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priate to implement as experiments by the stakehold- ers and managers, (2) to conduct and communicate peer-reviewed research relevant to management deci- sion needs and to better understand factors governing potential responses to management actions, (3) to provide scientifically sound and defensible experimental designs for management experiments and to ensure that moni- toring programs yield useful information, and (4) to structure the timing of monitoring and research results to the extent possible in a way that affords the Adaptive Management \Vork Group (see section on Collaboration, p. 9) and the Secretary of the Interior the best available scientific information to consider in their management decisionmaking. Assessing the state of knowledge about the eco- system to be managed adaptively is a key early activity of most adaptive management initiatives. This type of assessment is most eflcctively done by using a conceptual model that collaboratively engages scientists and stake- holders to agree on what is known about processes that operate within a given ecosystem and to examine possible interactions by using a computer model. The computer model provides a conceptual, but not necessarily predic- tive, capability to consider ecosystem responses to experi- mental management actions (see text box on p. 12-13). Modified Low Fluctuating Flow Alternative and Experimentation In addition to examining the status and recent trends of key biological, cultural, and recreational Overview 7 resources, this report explores the effects of the imple- mentation of the MLFF alternative, which specifies dam operations under normal conditions and includes experimental habitat maintenance flows and BHBFs when certain conditions are met. Under normal condi- tions, the MLFF alternative allows for dam releases to fluctuate no more than 8,000 cfs per day and generally not to exceed 25,000 cfs except during periods of high regional runoff or for experimental flows (table I). In addition, the MLFF alternative constrains the hourly rate at which flow changes can be made, known as upramping and downramping. Habitat maintenance flows as described in the EIS are high, steady dam releases within powerplant capac- ity (33,200 cfs at full reservoir elevation) for 1 to 2 weeks in March, although other months could be considered under the GCDAMP. By contrast, BHBFs are infre- quent high releases that are at least 10,000 cfs greater than allowable peak discharge but not greater than 45,000 cfs. Also, BHBF releases are timed to occur when releases in excess of powerplant capacity are required for dam safety purposes. ~10re recently, the term "experi- mental high flows" has been used to describe experimen- tal flows that exceed powerplant capacity and range from 42,000 to 45,000 cfs. Habitat maintenance flows differ from BHBFs and experimental high flows because they occur within powerplant capacity and were anticipated to occur in most years. The two types of releases, which had similar purposes of re-forming backwaters and maintaining sandbars, were not to be scheduled in the same year, and neither was to occur in a year when there 1962 20,000 gallons of poison applied to 500 mi of the Green River to kill native fish and establish a trout fishery, resulting in the unintentional killing of fishes as far downstream as Dinosaur National Monument 1964 Glen Canyon Dam power generation starts; National Park Service ends a 40-yr program of planting rainbow trout (Oncorhynchus mykiss) and brown trout (Salmo trutta) eggs and fingerlings in tributaries of the Colorado River within Grand Canyon 1963 U.S. Supreme Court held in Arizona v. California that, as a result of the Boulder Canyon Project Act, California held an allocation of 4.4 maf, Arizona 2.8 maf, and Nevada 300,000 acre-feet of Colorado River water