A hierarchical evaluation system for characterizing watershed ecosystems for fish habitat

We present an evaluation system and framework for determining the relations between processes that generate physical features and how these features are used by fish. This information is essential for long-term management of fish habitat within watersheds. The model is hierarchical at three scales: watershed, reach, and site. Physical characteristics at these scales are separated into attributes, features, or variables that provide information on cause-response relationships. An evaluative framework is proposed along with a logical framework to guide analysis. The framework includes a functional analysis of physical characteristics and processes that generate physical habitat and a functional analysis of habitat requirements related to life cycle of an indicator species. An example of a life stage - state analysis is presented. Concepts of ''health,'' ''integrity,'' and ''fit'' are used to assess the physical states and conditions of the environment to determine the potential fit for a species based on its life-cycle requirements.