"MOFIR: Development of a fish habitat model for German Waterways"The modular modelling platform INFORM (Integrated Floodplain Response Model) developed at the German Federal Institute of Hydrology was created to predict and assess the ecological impacts of structural measures and the changing uses of German Waterways. In addition to existing modules representing the ecological interactions in floodplain areas, the development of the fish habitat module MOFIR (Model for Fish Response) further extends the application area of INFORM to aquatic habitats.
Fundamental to the MOFIR modelling approach is the use of a minimal number of key parameters based on existing data, making additional field data collection unnecessary. The required hydraulic parameters can be taken from the implemented hydraulic model in INFORM. Supplementary parameters relevant to fish have also been included to describe the characteristic features of waterways (e.g. groynes) and are incorporated through analyses of aerial photographs.
The MOFIR module is divided in two main components. MOFIR 1 can be applied for rapid preliminary planning and is based on simple rules utilizing classified model parameters to calculate habitat suitability for different ecological groups. MOFIR 2 is developed for detailed concept planning by adapting the established fuzzy-logic approach used by the habitat model CASiMiR to waterways. MOFIR 2 enables fish habitat modelling of various fish species and life-stages. The impacts of planning scenarios on fish habitats can be compared using an evaluation tool internal to the INFORM modelling platform.The article presents the key issues which are to be considered when modelling fish habitats of waterways and their implementation into MOFIR.