Search

This study was conducted on the Croatian part of the Dinara Mountain, which is part of the Dinaric Alps mountain range that extends from the Julian Alps in Slovenia to the Prokletije Mountains in Albania. The main goal of this study was to collect more data on bat species around its highest peaks. The research was part of an international inventory project „Dinara 2012“ organized by BIUS- Biology Student Association. During July 2012 more than 10 underground sites were visited in search of bat summer colonies or potential winter hibernacula locations. During August 2012 bat research was carried out mainly on roads and paths within forests, forest edges and meadows in search for potential corridors and foraging areas, or as an exit to open habitats. This study confirmed seven bat species that have already been recorded for this area (Miniopterus schreibersii, Myotis blythii, M. capaccinii, M. myotis, Rhinolophus blasii, R. euryale, R. hipposideros). Five species recorded during this survey are new records for the Dinara Mountain (M. mystacinus, M. nattereri, Nyctalus leisleri, N. noctula, P. auritus). Now, the bat list for the Dinara Mountain range is complemented and the total number of bat species is 15 (M. schreibersii, M. blythii, M. capaccinii, M. emarginatus, M. mystacinus, M. myotis, M. nattereri, Nycta-lus leisleri, N. noctula, P. nathusii P. auritus, R. blasii, R. euryale, R. ferrumequinum, R. hipposideros). Since this is a very large and complex area more extensive research of this area would provide much better information on the species present, their activity and distribution.

The cave Veternica, near the capital Zagreb, has been open for tourists since the 1960s, but bat friendly management started to develop in 2003 as a result of co-operation between the Nature Park Medvednica and the Croatian Biospeleo-logical Society. Restriction of tourist visits during bat hibernation was introduced in 2003 and a bat-friendly gate was built in 2006, with annual bat monitoring started in 2007. In the cave 18 bat species have been recorded until now. The cave is an important hibernation site for 8 bat species: Myotis bythii, M. daubentonii, M. emarginatus, M. myotis, M. nattereri, Rhinolophus hipposideros, R. euryale and R. ferrumequinum and an important summer roost for R. euryale and Miniopterus schreibersii. Winter monitoring is performed every year and includes two counts in January and February. The numbers of Lesser Horseshoe Bats in winter increased from 6 individuals in 1996 to 437 in 2013, and the trend shows significant exponential growth. This is probably related both to the restriction of touristic visits in the winter time and changes in cave gating from solid doors to horizontal bars. There are also reports from Czech Republic and Slovenia on growth in numbers of Lesser Horseshoe Bats with similar trends in some caves. Therefore we suspect that this increase in lesser horseshoe bat numbers may be a consequence of bat- friendly cave mana-gement and possibly reflect the bats‟ social learning.

Lokrum Island, Dubrovnik, Croatia, is a special reserve of forest vegetation since 1948. The total surface of the island is 0.7 km2, while dense vegetation covers 86% of the island, with the forest and maquis dominated by Quercus ilex and Fraxinus ornus. The island and the seabelt are also a Natura 2000 site. Lokrum Island, as a part of Dubrovnik Old Town, is under the protection of UNESCO as a cultural heritage. The only known data for the bat fauna on the island originate from one source stating that two bat species have nurseries in the Benedictine monastery, without any additional data on dates and numbers of specimens. In June and September 2016 we investigated the bat fauna by placing mist-nets around water bodies, searching overground and underground potential roosting sites and echolocation recording using ultrasound detectors. Overall 7 bat species were mistnetted: Hypsugo savii, Miniopterus schreibersii, Myotis nattereri, M. mystacinus, Pipistrellus kuhlii, P. nathusii and Plecotus kolombatovici. In the Benedictine monastery a nursery colony of Rhinolophus hipposideros was confirmed and one R. ferrumequinum specimen was also recorded. The nursery of Plecotus kolombatovici was also confirmed, although the exact location in the monastery complex was not found. The echolocation recordings revealed 2 more species: Tadarida teniotis and Nyctalus noctula. Preserved forest and vegetation of the island, water reservoirs at three localities, a number of overground roosts and sea caves together with the absence of visitors during the night enables a high biodiversity of bat fauna for such a small island, with 11 of the 34 Croatian- recorded bat species. The results were presented at the International Bat Night in 2016, the first ever for that particular county. Bat research results from 2016, together with additional research planned in 2017, will enable further recommendations and actions for the conservation of the bat fauna through the current development of the Lokrum Island Reserve Management Plan.

Miniopterus schreibersii is a cave-dwelling species, which is well suited for phylogeographic investigations at a large geographic scale, because of its subcos- mopolitan distribution and it consisting of lower taxa, many of which have been elevated to species level recently. In this study, 496 samples that were collected from the entire range of M. schreibersii were analyzed using nuclear microsatellite markers to investigate the taxonomy, evolutionary history and conservation of the species. In this way, the phylogeography of the species was examined in detail, across its whole global distribution area, in order to expand the existing knowledge of its phylogeographic history significantly and to provide the necessary validation of the studies that only made use of the mitochondrial markers. The examination of these nuclear loci confirmed the findings of previous studies and provided a more complete picture of the species‟ genetic distribution. Significant differentiations of the nuclear DNA were detected between 10 regions, North Africa, Lebanon, Cyprus, Anatolia, Russia, Thrace- Balkans, Slovakia, Italy, France, and Iberia, where the sample populations were located. This study also confirms the pattern of local differentiation previously detected in mitochondrial DNA.

Miniopterus schreibersii is a cave-dwelling species, which is well suited for phylogeographic investigations at a large geographic scale, because of its subcosmopolitan distribution and it consisting of lower taxa, many of which have been elevated to species level recently. In this study, 496 samples that were collected from the entire range of M. schreibersii were analyzed using nuclear microsatellite markers to investigate the taxonomy, evolutionary history and conservation of the species. In this way, the phylogeography of the species was examined in detail, across its whole global distribution area, in order to expand the existing knowledge of its phylogeographic history significantly and to provide the necessary validation of the studies that only made use of the mitochondrial markers. The examination of these nuclear loci confirmed the findings of previous studies and provided a more complete picture of the species‟ genetic distribution. Significant differentiations of the nuclear DNA were detected between 10 regions, North Africa, Lebanon, Cyprus, Anatolia, Russia, Thrace- Balkans, Slovakia, Italy, France, and Iberia, where the sample populations were located. This study also confirms the pattern of local differentiation previously detected in mitochondrial DNA.

Krk Island is located in the northern Adriatic Sea and is fairly close to the Croatian mainland with which it is connected since 1980 by a 1, 430 metre long bridge. During past research 11 bat species were recorded on the island of Krk: Miniopterus schreibersii, Myotis blythii, M. capaccinii, M. emarginatus, Nyctalus noctula, Pipistrellus pipistrellus, P. kuhlii, Rhinolophus blasii, R. euryale, R. ferrumequinum and R. hipposideros. In July 2012 a bat inventory of the Njivice lake area was conducted using mist netting, echolocation recording and roost search. The only mist netted species was a juvenile female Myotis daubentonii which has been recorded in the vicinity in the nearby area of the town of Rijeka on the Croatian mainland (dana older than 50 years). Myotis capaccinii was recorded on the island of Krk for the first time in the autumn migration during 2007 in the area of the Vrbničko polje tunnels, and we also confirmed the species in July 2012. Lake Njivice is exceptionally rich in biodiversity. It is one of the 2 major water reservoirs on the island and is surrounded by a highly structured mosaic of habitats: dense stands of shrubs, woodland, wet and dry grassland and pastures. Various types of woodland habitat (oak, old willow forests, hornbeam) may support roosting demands of M. daubentonii whereas M. capaccinii depends on underground roosts. Two large freshwater bodies (Lake Njivice and Ponikve) approximately 10 km apart, support the hunting habitat of both species. The findings of M. daubentonii and M. capaccinii are around 10 km apart and there is still more research needed to confirm species overlap on the island. The island of Krk is the only island in Croatia with confirmed recording of M. daubentonii.

Miniopterus schreibersii and Rhinolophus euryale are considered as priority species for autecological studies according to UNEP/Eurobats. In Croatia all bat species are legally protected. In the Croatian Red List (2004) M. schreibersii is in the EN category and R. euryale in the VU category. Research on both species started in 2003 in the Veternica Cave near the town of Zagreb, the capital of Croatia. The nursery of both species with ca 500 individuals uses the unprotected, warmest part of the cave. Although the cave is under the authority of Medvednica Nature Park, the bats are often disturbed since it is very close to the capital and guided tour is encouraged. The path leading to one of the popular tourist spots passes by the cave and bats may easily be disturbed. A data logger measuring the temperature and relative humidity every 5 minutes is located in the part used by bats. The bats usually start to use the cave in June and depending on the weather they may stay there until late October. In the year 2003 no young were recorded in the cave, but there were young in the following year. Possible reasons for this may include extensive disturbance by visitors. In this work we present data on current status of both species in Croatia, microclimate measurements, wing design of traced individuals and a proposal for using grills that would restrict disturbance of bats by visitors for the protection of that part of the cave.

The Veternica Cave is open for visitors and run by the Medvednica Nature Park. It is located near Zagreb, the capital of Croatia, and is one of the key bat spots for the northwestern part of Croatia. The total length of the cave passages is nearly 7, 000 m with very different microclimate conditions. The first 400 m are accessible for tourists and are under the influence of external climate. There have been 14 bat species recorded until now. Rhinolophus ferrumequinum and Rh. euryale form winter colonies and Rh. euryale and Miniopterus schreibersii use the cave as summer roost. Myotis daubentonii, M. nattereri, M. emarginatus, M. myotis, M. blythii and Rh. hipposideros are found in crevices or on cave walls throughout the winter mainly as solitary individuals in colder parts of the cave. During very cold weather the cave provides a valuable shelter for M. bechsteinii, Eptesicus serotinus, Barbastella barbastellus and Plecotus spp. In the winter of 2004, Plecotus macrobullaris was recorded in the cave and that part of Croatia in general, for the first time. Data loggers measuring temperature and humidity at 5 minute intervals are set at 5 sites on the cave walls. Temperature, humidity and wind speed were measured near individual bats. Data on microclimate preferences of different bat species are discussed and compared with data from research conducted in winter of 1995/1996. A significant decrease in the number of R. ferrumequinum and R. euryale has been noted and recommendations for bat conservation through sustainable cave management are offered.