FISHERY BULLETIN: VOL. 85, NO, 1 



0.65-0.70 mm long, any were "left behind" and'not 

 spawned with the ripening batch. 



For 248 fish which either had a clearly defined and 

 separated advanced mode of unhydrated oocytes or 

 carried hydrated ova with a clearly defined and 

 separated next mode, the largest (LMX or NMX) 

 and median-sized (LMD or NMD) oocyte in the mode 

 were significantly correlated (r = 0.94, P < 0.01), 

 and the slope of the Model II regression was nearly 

 1 (1.042). The correlation was essentially unchanged 

 by addition of data from 51 more fish where the 

 median size of an incompletely separated mode was 

 only estimated. These results indicate that, even if 

 a mode is incompletely separated, the estimated 

 LMD is a useful parameter and, furthermore, that 

 for purposes of comparing different fish, LMX is as 

 appropriate an indicator of size of oocytes in a mode 

 as LMD. Consequently, in subsequent analyses of 

 LMD data both unequivocal and estimated values 

 were used, and in other cases LMX was used to 

 analyze change in oocyte size during ripening. Both 

 decisions were made primarily to include data from 

 specimens with small oocytes and without complete- 

 ly or even partially separated modes. 



Fecundity 



Fecundity of 222 females 35-58 mm SL ranged 

 from <100 to >1,600, and relative fecundity ranged 

 from 432 to 4,098 eggs/gram. Although low relative 

 fecundities were observed in samples from almost 

 all months, most values over 2,000 were from fish 

 taken in summer and fall (Fig. 1); consequently, the 

 fecundity data from "winter" (November through 

 April) and "summer" (May through October) fish 

 were treated separately for all subsequent analyses. 

 There were no significant differences in size com- 

 position between the summer and winter specimens 

 (Kolmogorov-Smirnov test, P > 0.20). The mean 

 relative fecundity for winter (1,363, n = 93, range 



= 496-2,763) was significantly different (P < 0.01, 

 i-test) from that for summer (2,097, n = 128, range 

 = 433-4,099). Regressions between fecundity and 

 length or weight (Table 1) also indicated that winter 

 fish were less fecund than summer fish. 



When relative fecundity data for each season were 

 partitioned according to LMD (<0.65 mm, 0.65-0.75 

 mm, and >0.75 mm), there were no significant dif- 

 ferences between groups in the summer data (anal- 

 ysis of variance, P > 0.05), but there were signifi- 

 cant differences in the winter data (P < 0.001). 

 Inspection of the data indicated that the latter was 

 due mostly to low values for the fish with LMD 

 <0.65 mm. This could result from incomplete re- 

 cruitment of oocytes to modes barely separated from 

 smaller oocytes. There were, however, only 12 fish 

 in this category, and the small sample size plus the 

 absence of similar evidence in summer fish indicates 



7 4 

 o 



X 



U) 



3- 



O) 



>- 

 I— 



O 2 



Z 



Z) 



> 



< 



LU 

 OH 



I • 



;«• 



I 



i t 



j'f'm'a'm'j'j'a's'o'n'd' 



MONTH 



Figure 1.— Relative fecundity in thousands of eggs/g ovary-free 

 dry weight vs. date of collection for 222 nehu from Kaneohe Bay, 

 HI. 



Table 1 .—Summary of Model II regression statistics for relationships between length and w^eight and between fecundity 

 and size based on data from 128 "summer" and 94 "winter" nehu plus relationship between gonad weight and 

 bodily weight for 67 summer and 44 winter nehu with hydrated ova. Variables are standard length in mm (SL), ovary- 

 free bodily dry weight (S) and total dry ovary weight (G) in g, and fecundity in numbers of ova in the most advanced 

 mode (F). Results of regressions based on natural logarithms are given as power curves (antilog form). The 95% 

 confidence limits are given for either the slopes of linear equations or the exponents of power curves. 



X.Y 



Summer 



(95% CL) 



Winter 



(95% CL) 



In SL, In S S = 8.868 x 10"' SL 



3.25 



n F 



SL, F 

 In SL, 

 S, F 



In S, In F 

 In S, In G 



F 



F 

 F 

 F 

 G 



= -2352 + 63.1 SL 

 = 6.073 X 10"^ SL^^^ 

 = -351 + 3787 S 

 = 7094 S^^^ 

 = 0.2339 S'^^ 



(3.11-3.40) 0.94 S = 3.696 x 10"^ SL 



3.47 



(56.3-70.6) 

 (5.24-6.75) 

 (3,420-4,194) 

 (1.63-2.05) 

 (1.65-2.14) 



0.59 

 0.49 

 0.66 

 0.56 

 0.72 



F 

 F 

 F 

 F 

 G 



-1465 + 38.9 SL 

 1.226 X 10'^ SL^^"* 

 - 223 + 2444 8 

 4,538 S' ^° 

 0.1192 S'^' 



(3.30-3.65) 0.94 



(33.6-45.0) 

 (5.45-7.15) 

 (2,119-2,819) 

 (1.57-2.05) 

 (1.32-1.95) 



0.51 

 0.56 

 0.53 

 0.59 

 0.60 



130 



