flatten in response 

 waves. Instead, the 

 waves is expended on 

 the result that it 



to storm generated 



full force of these 



the structure with 



frequently fails. 



Ultimately, if sea level continues to 

 rise, anything that doesn't migrate 

 shoreward will be destroyed or left at sea 

 like the Morris Island Lighthouse (Figure 

 30)! 



5.3 EFFECTS OF JETTIES ON NEARBY BENTHIC 

 COMMUNITIES 



Knot et al . (1984) sampled the 

 macrobenthic communities of the intertidal 

 and nearshore subtidal environments at 

 Murrells Inlet, South Carolina. This was 

 done during the construction of the jetty 

 and once again 5 years later. They found 

 the infaunal community to be dominated by 

 several species of polychaetes (40% of the 

 species and 60% of the individuals), 

 amphipods, and pelecypods. The presence 

 of the jetty appeared to affect the 



distribution and abundance of only one 

 bivalve and one polychaete. Comparison of 

 species abundance between years and among 

 localities (updrift and downdrift) 

 suggested no widespread impacts 

 attributable to jetty construction. 



5.4 JETTIES AS FISHING SITES 



Recreational fishing is often 

 concentrated around rubble structures 

 (Figure 31) because of the increased 

 numbers of fishes that occur there. 

 Parker et al . (1979) estimated that 

 an artificial reef constructed off 

 Murrells Inlet, SC, increased fish 

 standing stock in that immediate location 

 by a factor of 1,800. Jetties could have 

 similar consequences and often seem to 

 increase angler densities by similar 

 amounts. Figures 32 and 33 show the 

 seasonal pattern of anglers using the 

 jetties at Murrells Inlet, SC, and the 

 species of fishes caught relative to the 

 types for which they were fishing. 



Figure 31 . Large jetties like the one at Murrells Inlet, SC, pictured here, provide favored nearshore fishing sites 

 (photo taken by R. Van Dolah). 



51 



