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Rare razorbacks raised past ',danger zone' Biologists at the. Ouray National Fish Hatchery near Vernal; Utah, have captured. and successfully raised 27 wild razorback suckers to the "finger". ling" stage, a crucial point ihat greatly increases the likelihood the fish can survive outside captivity. . In the wild, researchers typically find razorbacks that either are 25 or mOre years old or are recently hatched; . rarely are any of-these fish found at the adolescent stage, The scientistS posi- tively identified the 4-inch fish.in.late August after'removing them. from a man-made hatchery" pond, . "The fingerling size has been the 'missing link' for tliese fish," said Ouray . Hatchery Manager Tom Pruitt. "That's why we're pretty pleased about this," There are only about. 500 adult. razorbacks left in the Green River, But based on recent findings, biologists estimate there may be millions of lar- val razorbacks in the. Green. River, They hope to help some of these young fish survive by raising them to adult- hood in ponds or wetlands. FISH PONDS Utah Division . of . Wildlife Resources biologist Wayne Gustaveson holds a. blueprint . showing ponds at the Wahweap Warmwalel' Hatchery. in soirthem Utah. nie ponds shown on the left were built in 1972 and are :used to raise small-mouth bass and hybrid striped. bass. Those' on the right were completed last fall and.. . already. have been used to. rear 3,000 bonytails... which wili. be stocked in the upper Colorado River this fail, and 2.000 razor- back suckers, iilso set for fall stocking in the Gunnison, upper Colorado snd San Juan rivers. Ground will be broken in October. on ponds seen in the center of the diagram. . Photo by"Connlfl Young The fish were collected two mont/is ago in specially.. equipped light-traps set in the Green River near J(m.sen, . Utah, At that time they were. V,-inch larvae, Using an identification tech- nique developed by the Larval Fish Laboratory at .Colorado. State. . University, the biologists placed. the fish in water-filled petri dishes and examined them under a microscope, From thousands of Sucker larVae, tlie biologists sorted out 92.they. thought . . were razorbacks and placed them in the hatchery pond. Of those, 27 sur- vived,the remainder died, either from disease or insect predation, . . ..Having. .been hatched in the. river, . !hese yourig razorbacks have the same . genetic make-up and possibly behavior as their wild parents, miling . them ' . ideal to produce young fish for stock- ing, researchers say, . "We can use these fish to. develop . future bro.od stock that have the same genes as wild fish, which is key to the . fishes' survival, groWth and reproduc- tion," said U:S, Fish. and Wildlife 5 Service biologist Bruce Haines, The fish shoUld have produced off- spring in about five years, at which time the aduits will be returned to the river, . At larger sizes, the restocked razorbacks . should be able to survive and avoid pre- dation, Researchers hope. to use these same techniques to captUre and raise more.of these rare fish in the future, Also, ..because these fish were cap- tured near the primary known razor- . back.spawning site. in the upper Colorado River Basin, they may be '''imprinted'' to. this site and are more likely to retUrn to this area to spawn, .' Biologists believe ritillions Of huval . razorback' suckers are spawned in the . . Green River each. year. Making wet- lands are made available to these small fish should greatly improve the.chances that they cari grow large enough to fend for themselves .in the river and eventu- . ally.be recovered, scientists say. . Razorback suckers evolved in the Colorado River Basin more than 4 mil- lion years ago, They,exist nowhere else on earth,