period during which haddock spawn, or im- 

 mediately prior to it, when the fish slacken 

 off in their feeding. The decrease in foods 

 resulted in a disproportionately high percent- 

 age of mucus . 



EWfferences in diet of specimens cau^t 

 during the same month but from different 

 locations within the food-type area were suf- 

 ficiently large to overshadow any seasonal 

 dietary changes that may have existed. From 

 the data at hand, it appears that seasonal 

 variations in diet composition of Georges 

 Bank haddock are relatively minor in compari- 

 son to the variations associated with geo- 

 graphical distribution. 



SIZE OF FOOD ORGANISMS 



Haddock have a rather small, subterminal 

 mouth and consequently are prevented from 

 taking large articles of food. Most of the 

 food organisms were small - between 1/2 

 and 3 centimeters in length - and the major- 

 ity were narrow, elongate forms. Exceptions 

 occurred, of course, but in general the food 

 Items with two dimensions greater than 1 or 

 2 centimeters in length were taken only by 

 the very largest haddock. 



Differences in the size of food organisms 

 were, to some extent, correlated directly 

 with the size of haddock . Small organisms 

 such as amphipods, phyllodocid worms, cuma- 

 ceans, and isopods were dominant in the food 

 of small (14 - 30 centimeters) haddock. 

 Large haddock (40 - 75 centimeters) con- 

 tamed the greatest share of fish, sipunculids, 

 holothurians, asteroids, cephalopods, and 

 other comparatively large items . The larg- 

 est creature found in the haddock's diet was 

 a squid, (Illex ) whose body measured 20 centi- 

 meters in length and whose volume was 103 

 cubic centimeters. The predator of this squid 

 measured 52 centimeters in body length. Food 

 items as large as this are rarely encountered 

 in the stomach contents of haddock. It is im- 

 portant to note, however, that small organisms 



were common in large haddock . In fact 

 the predominant food in some collections of 

 large haddock were organisms whose great- 

 est lengths were less than 1 centimetei 

 This information suggests that the upper 

 limit in size of food organisms is dependent 

 upon the haddock's size, but through either 

 preference or necessity small items con- 

 stituted the bulk of the food of both large and 

 small haddock . 



Many species of groundfish with which 

 haddock associate and with which they must 

 compete for food, such as the cod, pollock, 

 hake, skates, etc., have proportionately 

 larger mouths . This puts the haddock at a 

 disadvantage in competing for the larger 

 food items, but the haddock, because their 

 lips are muscular and somewhat prehensile, 

 are better adapted than most of their associ- 

 ates for pulling worms and other soft-bodied 

 creatures out of the ocean floor. 



ACKNOWLEDGMENTS 



The writer wishes to express his appre- 

 ciation to fellow staff members and to Messrs. 

 Allan M . Barker, Robert L . Cory, Jim W . 

 McKee, and David Miller, formerly of the 

 Woods Hole Oceanographic Institution, for 

 their assistance with the collection of study 

 materials . Mr . Wendell Patton tabulated 

 much of the numerical data . The author is 

 also indebted to Dr . Marion H . Pettihone, 

 University of New Hampshire, and Drs . 

 Fenner A. Chace, Jr. and Clarence R. Shoe- 

 maker, and their associates at the Smithson- 

 ian Institution, U. S. National Museum, for 

 the identification of many invertebrate animals . 



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