catch in the South Atlantic Area in 

 1957, however, was only about one- 

 tenth that of the 1955 year class at age 

 1 in 1956 and only about one -half that 

 of the 1954 year class at age 1 in 1955. 

 Thus the reduced summer catch in the 

 South Atlantic Area in 1957 appears to 

 have resulted from the below-average 

 recruitment of the 1956 year class to 

 the summer stock in the area. In con- 

 trast, the contributions of this year 

 class to the fishery in the Chesapeake 

 Bay and Middle Atlantic Areas ex- 

 ceeded those of the previous two year 

 classes at comparable age in 1955 and 

 1956, and its high level of abundance 

 in the former area was directly re- 

 sponsible for the large catch. It also 

 is noted that for the first time on rec- 

 ord, fish of age 1 occurred in the 

 catches in the North Atlantic Area. In 

 the North Carolina fall fishery this 

 year class accounted for a relatively 

 small share of the catch. However, 

 because adverse weather curtailed 

 fishing during the period when schools 

 were present in greatest concentra- 

 tions and because of selective fishing 

 by the fleet on schools of larger 

 fish, the younger age-groups prob- 

 ably were not represented in the 

 catches in proportion to their actual 

 abundance on the fishing grounds. As 

 was to be expected, our records show 

 that the 1956 year class made a sig- 

 nificant contribution to the catch in 

 1958. 



Based on its contributions during 

 the first 3 years of life (4.3 billion 

 fish), the 1955 year class appears to 

 be the largest to enter the fishery in 

 recent years. It- was first encountered 

 in abundance at age during the 1955 

 fall fishing season in North Carolina, 

 although the significance of their num- 

 ber in the catch was unknown (June and 

 Reintjes, 1959, p. 16). In the following 

 year at age 1 this year class was 

 heavily recruited to the sumnner stocks 

 in the South Atlantic and Chesapeake 

 Bay Areas and accounted for well over 

 one-half of the total purse-seine catch. 

 The possibility that at age 2 it would 

 contribute substantially to the 1957 

 catch was mentioned (June and Reintjes, 

 I960, p. 6). This year class accounted 

 for about two-fifths of the number of 



fish caught in 1957. Although variable 

 in availability, it was the main support 

 of the summer fishery in all areas 

 except Chesapeake Bay and, next to 

 the newly recruited 1957 year class, 

 contributed the greatest number of 

 individuals to the fall catch off the 

 coast of North Carolina. Furthermore, 

 this was the first year since initiation 

 of the catch-sampling program in the 

 North Atlantic Area (1953) that fish of 

 age 2 formed such an important share 

 of the catch in northern waters. From 

 the foregoing it would appear that, if 

 the catch per unit of effort of age-1 

 fish is a reliable measure of the 

 relative success of a year class, the 

 prospect of two relatively strong year 

 classes occurring in succession are 

 good. 



In contrast to the evidence pointing 

 to a high level of abundance of both 

 the 1955 and 1956 year classes, perti- 

 nent data relating to the 1954 year 

 class indicate that it was comparatively 

 weak. It also is evident that over the 

 past several years there has been a 

 noticeable decrease in the proportions 

 of older fish in the catches in both the 

 Middle and North Atlantic Areas. For 

 example, there were only about one- 

 half as many fish of age 4 and older 

 ages caught per unit of effort in 1957 

 as in 1955. This, of course, was due 

 partly to the influence on the 1955 

 catch of the very abundant 1951 year 

 class (age 4 in 1955), but it also is 

 noted that for the first time in the past 

 5 years, fish younger than age 3 con- 

 tributed substantially to the catch in 

 northern waters in 1957. Thus the 

 decline in the summer catch in the 

 North Atlantic Area could have resulted 

 from the relatively weak contribution 

 of the 1954 year class, coupled with a 

 reduced abundance of older year 

 classes. The extent to which reduced 

 availability of schools on the inshore 

 fishing grounds was responsible for 

 the low catch in the North Atlantic 

 Area is unknown. It is noted, however, 

 that nearly as many fish of age 4 and 

 older were caught off southern Long 

 Island during the closing weeks of the 

 season in the Middle Atlantic Area as 

 were taken during the entire summer 

 in the North Atlantic Area. 



18 



