Seminar paper from the year 2018 in the subject Geography / Earth Science - Cartography, Geographic Information Science and Geodesy, grade: 2, University of Salzburg, language: English, abstract: In this paper the concept of fuzzy overlay was used to delineate suitable habitats for alpine marmots in the Dachstein region in Upper Austria. Four criteria were chosen as important factors for possible habitats for marmots: grassland as preferred type of biotope, an elevation between 800 and the foot of the glacier, the mean annual sunshine duration as well as the distance to skiing areas. By applying fuzzy membership values from 0-1 and overlaying the derived raster, a map with continuous suitability values is obtained. For decision making and finding the optimal areas defuzzification as well as a sorting out concerning the size of the areas is necessary as a final step. Fuzzy overlay analysis is an interesting approach concerning multi criteria overlay analysis. By using fuzzy sets instead of crisp boundaries, fuzzy logic allows partial membership and multiple membership. This makes it ideal to overcome uncertainties in data and in the definition of classes.