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Summary <br />Stream-riparian ecosystems are among the most productive, biologically diverse and threatened <br />habitats in arid regions, including the American Southwest. Standardized assessment protocols <br />are needed in order to effectively measure the current health and functional condition of these <br />ecosystems, as well as to serve as a guide for future restoration and monitoring programs. <br />However, most existing survey methods either focus on only a limited subset of the different <br />components of the ecosystem, base their evaluations upon some hypothesized future state rather <br />than upon the current conditions of the reach, and/or rely heavily upon subjective judgments of <br />ecosystem health. We describe an integrated, multi-dimensional method for rapid assessment of <br />the functional condition of riparian and associated aquatic habitats called Rapid Stream- <br />Riparian Assessment (RSRA). This method evaluates the extent to which nat~iral processes pre- <br />dominate in the stream-riparian ecosystem and whether there is sufficient terrestrial and aquatic <br />habitat complexity to allow for the development of diverse native plant and animal commuiu- <br />ties. <br />The Rapid Stream-Riparian Assessment involves a quantitative evaluation of between two to <br />seven indicator variables in five different ecological categories: water quality, fluvial geomor- <br />phology, aquatic and fish habitat, vegetation composition and structure, and terrestrial wildlife <br />habitat. Each variable is rated on a scale that ranges from "1", representing highly impacted and <br />non-functional conditions, to "5", representing a healthy and completely fiulctional system. <br />Whenever possible, scores are scaled against what would be observed in control or reference <br />sites that have similar ecological and geophysical characteristics, but which have not been heav- <br />ily impacted by human activities. The protocol was designed to be used both by specialists and <br />by non-specialists after suitable traiiung. It is particularly appropriate for small to medium sized <br />streams and rivers in the American Southwest, but with slight modification it also should be <br />applicable to reaches in other temperate regions and geomorphic settings. <br />2 <br />