those of S.flavidus and S. pinniger at equivalent 

 lengths (Gunderson et al. 1980). The mean value 

 of weight-specific fecundity (389 eggs/g body 

 weight) is also relatively high for this genus, as 

 summarized by MacGregor (1970); this value 

 should be considered carefully, however, since 

 weight-specific fecundity is dependent upon size 

 and age (Table 1). 



Table 1.— Weight-specific fecun- 

 dity (eggs/g body weight) by age 

 class of Sebastes entomelas from the 

 present study. N- number of speci- 

 mens, SE = standard error of the 

 mean. The mean age of specimens 

 >15 yr is 21.5 yr. 



The length-fecundity and weight-fecundity re- 

 lationships described in the present study differ 

 significantly from data presented by Phillips 

 (1964; analysis of covariance, P<0.01). The 20 

 fish in his study were collected from 1957 to 

 1959 in California. We converted the total length 

 measurements in Phillips to fork length using 

 the total length-fork length relationship in Len- 

 arz 4 and plotted mean values by 1 cm length in- 

 tervals for comparison with data from the 

 present study (Fig. 2). Values are similar through 

 approximately 40 cm FL, but at greater lengths 

 the values from Phillips are more variable and 

 generally lower than fecundity determined in 

 the present study. Similarly, data on mean 

 weight-specific fecundity was lower; MacGregor 

 (1970) calculated a value of 288 eggs/g from Phil- 

 lips' (1964) data. As stated above, the mean from 

 the present study was 389 eggs/g. The weight- 

 fecundity regression from Phillips(1964)ischar- 

 acterized by a lower slope. The lines intersect 

 near 1,000 g and Phillips' estimate at 2,000 g is 



67.5% of that predicted by the regression from 

 the present study. Gunderson et al. (1980) noted a 

 similar pattern of generally lower fecundity at 

 greater lengths when comparing their data for 

 S. goodei and S. flavidus with that of Phillips 

 (1964). Since the methods in the present study 

 are most similar to those of Gunderson et al. 

 (1980), methodological differences could explain 

 the different results. Geographic differences, 

 however, may also be involved. Gunderson et al. 

 (1980) noted increased fecundity at length for S. 

 goodei in northern as compared with southern 

 geographic regions. Clear differences are also 

 apparent in the length at 50% maturity for sev- 

 eral species of Sebastes, with maturity occurring 

 earlier in southern areas. Barss and Echeverria 

 (footnote 3), for example, noted that the length 

 and age at 50% maturity for S. entomelas females 

 are 38 cm FL and 7 yr off Oregon and 32 cm FL 

 and 5 yr off California. Thus reproductive char- 

 acteristics within species may differ between 

 areas. 



It is probable that & entomelas spawns only 

 once per year. While MacGregor (1970) noted 

 evidence of multiple spawning in three species of 

 Sebastes, these species were generally character- 

 ized by lower weight-specific fecundity than ob- 

 served for S. entomelas. Furthermore, the lack of 

 a secondary mode of oocytes and the distinct, 

 relatively short spawning season noted by Barss 

 and Echeverria (footnote 3) in both Oregon and 

 California samples indicate a single spawning 

 per year for this species. 



Estimates of fecundity from the four samples 

 of S. entomelas with fertilized ovaries were be- 

 low values predicted from the weight-fecundity 

 relationship; the percent of expected fecundity 

 decreased with increasing developmental stage 

 of embryo (Table 2). These specimens had no 

 signs of extrusion of embryos during capture, 

 but it cannot be ruled out. Raitt and Hall (1967), 

 however, noted that egg counts from fertilized 



Table 2.— Percentage of nonviable eggs and reduc- 

 tion in fecundity in the ovaries of four specimens of 

 fertilized Sebastes entomelas. The percent non- 

 viable eggs was determined in four subsamples of 

 300 eggs. Expected fecundity was determined from 

 the weight-fecundity relationship. 



4 Lenarz, W. H. 1980. Aging and growth of widow rock- 

 fish. Unpubl. manuscr. Southwest Fisheries Center Tibu- 

 ron Laboratory, National Marine Fisheries Service, NOAA, 

 Tiburon, CA 94920. 



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