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<br />Figure 60. Flannelmouth sucker, 28,5 em In total length. from the Virgin River, Ari-
<br />zona This species remains common In the upper Colorado River baSin. but has
<br />disappeared enllrely from the lower baSin (including the Gila River drainage)
<br />downstream from Lake Mead,
<br />
<br />mode:raTt. rapids anJ Tlftles In pursuit of bonum-
<br />dwelling in\'t'rtebrJtcs, Jlpt. Jnd ocf.:anlc Jt:bn~.
<br />BlueheaJ moum.lln-suckr-r" (Fl}.;. (1) tend to ftOed on
<br />harder bottoms. scrJplnF alpllllms ,mJ other
<br />ur"L!anJC matt"n.\I~ (Including clinging In\"r-ttchratr-sl
<br />from rocks wjth thelf modified, c;Hnla,l<:lnous Jaws
<br />All three o( the laST speue5. hretJ In sprln~ on tLffle~
<br />
<br />Figure 61. Breeding adults of bluehead mounlaln-sucker.
<br />ca, 450 and 350 em in total length, from the mouth 01 lhe
<br />Pana River. Arizona ThiS species remains abundant Within
<br />its native range In the upper Colorado River baSin.
<br />Photograph by W G Kepner.
<br />
<br />
<br />Canyon-bound reaches of the RIO Yaqui at{'
<br />occuplr-d by roundtJ.il chuhs. Yaqui suckers. and
<br />YaquI uHllshlba,l;"" ,M ).,lqUJ (Fig. 6.h Beautiful
<br />..hlnt"rs and Mexican stonr-rollcrs ll\'e ,dong the b;lnks
<br />J.nd In qUI~ter pIJc~s. It IS notabl~ ht:re that link'
<br />samp1in.l-: has been dOn{' In tht:s~ reaches. which are
<br />mostl.... Is()tued and a((essibit- only by rt....~r. It will
<br />not be slIrptJslng If future clllleccors In the Rio
<br />YJqlli and us major tflr.utilfles discover new species
<br />(If sWltt-\\'Jter tlsht's.
<br />The tlsh communIty of Wldt.r. less dramatic lowt:r
<br />pUtS of the Color ado RI'I-er. most of wluch is now
<br />dry or otht'rwlS~ highly modJllcd. nJnslS[eJ of a
<br />small number of speCl,ll kmds, plus In HS lnwt"rmos[
<br />rC',1(:he5 a f(.w marine spe(lr-s th,1t entr-red from the
<br />Gulf of Cahfocma. Freshwater tlshc's of the lowermtlst
<br />rrach IncluJed Colorado 5quawtlsbhhdr"!I)!f, bony tail!
<br />,-j'dr"IU'J rlt.f,,,,ur. and rJZtlrh.lck suckt"r'lJdr,tkt(
<br />!,mlh"J", all 01 which passr-d a'addy thttmgh canyon
<br />reJcbes, but rarely bn'd tbt"rt". :\11 .l\'.ldable (,'I."ldence
<br />mdlCatt'"s th;ll squawtlsh anJ fdzorback wt:"rt:"
<br />>1r.unJanr .md that b,myud \\,IS common as well,
<br />Fl.tnnelm'luth such'r. wtlundlln. Jnd roundt'1l1 chub
<br />also were rresr-nt, hut .Irt" tcprl:st'"nted by only a few
<br />specimens In early colleulOns and mllst 11d\"e bt"l.'"n
<br />rd;lti,'e1~' rare. Shallow sltlu~hs and b,lckwaters
<br />supported dt:"Sl'f[ puptish. Rl)UnJrad chuh. YaqUI
<br />
<br />3D
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