Hood and Johnson: Life history of Pagivs pagrus 



731 



October 

 n=25 



50 



J 



January 

 fj=40 



n=18 



>- 300 



2 50 



J: 



— I — I — r— 



PG CA VO MA ABPOF 

 November 



I T ~ T T T T I 



July 

 /?=46 



250 



J 



PG CA VO MA ABPOF 



February 

 n=29 



300 



)00 



50 



T — I 



PG CA VO IVIA AB POF 



December 

 n=30 



J 



PG CA VO MA ABPOF 



May 

 n=36 



/ m 50/ I 50/ I 



- f f T I T I I ° 1 " t I Tf I ° 1 T I I I f I I 



PG CA VO MA ABPOF 



J 



t/™ December 25° 3/B Ma;ch ^°° "!/■ 



/y n=30 // n=32 // 



/  ^°1 1 'n I 



" " I 1 T T I ° I " I T T I I I ° I T 



T 

 PG CA VO MA ABPOF 



June 



— I — I — I — \ — I 



PG CA VO MA ABPOF 



August 

 n=30 



300 



n^J 



1 — I — r"T- 



1 I 1 I I I 



PG CA VO MA ABPOF 



I September 



n=14 



PG CA VO MA ABPOF 



PG CA VO MA ABPOF 



PG CA VO MA ABPOF 



I I I T I 



PG CA VO MA ABPOF 



Oocyte developmental stage 



Figure 5 



Average frequency of occurrence of oocyte developmental stages by month for red porgy from the eastern Gulf of Mexico. 

 PG = primary gi-owth oocyte, CA = cortical alveolar oocyte, VO = vitellogenic oocyte, MA = mature oocyte, AB = atretic body, and 

 POF = postovulatory follicle. 



tion of the oxytetracycline mark was consistent with the 

 annual formation of the opaque zone. 



We confirmed that red porgy are moderately long-lived 

 fish (Manooch and Hassler, 1978). The oldest individual we 

 aged was 17 years old, a year younger than the sectioned- 

 otolith-based maximum age of 18 years reported for red 

 porgy in the SAB (Vaughan-^). Nelson (1988) reported the 

 maximum scale-based age for this species in the GOM 

 was 6 years and suggested that the reason for the lower 

 maximum age than that found in the SAB ( 15 years 

 by Manooch and Huntsman. 1977) was that older fish 

 had been eliminated through higher rates of mortality. 

 He reported that mortality rates in the western GOM 

 (Z=0.86/yri were much higher than those in the SAB 

 (Z=0.44/yr; Manooch and Huntsman, 1977). However, this 

 argument is circular because Nelson (1988) estimated 

 mortality from catch curves that had been based on the 

 age structure of the fish he sampled. If his age distribution 

 was truncated owing to sampling or aging bias, then his 



estimates of mortality would have been higher than the 

 true rate. Nelson's (1988) sample size was small (n = \2Q) 

 and geographically restricted (Flower Garden Banks off 

 Texas) compared with the sample size of Manooch and 

 Huntsman (1977), which was large (« = 1777) and from a 

 broad geographic region (SAB). 



Our observed and predicted lengths at age were lower 

 than those reported by Nelson (1988) for the Flower 

 Garden off Texas. It is difficult to assess why our obsei-ved 

 and predicted lengths at age were lower, but the limited 

 sample size of Nelson (1988) (;) = 126) may not be repre- 

 sentative of the GOM population. Other factors that may 

 contribute to these differences include regional differences 

 in growth within the GOM, depth of capture, hook size, 

 or biases between the aging structures. However, Good- 

 year and Thompson^ reported that the depths where red 

 porgy were most commonly captured by GOM fisheries 

 overlapped the depth range in which most of the fish sam- 

 pled by Nelson ( 1988) were captured (60-90 m). Hook size 



