GRIMES ET AL.: REPRODUCTIVE BIOLOGY OF TILEFISH 



Table 1— Mean (X) and sample size (A/) for predorsal adiposal 

 flap height at size and age for male and female tilefish, and 

 students Mests of flap height differences between sexes. 



Males Fem ales 



X(mm) N X(mm) N 



(-value 



Proba- 

 bility 



Size 



(FL, mm) 



45-49 

 50-54 

 55-59 

 60-64 

 65-69 

 70-74 

 75-79 

 80-84 

 85-89 

 90-94 

 95-99 

 100-104 



Age 

 (years) 



3 

 4 

 5 

 6 



7 



8 



9 

 10 

 11 

 12 

 14 

 15 



20.1 

 23.1 

 25.7 

 30.6 

 37.1 

 49.8 

 61.8 

 72.3 

 82.4 

 68.0 

 63.0 

 98.0 



20.5 

 36.2 

 33.2 

 44.0 

 51.4 

 57.4 

 65.0 



112 



13 



29 



36 



40 



73 



67 



30 



30 



12 



1 



1 



8 











6 



23 



41 



40 



17 



8 



4 











1 



17.1 

 23.6 

 25.9 

 27.6 

 31.6 

 31.7 

 37.6 

 37.7 

 28.8 

 38.5 



5.0 

 8.1 

 20.4 

 21.6 

 27.9 

 30.1 

 30.4 

 32.9 

 31.9 

 30.9 

 36.5 

 36.8 



19 



49 



62 



105 



101 



51 



25 



11 



8 



2 











6 



7 



16 



32 



51 



42 



40 



35 



16 



9 



2 



14 



1.02 



0.33 



0.04 



0.91 



2.63 



3.58 



4.05 



1.90 



1.84 

 Not testable 

 Not testable 

 Not testable 



Not testable 

 Not testable 



0.018 



6.63 



3.42 



5.64 



5.97 



5.45 



5.59 

 Not testable 

 Not testable 

 Not testable 



N.S. 



N.S. 



N.S. 



N.S. 



<0.01 



<0.01 



<0.01 



<0.05 



<0.05 



N.S. 



<0.001 



<0.01 



<0.001 



<0.001 



<0.001 



<0.001 



histological data pooled over all years of the study. 

 The two methods gave substantially different results 

 for males; however, both visual and histological data 

 suggested that all females matured at 60-65 cm FL 

 and 8-9 years of age (Figs. 2, 3). Visual staging in- 

 dicated that virtually all males were mature at 80-85 

 cm FL and 10-11 years. In contrast, histological 

 results indicated almost all males were mature at 

 65-70 cm FL (estimated age 7-8 years, Turner et 

 al. 1983) (Figs. 2, 3). That is, visual staging sug- 

 gested that females matured about 20 cm smaller 

 and 2-3 years younger than males; however, accord- 

 ing to histological analysis, both males and females 

 were mature and producing gametes at a similar size 

 (60-70 cm FL). Thus, these results show that al- 

 though males were producing sperm at 65-70 cm 

 FL (estimated 7-8 years, Turner et al. 1983), they 

 were not developing a large testicular mass until 

 80-85 cm FL and age 10-11 years. 



We reasoned that predorsal adipose flap size 

 might be a sign of maturity or reproductive status 

 of males, because the height of the flap was larger 

 in males than females above 65 cm and age 5 years 

 (see previous section on Sexual Dimorphism). Addi- 



tionally, the development of enlarged adipose flaps 

 in males coincided with the size of 50% maturity 

 (60-65 cm FL) as judged by development of enlarged 

 testes (i.e., visual method), not at the smaller size 

 of 50% maturity (50-55 cm FL) determined his- 

 tologically (Fig. 2). Therefore, if predorsal adipose 

 flap height were a sign of reproductive status in 

 males, then mature males should have larger flaps 

 than immature males; and this was so (Fig. 4). 

 Furthermore, ANCOVA (with FL as the covariate) 

 indicated that flap height was significantly larger 

 in mature males than immature males (Table 2). 



Table 2. — Mean and ANCOVA (with FL as the covariate) of predor- 

 sal adipose flap height in sexually mature and immature male 

 tilefish. Flap height data set tested was restricted to a size range 

 containing both mature and immature males (50-75 cm FL). df 

 = degrees of freedom, ss = sum of squares, W = sample size, and 

 X = mean. 



Maturity 



FL 



FL X maturity 



Error 



Total 



1 



1 



1 



177 



180 



504.4 



7,423.4 



605.1 



13,895.7 



30,365.8 



6.42 



94.56 

 7.71 



0.0121 



0.0001 

 0.0061 



Because we had studied reproduction during a 

 period of rapid expansion of the fishery, i.e., the 

 commercial longline fishery had decreased the 

 tilefish population by one-half to two-thirds from 

 1978 to 1982 (Turner 1986), we decided to examine 

 the data to determine if the fishery had affected the 

 size at which tilefish were developing enlarged 

 testes (i.e., attaining maturity as assessed by the 

 visual method). A comparison of visually assessed 

 sexual maturity at size and age for 1978 and 1982 

 suggested that females <50 cm FL were maturing 

 at a smaller size in 1978 than in 1982, but that 

 females >50 cm FL matured at very slightly larger 

 sizes in 1978 than in 1982 (Table 3). Log-likelihood 

 contingency tests of these data for females indicated 

 that maturity-at-length was significantly different 

 in 1978 and 1982, but the difference was due to the 

 numbers of mature and immature fish between 41 

 and 55 cm (Table 3). The data for males <75 cm FL 

 indicated that males matured at smaller size in 1982 

 than in 1978 (Table 4). A log-likelihood contingency 



749 



