Wuenschel et al.: Habitat and diet overlap of 4 piscivorous fishes 
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Month of year 
Figure 6 
Pairwise monthly overlap (a), from Schoener’s index, in habitat (open circles) and diet (triangles) 
between species size classes sampled from June to October in 2005 off the coast of New Jersey for 
this study. Habitat overlap is shown for all cases when both groups were captured in the same 
month. Diet overlap is shown only for groups with sufficient sample sizes (see main text). Hori- 
zontal dashed lines indicate biologically important overlap threshold (0.6). Species size classes are 
indicated in this manner: small, medium, and large Summer Flounder ( Paralichthys dentatus ), 
PdS, PdM, PdL; small, medium, and large Weakfish ( Cynoscion regalis), CrS, CrM, CrL; small and 
large Bluefish (Pomatomus saltatrix), PsS, PsL; and Striped Bass ( Morone saxatilis), Ms. 
June and July to levels >0.4 in September and October. 
Small and medium Weakfish had relatively high over- 
lap in diet, but lower overlap in habitat, with small 
and medium Summer Flounder from August to Octo- 
ber. The limited spatial distribution of Striped Bass, in 
addition to their absence during some months, resulted 
in a low degree of overlap in habitat with groups of 
other species, but Striped Bass were most abundant 
in the fall and, therefore, overlapped with the other 
predators at that time. 
Discussion 
The degree of habitat and diet overlap among Summer 
Flounder, Weakfish, Bluefish, and Striped Bass varied 
with size and season. The size classes of these 4 preda- 
tors examined in our study exhibited different patterns 
in spatial distribution, depth, and habitat use. Sum- 
mer Flounder were most evenly distributed throughout 
our study area — a pattern also observed in a longer 
(1982-2003) time series of sampling at generally deep- 
