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Fishery Bulletin 115(2) 
O WF (Small) 
V WF (Small-medium) 
□ WF (Medium-large) 
AWF (Large) 
• SF (Small) 
▼ SF (Small-medium) 
1 SF (Medium-large) 
ASf (Large) 
Figure 8 
Biplot from principal coordinate analysis (PCO) that represents the dis¬ 
similarities in diet of winter flounder {Pseudopleuronectes americanus; 
WF) and summer flounder (Paralichthys dentatus; SF) as a function of 
species type and size class (winter and summer flounder, respectively: 
small, <39 mm TL and <59 mm TL; small-medium, 40-59 mm TL and 60- 
79 mm TL; medium-large, 60-79 mm TL and 80-119 mm TL; and large, 
>80 mm TL and >120 mm TL). Arrows superimposed on the PCO biplots 
represent vectors of dominant prey taxa, and vectors correspond with the 
monotonic relationships between the dietary importance of a prey and the 
PCO axes. The first (PCOl) and second (PC02) ordination axes correspond 
with species-type and body size, respectively, and quantify the percentage 
of total variation in diets of winter and summer flounder. Winter and 
summer flounder were collected from the Seekonk and Taunton Rivers 
during 2009-2015. 
the upper reaches of the Seekonk and Taunton Rivers 
(SR1-SR2; TR1-TR2) (Fig. 4C). 
Discussion 
Intraspecific diet composition 
This study provides a comprehensive analysis of the 
diet composition of age-0 winter flounder and summer 
flounder collected from 2 southern New England tidal 
rivers. Accordingly, both flounder species from this geo¬ 
graphic area and habitat type had a generalist feed¬ 
ing strategy, as determined by the wide variety of prey 
consumed during the early juvenile life stage (33 and 
32 novel prey taxa, respectively). Winter flounder fed 
predominantly on small crustaceans (e.g., amphipods, 
copepods, isopods, ostracods, and crab megalope) and 
soft-body prey (e.g., polychaetes, clam siphons, chirono- 
mid larvae, and nematodes). These results are consis¬ 
tent with previous analyses of the food habits of ju¬ 
venile winter flounder across their broader geographic 
distribution (from Newfoundland to Maryland: Stehlik 
and Meise, 2000, and references therein; Vivian et ah, 
2000; Shaheen et al., 2001; Link et al., 2002; Meng et 
al., 2008). Summer flounder also consumed a diverse 
range of crustaceans (e.g., shrimps, amphipods, cope- 
pods, cumaceans, and ostracods) and soft-tissue prey 
(e.g., polychaetes and clam siphons), as well as 8 iden¬ 
tifiable fish species. To the knowledge of the authors, 
this is the first description of the feeding habits of ju¬ 
venile summer flounder from southern New England 
nurseries and, more specifically, from oligomesohaline 
tidal rivers (mean salinity <20). 
