9 . The depth distribution during the spring indicated a migration of older fish 

 into shoaler water at this time. EXiring this season the greatest concentration of 

 marketable haddock occurred in water shoaier thian 60 fathoms. 



10. The depth distribution of Georges Bank haddock during both spring and 

 summer was similar to that of haddock in other regions and is apparently due to 

 spawning and feeding migrations . This depth distribution was similar over various 

 bottom types and although greater numbers of haddock occurred over sand than over 

 mud bottoms, this distribution was incidental to the depth distribution. 



11. The age composition of the commercial catch and of the census data when 

 weighted in terms of effort by subarea of the commercial fleet were very similar, 

 which fact further substantiates the reliability of the sampling methods . 



12. Concentration charts showing tlie fishing location of the commercial fleet 

 during July and August and the distribution of the various age haddock as determined 

 from census cruises during similar periods reveal that the commercial fleet con- 

 centrated their efforts on younger haddock ( 2 to 4 -year olds) and principally in sub- 

 areas J and M and in depths between 30 and 60 fathoms and did not sample large areas 

 of deeper water (more than 90 fathoms) in subareas G, H, and J where the majority of 

 the older haddock occurred. This fact is further substantiated by the age composition 

 of the commercial landings which reveal that it is only during the spawning season 

 (spring) at which time these older haddock have moved into shoaler water that 

 appreciable numbers of older haddock are caught. 



13 Numerical mortalities based on census data were consistent with expected 

 results in that they decreased umformly for all age fish with shorter time limits 

 between successive samplings. A marked contrast exists between these mortalities 

 which show a decrease in the mortality of older fish and similar figures determined 

 from the abundance data of the commercial catch over a considerable number of years 

 which show a definite increase in the mortality of older fish. This is explained by the 

 fact that these fish are being under sampled by the commercial fleet because of their 

 location (deeper water) and not by the fact that there is an increased effort expended 

 by the commercial fleet on these older fish with "the resulting increase in fishing 

 mortality. 



14. The consistency of the age distribution by years, season, subareas, and 

 depth; the uniformity of the mortalities determined from the spring and summer data; 

 the accuracy of the year -class strength prediction based on the catch of zero -ring 

 fish which was known to be the least reliable sample; and the similarity of the age dis- 

 tribution determined from census and commercial data all attest to the reliability and 

 value of the data obtained and the methods used. It is believed that such methods with 

 certain adaptations for specific needs and accuracy desired would prove most valuable 

 in the study of migrations, year class strength, mortality and growth rates, and their 

 relation to ecological conditions . 



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