The primary diet of sheepshead differed from both black sea bass and 
spadefish. Nearly 99% of the food items, by volume, were either mussels 
(Brachtdontes exustus) or algae. As noted previously, the decline in 
subtidal mussel density on the north jetty was attributed largely to 
predation. The stomach content analysis supports this hypothesis since 
B. exustus represented a major component of the sheepshead's diet. Algae, 
which were the most prevalent taxa on the rocks during the latter part of 
the study, represented a major component of stomach contents from 
sheepshead captured in 1981 and 1982. 
Stomachs from three other species were analyzed even though two of 
them, Haemulon seturus and Tautoga onttis, are not generally considered 
to be recreationally important in South Carolina. Stomach contents 
from the one bluestriped grunt captured on the rock indicated that this 
species feeds mostly on algae, amphipods and isopods. The only tautog 
captured had been feeding on isopods, amphipods and decapods found on 
the rocks. Five southern flounder, P. lethostigma, were also captured 
for stomach content analysis but all stomachs were empty. Flounder 
were probably feeding at night around the Murrells Inlet jetties, 
The stomach content analysis documents that the jetty fauna and 
flora are important food sources for the recreationally important fishes. 
Additionally, the results suggest that many of the fishes are minimizing 
competition for these food resources by concentrating on different 
components of the community. Similar divergence in food habits has been 
noted for other communities of sympatric fish species (Ross, 1977). 
V. SUMMARY AND CONCLUSIONS 
1. Rock jetties recently constructed at Murrells Inlet, South Carolina, 
provided a valuable opportunity to study colonization and community 
development patterns of biota on rocky substrata. Previous studies of 
this type have been very limited along the southeastern coast of the 
United States. 
2. Construction began on the Murrells Inlet Navigation Project during 
the autumn of 1977 in order to provide a stabilized entrance channel 
to the ocean. The seaward terminus of the north jetty was completed 
by December 1978, and annual sampling was initiated at four stations on 
that jetty during the summer of 1979. The seaward terminus of the south 
jetty was completed by March 1980. Sampling began at four stations on 
that jetty in the spring of the same year and continued at quarterly 
intervals for the first year. After that, sampling was restricted to 
once a year during summer, as on the north jetty. The north jetty was 
studied over a four-year period, whereas the south jetty was studied for 
a three-year period. Two of the stations on each jetty were on the wave- 
exposed side and two others were located on the protected channel side. 
3. At each station, sessile biota was assessed at 7 or 8 levels, 
depending on station location. Intertidal levels were located at 0.5-m 
intervals from mean low water (MLW) to 2.5 m above MLW; subtidal levels 
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