(5. 7%). The Lysianassidae (1.8%) and amphipod tubes (1.4<Vo) 

 accounted for most of this group. Although unimportant as prey, 

 we recorded one instance of predation on the American lobster, 

 Himcrus americanus (1.2%), which is interesting to note because 

 of its rarity as prey. The only other taxon of any importance was 

 the echinoderms in Western Nova Scotia (16.3%), where most of 

 th's prey group was identified as the sea cucumber, Stereoderma 

 unisemita (10.5%). 



American plaice. — American plaice were collected for 

 stomach content analysis in four of the five geographic areas 

 (Table 6). In Southern New England the sample size, number of 

 sampling stations, and, more importantly, the total quantity of 

 prey was relatively small so that comparisons between this 

 region and the three other areas may not be very meaningful. In 

 fact, the diet of American plaice in Southern New England dif- 

 fered substantially from the other areas. In contrast to all other 

 areas echinoderms (3.8%) were of little importance while 

 arthropods (57.6%), especially amphipods (38.4%), were 

 preyed on heavily. A large proportion of the amphipod prey 

 was, however, identified as amphipod tubes (26.6%). The other 

 arthropod of importance in the fish stomachs from Southern 

 New England was the sand shrimp, Crangon septemspinosa 

 (15.2%), but like the Amphipoda, sand shrimp were also preyed 

 on in other geographic areas and a greater number of stomachs 

 would need to be examined before this relatively high level of 

 predation could be considered unusual. In the three remaining 

 geographic regions the number of fish stomachs examined, the 

 total quantity of prey consumed, and the average size of fish 

 were similar so that a comparison of the diets should reflect true 

 regional differences in feeding. 



On Georges Bank echinoderms were the primary prey total- 

 ling shghtly >90% of the diet. The sand dollar, Echinarachnius 

 parma, accounted for 70.3% of this prey group. In the Gulf of 

 Maine and Western Nova Scotia echinoids were also preyed on 

 but to a lesser extent. The echinoid remains from the Gulf of 

 Maine plaice stomachs (7.1%) were not identified below the 

 family level, but in Western Nova Scotia Echinarachnius parma 

 (38.4%) was again the single most important prey. Ophiuroids 

 were also an important prey and in all areas the ophiuroid 

 remains were identified to the generic level as Ophiura (5.9, 

 26.7, and 5.6% for Georges Bank, Gulf of Maine, and Western 

 Nova Scotia, respectively) and in each area a percentage of this 

 generic classification was identified to the species level as O. 

 sarsi (1.3, 10.7, and 1.5% for the areas as Hsted above). 



Arthropods were generally the second major taxon preyed on 

 by American plaice in all three geographic regions. In all areas 

 the Pandalidae were of primary importance. Both Dichelopan- 

 dalus leptocerus and Pandalus were identified in the stomach 

 contents. On Georges Bank D. leptocerus (1.5%) was more 

 important than Pandalus but in the Gulf of Maine the reverse 

 was true [Pandalus (4.3%) vs. D. leptocerus (1.8%)]. In 

 Western Nova Scotia both were preyed on equally (2.0% vs. 

 2.3%). In Western Nova Scotia the Euphausiacea contributed 

 slightly more to the diet than the Pandalidae (6.3% vs. 5.7%, 

 respectively) and virtually all the euphausiids were identified as 

 Meganyctiphanes norvegica (6.2%). In two of the areas, 

 Georges Bank and Western Nova Scotia, the only other impor- 

 tant arthropod family was the Paguridae. In both regions 

 Pagurus acadianus (Georges Bank 2.4% and Western Nova 

 Scotia 16.7%) was the primary species but on Georges Bank P. 

 pubescens (0.1%) was also identified in the stomach contents. 



Table 6. — Geographic breakdown of Ibe slomach conlents of American plaice, 

 Hippoglossoides platessoides, in Ihe northwesl Atlantic. Data are expressed as a 

 percentage weight for fish collected during Ibe spring and autumn bottom trawl 

 survey cruises, 1969-72. ( + indicates present but <0.1''/o.) 



Other taxa were generally of relatively minor importance as 

 prey except in the Gulf of Maine where both Mollusca (22.6%) 

 and Annelida (9.5%) contributed significantly to the diet. The 

 Bivalvia were the most important class of molluscs (22.3%) and 

 Yolida (1 1 .2%) and Chlamys islandica (4. 1 %) were the primary 

 prey within the class. Most of the annelids were identified as 

 either polychaete tubes (2.6%) or annelid remains (1.8%) but 

 the single most important family was the Ampharetidae (1.2%) 

 and the two species identified within this family y/trt Ampharete 

 acutifrons (kOAVo) and Melinna cristata (1.0%). 



Yellowtail founder. — Yellowtail flounder were collected for 

 stomach contents analysis in reasonably large numbers from all 



