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<br />
<br />Table 3.8
<br />
<br />Survival and growth of Colorado pikeminnow larvae produced by adults
<br />exposed to selenium in the diet and water for 154 days prior to spawning
<br />Source: Buhl and Hamilton 2000).
<br />
<br />
<br />Diet Water Female Swimup Total Weight
<br />(I'g/g Day 10 Day 30 Length K' N
<br />) (1'9/L) ID (Day 5) (mm) (mg)
<br />2,18 0.15 1A-2 100 83,3 80,0 20.1 55,3 0.68 44
<br />(1,1) (7,1) (0.06)
<br />2.18 5,74 2A-10 98,3 98,3 95,0 19.6 53,3 0,71 51
<br />(1,1) (6.9) (0,08)
<br />7.28 1,21 3A-20 100 96,7 93,3 19.7 50,6 0.65 53
<br />(1.4) (9,1) (0.06)
<br />7.28 1,02 3B-22 95,0 93,3 91,7 19.6 53,2 0.70 52
<br />(1,3) (7.6) (0,07)
<br />7.28 1,62 3C-26 88,3 85,0 85,0 19.4 51,1 0,69 47
<br />(1,0) (7.8) (0,06)
<br />7.28 5,95 4A-29 98,3 93,3 90.0 20,0 54,3 0,68 52
<br />(0,8) (7.2) (0,05)
<br />7,28 5,82 4B-31 97,5 97,5 97.5 20,2 56,1 0,68 37
<br />(0,9) (7.0) (0,05)
<br />11,83 2,38 5A-38 100 78.3 78.3 19,9 52.1 0,66 45
<br />(0,9) (6,7) (0,05)
<br />11,83 1,63 5B-41 98,8 78,3 73,3 20,3 58.8 0,70 39
<br />(1.1) (9,3) (0,06)
<br />11.83 8.12 6B-50 95.0 86,7 85,0 19,8 52,6 0,68 42
<br />(1.1) (8,0) (0,06)
<br />a Mean measured concentrations in exposure tank with diet concentrations based on dry weight.
<br />b Mean and SD in parentheses.
<br />e Condition factor.
<br />
<br />In sununary, investigations by the SJRlP showed that some contaminant issues occurred in the San Juan
<br />River Basin, but they tended to be limited to irrigation drainage areas. It is also possible that contaminants
<br />were more prevalent during low-flow periods. It is doubtful that any of the populations of native fishes
<br />studied during the 7 -year research period were limited by contaminants. However, this does not mean that
<br />contaminants were not a major limiting factor at some time in the past, when safeguards were not as
<br />prevalent as they are today,
<br />
<br />September 2000
<br />
<br />3-56
<br />
<br />Program Evaluation Report
<br />
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