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<br />- -'Refuge' -ponds -constructed -to -hold -rare fish-
<br />
<br />By Connie Young
<br />Public Information Specialist
<br />Colorado Dlvisk," of Wildlrl.
<br />GRAND JUNCTION, Co10.-
<br />Endangered Colorado River fish can be
<br />protected from fuel and chemical spills
<br />and other catastrophic events in the
<br />river, thanks to six western-Colorado
<br />ponds constructed last summer.
<br />These "refuge" ponds for Colorado
<br />squawfish, razorback suckers, hump-
<br />back chubs and
<br />bony tail chubs
<br />were constructed
<br />by the U.S.
<br />Bureau of
<br />Reclamation on
<br />the Horsethief
<br />Canyon State
<br />Wildlife Area near
<br />Fruita, Colo.
<br />The ponds will
<br />allow biologists to
<br />hold endangered
<br />fish in Colorado
<br />River water without the perils that' a
<br />train w~ck, drought or other disaster
<br />could cause in the ri ver.
<br />"If there were an accident in the
<br />river, some populations of wild native
<br />fish could be gone for good," said Bob
<br />Caskey, manager of the Colorado
<br />Division of Wildlife's northwest
<br />region. "Removing some of those fish
<br />from the river and holding them in
<br />these ponds has given us an 'insurance
<br />policy' against that type of disaster."
<br />
<br />
<br />Photo by Dave Gales
<br />The six ponds
<br />cover 3,5 acres.
<br />
<br />
<br />Photo by Connie Young
<br />Mike Baker of the Fish and Wildlife
<br />Service sons Colorado, squawflsh
<br />before placing them In the ponds.
<br />
<br />Water that flows out of the ponds
<br />has created an oasis on the once-arid
<br />state wildlife area, expanding the wet-
<br />lands by about 60 acres and providing
<br />more habitat for ducks, geese, great
<br />blue herons, avocet, frogs and toads,
<br />Interagency cooperation was the
<br />key, according to Caskey. Using a
<br />Congressional appropriation for
<br />drought-relief purposes, Reclamation
<br />contributed $200,000 and constructed
<br />the ponds; the Division of Wildlife
<br />
<br />, , ,
<br />. .. , .. ...
<br />, " , Endangeiedflshlrlll1e
<br />',. 'HCli'sethle!Ciinyon P<>llds . "
<br />, ~ More than J,OOO s.:incl1l1atch-.
<br />ilry-raised Colorado, squaWfish.
<br />. from the Colorado Division of.
<br />Wildlife's research l1atchery in ,.,.
<br />Fort qollinswereadded to the
<br />p6ndsin AJiriI1993. , '.' ,," ,,'.., . ,., '"
<br />; Also in Apfll,f001,year'0Id "
<br />'. razorback Suckers werebrliught
<br />. inio the ponds from a hatchery
<br />, in Ouray,Utah. When these fish ,
<br />areabOuf12 Inches long; they
<br />'will be stoeked In theeolorado",
<br />,. 9fGUnnisClnrivEir. ....' ',' .."', .. ','.,'.' '.
<br />.. In May 1993;liiolo9isiS plan..to
<br />place 6(ll1aicl1ery-raised bony,"
<br />tailcrubs In thepohdS. . ,.".", .
<br />; Plans can for cOlleCtlrig 30 wild '
<br />, aduK l1urnpliaCli chi.ibs from the '
<br />< theCokirildoRiver this sUmmer
<br />", . arid hOlding thein iri the ponds. '.
<br />... .
<br />
<br />contributed $30,000, raised the squaw-
<br />fish and will manage the state wildlife
<br />area; and the Fish and Wildlife Service
<br />will operate and manage the ponds.
<br />The Denver Water Department and
<br />other water conservancy districts
<br />donated a total of $50,000 for raising
<br />the squawfish in Fort Collins, Colo.
<br />"This project was up and running in
<br />less than a year," he said. "A coopera-
<br />tive effort like this is an example of
<br />how 'good government' can work."
<br />
<br />Bird predation, nitrogen overload kill rare fish in ponds
<br />
<br />Biologists haye discovered and
<br />partially solved two problems for
<br />endangered fish in the Horsethief
<br />Canyon refuge ponds: predation by
<br />birds and excess nitrogen gas in the
<br />water.
<br />A flock of 30 to 40 ducks is
<br />believed to have eaten a large num-
<br />ber of 4-inchhatchery-spawned
<br />Colorado squawfish that were placed
<br />in the refuge ponds last August. Also,
<br />pond water became supersaturated
<br />with nitrogen gas this winter, result-
<br />ing in gas bpbble disease that killed
<br />11 of 13 hatchery-raised bony tail
<br />chubs in the ponds and possibly some
<br />of the squawfish.
<br />"We had a substantial loss of
<br />
<br />squawfish to mergansers (a duck
<br />species) this spring," said Frank
<br />Pfeifer of the U.S. Fish and Wildlife
<br />Service in Grand Junction, Colo.
<br />.. And apparently, with ice on the
<br />ponds and water being pumped in
<br />under pressure through a 6,OOO-foot
<br />pipeline from the Colorado Riyer,
<br />nitrogen built up to a point where it
<br />began killing some of the bony tails
<br />and squawfish,"
<br />To eliminate the bird predation
<br />problem, Pfeifer and his crew have
<br />suspended a mesh net about 4 feet
<br />above the surface of the pond holding
<br />the small fish.
<br />The nitrogen problem will be
<br />solved with aerators or packed
<br />
<br />4
<br />
<br />columns that strip gas from the water.
<br />The fish that died were hatchery-
<br />raised offspring of wild endangered
<br />fish. Though important in testing the
<br />suitability of the ponds for wild fish,
<br />the hatchery fish were not considered
<br />critical to the future of the Recovery
<br />Program.
<br />"None of these fish was taken
<br />directly from the Colorado Riyer
<br />Basin, and hundreds of their siblings
<br />are still being held in other
<br />hatcheries," Pfeifer said. "Of course
<br />we don't want to repeat these losses,
<br />so it's good 'we discovered these
<br />problems before the majority of the
<br />fish arrived."
<br />-By Bill Haggerty and CoMie Young
<br />
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