Ábrahám Levente (szerk.): Válogatott tanulmányok III. - Natura Somogyiensis 12. (Kaposvár, 2008)

Lanszki József: A vidra elterjedése és az előfordulást befolyásoló tényezők vizsgálata a Duna alsó szakasza mentén

Study on the distribution of otters and factors influencing their occurrence on the district of lower part of Danube JÓZSEF LANSZKI The otter {Lutra lutra) is listed among strictly protected species in the EU Habitat Directive (92/43/EEC), and also in the list of species of community interest whose protection requires the designation of special areas for conservation. The otter is predominantly nocturnal, secretive animal, therefore it can be observed only occasionally in the nature. The aim of the current study was to test that protocol which was recommended by the IUCN/OSG in 2000 and complemented with Hungarian experiences, to survey otter distribution and factors influencing their occurrence. The otter survey was performed on the district of lower part of Danube, namely along the Nagykarácsonyi stream, the Szekszárdi-Séd and Szekszárd-Bátai canals (n=62 locations). Otters inhabited all studied stagnant waters while it occurred rarely in smaller streams. Occurrence (provable) of otters was ebbing statistically along narrower (especially <1 m) water courses, in shallow (<30 cm) water, at steep (>45°) bankside, with declining naturality of the bankside, at pie bridge or bridge without shoulder, increasing intensity of farming and increasing summarized human distrurbances. With similar test survey the occurrence of the otter and factors affecting that may be estimated more precisely. Results may be utilized in the otter action plan and in the habitat management plans.