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INTRODUCTION This report presents results of research regarding the development of indices of biotic integrity for perennial streams in New Mexico. To date, our research efforts have focused on understanding biota-environment relationships and how such knowledge can be employed in the development of indices of biotic integrity (IBI's). Biotic integrity can be defined as the condition in which the biota of a given system have an organizing, self-correcting capability to recover from disturbance and regain an end-state that is normal and good for that system (Regier, 1993). "Normal and good" can be something other than pristine or naturally whole. Biotic integrity and health of the environment are not new concepts (Karr, 1993). Monitoring of the environmental health of freshwater systems has progressed from the near universal measurement of BOD earlier in this century, to measurement of a broader spectrum of chemical and physical quantities, to incorporation of biota into indices that are reflective, at least to some extent, of environmental health (e.g., Karr, 1981; Hilsenhoff, 1982). In spite of this progression, and even with the acknowledgment that biota provide better interpretability than chemical parameters (Steedman and Haider, 1993), there is much to be learned. Indeed, the "agony of community ecology" (Lewontin, 1974) is that we often do not know which variables are important and we lack simple quantitative models to describe environmental variation and its effect on the biota (Keddy et al., 1993). IBI's have important potential uses in fisheries management and in watershed protection. When properly constructed, an IBI will identify sites where single or multiple stressors begin to cause species composition to differ substantially from expectation. Complementing this, IBI's offer easily observable measures of ecosystem response to management. JOB OBJECTIVES Determine the species composition of major macrobenthic invertebrate groups (Chironomidae, Ephemeroptera, Plecoptera, Trichoptera) at selected water bodies throughout the state. 2. Apply the collection of surface floating pupal exuviae of Chironomidae (Thienemann net technique) as a semi-quantitative method of determining species richness and relative abundance of Chironomidae alone as an indicator of water quality as compared with all major groups of macrobenthic invertebrates. The collections will be applied as a quantitative method of determining water and habitat quality as compared to the Chironomidae. 3. Concurrent collections of fish will be taken by the staff of New Mexico Department of Game and Fish (with assistance from contractors). 4. Compile physical parameters at each collecting site: elevation, mean depth, width, velocity, flow volume, substratum type(s), turbidity, temperature, pH, specific 3