FISHERY BULLETIN: VOL. 87, NO. 1 



Figure 3.— Photomicrograph of a transverse section of red drum otolith (sagitta) sampled in May 1986. Ventral is to the left and prox- 

 imal is to the top in this figure. "C" indicates the core of the otolith. Numbers indicate annuli in the region where counts were made. 

 There are 18 annuli and an opaque edge. Bar equals 1 mm. 



by assuming a birth date of early October (Simons 

 and Breuer 1962; Ditty 1986) and annulus forma- 

 tion beginning the winter of the second year. 



Of the 1,726 fish processed, only 94 (5.4%) otoliths 

 were judged unreadable by at least one reader. Of 

 the 58 companion otoliths available from the unread- 

 able fish, only one was judged unreadable. No data 

 were obtained from 36 fish with the first otolith 

 unreadable because their second otoliths were not 

 available. Age estimates, agreed exactly between 

 readers in 95.9% of the samples, were within one 

 year for 99.8% and within two years for 100%. The 

 coefficient of variation for age estimates {V) was 

 0.0058. Exact agreement was improved to 99.5% 

 by recounting sections for which agreement was not 

 initially reached. Readers differed by one year for 

 the remaining 0.5% of samples, and these differ- 

 ences were resolved for all but one sample (not in- 

 cluded in analyses) by counting a section of the other 

 sagitta. 



The oldest female red drum was 36 years (995 mm 

 FL, 1 1 .96 kg) and the oldest male was 37 years (940 



mm FL, 10.49 kg), both captured by hook and line. 

 Ages of offshore schooling red drum captured by 

 purse seine ranged from 1 to 34 years for females 

 and from 2 to 34 years for males. 



There were no significant differences between 

 male and female age distributions in samples taken 

 by purse seine (P > 0.20). Age distributions were 

 grouped by year of capture (October through Sep- 

 tember for 1985-86 and 1986-87) and compared 

 (Fig. 5). Sufficient samples were not available for 

 1984-85 for comparisons. The 11-14 year age 

 classes dominated the 1985-86 samples and 12-15 

 year old fish dominated in 1986-87. There was an 

 apparent coherence between the age-frequency dis- 

 tributions for the two sample years. Anomalies in 

 the age distribution for 1985-86 lagged one year 

 behind corresponding anomalies for 1986-87. Age 

 distributions differed significantly between the two 

 sample years (P < 0.01); however, there were no 

 significant differences between year of birth distri- 

 butions between sample years (P > 0.20). Therefore, 

 samples were combined for all years to obtain year- 



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