands harbor unique communities of invertebrates, in particular, decapod crustaceans. Caves near the coast, which may contain salt water and can be colonized by specialized (anchihaline) communities, whether or not connected to the sea, are included to the marine habitats.

Indicators of quality:

Caves in good condition are considered the ones that are without any anthropogenic structures and are impacted only by natural processes. These are dynamic systems due to water erosion and collapse of rocks. The main threat is from rehabilitation and lighting for tourist attraction, which would allow non-typical animal and plant species to invade the cave’s interior. Plants growing in caves are equipped with electric lights  known as “lampenflora”. They tend to be less vibrant in color and somewhat disfigured. Typically, lampenflora are mosses, ferns and algae. In caves that are lit constantly by lamps, these invasive plants can cause problems to the cave's natural structure or any prehistoric wall art present. It also may form a threat to troglophile and troglobiont fauna. Indicators of good quality are:

  • Stable water regime and annual course of temperature
  • Absence of invasive organisms
  • No disturbance by humans

Characteristic species
For full habitat description, please download the habitat factsheet.

Threat status

Synthesis of Red List assessment

Only limited data were available for calculation. Some countries with expected karst systems are missing, e.g. the localities in Albania, Bosnia and FYROM (Former Yugoslavian Republic of Macedonia), some data are questionable, e.g. 4 km2 in Romania and 15,000 km2 in Austria. Several other countries gave only number of caves, e.g. Germany and Poland. All this information makes the final calculation of trends in quality and quantity, range (EOO) and distribution (AOO) complicated. It is generally very subjective to decide, which part of the cave should be considered as the habitat H1.1 (like cave entrances with evident occurrence of plants or animals), and which part could be considered as a cave without biota.
EU
Red List Category Red List Criteria
Least Concern -
Europe
Red List Category Red List Criteria
Least Concern -

Confidence in the assessment

low
Red List of habitat categories and criteria descriptions

Pressures and threats

  • Agriculture
    • Fertilisation
  • Mining, extraction of materials and energy production
    • Mining and quarrying
    • Sand and gravel quarries
    • Open cast mining
  • Transportation and service corridors
    • Roads, motorways
    • Railway lines, TGV
    • Tunnel
  • Human intrusions and disturbances
    • Mountaineering & rock climbing
    • Speleology
    • Recreational cave visits
  • Pollution
    • Groundwater pollution by mine water discharges
  • Geological events, natural catastrophes
    • Earthquake
    • Collapse of terrain, landslide

Habitat restoration potential

The development of large caves is a process for hundreds of thousands of years. It is a process which takes place constantly but very slowly. The natural recovery of habitats connected with caves (plants, animals) need shorter time, but probably many hundreds of years. Closure of caves and galleries may prevent caves to be inhabited by bats; the opening of these gives space to very quick settlement.

Trends in extent

Average current trend in quantity

Stable Stable
EU28 EU28+

Trends in quality

Average current trend in quality

Decreasing Decreasing
EU28 EU28+

Conservation and management needs

Caves in the less accessible mountainous sites do not require special conservation interventions, since the conditions are stable and also the trends in quality and quantity are stable. Caves at lower altitudes, where there might be certain conflicts with human activities, should be strictly protected and taken into account when spatial land use planning (transportation, construction works) is taking place. In areas with intensive agricultural activities the surface and ground waters should be protected.

List of conservation and management needs

  • Measures related to agriculture and open habitats
    • Maintaining grasslands and other open habitats
  • Measures related to urban areas, industry, energy and transport
    • Specific management of traffic and energy transport systems

Distribution

For each habitat a distribution map was produced from a wide variety of sources indicating known and potential occurrences of the habitat in 10x10 km grids within Europe. Occurrences in grid cells were given in two classes: actual distribution from relatively reliable sources (surveys, expert knowledge), and potential distribution based on models or less reliable indicators. Please download the fact sheet to see the map.

Geographic occurrence and trends

EU28 Present or presence uncertain Current area of habitat (Km2) Recent trend in quantity (last 50 years) Recent trend in quality (last 50 years)
Bulgaria Present 19 Unknown Decreasing
Hungary Present 180 Stable Stable
Slovakia Present 407 Stable Stable
Austria Present 15000 Stable Stable
Czech Republic Present Unknown Stable Stable
France mainland Present 5800 Stable Stable
Corsica Present 5800 Stable Stable
Germany Present Unknown Decreasing Stable
Italy mainland Present 191 Unknown Unknown
Sardinia Present 191 Unknown Unknown
Sicily Present 191 Unknown Unknown
Portugal mainland Present Unknown Unknown Unknown
Portugal Azores Present Unknown Unknown Unknown
Madeira Present Unknown Unknown Unknown
Savage Islands Present Unknown Unknown Unknown
Spain mainland Present 360 Stable Stable
Balearic Islands Present 360 Stable Stable
Canary Islands Present 360 Stable Stable
Ireland Present Unknown Stable Stable
Belgium Present 0.5 Stable Stable
Finland mainland Present Unknown Unknown Unknown
Greece (mainland and other islands) Present Unknown Unknown Stable
Crete Present Unknown Unknown Stable
East Aegean Present Unknown Unknown Stable
Romania Present 4 Stable Stable
Poland Present Unknown Stable Stable
Aland Islands Present Unknown Unknown Unknown
EU28 + Present or presence uncertain Current area of habitat (Km2) Recent trend in quantity (last 50 years) Recent trend in quality (last 50 years)
Switzerland Present 12 Stable Stable
Former Yugoslavian Republic of Macedonia (FYROM) Present Unknown Unknown Unknown
Bosnia and Herzegovina Present 10 Decreasing Decreasing

Extent of Occurrence, Area of Occupancy and habitat area

Extent of Occurrence (EOO) (Km2) Area of Occupancy (AOO) Current estimated Total Area Comment
EU28 8498200 1425 >22000 area data is uncertain
EU28+ 3700 >22000 AOO and EOO incl. potential distribution
AOO = the area occupied by a habitat measured in number of 10x10 km grid cells.
EOO = the area (km2) of the envelope around all occurrences of a habitat (calculated by a minimum convex polygon).

Characteristic species

The full list of characteristic species and genus are available above from the Summary. The species available in the EUNIS database are shown here.
Amphibians Proteus anguinus
Flowering Plants Arabis nova
Flowering Plants Asperugo procumbens
Flowering Plants Chenopodium foliosum
Flowering Plants Cortusa matthioli
Flowering Plants Galium spurium
Flowering Plants Hackelia deflexa
Flowering Plants Hymenolobus pauciflorus
Flowering Plants Saxifraga arachnoidea
Flowering Plants Sisymbrium austriacum
Mammals Eptesicus serotinus
Mammals Hypsugo savii
Mammals Miniopterus schreibersii
Mosses & Liverworts Eucladium verticillatum
Mosses & Liverworts Fissidens cristatus
Mosses & Liverworts Isopterygium elegans
Mosses & Liverworts Pohlia nutans
Mosses & Liverworts Schistostega pennata
Species scientific name English common name Species group
Proteus anguinus Olm Amphibians
Arabis nova Flowering Plants
Asperugo procumbens Flowering Plants
Chenopodium foliosum Flowering Plants
Cortusa matthioli Flowering Plants
Galium spurium Flowering Plants
Hackelia deflexa Flowering Plants
Hymenolobus pauciflorus Flowering Plants
Saxifraga arachnoidea Flowering Plants
Sisymbrium austriacum Flowering Plants
Eptesicus serotinus Serotine Mammals
Hypsugo savii Savi's pipistrelle Mammals
Miniopterus schreibersii Schreiber's Bat Mammals
Eucladium verticillatum Mosses & Liverworts
Fissidens cristatus Mosses & Liverworts
Isopterygium elegans Mosses & Liverworts
Pohlia nutans Mosses & Liverworts
Schistostega pennata Mosses & Liverworts

Vegetation types

Relation to vegetation types (syntaxa)

Not available

Other classifications

This habitat may be equivalent to, or broather than, or narrower than the habitats or ecosystems in the following typologies.
Classification Code Habitat type name Relationship type
EUNIS Habitat Classification 200711 H1.1 Cave entrances wider
EUNIS Habitat Classification 200711 H1.3 Dark underground passages wider
EUNIS Habitat Classification 200711 H1.2 Cave interiors wider
EUNIS Habitat Classification 200711 H1.4 Lava tubes wider
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