FISHERY BULLETIN: VOL. 85, NO. 1 



Table 4.— Mean back-calculated total length (centimeters) ± 95% confidence intervals at successive annuli for male California scorpion- 

 fish captured off southern California, 1981-83. 



Age No. of 

 group fish 1 



10 



11 



2 



3 



4 



5 



6 



7 



8 



9 

 10 

 11 



Average 



7 



31 



62 



40 



15 



4 



9 



5 



7 



4 



18.1±1.6 



17.3 ±0.8 

 17.2±0.7 

 18.3±0.9 

 16.8±1.2 

 18.2+1.5 

 20.6 ±1.4 

 21.0 ±2,6 

 19.7±2.2 

 18.5+1.8 



17.8 



20.4 ±0.9 

 19.5±0.6 

 19.8±0.7 

 20.7 ±0.8 

 19.9±1.2 

 20.3 ±1 

 22.7±1 

 22.9 ±2 

 21 .2 ±1 

 20.6+1 



20.2 



21. 2 ±0.6 

 21. 4 ±0.7 

 22.6 + 0.8 

 21.7±1.0 

 21.9±1.3 

 24.0 ±1.8 

 23.9 ±2.3 

 22.9 ±2.0 

 22.7±1.1 



22.0 



22.5 ±0.7 

 23.9 ±0.7 

 22.8 ±0.9 

 24.0 ±1.4 

 25.2 ±1 

 25.2 ±1 

 24.2 ±1 

 24.2+1 



23.3 



24.9 ±0.7 

 24.0 ±0.8 

 25.7 ±1.7 

 26.5±1, 

 26.0 ±1 

 25.2 ±1. 

 25.0 ±1 



24.5 



25.0 ±0.6 



26. 9 ±1.5 



27.6±1, 



27.0±1, 



26.0±1, 



26.5+1, 



26.0 



27.6 ±1 

 28.3 ±1 

 27.9 ±1 

 27.0 ±1 

 27.2+1 



27.7 



29.2 ±1 

 28.5 ±1 

 28.0 ±1 

 27.8 ±1 



28.4 



29.3 ±1.5 

 28.8 ±1.3 

 29.1 ±0.4 



29.1 



29.4 ±1.3 

 29.8 ±0.6 



29.5 



30,5 ±0.6 

 30.6 



Table 5.— Mean back-calculated total length (centimeters) ± 95% confidence intervals at successive annuli for female California scorpion- 

 fish captured off southern California, 1981-83. 



Age No. of 

 group fish 



1 



10 



11 



2 



3 



4 



5 



6 



7 



8 



9 

 10 

 11 



Average 



3 



31 



43 



31 



24 



11 



3 



1 



2 



1 



17.5±0.8 



17.3±0.7 



17.7±0.6 



19.0±1.0 



19.1 ±1.1 



19.1±1.6 



15.1 ±4.2 



14.9 



20.8 ±5.0 



21.8 



18.2 



20.6 ±1.2 

 20.2 ±0.7 

 20.5 ±0.7 

 21. 8 ±1.0 

 22.0 ±1.0 

 21. 8 ±1.8 

 21.0±2.0 

 23.4 



24.8 ±0.7 

 26.6 



21.2 



22.5 ±0.7 



22.8 ±0.8 

 24,0±1.1 

 24.5 ±1.0 



23.9 ±1.8 

 23.0 ±2.8 

 26.5 



26.4 ±0.3 

 29.5 



23.3 



24.2 ±0.8 

 25. 7 ±1.2 

 26.2 ±1.0 

 25.5±1.6 

 24,6±2.1 

 28.7 



28.0±1.1 

 32.0 



25.3 



26.8 ±1.3 



27.7 ±0.9 



26.9 ±1.6 



25.8 ±1.5 

 30.8 



30.3±1.6 

 33.4 



27.5 



28.7 ±1.0 

 28.2 ±1.6 

 27.6 ±0.8 

 32.4 



31.2±2.1 

 34.4 



28.9 



29.4 ±1.6 



28.9±0.2 



32.9 



32.6±3.0 



34.9 



30.4 



29.7±0.1 

 34.0 



33.1 ±3.0 

 35.5 



31.9 



34.5 



33.9 ±2.7 

 36.3 



34.5 



35.1 ±2.4 

 36.8 



35.4 



37.3 

 37.3 



All three methods of assessing age and growth 

 (direct observations, back calculations, and von Ber- 

 talanffy estimates) yielded roughly similar results, 

 though the method using back-calculated lengths 

 tended to yield faster growth rates than the other 

 two measures, at least for the smaller size classes. 

 Mean lengths at age for females and males were 

 similar through about age 2. Females outgrew males 

 beginning at age 3, when about all males and ap- 

 proximately 60% of females were mature. The max- 

 imum theoretical length for California scorpionfish 

 is 44.3 cm (Table 3), close to the maximum observed 

 length of 43 cm (Eschmeyer et al. 1983). 



Length-Weight Relationships 



A total of 656 males and 371 females from south- 

 ern California were weighed and measured. The 

 relationship between total length and weight fit the 

 relationship W = aL\ where W = weight in 

 grams, L = total length in centimeters, and a and 

 b are constants, with values determined using logjo 

 transformation and fitting the values to a straight 

 line by least squares (Figs. 6, 7). Males tended to 

 be heavier at a given length (ANOVA, F = 14.35, 



P < 0.001). To test whether this difference was an 

 artifact caused by seasonal and gender-related fac- 

 tors, we subtracted gonad weight from body weight, 

 generated the length-weight relationship for each 

 sex, and tested these between sexes. Again, differ- 

 ences between sexes existed (ANOVA, F = 15.68, 

 P < 0.001). 



Condition Factor 



Both male and female California scorpionfish dis- 

 played differences in condition factor between 

 spawning and resting seasons (Table 6). In both 

 sexes, fish were less robust during the spawning 

 season, perhaps because energy normally utilized for 

 somatic maintenance and growth was shifted to egg 

 and sperm production and spawning behavior. Male 

 California scorpionfish were more robust than 

 females during all seasons. 



Maturation and Reproduction 



Although a few fish of both sexes matured at 1 

 yr (14-16 cm TL), over 50% of the males were 

 mature by 17 cm TL and over 50% of the females 



106 



