The Ščavnica river was examined for the presence of Eurasian otter (Lutra lutra) during 6th February and 3rd May 2006. After stream regulation the otter presence has not been confirmed any more. The main question is, whether the otter is constantly present in the area or it is just an occasional visitor. Other questions are how riparian (0-5 m from the riverbed), rear (5-50 m from the riverbed) vegetation, proximity of human settlements, availability of shelters, based on the model of the Otter Haven Project (OHP),respectively, influence the otter presence. The area was searched for otter excrements (spraints) and footprints under the bridges. The number of spraints correlated with otter activity. Permanent otter presence has been confirmed, since positive signs were found on all 17 surveys. Factors affecting number of spraint are riparian vegetation and OHP-style shelters. Most spraints were found on localities with dense vegetation and in shelter areas. Vegetation and shelter areas partially overlap. There was no correlation between hinterland forest vegetation and human settlements on one side and the number of spraints on the other. Surprisingly, the majority of spraints were found along the sections with the smallest fish density, which could be explained with the dense vegetation along these sections.
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