The effort of the commercial fleet during this period was concentrated in water 

 shoaler than 60 fathoms (fig. 17). The reason the fishermen restricted their efforts 

 to the shoaler water when there were available more pounds of large haddock in deep 

 water is not immediately apparent. Perhaps they were unaware of the presence of 

 these fish. If in fishing operations they gradually extended their drags from the pro- 

 ductive depth zone II into deeper water they would be moving into the 61-90 fathom 

 deep zone which was the least productive zone. It is possible, then, that depth zone 

 in represented a barrier to the deeper, more productive areas . 



Furthermore, the fact that this depth distribution is seasonal (see page 31) 

 could also explain why the fishermen may not be aware of it. 



The greater expense of fishing in deeper water must also be taken into considera- 

 tion. Setting the gear in deep water is more difficult and hauling requires much more 

 time. There is also the danger of tearing the net on the rough bottom in the lesser 

 known depths . 



The presence of a greater number of trash fish or a smaller number of otlier 

 marketable species, however, does not appear to be a justifiable reason for avoiding 

 deeper water as a further analysis of the Albatross III c ensus data revealed that the 

 proportions of marketable and unmarketable fish 2/ of other species did not fluctuate 

 appreciably with depth. 



The above study of depth relations is based on records for the bank as a whole. 

 In the preceding section dealing with the variations of the catch in different subareas 

 it was noted that subareas G and H consistently had the highest catch per tow and the 

 highest percentage of older haddock (5 years). Correlating this with the fact that 

 older haddock were more abundant in deeper water, it is interesting to note from 

 fig. 11 and table 9 that the subareas yielding the greatest concentration of older 

 haddock are the ones having the greatest area of water deeper than 90 fathoms. 



2J Whether a fish is marketable or not depends largely upon the amounts caught, 

 the purpose of the trip, and where the fish are to be sold. For example, vessels 

 fishing out of Boston concentrate their efforts on haddock and in the Georges Bank 

 area while vessels fishing out of Gloucester fish primarily for redfish and in the 

 Gulf of Maine. The Boston boats discard redfish, which are found only in depth zone 

 iV, for there is little market for them in Boston, while the Gloucester fleet finds 

 a markel: for both redfish and haddock . 



26 



