The lengths of fish caught in the South 

 Atlantic Area ranged from 110 to 240 mm. 

 Age-2 fish furnished the principal modal 

 group and showed greater variation than any 

 other age group, ranging from 125 to 240 mm. 

 There was almost a complete overlap in the 

 lengths of age-1 and age-2 fish, Age-2 fish 

 were smaller than in any other area. 



Fish caught in the Chesapeake Bay Area 

 ranged from 160 to 240 mm. The frequency 

 distribution was unimodal (197 mm,). Although 

 age-2 fish were slightly larger than age-1 

 fish, the two age groups could not be sep- 

 arated from each other by length. 



Table 6, — Sex ratio of Atlantic menhaden in purse 

 seine catches, by area and season, 1960 



In the Middle Atlantic Area, the lengths 

 ranged from 175 to 350 mm. A mode, repre- 

 senting age-2 fish, occurred at 222 mm., fol- 

 lowed by a minor peak, representing age-4 

 fish, at 307 mm. Age-2 fish were larger than 

 those in either the Chesapeake Bay or the 

 South Atlantic Areas. 



The length-frequency distribution of fish 

 caught in the North Atlantic Area was bimodal 

 and ranged from 220 to 355 mm. The primary 

 mode at 257 mm, represented age-2 fish, and 

 the secondary mode at 297 mm. represented 

 age-4 and older fish, Age-2 fish were larger 

 than those in any of the other areas during 

 the summer season. 



The length-frequency distribution of fish 

 taken in the North Carolina fall fishery was 

 negatively skew, due to the occurrence of 

 age-0 and age-lfish, but unimodal, with lengths 

 ranging from 70 to 354 mm. The mode at 302 

 mm, resulted from the relatively large per- 

 centage of fish age-4 and older. 



As in previous years, the females were 

 larger than the males (fig, 5), and the dif- 

 ference was greater among the older and 

 larger fish in the North Atlantic Area and 

 the North Carolina fall fishery. Among age-1 

 and age-2 fish caught in the other areas, the 

 difference was less evident. There was no 

 significant change from previous years in the 

 ratio of females to males (table 6), 



Weight Composition 



The weight-frequency distributions (in per- 

 cent) of fish in catch samples from each 

 area and from the North Carolina fall fishery 

 are shown in figure 6 (see also appendix 

 table 6-10), 



The predominance of age-2 fish was re- 

 flected in each distribution except that for 

 the North Carolina fall fishery. In the South 

 Atlantic Area, the presence of age-1 fish of a 

 smaller size range resulted in a bimodal 

 distribution. In the Chesapeake Bay Area, the 

 distribution was unimodal, and individual age 

 groups were indistinguishable. The distribu- 

 tion in the Middle Atlantic Area was unimodal 

 and due to the occurrence of older fish, posi- 

 tively skew. In the North Atlantic Area, the 

 bimodal distribution reflected the predomi- 

 nance of age-2 and age-4 fish, and the wide 

 range reflected the occurrence of several age 

 groups. The wide range and the absence of 

 any dominant mode in the frequency curve for 

 the North Carolina fall fishery resulted from 

 the occurrence, in relatively equal numbers, 

 of all age groups. 



Mean Length and Weight 



The mean lengths and weights of fish in 

 purse seine catches for the years 1955 to 1960 



13 



