Application of GIS modelling to quantify fish habitats in lakes

Abstract

AbstractQuantitative measures of fish habitat in lakes and impoundments have seldom been proposed. The availability of Geographic Information Systems (GIS), however, now provides a means for researchers to assess fish habitat on a whole‐lake scale. GIS modelling was used in this study to quantify the impacts of stratification on the amount and distribution of brown trout (Salmo trutta) habitat in a large reservoir in Victoria, Australia. Species‐specific temperature and dissolved oxygen tolerance ranges for brown trout were applied to the hydrological profile and lake bathymetry. The model predicted that brown trout habitat was reduced by 82% in the summer, and the model was validated with position data from acoustically tagged adult brown trout. This study demonstrated that a quantifiable assessment of fish habitat on a whole‐lake spatial scale can be made. It also could be applied to a range of fish species, with applications in ecosystem monitoring and fisheries management.