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