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ArchiveWenner Bálint Zsolt - year 3 Kiskunság national Park directorate, University of Veterinary Medicine Budapest, Department of Ecology Supervisors: Dr. Zoltán Korsós, Dr. Edvárd Mizsei The Hungarian Meadow Viper (Vipera ursinii rakosiensis) was once common in the grasslands of the Pannonian basin, but the agricultural use of its habitats made most of its populations disappear, now there are only a handful of isolated populations. In the last few decades the conservation of the species was up to LIFE projects, but in spite of the intensive conservation measures, its abundance did not increase measurably, possibly because of high predation pressure. The Smooth Snake (Coronella austriaca) is a widely distributed, but in some areas locally declining reptile specialist predator, that is known for its regular snake- and occasional viper predation. In one of the most important habitats of the Meadow Viper, in the Peszéradacs meadows, the Smooth Snake is abundant, so the translocation of the Smooth Snake population had been suggested. To determine the translocation’s necessity, I conducted a dietary research, the goal of which was to answer the following questions: 1) Of what taxonomic groups does the Smooth Snake’s diet consist in the study area? 2) Does the Smooth Snake prey on the Meadow Viper in the study area? 3), Is the control of the Smooth Snake population necessary for the conservation of the Meadow Viper? In addition to the dietary study, we conducted a study with the habitat choice of the Smooth Snake to answer the following question: How does prey availability effect the density of the Smooth Snake in our study area? This study was important because even though it is widely distributed and locally endangered, the small-scale habitat choice of the Smooth Snake is unknown and this type of information is crucial for later conservation programs. During the dietary research, the observed Smooth Snakes were collected, and until they defecated or for a maximum of 7 days they were kept separately, after which they were released at the sites of their capture. I examined the faeces samples and identified the remains of animals I found in them. Of the 78 individuals 58.97% defecated (n=47), the most common prey items were lizards (65.71%), followed by mammals (17.14%) and Orthopterans (11.43%). I found Coleopteran (2.86%) and Smooth Snake (2.86%) remains on one occasion each. No viper remains were found, so according to this study the Meadow Viper conservation does not require the control of the Smooth Snake population. The density of the Smooth Snake in the monitoring quadrates in relation to the density of the individual prey species and the reptiles in total, and the Shannon-diversity of the reptile community was measured using mixed linear models. Our results indicate that the Shannon-diversity (p<0.0001), the density of the Balkan Wall Lizard (p=0.033) and the Sand Lizard (p=0.0452) have a positive, while the total reptile density (p=0.0002) has a negative effect on the Smooth Snake’s density. Based on our results the Smooth Snake’s density depends on the diversity of the reptile community and on the availability of key species. List of lectures |