Goldman et al.: Feeding habits of Pagrus pagrus and Balistes capriscus 
327 
in our study are not well studied in the southeast, and 
their population statuses are not well known. Changes 
in their status could have unanticipated consequences 
for commercial fish species like red porgy and gray 
triggerfish. The most significant predator-prey inter- 
actions are those between red porgy and decapods and 
bivalves and those between gray triggerfish and gas- 
tropods. The information reported here complements 
the findings of previous studies and provides a critical 
link between the biology of red porgy and gray trigger- 
fish and their role as predators in marine ecosystems. 
Although both species rely primarily on hard-bottom 
habitats for feeding, opportunistic prey switching al- 
lows both red porgy and gray triggerfish to adapt to 
ecological changes. This research and that of similar 
studies contribute to our understanding of the role of 
predators in changing ecosystems and provide fisheries 
managers with some of the data necessary for the im- 
plementation of an ecosystem-based approach to fish- 
eries management in the southeastern United States. 
Acknowledgments 
For their help with identification of prey items, we 
thank D. Burgess, J. Cowan, D. Knott, C. Willis, and D. 
Wyanski. Thanks are extended to the staffs of the Ma- 
rine Resources Monitoring Assessment and Prediction 
program and of the Southeast Fishery-independent 
Survey, NOAA Southeast Fisheries Science Center, and 
to the crews of the RV Palmetto and RV Savannah. 
G. Sedberry, W. Anderson, C. Barans, K. Spanik, and 
W. Bubley provided helpful comments on early drafts 
at the manuscript stage. This work was supported 
through funds provided by the Southeast Area Moni- 
toring and Assessment Program — South Atlantic. This 
paper is contribution number 734 from the South Caro- 
lina Marine Resources Division. 
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