Table 9.— Geographic breakdown of food of the apolted hake, ('ro- 

 phycU reffiua, in the northwest Atlantic. Data are expressed as per- 

 centage weight, fur fish collected during the spring and autumn 

 bottom trawl survey cruises l%9-72. (Gulf of Maine and Western 

 Nova Scotia = no samples; ■*■ indicates present but <0. 1%.) 



Prey 



Middle 

 Atlantic 



Southern 

 New England Georges Bank 



POLYCHAETA 0-4 



Nereidiformia 



Terebelliformia 



Sabelliformia 



Other Polvchaeta 

 CRISTACEA -IS.e 



Amphipoda 



Mysidacea 



Euphausiacea 



Pandalidae 



Crangonidae 



Axiidae 



Paguridae 



Majidae 



Cancridae 



Other Decapoda 



Other Crustacea 

 MOLLUSCA 16.6 



Gastropoda 



Pelecypoda 



Cephalopoda 



Other Mollusca 

 ECHINODERMATA 



Echinoidea 



Ophiuroidea 



Other Echinodermata 

 PISCES 28.5 



Ciupeidae 



Gadidae 



Scorn bridae 



Scorpaenidae 



Bothidae 



Pleuronectidae 



Other Pisces 

 Other groups + 



Animal remains 5.7 



Sand and rock 0.2 



O.l 



0.3 



8.0 



+ 



+ 



3.8 



5.0 



0.1 



+ 

 10.3 

 14.5 



6.9 



0.1 

 0.4 

 16.1 



0.6 



46.8 



1.1 



0.1 



0.5 



6.2 



0.1 

 4.3 

 2.6 

 0.1 

 0.1 



1.1 



31.9 



0.4 



1.0 

 0.1 



6.8 



71.6 



2.9 



1.2 



0.3 

 2.4 



71.6 



45.1 



0.3 



6.8 



1.7 



0.8 

 19.2 



0.3 

 9.1 



1.9 



0.8 



33.0 



0.3 



0.1 

 5.8 

 0.5 



+ 

 21.3 



Number of stomachs 689 183 4 



Percentage of empty stomachs 10.5 31.0 25.0 



Mean weight per stomach (g) 0.8 1.9 2.8 



Mean predator fork length (cm) 18.2 26.2 24.1 



Number of sampling stations 45 17 2 



nectid, Limanda ferruginea (0.8%); and "Other Pisces" 

 (19.2%) such as the snake eel (0.2%), and lanternfish 

 (family Myctophidae) (3.9%), constituted the fish prey. 

 In Southern New England the fawn cusk-eel (1.1%) and 

 some unidentified cusk eels (10.8'c), together with Atlan- 

 tic mackerel (9.1%), the Gulf Stream flounder (1.9'0, 

 and silver hake (1.1%), represented a large part of the 

 fish consumed. 



Haddock, Melanogrammus aeglefinus. — Few had- 

 dock were collected in the Middle Atlantic and South- 

 em New England and therefore the following discussion 

 is limited primarily to the three other geographic areas 

 (Table 10). 



Fish accounted for more than one-fourth (28.4'r) of the 

 haddock's diet on Georges Bank whereas fish were rea- 



sonably insignificant in all the other areas. This shift in 

 food was not, however, due to a change in feeding 

 strategy but rather was entirely due to the consumption 

 of herring eggs. This implies that haddock prey heavily 

 on herring spawn when it is available. Polychaetes were 

 also more important prey on Georges Bank (23.5%) than 

 in the other areas. The "Other Polychaeta" category 

 contributed the largest {percentage (18.3'() with Ammo- 

 trypane aulogaster (8.3' c) being the most important 

 animal. Laonice (0.1%), Ophelia (<0.1%), Scalibregma 

 (<0.1%), and Sternaspis (0.1%) were other polychaetes 

 identified in the stomach contents. None of the Tere- 

 belliformia (2.1' c) could be identified below suborder 

 and Chone infundibuliformis (0.3' c) was the only 

 Sabelliformia (2.1'f ) identified to species. The third prey 

 group that was of any significance was the crustaceans 

 (16.0':'f). Amphipods (7.1'c) made up the largest portion 

 but the individual species of amphipods usually ac- 

 counted for <0.1'o. As a group the gammarid amphi- 

 pods were the most important, with species such as Un- 

 ciola irrorata (<0.1%), Casco bigelowi (<0.1%), Anonyx 

 sp. (0.1%), Leptocerus pinguis (0.1%), and Pleustes sp. 

 (<0.1%) having been found in the haddock stomachs. 

 Echinoderms (7.8' c) and molluscs (3.8%) were the least 

 important prey groups for Georges Bank haddock. Brittle 

 stars, such as Ophiopholis aculeata (2.4'f), were the 

 most important echinoderms, while pelecypods like 

 Astarte (0.2%) and Pecten (0.1%) were the more impor- 

 tant molluscs that could be identified. Sand and rocks 

 (15.3'f) were more prevalent in the haddock stomachs 

 collected on Georges Bank than elsewhere, possibly be- 

 cause polychaetes and pelecyjjods accounted for a larger 

 percentage of the diet here than in the other areas. 



The haddock's food in the Gulf of Maine and Western 

 Nova Scotia were quite different from those in the other 

 three geographic areas, but within these two areas the 

 prey was similar. For example, in both areas half the diet 

 consisted of echinoderms. Similarly, crustaceans and 

 polychaetes contributed between 10 and 15% of the diet 

 and molluscs between 1 and 3%. Brittle stars were the 

 main food item, with Ophiura (16.2%) being of primary 

 importance in the Gulf of Maine. However, Amphiura 

 (0.8'c), Ophiopholis (0.4' c), and Ophiacantha bidentata 

 (<0.1%), together with unidentified ophiuroid remains 

 (20.5%), are also included in this prey group. In Western 

 Nova Scotia three ophiuroids were eaten, Ophiopholis 

 (13.0'f), Ophiura (8.2'f), and Amphiopolis (0.2%), 

 together with some unidentifiable ophiuroid remains 

 (13.0'c). In the Gulf of Maine 15.2'r of the diet was 

 crustaceans. The "Other Decapoda" was the largest 

 group (5.9'c) primarily because of the shrimp Pasiphaea 

 (4.9%). The shrimp Pandalus (2.0%) was of secondary 

 importance as were euphausiids (1.9%) and gammarid 

 amphipods (1.8'r). Gammarid amphipods (3.4'c) as well 

 as the caprellid; Aeginina longicornis (0.3%), were the 

 main crustacean prey in Western Nova Scotia, while the 

 Axiide, both Axius (l.S'i) and Calocaris (0.5%), were of 

 secondary importance. Polychaetes were the only other 

 group accounting for much of the diet. The majority were 

 not identified below the order level, but in the Gulf of 



14 



