The depth distribution during the spring was markedly different from the 

 distribution during the summer months. The catch per tow and weights per tow of 

 unmarketable fish (1-2 years) and scrod (3-4 yeais) decreased with increasing depth. 

 The catch per tow of all marketable haddock (3-9-H years) decreased with increasing 

 depth, but was practically uniform between 31 and 90 fathoms. The weight per tow 

 of all marketable haddock, however, was slightly greater in depth zone III than in depth 

 zone 11. The catch per tow and weight per tow of large haddock (5-9+ years) was 

 greatest in depth zone I, followed in descending order by depth zones III, II, and IV . 

 Depth zone IV, where in summer the greatest concentration of large haddock were 

 found, was the least productive area for all age groups . 



It appears then that at this season it would have been most profitable to fish 

 in shoal water (0-30 fathoms), but also at this depth the greatest destruction of im- 

 mature fish would occur. From the conservation st;andpoint; depth zone III would be 

 the most desirable fishing area. However, a m.uch more thorough coverage of the 

 bank at this season is needed to substantiate tJiese conclusions . 



This inshore movement of older fish during the spring is evidenced in the land- 

 ings of the commercial fleet which show a marked increase in the percentage of older 

 haddock at this season . Such a movement is associated with spawning activity and 

 has also been found to occur in European stocks of haddock (Thompson 1929b). 



Although there is a slight variation from year to year; the spawning season 

 for Georges Bank haddock is mainly from February through April (Bigelow and Welsh, 

 1942, Walford 1938). These spawning dates are further substantiated by the fact 

 that large numbers of ripe fish were taken during the spring cruise of the Albatross III . 

 Thus the above data for the spring represents conditions existing during the spawning 

 season . 



The age at maturity (age at which spawning occurs) varies considerably with 

 location. Bigelow and Welsh (1925) give 4-5 years as the age at maturity for haddock 

 in the Gulf of Maine area near Cape Ann . More recent data obtained on the Albatross 

 in and commercial vessels during March of 1949 and 1950 indicate that the age at 

 maturity for Georges Bank haddock is considerably earlier than this and is different 

 for males and females. The following table (table 13) gives the age at maturity for 

 haddock on Georges Bank, Browns Bank, the Newfoundland Banks, and the North Sea. 



The age at maturity of Georges Barik haddock is very similar to that for the 

 Nortli Sea, while Bigelow' s figures for the Gulf of Maine coincide with Albatross III 

 observations on Browns Bank and with Thompson's figures for Newfoundland and 

 Iceland, the haddock from the latter area maturing at 4-6 years (Thompson 1929A).z.' 



4/ There exists slight evidence to the effect that the age at first maturity varies 

 between year classes and that first maturity ofccurs in the larger fish of a certain 

 year class. (Hansen 1949). 



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