04H1
Artificial galleries
Relationships with habitat classifications. EUNIS: H1.7 Disused underground mines and tunnels; PAL. CLASS.: 88 Mines and underground passages.
Conservation status. None.
Category. Vulnerable [VU – A2 C1 D3 E1 H3 J L2].
General characteristics. Several thousand artificial galleries exist in Bulgaria but there is no unified data base for their number, distribution and classifications. They are found mainly in the mountain regions, dug through during different historical times and for different purposes. The oldest galleries date back to the ancient Thracian times and are associated mainly with gold exploitation (e.g. the Ini-Kler gallery, Kardzhali district, developed in I–III centuries A.D.). The length of the galleries can vary from tens to hundreds of meters. During Roman times and the Middle Ages, galleries were dug for ore exploitation, especially iron. Hundreds of kilometres of galleries were built after the establishment of the Third Bulgarian Kingdom, and the quick development of the mining industry. Artificial galleries of different lengths have also been dug for water derrivations, geological studies, military sites, tunnels, etc.
The microclimatic conditions in the artificial galleries are very close to those in the caves and depend on the length, number of entrances and their position, the presence of running water and the depth of the galleries. After their digging through the galleries have become a part of the underground ecosystem as a result of the transportation and migration of organisms through the fissures and pores in the rocks as well as through intensive transportation of water within the hydro-geological basin. Similarly to the caves, this habitat is energetically fully dependant on the above-ground environment due to the absence of sunlight and photosynthesizing plants. The water is the main vector of nutritional substances such as detritus, plant parts and dead organisms. The animals that penetrate underground, mainly mammals, also contribute to the enrichment of the environment with nutritional substances through their excrements and other by-products of their life activities. Relatively shortly after they are dug through the galleries can be colonized by typical underground terrestrial and water fauna, including representatives of the troglobionts Diplopoda, Arachnida, Coleoptera and Crustacea: Copepoda, Isopoda and Amphipoda. The artificial galleries can be important for the reproduction of Rhinolophus species as well as Miniopterus schreibersii, Myotis capaccinii, M. myotis, etc. From the end of August to the beginning of October many galleries, particularly the ones in areas without caves, can serve for the autumn concentration of hundreds of bats for reproduction and social contacts. The habitat is a preferred winter roost for the non-migrating bat species like Rhinolophus ferrumequinum, Rh. hipposideros, Barbastella barbastellus, Plecotus spp., etc.
Characteristic taxa.
- Animals: Diplopoda – Glomeris spp., Balkanopetalum spp., Brachydesmus spp., Polydesmus spp., Typhloiulus spp.; Coleoptera – Atheta spp., Choleva spp., Duvalius spp., Pheggomisetes spp., Quedius spp., Trechus spp.; Arachnida – Meta menardi, M. merianae, Tegenaria silvestris; Diptera – Culex spp.; Trichoptera – Micropterna spp., Stenophylax spp; Lepidoptera – Autophila spp., Scoliopteryx libatrix, Triphosa spp.; Crustacea – Acanthocyclops iskrecensis, A. strimonis, Bathynellacea, Bryocamptus spp., Elaphoidella spp., Niphargus spp.; Chiroptera –Barbastella barbastellus, Myotis bechsteinii, M. capaccinii, M. myotis, Plecotus spp., Rhinolophus ferrumequinum, Rh. hipposideros.
Distribution in Bulgaria. In the mountain and semi-mountain regions almost throughout the country. The artificial galleries occur mainly in Rhodopi Mts., West and Central Balkan Range, Strandzha, Rila, Vitosha Mts., etc.; from sea level up to 2000 m alt. in Rila and Ossogovo Mts..
Conservation importance. The artificial galleries serve as reproduction places and winter roosts for many bat species. Relatively rich, endemic underground water arthropod fauna has been established in such galleries in West Bulgaria. Some are the type localities (locus typicus) and also the only known localities for species new to science, e.g. in Urvich locality near Sofia for Bryocamptus aberrans and the uranium gallery in the Rilska River valley for Lombardobathynella sp.
Threats. In most cases, after the exploitation of the galleries, they are closed by detonation of their entrance. In these cases they lose their importance as a scientific locality, and stop being a bat roost. The entrances to the galleries can be destroyedby natural erosion processes in the surface soil layer. Underground caving can also close certain parts of the galleries. The development of thick tree and shrub vegetation at the entrances of the galleries can be a permanent barrier for the bats.
Conservation measures taken. The artificial galleries are not a subject of specific nature protection with the few exceptions, such as when they are habitats of species of conservation value or cultural-historical value. “Golak mine gallery” is a nature monument and protected NATURA 2000 site because it is an important shelter for bat colonies with thousands of individuals of several species. The abandoned gallery “Izdremets” is one of the most important places for the autumn gathering together and wintering of bats and is included in a NATURA 2000 site. “Katakombite” gallery near Aladzha Monastery is within the borders of Zlatni Pyasatsi Nature Park and are included in the tourist complex Aladzha Monastery.
Conservation measures needed. Inventory, description and assessment of the biodiversity of the artificial galleries in Bulgaria by regions. The most significant shelters of bats and invertebrates must be proclaimed as protected areas. Strengthening and making safe of the entrances; clearing of the vegetation near the entrances and control of the access to the important galleries. In cases of caving the entrances of the important galleries should be opened again. To include specific measures related to maintenance and protection of the artificial galleries within the borders of the nature and national parks, protected areas and NATURA 2000 sites in the management plans of the respective areas.
References. Apostolov & Pesce 1991; Gueorguiev 1978, 1987; Pandourski 2000.
Authors: Ivan Pandurski, Boyan Petrov
