The paper deals with the problem of finding relative values for species in the case of biodiversity conservation in a cultural landscape. We use the concept of shadow prices to derive flexible functional forms that allow us to conduct an interactive and internal valuation process. The paper is organized such as that (1) the theory of shadow price derivation is presented in a framework of programming. (2) We obtain quadratic objective functions for participant in the valuation process. (3) Quasi demand and supply functions are derived from which we can simulate a market. (5) The special role of ecologists as experts and potential managers of a landscape is ad-dressed and (6), or finally, a balanced solution on values, value oriented management, and species prevalence is provided.