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Environmental Issues ENDANGERED SPECIES Originally a muddy, brown and seasonally warm river that overtlowed its banks, portions of the Colorado River are now cold, clear and channeled, the result of dams, reservoirs and engineering. Unfortunately, these changes along with the introduction and propagation of non-native fishes have proven to be detrimental to native fish populations and natural ecosystems along the Colorado River. In 1994. the U.S. Fish and Wildlife Service (USFWS) gave special protection to 1.980 miles of the Colorado River and its tributaries to protect four native fish species: the Colorado pikeminnow, bony tail chub. humpback chub and razorback sucker. Although all four fish previously had been granted federal protection. the "critical habitat"' designation is expected to have an additional impact on the Colorado River and its users. The Upper Colorado River and San Juan Endangered Fish Recovery Implementation Programs. which include habitat restoration. fish hatcheries, flow regulation, bottomlands acquisition and structural improvements, i.e. fish ladders, to allow native fish species to return to spawning areas blocked by manmade structures, are slated for completion in 2003 and 2007, respectively. Realistically. more time will likely be needed to fully implement the programs. including a 10 year evaluation period following the completion of the programs. spent on the Upper Colorado River Recovery Imple- mentation Program. Within the Lower Basin, conservation eHorts have been underway since 1989 to protect the razorback sucker (and to a lesser degree, the bony tail chub). Lake Mohave holds the largest population of endangered razorbacks in the basin: approximately 35.000 adult fish. The goal is to increase the adult razorback population to 50,000 by the turn of the century through raising fish in captivity until they are large enough to fend off non-native predatory fish. To date. more than 15,000 fish have been returned to the lake and biologists believe nearly 70 percent of them are successfully spawning. Other methods of fish recovery are being imple- mented as well. Dams and reservoirs, which store spring run-off that would normally flow downstream. generally release large amounts of water during the summer to meet downstream water demands, This alteration of the natural hydrograph also impacts native fish which rely on the spring floods to create the warm. nutrient rich wetlands habitat imperative to spawning and the growth of young fish. By altering peak flows (as with Glen Canyon Dam). dam releases can be made to more closely approximate the nalural hydrograph of the river. By removing dikes. seasonally flooded bottomlands can once again be used by fish as an important breeding and growing habitat. lJ. .... 'J ,. ~ ~ ,- a.- lIP RaJiers benefited from rill' crem;on of saud bl'{Jches ill the Grand Canyon during the 1996 artificial j1oOfJ. /~c .~.~.~,." "- .. .... ~ ~ rn-; " ... .--- . ~"" .~ ~ "JI'!ll,"\ >w pi L.:....- -'--.... ~ h -.l.. ""'""""l' 'Y~""; ,_.~ ,,-,;';'M'~.,,'.~. ,~ ~f.~~. ... .. In October 2000, $100 million was appropriated for capital construction costs for these programs, with Efforts also are being taken to $62 million going towards the Upper Colorado, $18 provide fish access to ad. million to the San Juan and $20 million in compen. ditional areas on the sation for dam reoperation in the Upper Basin. Of her Colorado and its program costs will be met through a cost-sharing tributaries that agreement established between the Upper Basin have been states. the Bureau and the Western Area Power blocked Administration (the arm of the Department of Energy b y that handles the power generated on the Colorado River). Projects funded include managing~ instream flows and dam reoperation to ben- , efit endangered fish; habitat restoration.,.~ \. along the river and tributaries; and ... ....... fish ladders, fish screens _ ..... and fish stocking. About $59 million in federal and state funds has already been . .. .... , t 13