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<br />.
<br />
<br />susgest, but of course not guarantee, a greater concentration of inverte-
<br />brates. The time at year for both samples uas approximately the swae.
<br />The ra.te of decrease ~ orgonis~ r.t Gj?11t 1.buuta1n 15 approximately 35
<br />per cent, at Echo Park 86 per cent, and 74 per cent at Lodore. There
<br />were no comparable data for Island Park in 1961. It is obv1ous that
<br />the upstream pollution of the Green River seriously reduced the numbers
<br />of aquatic fish food organisms within Dinosaur National ~nument.
<br />Invertebrates uill recover more rapidly than the vertebrate forms. It
<br />is sincerely hoped. that a genetic pool of the rare forms of both still
<br />remains. .
<br />
<br />TABIE 3. COMPARISON OF FISH SPECIES AS COLLECTED AT FIVE STATIONS IN
<br />DINOSAUR NATIONALIDNUMENl', OCTOBEB 1961 and 1962.
<br />
<br />Species Station Location*
<br />(Common names) 1961. 1962
<br />Flannel-mouth sucker 1, 2, 3, 4, 5 1, 2, 3, 4
<br />ROlmdtall chub 1, 2, 3, 4, 5 1, 3, 4
<br />Humpback chub 3 4 .
<br />Bluehead Mtn. sucker 1, 2, 3, 5
<br />Colo. mottled sculpin 1, 3, 4.. 5 4
<br />Green slmfish 4
<br />Utah sUversides minnow 1, 2.. 3, 4, 5 1
<br />Green River Spring dace 1, 2, 3, 4, 5 1, 2, 3, 4
<br />Colo. River squawfish 1, 2, 3, 4, 5 1
<br />Carp 1, 2, 3, 4, 5 1, 2, 4
<br />Channel catfish 1, 2, '3, 4, 5 1, 2, 4
<br />Black bullhead 1, 2" 3 1
<br />Fathead minnm., 1** 3
<br />
<br />TABLE 4. COMPARISON OF INVERTEBRATES 'COLLECTED AT FOUR STATIONS m THE
<br />GREEN RIVER IN OCTOBER 1961 AND 1962.
<br />Lodore Echo Park Split Mtn.
<br />Order 1961- '62 1961-'62 1961- '62
<br />
<br />Coleoptera 0.0 0.0 0.1 0.0 0.0 0.0
<br />Diptera 12.0 4.1 0.3 1.5 4.5 4.5
<br />Ephemerida 9.0.5 9.8 0.3 8.0 4.3
<br />Hemiptera 0.0 0.0 0~1 0.0 1.5 2.0
<br />Odonata 0.4 0.5 0.2 0.0 0.0 0.0
<br />P1ecoptera 1.5 0.3 1.5 0.0 4.5 0.1
<br />Trichcptera 0.0 0.0 0.0 0.0 0.0 0.5
<br />Averaee number
<br />of invertebrate
<br />per square
<br />toot 22.9 6.0 12.6 1.8 18.5 12.0
<br />*No data were available for Island Park in 1961
<br />
<br />*1 Split M:llmtain Gor~e
<br />2 Island Park
<br />3 Echo Park
<br />4. Mantle Ranch" Castle Park (Yanwa River)
<br />5 . Gates of Lodore
<br />**7. Beaver Creek, North of the r.t>nument
<br />
<br />~10-
<br />
<br />Island Park
<br />1962*
<br />
<br />0.0
<br />20.5
<br />8.0
<br />0.5
<br />0.2
<br />0.0
<br />1.3
<br />
<br />30.5
<br />
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