|
<br />
<br />Colorado River endangered fish
<br />
<br />
<br />Colorado squawfish (Ptychochei/us lucius)
<br />North America's largest minno..... Colorado
<br />squawfish once grew to ncarly 6 fCC'1 long and were
<br />called "white salmon" or "Colorado salmon" by
<br />early settlers. Historically. these \oracious predators
<br />dominated the Colorado River system.
<br />
<br />Razorback sucker (Xyrauchen texanus)
<br />Razorback. suckers can gruw 10 more than J feet
<br />and are one of the largest suckers in Nonh America.
<br />Few if any young razorback... are left in the wild.
<br />
<br />Bonytail chub (Gila eJegans)
<br />Bony tail chubs can gro.... to 2~ inches or more
<br />and can liw nearly 50 years. Wild bony tails arc
<br />nearly extinct.
<br />
<br />Humpback chub (Gila cypha)
<br />The pronounced hump behind ih head gives the
<br />humpback chub a ..trildng. unusual appearance. This
<br />minnow can g.row to nearly 20 inche~ and may
<br />survive more than 30 years.
<br />
<br />~ \COlORA.OO
<br />SOUA.Wf'S'"
<br />,
<br />,
<br />'""-..."'....,.....
<br />
<br />'~
<br />' '
<br />, .@ l'lOU"D1A.'l
<br />CKUB
<br />,
<br />, ,
<br />-"".,,,,~,.....
<br />
<br />\nj.!k,-.. ma.\ ("nfu..... ~tlung ('uloradu ....IUa"fhh "ilh
<br />rnumltail rhuh... lht, "f~ dilTt'rl'nn' i, Ih.t1lht'r"undtail',
<br />muuth nlrnd'jll,1 tu Iht. fronl of lht' t'~r. rht, '11<lut nf,h..
<br />"(Ju;l"fhh i, Itln~r, and ih Ihid, fnldt'd lip' t"tt'nd In Ih..
<br />n'arnrlht,t'~t'.
<br />
<br />The Colorado River
<br />
<br />The Colorado and its tributarie.. make up one of
<br />the world's, most colorful river syqcms. From the
<br />high mountains of Wyoming and Colomdo. the river
<br />drops more than two miles in elevation on a 1.700-
<br />mile journey to the Gulf of California. For long
<br />..tretches. the rivcr "ys{cm i... bounded by red canyon
<br />\valls. Fluws fluctuate widely from season to season
<br />and year to year. For example. hislOric flows at
<br />Yuma. An?_.. rangt.'d from a few thousand cubic fect
<br />per second to nearly 400.000. It lOok lOugh.
<br />adaptable creaturc,", 10 "urvivc in Ihis riwr systcm.
<br />
<br />Endangered fish distribution map
<br />
<br />
<br />.......,
<br />==':-"';.'.."'C
<br />
<br />."-
<br />
<br />
<br />11
<br />I.
<br />i!
<br />jl
<br />II,
<br />!I
<br />II
<br />
<br />Why are these fish endangered?
<br />
<br />Water
<br />development
<br />Dams and
<br />canals have
<br />been con-
<br />s t I' U C t e d
<br />throughout
<br />the Colorado
<br />Rivcr Basin
<br />to provide
<br />water for power. irrigation and public watcr supplies.
<br />Thcse waleI' projects have restricted the lish to about
<br />25 percenl of their filnge, blocked some spawning
<br />mignllion routes and ~ooled the waleI' immediately
<br />downstream of the dams. Also. many of the ri\-ers'
<br />"backwaters" needed by young: fish have disappeared.
<br />
<br />J)
<br />I,
<br />I,
<br />f!
<br />IiI
<br />hf
<br />
<br />I
<br />I
<br />
<br />Why should anyone care about
<br />saving endangered fish?
<br />
<br />legal basis
<br />B<<'ause these lish are so rare. they are protected by
<br />state laws .md the federal Endangered Species Act. In
<br />passing this act, Congress ....as reflecting the belief
<br />that rare ~pecics should be ~ved whenever possible.
<br />
<br />--
<br />
<br /><o,Q."~
<br />
<br />
<br />Non-native
<br />fish
<br />Sport and
<br />bait fish have
<br />been intro-
<br />duced inlO
<br />rivers. lakes
<br />and reser--
<br />voirs. Non-
<br />native fish
<br />compele ......i'h native fish for food and space and may
<br />prey on the eggs and young of endangered fish. The 14
<br />nathe Colomdo River tish now have to compete .....ith
<br />more than 40 non-native species,
<br />Rainbow. brown and cutthroat trout are slill
<br />stocked in higher e1e\3Iions of the Colorado Ri\'er
<br />and its tributarie:-. Trout prefer colder waters and arc
<br />not considered competiton. with endangered fish.
<br />
<br />.r~
<br />... ..
<br />'-"..,
<br />
<br />1~~1I1Sl'1
<br />
<br />..~~.~.' ui:;.o
<br />." ~.
<br />......,. '-,
<br />-_.~~
<br />--ua" . ,~-;-..::..:
<br />-" """ .--
<br />....., ~...-.
<br />...~, ."", ....--
<br />~o';";!" 'iA.._ -.
<br />.....~- ~~. -
<br />_"--- IIW~
<br />
<br />Other factors
<br />Some native fish may be killed accidentally by
<br />anglen;. And in the mid-I960s, the chemical rotenonc
<br />wa.... used in p<mions of the upper Colorado River
<br />Ba....n to reducc native tj...h numocn; and make way for
<br />non-nati\'c spon fish. But researchers belic\'e this had
<br />no lasting effect on nalh'e fish populations,
<br />Other possible problems include pollution and
<br />parasites. and among chubs. h)'bridization.
<br />
<br />I
<br />
<br />Environmental reasons
<br />Human impact has caused 40 specics and
<br />subspecies of fi"h to go cxtinct in Nonh America this
<br />century, Some biologists theorile that - like the-
<br />coal-miner's canary. whose death forewarns workers
<br />of loxic gases underground - the dedine of Ihese
<br />fi~h may be 3 warning that other nalive species of the
<br />Colorado River ecosystem abo are at risk.
<br />
<br />-
<br />
<br />linn' .Ihundanl in tht. t'lIluradn Ki\t'r Ha,in, Iht"w rhh
<br />II"" art. ruun"unl~ inn'rl<lin p"rti"",,,r..nllwrl\t'r..,
<br />
<br />Release them alive
<br />
<br />If you catch any fish you cannot identify. please
<br />return il to the water alive, If possiblc, lea'..e Ihe fish
<br />in the water while gently removing thc hook. Do not
<br />squeeze the tish or put your tingers in its gills. If the
<br />hook is deeply embedded. cut the line instead of
<br />pulling oul the hook, Hold the fish facing upstream
<br />and slowly mow it forv.-'ard and back in the water.
<br />Then relea..e the fi:-.h in quiet water,
<br />If the fish i.. lagged. please report the tag number
<br />and color to the Colorado Division of Wildlife. (03)
<br />:!4H-7175. or Utah Division of Wildlife Resource".
<br />(801) 538.-4700. Fines up 10 5.100.000 are po....ible
<br />for willfully demoying endangen..'d fhh.
<br />
<br />II
<br />
<br />Sport-fishing
<br />Until the early 1900s, squawfish were the
<br />Colorado Ri\'er's lOp predalor. Anglers were known
<br />to eatch thes.e fish using mice. birds and even small
<br />rabbits a" bili!. If the fish can be recovered,
<br />tomorrow.s anglers may gain the chance to reel in
<br />Colorado squawlish weighing 15 to 20 pounds.
<br />
<br />I-
<br />
<br />Ecosystem balance, scientific benefits
<br />Scientific research has shown Ih:lI losing one
<br />species in an ecosy"tem can cause a chain reaction
<br />affecting a series of other living things. Also. the
<br />species' unique genelic material and potential
<br />medical. industrial and agricultural benefits would
<br />be gone forever.
<br />
<br />Heritage
<br />Colorado squawfi"h and razorback suckers
<br />evolved more- than 3 million years ago. Modem man
<br />has existed only about 100,000 10 250.000 years.
<br />These fish arc pan of the West's heritage and are
<br />found nowhere else in the world.
<br />
<br />Philosophical reasons
<br />As Aldo Leopold. one of the founders of the
<br />conservation mo\'ement. :<.aid. .. ... If the land
<br />mechanism as a whole is good. then eveI") pan is
<br />good, whether we understand il or no! ... ..
<br />
<br />
|