7772

• UCREFRP Catalog Number: 7772
• Author: Bestgen, K. R. and M. A. Williams.
• Title: Effects of Fluctuating and Constant Temperatures on Early Development and Survival of Colorado Squawfish.
• USFW Year: 1994.
• USFW - Doc Type: Fort Collins, Colorado.
• Copyright Material: NO

Table 1.--Percent hatch and survival, and early development (mean and SE; N = 4 replicates) of Colorado squawfish reared at four constant and three
diet fluctuating (+ 2.5°C) temperatures.
Nominal temperature and regimen
18°C 22°C 26°C 30°Cb
Biological variables Constant Fluctuating Constant Fluctuating Constant Fluctuating Constant
Mean percent hatch 79(2.5) 65(5.0) 60(7.8) 74(8.7) 69(4.8) 54(10.5) 38(6.5)
Mean percent survival to
7 d posthatch 52(4.5) 83(4.3) 58(5.8) 69(7.9) 78(4.1) 88(4.9) 13(4.4)
Mean percent abnormal` 15(7.5) 10(3.6) 14(2.5) 22(6.3) 2(2.6) 6(3.0) 100
Mean time (h) to:
Initiation of hatchings 110(8.1) 124(9:7) 81(5.7) 97(1.3) 77(1.6) 75(0.3) Sg
50% hatchings 134(2.3) 144(0.5) 1 IS(5.4) 105(2.0) 96(0.5) 98(1.0) 68
End of hatchings 154(6.8) 152(4.8) 134(13.0) 128(4.8) 110(4.8) 111(4.9) gl
Hatching interval (h)e 44 28 53 31 33 36 23
Inflation of air bladderf 186 172 183 143 139 141
First feedingf 229 194 183 167 163 122
Mean total length (mm) at:
Hatching (N=10) 4.8(0.3) 5.2(0.2) 5.3(0.1) 5.6(0.2) 5.5(0.2) 5.5(0.2)
7 d posthatching (N=10) 9.7(0.1) 9.8(0. l) 9.6(0.2) 10.2(0.1) 10.0(0.1) 10.0(0.1)
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