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<::> reader that what is presented is a range of possibilities given probable conditions and that the recommendations made are preliminary and based on best available information at the time. l~ ..... ~)' c..;t QO Success of the San Juan Recovery Program depends upon a positive response of the targeted fishes to the flow recommendations. A standardized monitoring program that focuses on specific biological response variables (e.g., larval fish density below known spawning areas,juvenile density in autumn from critical habitats, numbers of adult fishes on spawning areas) within a hydrologic and geomorphic context is.essential for at least a decade. Because the Program uses an adaptive approach the models and flows can be adjusted during the monitoring as information is gained. General Suggestions for Improvement Non-native fishes. The report does an excellent job of describing lhe documented and suspected impacts of non-native fishes to the targeted fishes. Additionally, it is indicated that a more natural hydrograph may benefit native over non-native fishes. However, it is unlikely that non-natives will be extirpated by a natural flow regime and their continued impact may remain an impediment to achieving the full restoration potential of the native San Juan fish fauna. I suggest this reality be considered in relation to expectations of the benefits of restoring a natural hydrograph and incorporated into your adaptive management strategies. RESPONSE: The Biology Committee is well aware of this potential and has incorporared it into its future activities. The amount of methodological details in Chapter 4: Response to Research Flows, seems excessive and out of balance relative to the biological information presented elsewhere. 1 believe it detracts from the reader grasping the main geomorphic effects of whal the research flows accomplished. Perhaps methodological details and the hydrological nuances should be summarized elsewhere. In general, a bit more even treatment of biological and physical information is suggested. Having biologists edit the physical sections and visa-versa is a good approach to accomplish this. RESPONSE: We understand the basis of the concern. However, since the flow recommendations are based so heavily in the hydrology/geomorphology relationships, earlier drafts were criticized by others for not including sufficient detail. The detail was added in response to those criticisms. If high flows are required to move materials and they ultimately move through the system. Where do new materials (e.g. cobble) come from? Contrasting lhe relative importance of lateral sources (some of which may come from bank erosion of adjacent private lands) and downstream transport in a system where Navajo Dam has reduced supply is an important consideration. What will be a range of projected channel configurations in 50 years and where will cobble come from if the system is laterally and longitudinally constrained, or is it? RESPONSE: Navajo Dam cut off the upstream cobble source. The Animas River still provides a small cobble source from upstream as does the LaPlata River (both unregulated). It is likely that the bulk of the new cobble in the system will come from bank erosion and newly formed secondary channels created during over-bank flow events. With aflow regime reduced from historic pre-dam conditions, cobble transport is also reduced. Fortunately, the channel is not laterally constrained over much of its length once on the Navajo Reservation (Below RM 158). While we have not attempted to predict the long term cobble balance. Comments and Responses Flow Recommendations Drah Report Galat-2