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<br />4-inch openings between bars. The secondary screening device also consists of a rack of vertical <br />steel bars; however, the opening between these bars-will only be 114-inch wide. No "take" of <br />endangered species is anticipated by the constrUction and operation of the fish passageway. The <br />screening devices located at the fish passageway entrance prevent fishfrom entering the structure <br />and being drawn into the city of Grand Junction's pumping plant intake. The location of the fish <br />passageway on the inside of a major river bend (away from deeper and faster flows) and the <br />perpendicular orientation of the fish passageway entrance to the flow of the river also prevent <br />"take. fI <br /> <br />The status of endangered fish in the Gunnison River under present conditions has been clarified. <br />Historical accounts by early senlers along the Gunnison River indiCOle the Colorado sqUllYlifish <br />and razorback sucker were common in this area. The numbers have declined to the point that <br />both are very rare as indicated in the text. The only razorback suckers krwwn to occur in the <br />river upstream from the Redlands Diversion are fish stocked by the Service in 1994. A small <br />remnant population of Colorado squa"!fish are present upstream but rw recruitment of young has <br />been documented in this reach. During 2 years of extensive surveys in 1992-1993 only 5 <br />squal1!fish were found upstream from the diversion. <br /> <br />Non-native fish presenr in the Gunnison River include the smallmouth bass, channel catfish, <br />carp, sand shiner, fathead minnow, white sucker, black bullhead, killifish, largemouth bass, <br />green sunfish, rwnhem pike, and brown trout. A higher percentage of native fish occurs <br />upstream of the diversion dam and in this area afew rwn-natives such as the channel catfish are <br />very uncommon. The fish passageway will be operated to keep additional rwn-nativefish from <br />moving upstream. The passageway is designed to do this; it is recognized that this may rwt be <br />100 percent effective, bur it is considered a practical measure. It shauld be rwted that it is much <br />easier 10 keep the fish from moving upstream than it would be to keep them from moving <br />downstream. It is desirable to reduce or rwt introduce rwn-natives, such as channel catfish, <br />in the Gunnison River as they compete with the native fish, especially in wann backwater areas <br />that are very imponanrfor successful reproduction of native fish. <br /> <br />The 300 eft flow recommendation below the Redlands is preliminary and based on maintaining <br />water depth for fish to move upstream between the Colorado River and the passageway. River <br />cross-sections were taken in the 2.3 mile reach of the Gunnison River at several flow levels and <br />depth versus flow relationships were developed. Included in the 300 eft is 100 eft necessary to <br />operate the passageway. During the period of the interim agreement, these flows and their effect <br />on habitat will be monitored to provide data for final recommendations. <br /> <br />Critical habitat on the Gunnison River has been designated as occurring between the Colorado <br />River and the Gunnison's confluence with the Uncompahgre River. Radio telemetry data <br />indicates that the fish have moved a few miles upstream past the Uncompahgre confluence. <br />Upstream from Delta the river is restricted by a diversion dam--the Hanland Diversion Dam-- <br />and also colder waler released from the Aspinall Unit may have changed habitat conditions to <br />the point that they are unsuitable for some of the native fish. <br /> <br />53 <br />