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<br />Fishfa.cts, etc.
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<br />Fish population trends reported ,
<br />In a'seven-year summary of efforts
<br />, to monitor endangered fish populations
<br />in the, upper Colorado River Basin,
<br />state and federal biologists reported
<br />several trends~ , " ,
<br />. Introduced non-native fish coin~ ,
<br />posed 75 to 99 perc(Ont of all fish col-
<br />lected. The most frequent non-natives
<br />were fathead minnow, red shiner and
<br />,sand shiner. , '
<br />. Young-of-the-year (newborn) Col-
<br />orado squawfish were more abundant
<br />'in the Green River than in the Col-
<br />orado River. '
<br />" .' Razorback ,suckers' have declined
<br />, considerably in recerit, ye;us. Only' one
<br />razorback was captured in the White
<br />River, one in the Colorado and norie in
<br />the Yampa. Biologists found- them
<br />, every' year in the Green River" but the
<br />numbers appear to be dropping.'
<br />., . Relatively large, apparently stable
<br />_ populations of humpback chubs' exist
<br />, in the Colorado River' near the Utah-
<br />Colorado state line. '
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<br />Program wins oommunicationaward
<br />The Recovery Program for Endan-
<br />geredFish of the Upper Colorado
<br />River wOll a second place award in a
<br />1994 statewide' communication con-
<br />test. The Colorado chapter of the Pub-
<br />lic Relations Society of Anierica hon-
<br />ored the Recovery Program's Infonna- ,
<br />,tion and Education Progriun. with a
<br />, "Silver Pick" award in the category of
<br />public ,affairs programs' ' '
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<br />Dams ease droughfs impact on fish
<br />, Though clanis have pushed some nae
<br />, tiveColonUlo River fish toward extinc-
<br />tion, last summer they niay have been
<br />the fishes' saving grace. Water releases
<br />from dams during last year's drought _
<br />may have helped endangered fish sur-
<br />vive one of the driest years on record.
<br />" For', example, at Northwest Col-
<br />orado's Ruedi Reservoir, the Bureau of
<br />Reclamation released about 200 cfs of
<br />water in late summer to benefitendan-
<br />gered fish. During a similar yeai in the '
<br />past, the river likely could have gone
<br />dry.
<br />. In southwest Colorado on the Gun-
<br />
<br />P~to by Ed Wick
<br />Larval Fish Laboratory assistant Steve Meismer sortS, counts and measures lar-
<br />val fish, collectEicl from the Green River last summer. Researchers were excited
<br />ttl find 1,200 one-month old razorback suckers. Previously, the scientists had
<br />located only adu~ razorbacks more than 25 years old. '
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<br />nison River, flows were kept ne~ nor-
<br />maL ' ,
<br />. The Green River was maintained,'
<br />at 'I ,600 to 1,800 cfs. In previous dry
<br />years, flows would have dropped to
<br />800 ds.,' '
<br />, , . In coIitras~ flows on the Yampa ...:,..
<br />, where 'no danls exist - dropped as low
<br />as 8 cfs at Maybell, Colo. At that time
<br />of year, the Yampa nonnally flows at
<br />, about 200 cfs. ' ' ' ,
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<br />Young razorbacks found In Green River
<br />Biologists discovered more than
<br />, 1,200 one-month-old razorback suck-
<br />ers in the Green River last summer.
<br />This"find elated researchers, who pre-
<br />viously had found old adult razor-
<br />backs, but very few young. _ ,
<br />Researchers used traps' specially
<br />equipped with lights to attract the fish:
<br />During May and June, the scientists
<br />placed the traps overnight in slow-,
<br />moving aieas in the Green River from
<br />Flaming Gorge Dam to Lake Powell.
<br />- The larval fish, which are less than I
<br />inch long, swam toward the light and
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<br />- through tiny slits in the trap. Before
<br />sunrise, researchers pulled the traps
<br />, out ofthe water and removed the fish.
<br />"Finding this many razorback larvae'
<br />tells us there could be millions of them
<br />in the Green River," said Darrel Snyder
<br />at Colorado State University's Larval
<br />, Fish Lab. " ' .
<br />, But nearly all of these young fish
<br />die before they are even 2 months old.
<br />, The problem, researchers believe, is a
<br />combination of predation by red shin-
<br />ers; green sunfish and other ,non-native
<br />species, lack of adequate food in the
<br />river channel and ciani-related changes
<br />, in river flows: By removing dikes and
<br />, other. barriers between the river' and
<br />nearby flood plains, water could flow
<br />,in, carrying endangered fish along with
<br />it. Feeding iIi. these nutrient-rich habi-
<br />tats would allow the young fish to
<br />grow large enough to stand a'
<br />fighting chance in the riverE)
<br />The Recovery-Program is
<br />working to restore a nwn- ~...
<br />ber of these flood plain ~
<br />'habitats. ' , '
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