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FISHERY BULLETIN OF THE FISH AND WILDLIFE SERVICE 



i — i — i — i — i — i — i — I — i — i — i — I — i — i — i — I — i — i — i — I — i — i — i — rn — r—i — | — i — i — r 



, I 



1942 1943 1944 1945 1946 1947 1948 1949 

 YEAR 



Figure 13. — Trend in relative apparent abundance, by 

 quarters, of yellowtail from the southern New England 

 stock, 1942 through 1949. 



i 1 1 1 1 1 1 1 1'-* 



LANDINGS 



RELATIVE APPARENT 

 ABUNDANCE 



£ 



U. 



o 



g 



< 



CO 



r> 

 o 



1942 1943 1944 1945 1946 1947 1948 1949 



Figure 14. — Trends in relative apparent abundance and 

 landings of yellowtail from the southern New England 

 stock, 1942 through 1949. 



Fishing Effort 



The catch per unit of effort as computed for 

 the selected trawlers leads naturally to an esti- 

 mate of the amount of fishing for yellowtail in 

 terms of the standard day, i. e., days fished by 

 small otter trawlers of between 26 and 50 gross 

 tons that landed more than 75-percent yellowtail 

 in the catch. The data (table 24) have been com- 

 puted from tables 7 and 23. 



Table 24. — Number of standard days fished for yellowtail on 

 southern New England grounds, by quarters, 1942-49 



It is obvious immediately that the seasonal dis- 

 tribution of fishing effort did not parallel the sea- 

 sonal distributions of catch and abundance. 

 Usually there was more fishing for yellowtail in 

 the first and fourth quarters of the year, less in 

 the third quarter, and least in the second quarter. 

 This is a reflection of a seasonal trend in the price 

 received for yellowtail and the relative attractive- 

 ness of other fisheries. During the winter, yellow- 

 tail usually was higher in price and more easily 

 caught than other species, but during the spring 

 and summer the price declined as winter flounder, 

 scup, whiting, and other species became available. 

 The large decrease in the amount of fishing for 

 yellowtail during the summer months between 

 1948 and 1949 is of interest. This occurred be- 

 cause of a diversion of the fleet to the newly de- 

 veloped "trash" fishery as described by Snow 

 (1950). 



AGE DETERMINATION 



The ages of a large number of yellowtail 

 flounder were determined for two purposes: (1) 

 To estimate the age composition of the landings 

 in each year and thereby obtain an estimate of 

 the recruitment and mortality rates; and (2) to 

 estimate the rate of growth. 



Early in the investigation consideration was 

 given to the best method of determining the age 

 of the fish. The Petersen method of using modes 

 in the length-frequency distribution showed little 



