Wuenschel et al.: Habitat and diet overlap of 4 piscivorous fishes 
353 
species or size classes, increasing the potential for both 
interspecific and intraspecific interactions. Interspe- 
cific competition and resource partitioning have been 
well documented for fish species in freshwater systems 
(Persson et ah, 1999; Sutton and Ney, 2002; Bellgraph 
et ah, 2008), where the potential for interactions may 
be greater than it is in marine systems given the closed 
nature of freshwater systems and fish populations. 
This interspecific competition and resource partition- 
ing may apply to some degree in estuaries as well, as 
has been reviewed for European estuaries (Elliot and 
Hemingway, 2002). In contrast, because of the openness 
of marine populations and the ability of individuals to 
move great distances, interspecific competition in most 
marine systems likely is highly variable in time and 
space, making it more difficult to document and study 
interspecific competition in marine systems than in 
freshwater populations. 
Summer Flounder, Weakfish, Bluefish, and Striped 
Bass are important commercial and recreational spe- 
cies in New Jersey and elsewhere on the east coast 
of the United States. These species co-occur seasonally 
and feed on similar prey, indicating potential for com- 
petitive interactions. However, studies of food habits 
for these species generally have focused on estuarine 
collections (Gartland et ah, 2006; Latour et ah, 2008) 
or have been limited to seasonal, offshore (at depths 
of 5-400 m) collections aggregated over multiple years 
(Buckel et al., 1999b, Garrison and Link, 2000a, 2000b; 
Link et ah, 2002; Overton et ah, 2008; Woodland et 
al., 2011). Further, most prior studies on these spe- 
cies typically have focused on a single (Gartland et ah, 
2006; Latour et ah, 2008) or a pair of species (Buckel 
and McKown, 2002; Buckel et ah, 2009). Because of 
the spatial and temporal variability in competitive 
interactions between migratory fishes, studies span- 
Figure t 
(A) Study area where Summer Flounder (Paralichthys dentatus), Weakfish (Cynoscion regalis), Bluefish (Poma- 
tomus saltatrix), and Striped Bass ( Morone saxatilis ) were sampled in 2005 along the northeastern coast of the 
United States for a 5-month study of habitat and diet overlap of these 4 piscivorous fishes and (B) sample col- 
lection area off New Jersey with the 15 strata outlined (strata were defined on the basis of latitudinal boundar- 
ies and depth contours of 9, 18, and 27 m). In June, August, and October, all strata were sampled. In July and 
September, only strata indicated with diagonal lines were sampled. 
