If you haven’t visited the Banat and Iron Gates area before, you should definitely put it on your list. A diverse, spectacular area, full of life and diversity, of dramatic beauty, out of the ordinary. With a sub-Mediterranean climate, the biodiversity on both banks of the Danube includes tens, hundreds of species of animals and plants, many of them endemic, meaning they are only found here. Bats in the Romanian-Serbian area of the Iron Gates and Banat are also of particular importance. There are a number of caves and buildings of continental importance, with colonies of hundreds and thousands of specimens of strictly protected bat species. Of the 32 species of bats with demonstrated presence in Romania, at least 29 were also identified in the Banat / Iron Gates area. And of the 31 species of bats currently identified in Serbia, at least 23 have been identified in the Đerdap / Iron Gates area, respectively in the Đerdap National Park and the Đerdap Geopark.
Moreover, between the five national and natural parks on the Romanian side of the Banat (Semenic – Caraș Gorge NP, Nera Gorge – Beușnița NP, Iron Gates NP, Domogled – Cerna Valley NP and Mehedinți Plateau GP), as well as the PN Đerdap NP in Serbia there is ongoing migration of bats. They are obviously not affected by traditional country borders, nor by the Danube. Thus, bats from the north of Serbia arrive in the caves of the Romanian Banat for the winter period, for hibernation, and migrate back to Serbia to form nursery colonies during the summer period. This migration was demonstrated by sightings in Romania of bats with Serbian rings, from as early as 2014.
Given that bats disregard traditional borders, it becomes clear that the conservation of these colonies of continental importance in the area of the Romanian-Serbian Banat must, likewise, ignore these borders, and be based on common principles. A hibernation colony in Romania does not benefit from adequate protection, if the nursery colony in Serbia, from where bats are migrating, is not protected. And vice versa: the nursery colonies of Serbia are threatened, if the specimens from the Romanian hibernation colonies are subject to disturbance. The project Transboundary conservation of horseshoe bats in the Romanian-Serbian Iron Gates, implemented in 2020-2023, and financed by the Conservation Leadership Programe, aims to achieve this cross-border conservation.
The Romanian-Serbian Banat region is remarkable as a whole, but the same can be said about each national and natural park in the area. Thus, below we present to you the most remarkable details about the bats of these parks.
Discover the bats of the Iron Gates with a single click on the map below:
Bats of the Iron Gates Nature Park (Romania)
Of all the protected areas of the Romanian Banat, the Iron Gates Nature Park is the most closely linked to the course of the Danube. Already from Baziaș, where the Danube becomes the border between Romania and Serbia, up to Drobeta-Turnu Severin, the natural park follows the course of the Danube for over 130 km, thus being one of the largest protected areas in Romania. And at the same time, one of the most spectacular and (bio)diverse areas of the country.
The nature park offers the full range of roosts and habitats for bats. Here we find caves with spacious or hard-to-reach halls, touristic caves visited annually by thousands of tourists, abandoned mining areas (with mine galleries and buildings suitable for bats), old-growth deciduous forests, mixed forests and meadow areas. The islands on the Danube themselves are ideal for bats, for example Ostrov Island at Moldova Nouă, Calinovăt Island towards Baziaș, or Simian Island downstream of Drobeta-Turnu Severin. In the wetland areas of the park, for example in Nera Delta or on the inner lakes of ostrov Island, but also on the banks of the Danube, you can observe the frantic flight of bats, hunting and eating insects by the thousands during the nights of warm seasons.
Based on the bat research of the last 10 years, including those within the current project and the Dare2Connect international project, we can say that the Iron Gates Nature Park has one of the most diverse bat faunas in Romania, with at least 23 bat species identified so far (out of Romania’s 32). We find here all types of colonies: large hibernation colonies during the winter, nursery colonies with thousands of bats during the summer, but also transitory / migration colonies during the spring and autumn periods. But the diversity of the Iron Gates is demonstrated not only by the simple number of bat species, but also by the presence of species typical for well-defined habitats.
Thus, we know colonies of exclusively cave-dwelling species (= they form colonies only in the underground), for example the bent-winged bat (Miniopterus schreibersii), the long-fingered bat (Myotis capaccinii) or Blasius’s horseshoe bat (Rhinolophus blasii). The barbastelle (Barbastella barbastellus) and Geoffroy’s bat (Myotis emarginatus) are species that prefer to hunt in hardwood, old-growth forests of high natural value. And thanks to the presence of the Danube, lakes and wetlands, all three bat species associated with water habitats are present in the park: the pond bat (Myotis dasycneme), Daubenton’s bat (Myotis daubentonii) and the long-fingered bat (Myotis capaccinii). Some of the largest colonies of the Noctule (Nyctalus noctula) and the Pipistrelle (Pipistrellus pipistrellus) of Romania hibernate in the Gura Ponicovei cave, the latter being a colony of over 4,000 bats.
But even the settlements inside the park offer good conditions for bats. At the moment at least 4 buildings in the area (including 2 abandoned buildings) offer home to maternity colonies during the summer. The attic of the Serbian-Orthodox Church in Divici is home to a colony of 400-500 speciments of the greater mouse-eared bat (Myotis myotis) and of the lesser mouse-eared bat (Myotis blythii). The Catholic Church in Eibenthal houses a small colony (20-25 individuals) of the brown long-eared bat (Plecotus auritus).
From the point of view of cross-border migration between Serbia and Romania, we already know 2 locations inside the Iron Gates Nature Park, where we observed specimens with Serbian rings. These specimens have been observed in all seasons of the bat lifecycle: during the winter / hibernation, during summer / nursery, and also during the migration periods of spring and autumn. Thus, the area of the Iron Gates Nature Park becomes important not only from the point of view of resident bat populations, but also for bats migrating from Serbia.
Based on the observed diversity, the presence of colonies with thousands of bats, as well as that of the specimens of ringed bats from Serbia, we can say without a doubt that the Iron Gates have a continental importance from the point of view of bats, and the conservation of roosts (caves, mine galleries, buildings) and habitats (forests, water bodies, pastures, meadows) is essential.
With the exception of Veterani Cave, which is a touristic cave, the other caves of the Iron Gates Natural Park are accessible based on SHC authorization and on park approval. For the protection of bat colonies in the park, it is recommended to avoid caves with hibernation colonies during the winter (December – March), as well as caves with maternity colonies during the summer (June – July). Similarly, for the protection of bat colonies in buildings, it is recommended to renovate them only outside the May-August period, with the preservation of existing elements (access roads, windows, etc.).
Bats of the Đerdap Geopark (Serbia)
There is not a single person, who, once driving along the Đerdap route did not think, even for a moment, that he had teleported somewhere on the sea-side. Đerdap Gorge, or Iron Gates, with a length of over 100 km, is the longest river-breached gorge in Europe. The Danube has even one place so narrow that there is only 150 meters between Romania and Serbia. And yet, in other places it is so wide, that one can think this is somewhere as the sea. In some parts of the gorge there are also giant “holes” with a depth of 80+ meters, being among the deepest river sections on the planet.
Because the Danube in the Iron Gates is so impressive, in 1974 the surroundings, from Golubac to Karataš, was designated a national park, the largest in Serbia: the Đerdap National Park. In addition, in July 2020 the Đerdap Geopark was declared, joining the UNESCO global network of geoparks. The geopark completely encompasses the area of the national park and extends it for another 692 km2. The specific geomorphology, the favorable climate moderated by the large mass of the Danube, and the complex network of gorges, canyons and deep bays generated an area that is kind of a reserve of tertiary flora, vegetation and fauna.
Đerdap Visitor Centre
Over 1.100 plant species and subspecies live in the national park area, as well as a great variety of animal species. The Đerdap area is abundant in well-preserved habitats, like forests and wetlands, pastures, cliffs and rocks. These provide favorable conditions for bat habitats, as well as a large number of suitable roosts for their colonies: karstic and other underground structures, hollow trees, and various human buildings.
The first records of bats from Đerdap is from 1946, in the old town near Golubac fortress, followed by research in 1965-1970, before the construction of the Iron Gates dam and the submergence of Đerdap Lake. After that, sporadic research was carried out in 1996 and 2005, followed by a systematic inventory in Đerdap National Park, involving 48 caves, several mines and one building.
To date, out of the 31 bat species of Serbia, 23 were confirmed on the area of the national park. During the fieldwork of the CLP project in 2020-2022 we checked several underground locations in the area, and confirmed the presence of maternity colonies, as well as transitory and hibernation colonies of several bat species. Many of the locations were surveyed for the first time.
During the project, we have identified several caves of high importance for the conservation of Đerdap bat populations. One such cave is Gradašnica Cave, which is home to maternity colonies of Rhinolophus ferrumequinum, Rhinolophus euryale, Myotis capaccinii and Miniopterus schreibersii. But it is also a hibernation roost for Rhinolophus euryale, Rhinolophus hipposideros and Nyctalus noctula. In addition, at least four caves proved also to be important roosts for hibernation for Rhinolophus ferrumequinum (50-500 bats), Rhinolophus euryale (with the largest hibernation colony in the Đerdap area, with ca. 1600 bats), Miniopterus schreibersii (ca. 500 bats), and Rhinolophus hipposideros (50-60 bats). One location turned out to be important during spring migration of Rhinolophus euryale (about 300 bats).
Large maternity colonies are also formed during the summer in at least three caves of the Đerdap National Park. One site is home to ca. 3000 Miniopterus schreibersii, while another includes a nursery of three species (Myotis myotis, Myotis blythii, Miniopterus schreibersii) of around 3.000 bats. A third one is home to around 2000 medium-sized Rhinolophus and around 700 Rhinolophus ferrumequinum. Lastly, at least two caves proved to be extremely important during Autumn migration, with swarming (=bat mating) happening there for species like Rhinolophus ferrumequinum, Eptesicus serotinus, Myotis bechsteinii, Myotis alcathoe, Myotis myotis and Miniopterus schreibersii.
Thanks to the ringing of bats in Serbia, and their subsequent sightings, it was confirmed that several species cross into Romania and back relatively often. An increasing number of bats with Serbian rings (for example Rhinolophus ferrumequinum, Myotis myotis, Myotis blythii, and Miniopterus schreibersii) are found in various caves of the Romanian Banat region. These are either hibernation sites (for winter), or locations used by transitory / migrating colonies during spring and autumn. Thus it is clear that traditional state borders do not mean anything to highly mobile, flying organisms like bats. And therefore it becomes increasingly important to establish cross-border conservation efforts, that encompass the entire migratory range of these species and colonies.
For accessing the caves of the area, contact the Đerdap National Park or the Touristic Organization of Majdanpek. The above text cites details from the following works:
- Budinski I., Pejić B., Bogosavljević J. (2021): Zimski monitoring slepih miševa na području NP Đerdap. Bat winter monitoring at the territory of Đerdap National Park in 2021. Drugi susreti ljubitelja šišmiša, 23.april 2021. Sarajevo, Bosna i Hercegovina. Knjiga sažetaka pp. 52‒
- Ćalić J. (2015): Speleološki objekti nacionalnog parka Đerdap. JP Nacionalni park Đerdap, Donji Milanovac. 200 pp.
- Grubač B., Milovanović Z. (2012): Slepi miševi Đerdapa. JP Nacionalni park Đerdap, Zavod za zaštitu prirode Srbije, Veterinarski specijalistički institut Kraljevo. Donji Milanovac – Beograd. 113 pp.
- Mirić Đ. (1981): Sastav teriofaune Đerdapa pre stvaranja akumulacionog jezera. Biosistematika 7(1): 81‒94.
- Paunović M. (2018): Slepi miševi. U: Stanković D., M. Paunović, M. Raković (ur.) Atlas migratornih ptica i slepih miševa Srbije. Ministarstvo zaštite životne sredine Republike Srbije, Ministarstvo kulture i informisanja Republike Srbije, Prirodnjački muzej u Beogradu. Posebna izdanja 46: 457‒
- Paunović M., Karapandža B., Budinski I., Stamenković S. (2020): Fauna slepih miševa (Mammalia: Chiroptera) Srbije. Srpska akademija nauka i umetnosti, posebna izdanja. Beograd. Posebna izdanja DCKSCIII, Odeljenje za hemijske i biološke nauke Knjiga 13, 601 pp.
- Pejić B, Bogosavljević J. (2022): Istraživanje slepih miševa nacionalnog parka Đerdap (Srbija), jesen 2021/Bat survey in Djerdap National Park (Serbia), autumn 2021. Hypsugo Glasnik za istraživanje šišmiša Balkana/Journal of Bat Research in the Balkans 6(2): 19-29 pp. Petrov B.M., Lindtener V. (1946): Golubac. Ekskurzija br. od2-VII. do 4.VII.1946g. Beleška sa terena, Arhiva Prirodnjačkog muzeja u Beogradu.
Bats of the Nera Gorge – Beușnița National Park (Romania)
Known for its spectacular waterfalls such as Beușnița, Cârșa or Șușara, as well as spectacular karst formations such as Dracului Lake or Ochiul Beiului, the national park is crossed by the Nera river, forming the longest gorges in Romania, with around 25 km lenght. The karst landscape is complemented by steep rocky areas, meadows and pastures, as well as virgin forests. Based on this latter aspect, virgin forests, the park stands out through the inclusion of an area of over 4.000 hectares in the world heritage UNESCO sites of ancient and primeval beech forests of the Carpathians and Europe. The outstanding natural value of the national park also comes from the difficult access to certain areas, which on the one hand allows the existence of an environment without significant disturbance for bats (in caves that are difficult or not at all accessible), on the other hand indicates a high potential for the existence of large bat colonies, still undiscovered.
In the last 10 years, including within the current project and voluntary monitoring activities of CBRC, at least 19 bat species have been identified within the park, among them both strictly cave-dwelling species (forming colonies only in underground) and typical woodland species. But these data come from only a fraction of the park, so we are convinced that the bat population of the park is composed of many more species. Dozens of underground locations are still unverified. The largest known colony in the park area counts over 1,700 specimens of at least 8 species during hibernation, being the Păuleasca Pothole.
Significant colonies are also located on the edge of the national park, for example in abandoned buildings or mine galleries. Specimens from these colonies certainly feed in habitats within the national park. In one of the cases it is one of the largest and most diverse maternity colonies in Romania, located in an abandoned building, with over 700 specimens of the greater horseshoe bat (Rhinolophus ferrumequinum), the Mediterranean horseshoe bat (Rhinolophus euryale) and Geoffroy’s bat (Myotis emarginatus).
At least three underground sites within and on the park’s borders can be considered to be of continental importance due to the presence of thousands of greater mouse-eared bats (Myotis myotis), lesser mouse-eared bats (Myotis blythii) and over 500 greater horseshoe bats (Rhinolophus ferrumequinum). Several specimens belonging to the latter species, bearing rings from Serbia, were identified in two underground locations of the park and in one abandoned building. The underground locations are hibernation colonies, but the ringed specimens in the building were part of a nursery colony. Thus, as in the case of the locations in the Iron Gates Nature Park, bats from Serbia arrive in the area to hibernate in the park’s undisturbed caves, but apparently also to form nursery colonies.
The caves of Nera Gorge – Beușnița National Park are accessible based on SHC authorization and park approval. For the protection of bat colonies in the park, it is recommended to avoid caves with hibernation colonies during the winter (December – March), as well as caves with nursery colonies during the summer (June – July). Similarly, for the protection of bat colonies in buildings, it is recommended to renovate them only outside the May-August period, with the preservation of existing elements (access roads, windows, etc.).
Bats of the Semenic – Caraș Gorge National Park (Romania)
The park area includes several nature reserves of special importance. One extraordinary example is the Izvoarele Nerei Forest, which covers over 5.000 ha, with beech trees over 350-400 years old, and is among the largest virgin forests of Europe. The Izvoarele Nerei Forest is included in the UNESCO World Heritage list of virgin beech forests of the Carpathians and Europe. The Cheile Carașului Reserve is equally impressive, for both its 19 km length, and the large number of caves, easily over 500. The Comarnic and Buhui Cave Reserves, or the Gârliștei Gorges are just some of the natural attractions of the park.
In this diversity of natural habitats offered by the area, it is not surprising that the current project, as well as other CBRC projects, have demonstrated the presence of at least 22 species of bats out of 32 in Romania. However, we certainly do not know all of the park’s bat species, or the colonies in the dozens, perhaps hundreds of unverified caves. What is certain: the park’s caves are home to the largest colonies for some Romanian bats species, and are thus of continental importance.
Buhui Cave, besides being an ideal roost for colonies of no less than seven bat species, among them is the largest colony in Romania of the greater horseshoe bat (Rhinolophus ferrumequinum) with over 1,700 individuals. With so many individuals, the colony of this species in Buhui Cave is also one of the largest in Europe. Here we also find the largest hibernating population of the Barbastelle (Barbastella barbastellus) in Romania, with 400-500 individuals. This species is typical for old growth, valuable forests, using natural hollows most of the year, and resorting to caves only when temperatures are too low. However, Buhui Cave is also home to nationally important colonies of the long-fingered bat (Myotis capaccinii), greater mouse-eared bat (Myotis myotis), lesser mouse-eared bat (Myotis blythii) and bent-winged bat (Miniopterus schreibersii). Overall, Buhui Cave is a site of continental importance for bat conservation.
Similarly, Comarnic Cave includes one of the largest colonies of the greater horseshoe bat (Rhinolophus ferrumequinum) in Romania, with over 1,200 individuals, the second largest colony after that of Buhui Cave. It is thus remarkable that a single national park includes the first two colonies in terms of size, of the species in Romania. Although at the moment only one nursery colony is known in the park’s area (in the Gârliștei Gorge), there are certainly many more such sites among the hundreds of caves of the park, that are home to this vital element in the life cycle of bats: colonies of females and pups.
During the current project we observed bats with Serbian rings in four caves of the park area. Most individuals, more than 10, were observed in Buhui Cave. The whole area of the national park is a major hibernation site for bats from Serbia, and at the same time is currently the northernmost area of the Banat region where we know of bats coming from Serbia. At the same time, the extensive forests provide ideal habitats for species closely related to this type of habitat. Conservation of the entire habitat network (forests, caves, lakes, rivers, etc.) is essential, if these continentally important bat populations are to persist in the park’s area.
The caves of Semenic – Carașului Gorge National Park are accessible based on SHC authorization and park approval. For the protection of bat colonies in the park, it is recommended to avoid caves with hibernation colonies during the winter (December – March), as well as caves with nursery colonies during the summer (June – July). Similarly, for the protection of bat colonies in buildings, it is recommended to renovate them only outside the May-August period, with the preservation of existing elements (access roads, windows, etc.).
Bats of the Domogled – Cerna Valley National Park (Romania)
With over 60.000 hectares, the Domogled – Cerna Valley National Park is the largest national park in Romania. The area is notable for its combination of sub-Mediterranean climate with alpine meadows, karst areas, thermal springs and extensive forests, resulting in an extraordinary diversity of habitats and species. Among the more than 1.100 plant species in the area are dozens of endemic species, as well as animal species. More than 75% of the park’s area is covered by deciduous forests, including three areas with a total surface of more than 9.000 hectares that are included in the UNESCO World Heritage List of virgin beech forests of the Carpathians and Europe.
Besides the high diversity of habitats and species, the Domogled – Cerna Valley National Park is also the area with the highest known diversity of bat species in Banat and the Iron Gates. At least 25 bat species out of 32 in Romania have been identified during this and other CBRC projects in the past. The park area is also the only one in Romania with a demonstrated presence of all five species of horseshoe bats (Rhinolophus).
A number of caves provide ideal roost for colonies of European and national importance. Right in the parking lot of the Roman Hotel is the Despicătură Cave, home to the only known nursery colony of the lesser horseshoe Bat (Rhinolophus hipposideros) in the Porțile de Fier / Banat area. The cave’s gate has been changed to a new one as part of the current project for the protection of the nursery of females and pups. The Pecenișca Cave and the Adam Pothole, besides hosting colonies of hundreds of individuals, are also the only two sites in Romania with confirmed presence of all five species of horseshoe bats (Rhinolophus) in Europe.
The largest currently known hibernating population in Domogled – Cerna Valley National Park is the Șălitrari cave, with over 7,000 individuals, being of continental importance. Here we find a huge colony of the Pipistrelle (Pipistrellus pipistrellus) of more than 4,000 individuals, as well as a colony of more than 1,700 individuals of medium-sized horseshoe bats (Rhinolophus euryale and Rhinolophus blasii). Our access to the Șălitrari was greatly aided by the Prusik Caver Club of Timișoara, to whom we would like to thank this way. The colony of medium-sized horseshoe bats (Rhinolophus euryale and Rhinolophus blasii) in Cloșani Cave has decreased in recent years from 1.500 to only 250-300 individuals, which indicates the need for conservation measures in this strictly protected cave.
During the project we did not find any ringed bats from Serbia in the colonies in the park, but due to the multitude of caves (more than 800), the distance bats can migrate (tens, sometimes hundreds of kilometers), and the proximity of Serbian caves (only 20-40 km away), we cannot exclude their presence. However, even with current conditions, the colonies in the park are of continental and national importance, and sustainable conservation efforts are needed both for roosts (caves, buildings, hollow trees) and for maintaining foraging habitats (deciduous forests, meadows, etc.).
The caves of Domogled – Cerna Valley National Park are accessible based on SHC authorization and park approval. For the protection of bat colonies in the park, it is recommended to avoid caves with hibernation colonies during the winter (December – March), as well as caves with nursery colonies during the summer (June – July). Similarly, for the protection of bat colonies in buildings, it is recommended to renovate them only outside the May-August period, with the preservation of existing elements (access roads, windows, etc.).
Bats of the Mehedinți Plateau Geopark (Romania)
With an area of over 100.000 hectares, the Mehedinți Plateau is one of the largest protected areas in Romania, primarily distinguished by its karst superlatives. Complex karst systems run underground, forming impressive caves, such as Topolnița or Bulba Caves, but there are also surface karst formations, such as Podul lui Dumnezeu (God’s Bridge) or Coșuștei Gorge.
Based on data from the current and past CBRC projects, at least 19 bat species are present in the area of the Mehedinți Plateau Geopark. A karst superlative in itself, Topolnița Cave is home to colonies during both the hibernation and the nursery season. One of the largest colonies of medium-sized horseshoe bats (Rhinolophus euryale and Rhinolophus blasii) in Europe is at home in this cave, numbering over 8.000 during the winter season. Part of this colony migrates to other caves for the warm seasons, but about 4.000 females remain in Topolnița Cave, to give birth to the next generation.
Epuran Cave, Izverna Cave and Podul Natural Cave are ideal places for hibernation colonies. Epuran Cave, besides being an exceptionally beautiful cave, is home to one of the largest hibernating populations of the lesser horseshoe bat (Rhinolophus hipposideros), of about 200 individuals. Izverna Cave is used in winter by about 100 individuals of the great horseshoe bat (Rhinolophus ferrumequinum). A colony of this species hibernates behind the lake of Podul Natural Cave, with more than 250 specimens.
Due to the diversity of habitats and climate, the Geopark’s caves are also ideal roosts for nursery colonies of the greater mouse-eared bat (Myotis myotis), lesser mouse-eared bat (Myotis blythii), long-fingered bat (Myotis capaccinii) and bent-winged bat (Miniopterus schreibersii). Both the Bulba Cave and the Mare at Balta Cave include such colonies, with over 1.000 individuals each.
In the current project we did not find any ringed bats from Serbia in the Geopark colonies, but due to the multitude of caves (over 100), the distance bats can migrate (tens, sometimes hundreds of kilometers), and the proximity of Serbian caves (only 20-30 km away), we cannot exclude their presence. However, even with the current conditions, colonies in the Geopark are of continental and national importance, and sustainable conservation efforts are needed both for roosts (caves, buildings, hollows) and for maintaining foraging habitats (deciduous forests, meadows, etc.). Being a vast area, with many caves still unexplored from the bats’ point of view, other species and colonies not yet discovered in the Mehedinți Plateau Geopark are certainly present.
The caves of Mehedinți Plateau Geopark are accessible based on SHC authorization and geoark approval. For the protection of bat colonies in the park, it is recommended to avoid caves with hibernation colonies during the winter (December – March), as well as caves with nursery colonies during the summer (June – July). Similarly, for the protection of bat colonies in buildings, it is recommended to renovate them only outside the May-August period, with the preservation of existing elements (access roads, windows, etc.).
In the period of 2020-2023, CBRC, in partnership with the Myotis Group for Bat Conservation and fellow researchers of the Museum of Natural History in Belgrade (Serbia), implements the project Transboundary conservation of horseshoe bats in the Romanian-Serbian Iron Gates. Funded by the Conservation Leadership Program (total budget: $30,824), the project aims to improve the conservation status of horseshoe bats in this region through (1) accurate scientific data on bat migration in the region, (2) concrete actions of conservation at the most important bat locations and (3) an engaged and well-informed public on both sides of the Danube.
