172 



Fishery Bulletin 100(2) 



Table 2 



Stomach contents of bluefin tuna caught off New England during 1988-92. Prey species are combined for all five study areas, 

 including 12 samples from outside of the study areas. Percent frequency of occurrence C^'t O) and percent weight C^^'r W I data were 

 determined from the 568 stomach samples that contained prey. 



Prey species 



Sand lance 



Atlantic herring 



Atlantic mackerel 



Bluefish 



Butterfish 



Silver hake 



Windowpane 



Hake 



Winter flounder 



Atlantic menhaden 



Sea horse 



Atlantic cod 



Fourspot flounder 



American plaice 



Wrymouth 



Pollock 



Filefish 



Halflieak 



Longhorn sculpin 



Unidentified fish 



Spiny dogfish 



Skate 



Skate egg case 



Squid 



Octopus 



Shrimp 



Lobster 



Argonaut 



Crab 



Salp 



Fig sponge 



Finger sponge 



Frequency of 

 occurrence 



Total weight 



(gl 



Ammodytes (spp. ) 



Cliipca harengus 



Scomber scui/ibrus 



Pom a torn ii s saltatrix 



Pi-prihis tnacanthiis 



Mcrlucciua bilineans 



Scoptha/miiK aqiiosus 



Urophycia (spp.) 



P.vuclopleuroncctes americanus 



Brevoortia ty ran mis 



Hippocampus erect us 



Gadus morhua 



Paralichthys oblongus 



Hippoglussoidcs platessoides 



Ciyptacanthodes masculatiis 



Pullachius virens 



Monocanlhus luspidus 



Hyporhamphus unifasciatus 



Myoxocephalus octodecimspinosus 



Teleostei 



Squahis acanthias 



Raja (spp. I 



Raja ( spp. 1 



Cephalopoda 



Cephalopoda 



Pandalus (spp.) 



Homarus americanus 



Argonauta argo 



Cancer (spp.) 



Salpidae 



Suberites ficus 



Haliclona oculata 



Stomachs with chum and prey 

 Stomachs with chum only 

 Empty stomachs 

 Total stomachs with prey 

 Total stomachs sampled 



194 



167 



108 



55 



21 



16 



12 



11 



8 



7 



7 



6 



2 



2 



2 



1 



1 



1 



1 



34 



13 



13 



3 



186 



1 



5 



2 



2 



2 



2 



30 



1 



95 



45 



206 



568 



819 



YcO 



% W 



567,230 

 723,700 



Giant bluefin were scarce in this area during the study 

 period and numerous samples could not be used because 

 the bluefin tuna were caught in association with trawler 

 fleet discards. This area is distinguished from the others 

 by a predominance of juvenile bluefin tuna . Four prey 

 species were unique to this area: lined sea horse (Hip- 

 pocampus erectus), argonaut {Argonauta argo), planehead 

 filefish (Monocauthus hispiduxl, and octopus (Cephalop- 



oda ). The filefish and seahorse were associated with bluefin 

 tuna foraging at sargassum weed communities. Squid and 

 Atlantic mackerel were the two most important prey for 

 this area. The frequency of occurrence and percentage of 

 prey weight for mackerel and butterfish were the highest 

 among study areas. Combined stomach-contents biomass 

 for squid, mackerel, and butterfish represented nearly 

 809;^ of the stomach contents for this area. 



