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John Dodrill et al. 
crush large prey as well as armored sessile organisms. Vermilion 
snapper feed on the bottom and to at least 5 m off the bottom, 
based on our fishing experience in 64-82 m. Most food items were 
pelagic, planktonic, or epibenthic (Grimes 1979) and were juveniles 
or larvae of many species (Dixon 1975, Grimes 1979). 
Prey Variability — Snappers and groupers rely on many 
different types of foods; however, the diets of snappers are more 
diverse (Parrish 1987). The diet of adult snowy grouper included 
few prey species compared with other reef fishes caught at depths 
of 100 m or less. Prey categories, reduced to lowest taxa from our 
study combined with NMFS and BLM data, were 29 for snowy 
grouper, compared to 199 for vermilion snapper and 121 for red 
porgy (South Carolina Wildlife Marine Resource Department 1982). 
At depths of 100 m or less, hard-bottom faunal diversity is greater 
than at 140 m or deeper. Parrish (1987) suggested that where many 
species occupy small, discrete, hard-bottom areas, greater diet range 
reduced competition among reef fishes. Below a depth of 140 m 
many reef fish species disappear, and the need for a diversified 
diet to reduce feeding competition might be lessened for adult snowy 
grouper. 
Intact grouper stomachs showed low prey diversity per 
individual stomach (Table 6). In a representative sample of 23 in- 
tact stomachs where no regurgitation appeared to have occurred, 16 
stomachs had 1 species, 21 had 1 or 2 species, and only 2 had 3 
or 4 species. A similar pattern was seen with the few E. flavolimbatus 
and E. nigritus stomachs examined (see Competition section). 
There are three possible explanations for low species 
variability in an individual stomach. First, a large number of deca- 
pod species is not available in the limited depth range and geo- 
graphic area sampled. Although Herbst et al. (1979) recorded 291 
decapod species from Carolina shelf waters, Wenner and Read (1982) 
trawled only 54 species from the 111-183-m-depth range in the 
South Atlantic Bight, fewer than at inshore depth ranges of 28-55 
m (87 species) or 56-110 m (84 species). Barans and Burrell (1976) 
reported 74 fish species trawled at 111-183 m in spring, declining 
to 43 species in summer. If we assume that snowy grouper are 
seasonally territorial and forage limited distances, prey possibilities 
for an individual fish during a specific feeding period are further 
reduced. Wenner and Read (1982), in 30-minute trawl tows at 111- 
183 m, averaged 3 decapod species and 25 individuals per tow. 
Second, grouper are opportunistic feeders, focusing on 
whatever species are readily available, and they do not seek prey 
that is less common or more difficult to catch. For example, eight 
