Ábrahám Levente: Biomonitoring a Dráva folyó magyarországi szakasza mentén 2000-2004 - Natura Somogyiensis 7. (Kaposvár, 2005)

Ábrahám, Levente.: Biomonitoring of the butterfly fauna in the Drava region (Lepidoptera: Diurna) - Nappali lepkék biomonitoring vizsgálata a Dráva mentén (Lepidoptera: Diurna)

Natura Somogyiensis 7 63-73 Kaposvár, 2005 Biomonitoring of the butterfly fauna in the Drava region (Lepidoptera: Diurna) ÁBRAHÁM LEVENTE Somogy County Museum, Natural History Depertment, H-7400 Kaposvár Po Box 70. Hungary; e-mail: labraham@smmi.hu ÁBRAHÁM L.: Biomonitoring of the butterfly fauna in the Drava region (Lepidoptera: Diurna). Abstract: At the beginning of 2000 a biomonitoring research work started along the River Drava in Hungary. The aim of this investigation is to give information on the Hungarian biomonitoring network and up-to-date information on those environmental impacts that will also be spreading to the Drava region of Hungary, if a dam is built at Novo Virje in Croatia. A transect line estimation on the relative populations of Apatura metis, Lycaena dispar, Maculinea teleius, Maculinea nausithous, Parnassius mnemosyne, Euphydryas maturna was carried out. In this five-year period the results showed the natural fluctuation and the variability of the surveyed populations. Key words: Butterfly, Diurna, biomonitoring, River Drava Introduction The intensive research of the butterfly fauna in the Drava region started 30 years ago with the complex faunistical and environmental valuation of the Bares Juniper Woodland Landscape Protection Area. Prior to this research, only random data were available about the Drava region due to its position as a border line area of limited access. The first comprehensive faunistical study of the butterfly fauna of the region was carried out in the course of 'Mecsek and its environs' surveying program (UHERKOVICH 1978). This extremely valuable fauna revealed by the researches carried out in the Bares Juniper Woodland Landscape Protection Area played a significant role in the fact that, in 1996, the entire Drava region on the Hungarian side of the river was awarded with a national park status. By this time, the faunisical research of Lepidoptera fauna had been extended to cover the entire length of the River Drava, a 150 km long stretch from Őrtilos to Drávaszabolcs (UHERKOVICH & ÁBRAHÁM 1995). The lepidopterological researches have continued since the establishment of the national park as well, but the new aim of the research was to survey the typical habitats of the region and mainly to provide information for the mamagment plans in preparation (ÁBRAHÁM & UHERKOVICH 1998). Forming a natural borderline between the two countries, the River Drava runs between Hungary and Croatia. When the Hungarian side of the river came under protection, the idea of establishing a joint national park stretching through both side of the border was raised. But these plans have not yet been implemented as Croatia announced his intentions to build a hydroelectric power station at Novo Virje. The environmental impact caused by the power station will spread across the borders and will certainly bring significant changes to the natural assests of the region.