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003090 Rod Kuharich, Director 2 endangered fishes in accordance with the Wolford Mountain Reservoir and 15-Mile Reach PBO. A total of 3,857 acre-feet of water was released from Denver's Williams Fork Reservoir in accordance with the 15-Mile Reach PBO. When flows continued to remain low late into the summer, the Upper Colorado River Endangered Fish Recovery Program (Recovery Program) requested a short-term contract for 10,000 acre feet of water from Green Mountain Reservoir. The contract was approved quickly, and 10,000 acre feet of water was released from Green Mountain Reservoir to support flows in the 15-Mile Reach. The releases from Wolford Mountain, Williams Fork, and Green Mountain reservoirs significantly help to meet the target flows while reducing the impact on the Fryingpan River. Reclamation will be providing a separate report documenting the contributions of Green Mountain Reservoir, Ruedi Reservoir contents, and flow conditions in the Fryingpan River. The enclosed chart displays the progress the Recovery Program has made in sharing the burden or providing fish flows among both east and west slope water users. Benefits of Maintaining FWS Target Flows. The Service feels that maintaining the flow regimes necessary to support endangered fishes is very important and dry years like 2000 are particularly stressful to endangered fishes. As the number of adult endangered fish increases in the 15-Mile Reach, the importance of meeting the flow recommendations there becomes greater; i.e., when numbers are low, reproduction primarily limits the ability of the population to increase; when numbers become high, the amount of suitable habitat becomes limiting. The flow recommendations were designed to maximize the amount of optimum habitat for adults and thereby increase the carrying capacity. The flow augmentation from participating reservoirs was critical in providing adequate habitat for the Colorado pikeminnow that inhabit the 15-Mile Reach. Flows in late summer of2000 would have dropped off dramatically in mid-September to about 581 cfs or lower without the augmentation of flows provided by water users. Responses of the fish community to flow augmentation are difficult, if not impossible, to quantify on a short-term basis. As described above, the objective is to provide room for a growing population of Colorado pikeminnow, which we now appear to have, and in the future for razorback suckers if augmentation efforts prove successful. Annual reports for two studies dealing with the 15-Mile Reach monitoring in 1998 to 2000, including the population abundance survey, are included for your review. As noted in the reports, both studies are scheduled to conclude in 2001 as the Recovery Program begins to rely on population point estimates to evaluate how recovery is progressing to achieve population goals. After reviewing the enclosed, it became apparent that the requirements for annual reporting need to be revised to include a period of time necessary to detect a population