ImprovIng the ecologIcal valIdIty of non-market valuatIon:

This paper introduces a variant of choice experiment valuation designed to ameliorate common limitations related to a lack of ecological clarity in stated preference survey scenarios. This approach, which we call BioindicatorBased Stated Preference Valuation (BSPV), is distinguished by guidelines that inform the structure and use of ecological indicators to define policy scenarios in valuation surveys. The approach begins with a formal basis in ecological science and extends to relationships between attributes in respondents’ preference functions and those used to characterize policy outcomes. The resulting welfare measures are designed to be unambiguously linked to models and indicators of ecosystem function, are based on measurable and unambiguous ecological outcomes, and are more easily incorporated into benefit cost analysis. Performance of the developed methods is illustrated through an application to diadromous fish passage restoration in a Rhode Island watershed. Results suggest that less structured treatments of ecological change within stated preference surveys can omit information that is essential for the estimation of nonuse or indirect use values and relevant to respondents when determining WTP.