Marián Miklós: A Bakony természettudományi kutatásának eredményei 20. - A Bakony hegység kétéltű- és hüllőfaunája (Zirc, 1988)

The amphibian and reptile fauna of the Bakony mountains (Amphibia, Reptilia). A herpetological survey (Summary)

THE AMPHIBIAN AND REPTILE FAUNA OF THE BAKONY MOUNTAINS (AMPHIBIA, REPTILIA). A HERPETOLOGICAL SURVEY This paper presents the results of a 25-year herpetological study conducted in the frame of the "Natural picture of the Bakony" program organized by the Zirc Bakony Museum of Natural Sciences. The research work is based on personal field observations and collections, as well as on the herpetological collection of the Bakony Museum containing 4060 specimens, and on literary data. List of the species found is given in Tabelle 1. The Bakony, an eroded block-mountains constitutes a partregion of 4000 km of the Transdanubian Central-Range of Mountains. (Fig. 1). Phytogeografically it belongs to the "Bakonyicum floral zone" constituting the Pannonian floral region. Zoogeografically it belongs to of the Matricum "Piliscium faunal zone." The climatic conditions are heterogenous. Several types of climate vary from the mountain type of the North Bakony to the subterraneous type of the Balaton-Riviera. Distribution of the annual precipitation (600-800 mm) varies according to region. It is maximal in the North Bakony and minimal in the Balatonhighland. The mean annual temperature is maximal (10 C) in the Balaton-highland and minimal (9 C) in the North Bakony. Despite of the relatively much precipitation this region is poor in water since dolomite and limestone, main components of the mountains, absorb the water. According to excavation findings formation of the present herpetofauna of the Bakony can probably be dated from the Riss/Würm interglacial of the Pleistocene. Corinichium sphaerodactylum (Fig. 4) and Placochelys placodonta (Fig. 6) originating from the Late-Permian and Late-Trias, resp., are no of close kinship with the herptilias living presently here. But Senonemys sümegiensis (Fig. 7) can be considered as a far progenitor of the present-day Emys orbicularis. The excavations revealed some amphibian and reptile species - Bufo bufo, Pelobates fuscus, Rana dalmatina, Rana temporaria, Rana esculenta, Lacerta agilis - which occurred already here during the Pleistocene. These are still living in the Bakony, except Rana temporaria. The abundance pattern of the species is given in Fig. 8. Fauna of the part-regions can be characterized as follows: Foot of the Bakony: is a shelving, downy, wind-blown sand spotted, arid area covered by Scotch pine, Austrian-oaken-oak, occasionally by acacia, and by agrocultures. Here the flatland and hillcountry eurytopic species live, except the stenotopic Pelobates fuscus. The dominant species are Bombina bombina, Rana ridibunda and Lacerta a. agilis. Biotops of the Balaton and the Balaton-highland are located in the water-side zone of the Balaton, crowded by human settlements, in the mountainous, shrubby-barren areas of the Balaton-highland and the Keszthely mountains covered by forests and vineyards. Here, also the eury topic flatland and hillcountry species live, except the stenotopic Podarcis muralis. Occurrance of Emys orbicularis is very rare here. The character species of the Balaton-region and the Balaton-highland h Natrix t. tesselata and Podarcis m. muralis, resp. The species dominant according to abundance are Rana dalmatina, Rana ridibunda and Natrix n. natrix. The North Bakony and South Bakony constitute in close sense the Bakony mountains. Its markedly indented surface is covered by Austrian-oaken-oak, hornbeam-oak and to a less extent by pine and by extensive agricultural land. The majority of the species is eurytopic flatland and hill-country species but tehe character ones of the area - Triturus alpestris bakonyiensis, Bombina variegata, Podarcis m. muralis — are stenotopic montana species. Rana dalmatina and Lacerta a. agilis are dominant in their higher numbers. Occurrance of Pelobates fuscus in the basaltrocky environment is a special case. Emys orbicularis was observed in this part-region more than 10 years ago, but since then we have not found it again. In summary, presence of 13 amphibian species or subspecies i. e., majority of the 15 species living in Hungary, has been recorded. Of reptiles 8 species live in this area i. e., hardly more than half of the 15 native species. Role of the species in the aquatic and terrestrial ecosystems is discussed in a separate passage using a trophic approach. Necessity of protection is justified in the study by discussing the reasons responsible for the decline of the amphibian-reptile fauna of the Bakony. Finally, several recommendations and instructions - realizable in practice — are given for the environment - and nature conservation. Author's addres: Dr. MARIÁN Miklós H-6720 Szeged Kelemen u. 4. Hungary