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U00597 knowl edge on the subject, why certain actions have been taken by the Recovery Program participants, and rationale for taking these actions. 1. Some ~ersons and one organization were concerned about the negative impacts on piscivorous birds if nonnative fish species were removed from floodplain ponds along the Upper Colorado and Gunnison rivers. Mitchell (1995) identified 308 ponds -- 253 along the Colorado River with a total area of 721 acres and 61 along the Gunnison River with a total area of 197 acres. Mitche77 also reported that most of these ponds were less than 5 acres in surface area. The present plan is to remove nonnative fishes from about 25 ponds annua77y with a total of about 150 ponds by the Year 2002 (Martinez and Nesler 1996). In reality, mechanical or chemical control techniques would be employed in about 10 ponds during 1997. Some of the gravel-pit ponds are too deep and contain only a sma77 area of sha770w water that can be used for feeding by wading birds. In the floodplain areas where these ponds are located, there are also shallow backwaters and embayments on the river that contain sma77 fish that are available to piscivorous birds. Aquatic diving birds such as grebes and mergansers have larger reservoi rs with deeper water as a lternate feeding areas. Therefore, any negative impacts on birds that use fish for a large part of their diets should be minimal. Some ponds will be restocked with young endangered fishes or sportfish so not a77 ponds wi77 remain fish7ess. The Colorado Division of Wildlife plans to stock and manage warmwater fish species in some of the ponds that are above the 50-year floodplain to add diversity of sportfishing opportunities. The young warmwater fishes will be available as food for the piscivorous birds. Still other ponds will be used as grow-out ponds for endangered Colorado River fishes. We expect some predation on these fish by piscivorous birds. Ponds that remain barren of fish will quickly recolonize with zooplankton and benthic organisms that serve as food for shorebirds and waterfowl. Therefore, these ponds wi77 continue to have birds for wildlife-related activities such as observation and photography. Some of the floodplain ponds wi77 be reconnected with the river as artificial embayments as part of the Recovery Program's habitat restoration effort for the endangered fishes. These ponds will contain small fish that would be available to fish-eating birds. Therefore, removal of nonnative fish species from.some of the floodplain ponds along the Upper Colorado and Gunnison rivers will not result in complete elimination of small fish that serve as food for birds. 2. Several persons expressed concern that control of nonnative fish species may not be adequate because there are a lot of ponds along the Colorado and Gunnison rivers and many landowners may not cooperate. 28