To transfer knowledge of risk analysis of metapopulations into praxis UFZ started a joint project with OFFIS with the objective to develop a computer tool which gives aid to decision making in nature reserve. The design of the resulting simulator, which is based on a generic metapopulation model, is oriented to support users without intense computer application or modelling knowledge. Hence, it offers a comfortable user interface and enables a very flexible method of working; its follow up version, which will be completed in autumn 1998, extends this assistance by providing a guided tour through the modelling and evaluation process. In addition to this, it will automatically document each result and consequently ensure its reproducibility. Another main emphasis in the design of the tool was laid on the feasibility of creating comparability studies by combining alternative scenarios to one experiment and offering suitable evaluation operators.