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' installed and operated two of these structures in the past, one at the former Walter Walker Wildlife Area west of Grand Junction, and one at the drainage ditch ' and channel connecting the smaller pond to the river at this site. The advantage of using a fish trap is that fish movement to and from the pond can be regulated and monitored directly. However, the disadvantage of a fish trap is that they ' are labor-intensive because they must be routinely checked, fish appear to be "trap shy" , and beavers are attracted to such areas. Water levels in both ponds will be self-regulating by surface and ground ' water irrigation returns and from the river. Although both ponds will be connected to the river, it is expected that the smaller pond that is graded will drain and almost dry up following runoff. Water level elevation in the larger ' pond will be lowered slightly from its present level following recession of high water. However, the pond water level should be maintained even during extreme low flow events in the river because of the "bathtub-shaped" morphometry of the ' larger pond and in-flow from irrigation returns. Even if water levels in the ponds and water quality conditions (e.g. low dissolved oxygen) deteriorate, fish can return to the river. ' The integrity of the riverside dike will be closely monitored. The width of the dike will be monitored to determine if the river will eventually breach the dike. In the event that the dike is breached by the river, the site will be ' reassessed for its suitability for further biological evaluation. Impacts from Operations on Native Flora and Fauna ' Native Colorado squawfish should benefit when the larger pond is connected to the river. Ponds connected to the river should provide important habitat to ' native fishes. Fish could move into and out of the pond at will during the year and have access to the more productive backwater where densities of benthic and water column invertebrates are available. Native adult Colorado squawfish have ' used the few ponds in the Grand Valley that are connected to the river, particularly during spring high flows. The connected pond will serve as a velocity shelter and conditioning area for adult endangered fishes during high stream flows. ' The smaller pond to the north has been connected to the river for several years and has been used by Colorado squawfish in the past. This pond will be ' available only seasonally during the high-water period to endangered fishes because it will drain following high water. No razorback sucker captures have been recorded in this pond, although only seven adult razorback sucker have been ' captured from the Colorado river since 1988. PROPOSED EVALUATION ' factors to be Evaluated t Evaluations are essential to determine if the action was beneficial, detrimental, or had no affect on the intended target species. Each of the five selected sites selected were intended to be "pilot" or "test" sites for ' 16