130 
John Dodrill et al. 
intact stomachs contained 2-23 fresh Portunus spinicarpus, a total 
of 93 individuals. The only other remains found in these stomachs 
were two small, well-digested fish possible from previous feeding, 
one Solenocera atlantidis , and one bottom dwelling crab, Calappa 
angusta. Assuming that P. spinicarpus was locally abundant, snowy 
grouper apparently fed in the water column, ignored bottom organ- 
isms, and selected the most abundant prey at that site. At the same 
depth on the same day 2 km away, P. spinicarpus was not present 
in E. niveatus stomachs, nor were they on a later occasion at the 
original site. At other sites, feeding emphasis was on bottom-dwell- 
ing crabs, often adults of the same species and size or species with 
similar habits. 
Third, low food variety within individuals might be 
volumetrically limited by the number of prey items that can be 
accommodated. Fewer large prey such as adult or subadult brachyurans 
will fit into the stomach of even a large snowy grouper. In one 
snowy grouper (930 mm TL), four food items, Ovalipes stephensoni. 
Cancer irroratus, and two Ilex illecebrosus totaled a volume of 486 
mL, along with two additional squid beaks (1 mL). This was the 
greatest volume from any grouper stomach in our study (Table 5). 
CONCLUSIONS 
The snowy grouper is one of the most important large, 
deep-reef, tertiary predators found on the outer continental shelf 
edge and upper slope off central North Carolina. An analysis of 
5,088 snowy grouper, 335-1,100 mm TL, collected during 30 com- 
mercial bottom fishing trips in waters 137-238-m deep, revealed a 
diet dominated by crustaceans, particularly adult and subadult 
brachyurans (89.9% by number; 71.1% by volume). Small, benthic, 
midwater, schooling and nonschooling, reef-associated fishes 
(6.2% by number; 17.5% by volume) were of secondary impor- 
tance, followed by squids (2.2% by number; 9.8% volume). 
The abundance of decapods found in the diet might result 
from the reduced digestive rates for brachyurans compared to small 
(<200 mm TL) fish or squid. Crabs are also more accessible than 
fishes to slow-moving grouper, which probably feed by ambushing 
prey. In contrast to more slender, piscivorous Mycteroperca grouper 
species, snowy grouper probably are not capable of sustained or 
high-speed pursuit because of their stout bodies and sedentary na- 
ture. All prey were swallowed whole, and large brachuryans ( Can- 
cer sp., Ovalipes stephensoni) were found in larger grouper. 
Slow speed, seasonal territoriality, apparent disuse of plank- 
tonic organisms or sessile invertebrates, absolute size of prey, and 
close association with the bottom probably limit variety of prey 
