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--Saving razorb-acks-reCJ.uires-quick -action,bioIogists-say- From WETLANDS, Page 1 'The best wetlands on the entire Green River are at Ouray and Jensen. Utah," said Ed Wick, a biologist with the National Park Service in Fort Collins, Colo. "Major steps toward recovery of razorbacks in the Green River could be accomplished there." Most wild razorbacks are old adults; very few of their young have been found, researchers say. "This is about the most important project we have ever taken on for razorbacks," Wick said. "These fish live to a maximum of 35 or 40 years and are starting to die off. It's impor- tant to do something quickly." The plight of endangered rawrback suckers, Colorado squawfish, humpback chubs am bonytail chubs is believed an indicator of the oyera1l health of the river ecosystem. Scientists believe sav- ing rre "weakest link" also will benefit the environment am orrer species thele, Researchers bega~ verifying the value of wetlands to endangered fish after a study last summer showed sig- nificantly higher growth rates in a group of 2-year-<>ld razorback suckers placed in wetlands compared to a simi- lar group in river channel "backwa- ters." Initially 3 to 7 inches long, the fish grew by as much as I inch in the wetlands - nearly four times the growth ofthose in backwaters. Rapid early growth helps keep the fish from being eaten by larger fish. "There's no question that giving razorbacks access to flooded bottom lands (wetlands) is the best way to recover them," said Tim Modde, a biologist for the U.S, Fish and WIldlife Service in Vemal, Utah. 1b giye the fish access to wetlands near Jensen, 1he Nature Conservancy, a national conservation organization, is working with the Recovery Program to restore several hundred acres of a wet- lam downstream of Dinosaur National Monument. The wetland is near two key Green River spawning sites for rawmacks. 'The thought is that without access to a nearby wetland like this one, young rawrbacks may be swept all the way down to Lake Powell or be eaten by non-native fish in the river," said Robert Wigington of The Nature Conservancy's office in Boulder, Colo. Also important to endangered fish are high river flows during spring runoff. Biologists believe such flows "cue" native fish to spawn. In addi- tion, ifhigh river flows were sustained for several weeks, wetlands could stay fu1I1onger, the food base could reach maximum leye1s, and endangered fish could grow more quickly. Opinions differ on whether the Recovery Program's work with wet- lands would help or harm other wildJife species, Removing dikes at the river's edge could allow wetland water levels to rise during spring runoff and drain when flows recede. When wetlands are managed for waterfowl, water levels are kept high- er for longer periods. "But if the surface area of the wet- lands is increased (by higher flows), shore birds, waterfowl and other wildlife species will undoubtedJy ben- efit," Modde said, High selenium concentrations found near fish spawning sites From SELENIUM, Page 1 hann endangered Colorado Ri ver fish. according to Bruce Waddell, a biolo- gist with the U.S. Fish and Wildlife Service in Salt Lake City. Federal agencies found selenium concentra- tions of 60 to 70 parts per billion at the confluence of Ashley Creek and the Green River, which is key habitat for endangered Colorado squawfish and is near the primary known razorback sucker spawning ground in the upper Colorado Riyer Basin. In Ashley Creek iributaries upstream, concentrations as high as 10,000 to 15,000 parts per billion have been reported. The state of Utah's standard for protecting aquatic life is no more than 5 parts of selenium per billion in water. "We have source points of selenium that no one knew about six years ago," Waddell said. "I don't think se1eniwn is the primary problem (for end an- gered fish), but it is a compounding factor and one we need to deal with." Muscle tissue samples taken from razorbacks in the Green River near Ashley Creek and Stewart Lake showed selenium concentrations aver- aging about 25 parts per million. Scientists believe that in fish muscle tissue, more than 8 parts per million of selenium can cause reproductive prob- lems. (To test for selenium, a small tis- sue plug is removed from the fish and analyzed without harming the fish.) Effects on birds near Stewart Lake already have been severe. Researchers have found waterfowl embryos with no eyes, abnormally short legs and extremely defonned feet, Waddell said, Leakage from the waste water treat- ment facility near \t:mal contributes the largest amount of selenium in this area. OIanging that would require redesign- ing sewage treatment lagoons. Solutions for the irrigation drain projects near Vernal.am Jensen may include chang- ing irrigation practices from flood to 2 sprinkler, managing waterfowl areas different! y and treating or diluting con- taminated water. Considerable selenium also is pre- sent in the Price Riyer, a tributary to the Green, But if endangered fish in the Price Riyer are not in the pre-spawning stage, they may not have reproductive problems, Waddell said. Higrer flows in Colorado's Yampa and White rivers dilute the selenium am are not belieyed to pose a problem for wildlife. Interagency specialists on the National Irrigation ,Water Quality Program are working with local citizens to fin! the best ways to reduce selenium in the Green River. Because this issue already is being harxI1ed by several government agencies responsible for environmental contami- nants and water quality, the Recovery Program has decided to limit its role to monitoring and supporting cleanup efforts. - By Connie Young