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d'b Colorado Division of Wildlife December 1, 1994 Page 3 5. Walleye were identified as a threat to all endangered . fish by the experts surveyed by Hawkins and Nesler (1991). ..--Th~se experts noted that razorback sucker young and Colorado squawfish were especially vulnerable to walleye predation, and that walleye posed a threat of competition in particular to Colorado squawfish. The potential for conflict with endangered species from stocking these nonnatives in the sites the Division proposes is great. Aside from Harvey Gap, Elkhead, and Highline reservoirs, all sites proposed for stocking are ponds that lie within the floodplain of the Colorado River. The Division is incapable of preventing nonnative escape from these ponds when the river reaches flood stage sufficient for communication with these ponds. Thus, stocking in ponds susceptible to flooding creates the potential for interaction with endangered species. The harm to endangered species which will result from such interaction is prohibited by the Endangered Species Act, conflicts with the Divisionis duties under the Colorado Nongame, Endangered, or Threatened Species Conservation Act, and is inconsistent with Coloradols position as signatory to the Recovery Program. In addition, all ponds located within the 100 year floodplain are designated critical habitat for the endangered Colorado river fish. Stocking in these locations constitutes an adverse modification of critical habitat. The Endangered Species Act prOhibits such adverse modifications. Elkhead reservoir and Highline reservoir, while not in the Colorado River floodplain, have their own problems: 1. Elkhead Reservoir: The Division admits that fish stocked in Elkhead reservoir are not secure by noting that "escapement potential is high. II But the Division proposes no measures to reduce nonnative escape. A recent article in The Denver Post (attached) details the consequences of past stocking in Elkhead, which include predation on endangered fish and a costly and laborious effort to remove northern pike from the Yampa system. The escape route from Elkhead leads directly to critical habitat in the Yampa River. The Divisionis assertion that only adult Colorado squawfish are found in the Yampa River is false. Humpback chub have been collected in the ~rQ~l? ._'__n Mountain Canyon area~' --lilhthe Little Snake River, and in the. lower Yampa-Green system, which r~mains the last stronghold for all four endangered Colorado River fishes (USFWS, 1993). Bass escaping from Elkhead have~n~mpeded access to these habitats. 2. Highline Reservoir: The Divisionis assertion that stocking channel catfish and walleye in Highline reservoir will not impact endangered fish is pure speculation. The Division