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Fishery Bulletin 115(2) 
c 
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Diet similarity 
B 229 - 
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Diet similarity 
Figure 3 
Dendrograms derived from hierarchical cluster analyses and that represent the 
dietary similarities of (A) winter flounder (Pseudopleuronectes americaiius) and 
(B) summer flounder (Paralichtliys dentatus) across 5-mm or 10-mm increments 
of “preserved” total length (i.e., measured in the laboratory after specimens were 
preserved in 70% ethanol). Vertical gray bars represent distinct dietary groups 
determined from cluster analyses and similarity profiling. Winter and summer 
flounder were collected from the Seekonk and Taunton Rivers during 2009-2015. 
September). Interannual variations in diet (2009-2015) 
were excluded from these analyses because some sites 
were not consistently sampled across years (i.e., SRI, 
SR3, and TR3). 
If significant results (P<0.05) were obtained with 
the PERMANOVA models, SIMPER analyses were con¬ 
ducted to determine which prey taxa contributed to 
the observed differences in diet of winter and summer 
flounder across sites or months. Further, to aid in the 
interpretation of the PERMANOVA results, principal 
coordinate analysis (PCO) was used to visualize the 
diet composition data. This method provides a direct 
projection of data points in space according to their ac¬ 
tual dissimilarities, and PCO axes quantify the amount 
of variation inherent in the resemblance matrix that is 
attributable to each successive PCO axis (expressed as 
