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quality conditions have changed since construction of'the Aspinal Units, i.e., water temperature, and conditions may be unsuitable for spawning. Conversely, adult squawfish in the Gunnison River may have historically exhibited downstream movement to spawn somewhere in the Colorado River and returned up the Gunnison after spawning, a situation similar to that exhibited by squawfish in the Yampa and White rivers. The number of sub-adult and adult squawfish currently occupying the reaches upstream of Redlands is considered low. If the objective here is to reestablish a "downstream-to-spawn" situation, then it would be necessary to reestablish a Gunnison River squawfish population or stock, which would require using fish from hatcheries or grow-out ponds. These fish would probably be stocked as juveniles upstream of Redlands, as they would need to develop an affinity for the Gunnison, if current hypotheses regarding "homing" are correct. Fish stocked as juveniles may require a minimum of 5 years or more to mature in the Gunnison River, and it would be several years before these fish use a fish passageway at Redlands. 4) Fish passage should not be used if it is soley to add habitat that is not currently limiting. If sub-adult and adult habitat is not limiting in reaches currently occupied, simply adding more habitat in other reaches cannot be considered beneficial to the population. The river reach immediately upstream of the Price Stub Dam is an example. Similarily, the use of fish passage would not be advisable to exchange or "trade" adult habitat that may be potentially impacted for other nearby adult habitat, particularly if this habitat is not limiting downstream of the area to be lost or impacted. An example of this is a 15-mile reach of Colorado River near Grand Junction which may be impacted in low-water years. Portions of the Gunnison River upstream of Redlands Diversion have been identified as providing adult habitat for that lost in the 15-mile reach. Barrier Type: High Item 1. Consequences: Complete upstream and downstream obstruction, regardless of flow regime 2. Solution: 1) The cost to construct a fish passageway at a high structure would obviously be high. The cost of a fishway at a high structure could not be appropriately projected even from the design and costs of the proposed fishway at Redlands. Encorporating the design of a fish passageway with the design and construction of a new instream barrier, such at a large dam, would be more desirable, both practically and financially, than retrofitting an existing structure. This philosophy is used in the northwestern and northeastern U. S. In the likelihood that a project gains approval that will create a high barrier, the project proponent 14