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34 years to provide the same shape, timing, volume, and frequency. This information, when presented to the Biology Committee by Reclamation, resulted in agreement that the additional depletion of 57,100 acre-feet caused by the Project would be biologically acceptable so long as all other features of the reasonable and prudent alternative were fully implemented. The Service concurs. Future research is an important feature of the reasonable and prudent alternative. It was sufficient new information from research conducted as a result of the 1979 biological opinion that led to the reinitiation of Section 7 consultation for the Project. It is the implementation of research which will provide the Service with further information about the biological needs of the fish specific to the San Juan River Basin and how these needs can best be met. The future development of water in the San Juan River Basin, including the proposed remaining depletions of the Project, will be highly dependent on the outcome of the biological studies which are being required as part of the reasonable and prudent alternative. In making future decisions about endangered species, the Service must use the best scientific and commercial data available. The minimum study period necessary to conduct the studies was determined by the Biology Committee, Reclamation, and the Service to be 7 years. Any inability to deliver the flows under the third element of the reasonable and prudent alternative would likely prolong the research period. A study plan is being developed to address the conduct of the research. This study plan will focus on a biological response to the operational changes of the Navajo Oam (Element 3), but also will address other impacts such as water quality, water temperatures, and migration barriers. During the research study period, the Navajo Dam will be operated under a variety of scenarios (wet, average, and dry) to mimic a natural hydrograph to re-create a high spring peak flow providing a gradually ascending limb followed by a gradually declining recession limb to low, stable flows throughout the summer, fall, and winter. The Service and the biological experts believe that this is the best opportunity available to bring the endangered fish back from the brink of extirpation in the San Juan River. By returning the river to a more natural hydrograph and raising the spring peak flows, the Service believes there will be an increase in reproduction and recruitment of the endangered fish in the San Juan River. This operation of the Navajo Dam is the most important feature of the reasonable and prudent alternative both for the resEarch period and for the long term. In order for there to be an additional permanent depletion of 57,100 acre-feet of water from the Project, there must be a guarantee that the Navajo Dam will be operated to mimic the natural hydrograph based on research for the life of the Project. Releases for the endangered fish will be legally protected to and through the endangered fishes habitat to Lake Powell. However, until the research is completed, the required water delivery schedule for the life of the Project (in terms of hydrograph shape, timing, volume, and frequency) is unknown.