1 — I — I — I — I — I — I — I — I — I — I — I — I — r 



SOUTH ATLANTIC AREA 



1 — I — I " Ti — r 



1 — I — I — I I I r 



50 100 150 200 250 300 350 400 450 500 550 600 650 700 750 800 850 900 



BODY WEIGHT IN GRAMS 



Figure 8.--Weight composition of samples from purse-seine catches, 1957. 



Average Length and Weight 



The average lengths and weights of 

 fish at each age, by sex, in the 1957 

 catches are given in appendix tables 

 11-15. Summary data for the past 3 

 years (tables 9 and 10) show that fish 

 of the numerically dominant age group 

 in the sunnmer catches in the different 

 areas were shorter, and lighter, on 

 the average, in 1957 than those of the 

 same age in the previous 2 years; 

 however, in all areas this difference 



was restricted almost entirely to fish 

 of ages 1 and 2 (1956 and 1955 year 

 classes respectively). The predomi- 

 nance of these age groups thus was 

 reflected in a reduction in the aver- 

 age size of fish in the summer 

 catches in all areas (last column in 

 tables 9 and 10). Among the middle 

 age groups (ages 3 to 6) there was 

 a tendency for fish to be slightly 

 larger in 1957, although in those age 

 classes represented by adequate num- 

 bers of fish, the difference probably 



15 



