HOUDE and LUBBERS: SURVIVAL AND GROWTH OF STRIPED BASS 



Table 3.— Linear regressions describing growth in length and exponential 

 regressions describing growth in weight of striped bass (SB), striped bass x 

 white bass (WBX), and striped bass x white perch (WPX) during the period 

 6-30 d after hatching. In the linear regression, / is standard length in mm, t 

 equals days after hatching, b equals growth rate in mm, and a is the y-axis 

 intercept. In the exponential regressions, W is wet weight in mg, f equals days 

 after hatching, G is the instantaneous growth coefficient, and W is the 

 theoretical weight in mg at time zero. 



Larvae and 



experiment 



number 



Artemia 

 concentration 

 (number L~ 1 ) 



LENGTH 



Equation 



/ = a + bt 



Standard 

 error 

 of b 



'Differ significantly from SB-1 and SB-2, P< 0.01. 

 comparison procedure. 



ANCOVA followed by SNK multiple 



The mean instantaneous mortality rates during 

 the 9-30 d after hatching ranged from 0.0601 to 

 0.0713 d-\ equivalent to 5.8 to 6.9% d" 1 (Table 

 4B). Cannibalism probably occurred during the last 

 10 d of the experiment. Some large survivors had 

 small larvae in their stomachs when the experiments 

 ended. 



Size-at-Age 



When larvae were stocked in the enclosures at 9 

 d after hatching, white bass hybrid larvae were 

 significantly heavier (ANOVA, P < 0.01) and slight- 

 ly, but not significantly, longer than white perch 

 hybrid and striped bass larvae (Table 4A). Because 

 all larvae had been fed Artemia nauplii in the hatch- 

 ery for 3 d prior to stocking it is not known if the 

 sizes at stocking reflect the relative weights and 

 lengths of the three kinds of larvae before they 

 began to feed. 



At 30 d after hatching mean lengths of striped 



bass and hybrid larvae from the enclosures ranged 

 from 12.58 to 12.96 mm SL (Table 4C). Mean wet 

 weights ranged from 38.38 to 43.28 mg (Table 4C). 

 There were no significant differences in mean 

 lengths or weights among the three types of larvae 

 or among the nine enclosures (ANOVA, P > 0.25). 



Growth Rates 



Mean rates of growth in length for the striped bass 

 and hybrid larvae ranged from 0.30 to 0.32 mm d _1 

 (Table 4D; Fig. 3). There were no significant differ- 

 ences in the rates among types of larvae or among 

 replicate enclosures (ANCOVA, P > 0.10). 



The common, instantaneous rates of growth in 

 weight were 0.1444 for striped bass (= 15.5% d _1 ), 

 0.1650 for white bass hybrids (= 17.9% d" 1 ) and 

 0.1593 for white perch hybrids (= 17.3% d" 1 ). The 

 rates of growth (Table 4E; Fig. 4) differed signifi- 

 cantly among the three types of larvae (ANCOVA, 

 P < 0.05) but not among enclosures (P > 0.10). The 



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