FISHERY BULLETIN: VOL. 83, NO. 4 



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IMMIGRATION TIME 



Figure 5.— Age (mean + 1 standard error) and standard length (mean ± 1 standard error) of late-larval spot entering 

 the Newport River estuary in North Carolina, December 1979-April 1980. The numbers offish measured and aged 

 at each sampling date are in parentheses. 



both groups was identical (22 December 1979), the 

 variance about the mean was greater for Inlet- 

 caught fish. Consequently, back-calculated lengths 

 also were more variable for Inlet-caught fish {F-test, 

 P < 0.05), but on the average they appeared to be 

 larger at every age (^test corrected for unequal 

 variance, P < 0.05). 



Significant differences were found for the weight- 

 length relation (Fig. 7) of laboratory-reared larvae 



<6 mm and those >6 mm (ANCOVA, P < 0.001). We 

 selected 6 mm as the dividing point because basic 

 changes in body form had been observed to occur 

 at around 6 mm (Powell and Gordy 1980). The length 

 exponent for spot <6 mm SL (4.201) was close to 

 the mean value (4.152) reported by Laurence (1979) 

 for larvae of seven marine fishes, while larvae > 6 

 mm (3.282) approached isometric growth (Ricker 

 1975). 



594 



