Somogyi Múzeumok Közleményei 14. (2000)

Lanszki J. – Körmendi S. 2000: Ragadozó emlős közösség táplálékösszetétele a Boronka-melléki Tájvédelmi Körzetben, Somogy megyében

Diet of a Carnivora community in the Boronka Nature Conservation Area, in Somogy County JÓZSEF LANSZKI - SÁNDOR KÖRMENDI LANSZKI J. - KÖRMENDI S.: Diet of a Carnivora community was studied by scat analysis in the Boronka Nature Conservation Area (Somogy County, southern Hungary). Abstract: The numbers of samples elaborated were 335 for red fox (Vulpes vulpes L), 130 for pine marten (Martes martes L), 90 for badger (Mêles mêles L.) and 1280 for otter (Lutra lutra L). The numbers of species or distinguishable taxons eaten by the predators were 23 vertebrates, 15 invertebrates and 13 plants by red fox, 16 vertebrates, 19 invertebrates and 10 plants by pine marten, 11 vertebrates, 22 invertebrates and 7 plants by badger and 17 vertebrates, 10 invertebrates and 4 plants by otter. Small mammals were dominant in the food of red foxes in winter, spring and autumn (57, 37 and 38%, resp.). Invertebrates (42%) and plants (28%) represented the biggest ratios in summer. Small mammals in winter (55%) and in autumn (40%), small mammals (30%) and invertebrates (29%) in spring and invertebrates (42%) in summer were the most common food of martens. Corn grains (52%) originating from wild boar feeders and invertebrates (23%) were the dominant food components of badgers in winter, while insects (73%) and ringworms (68%) dominated in spring, summer and autumn. The dominant food of otters was fish (67 to 91%), irrespective of season or period of time. Introduction Scat analysis is a widely used method for studying the feeding ecological characteristics of carnivorous species. Qualitative evaluation performed on the basis of scat analysis provides a fairly true picture of the types of prey animals and plants eaten and of the frequency of occurrence of these. In the relevant literature on feeding ecology the description of food composition is very often restricted to the larger taxonomic units. If detailed lists are published, these usually refer to some important food categories only (e.g. CIAMPALINI and LOVARI 1985, GOSZCZYNSKI 1986, JEDRZEJEWSKl etal. 1989, SERAFINI and LOVARI 1993, LANSZKI and KÖRMENDI 1996a). There are some examples of detailed food composition lists from the Mediterranean (PAPAGEORGIOU et al. 1988), western European area (DEBROT et al. 1984), central European area (SUCHENTRUNK 1984, KOZENA 1988, ZALEWSKI et al 1995) and northern European area (ENGLUND 1965, ERLINGE 1967, JENSEN and SEQUIRA 1978) and Scotland (KOLB and HEWSON 1979, KRUUK 1989, 1995). There is a serious shortage of information in the literature on this subject for Hungary. Only the food composition of the fair red fox (ERDEI 1977, FARKAS 1983) and of the strictly protected otter (KEMENESNÉ and NECHAY 1990, LANSZKI and KÖRMENDI 1996b) has been studied so far. In this paper the diet of a Carnivora community was studied in a nature conservation area including ponds and forest habitats. The species studied were red fox, marten, badger and otter. Our objective was to analyse the seasonal food composition of these species qualitatively and to draw up and publish detailed lists of their food composition. Study area and methods The investigations were carried out in the Boronka Nature Conservation Area (10 x 10 km UTM code: YM04). Its streams belong to the water catchment area of Lake Balaton. In the Dávod area there are six fish ponds that were established by erecting dams in the valleys on a (Dryopteridi-Alnetum) vegetation area at the end of the 19th century. These ponds are 100 cm deep on average, their total surface 83 ha. Over one quarter (approx. 25 ha) of the surface is covered with reeds (Scirpo-Phragmitetum). The system of fish farming can be regarded as extensive in the nature conservation area. The ponds are surrounded by Calamagrosti-Salicetum cenereae and DryopteridiAlnetum and by extended Fraxino pannonicaeCarpinetum habitats. The food composition of the predators was investigated by scat analysis. The scats were collected every two weeks on a standard route (approx. 5000 m long). The sample collection spots were divided between dams of the ponds (80 %) and forest pathways (20 %), these being the main routes of movement of carnivores. The numbers of scats evaluated during the two years of investigations were: red fox (Vulpes vulpes L.) 335, pine marten (Martes martes L.) 130, badger (Mêles mêles L.) 90 and otter (Lutra lutra L.) 1280. Prey determination was performed by microscope on the basis of indigestible remains such as hair and dentition (TEERINK 1991, DEBROT et al. 1982, ÚJHELYI 1986), feather (BROWN et al. 1993), scales, pharyngeal teeth and bones (BERINKEY 1966, PAUNOVIC 1990, PINTÉR 1992) and scutellum and calciferous skeleton (MÓCZÁR 1969). Reference collections were also beneficial in the identification of fish and plant species. To survey the dominant food supply of ground predators the authors applied traps for catching small mammals live in the Dávod area on a monthly basis between April and November 1998. The species caught by the traps were common shrew (Sorex araneus), fat dormouse (Glis glis), common dormouse (Muscardinus avellanarius), common field mouse (Apodemus sylvati-