Keauhou Bay have failed to recover after 30 years because of pollution, light 

 limitation, sedimentation, 'and possibly competition from other benthic organisms, 



In summary, it must be recognized that coral recovery is generally very 

 slow and sometimes never occurs. 



4. Sea Turtles . 



The recovery of sea turtles will depend on the severity of the dredging 

 impact. Hibernating sea turtles have been captured or killed by dredging 

 (U.S. Army Engineer District, Jacksonville, 1981). However, normally turtles 

 should react similarly to other motile animals and return to the area when 

 dredging ceases. 



XI . RECOMMENDATIONS 



The following recommendations are based on CERC-sponsored research and 

 other literature. Physical, chemica] , and biological conditions tend to vary 

 from place to place; therefore, recommended procedures may not apply to all 

 situations. However, for the benefit of the coastal manager these recommen- 

 dations should be considered guidelines and used cautiously. 



1. Beach Nourishment . 



a. Biotic Surveys . Several investigators have suggested that animal 

 communities be surveyed before, during, and after dredging and nourishment 

 (Ingle, 1952; Thompson, 1973; Spadoni, 1978; Courtenay, Hartig, and Loisel, 

 1980; Marsh, et al., 1980). Such studies can be both qualitative and extensive 

 depending on the intent of the study and resources available. This common 

 survey approach is the least expensive and usually contributes the most toward 

 avoiding unnecessary damage to valuable marine resources. As an absolute 

 minimum a preproject base-line survey should be sponsored to identify and 

 locate sensitive ecological resources, e.g., coral reefs, clam beds, and sea- 

 grass, in order to avoid these sensitive areas. See Rurme, Yancey, and Pullen 

 (1979) for methodology and cost for such studies. 



b. Optimum Time for Operation . Most CERC studies and others indicate 

 that the best time biologically for beach nourishment and dredging is during 

 the winter (Saloman, 1974; Oliver and Slattery, 1976; Reilly and Bellis, 1978; 

 U.S. Army, Corps of Engineers, 1979). This is because the spawning season for 

 most nearshore and beach fauna occurs between the spring and fall. The hainn- 

 ful effects of engineering activities are usually minimum during the winter, 

 and larval recruitment is not severely affected. Spadoni (1978) feels that 

 summer would be better since the ocean is calmer during this period and allows 

 rapid settlement of suspended sediments. However, based on CERC's experience 

 and a review of the literature, construction during the winter season seems to 

 be the best choice biologically. There would be a minimal effect on the adult 

 and developmental stages of most nearshore and beach animals, and then fish 

 and shellfish are less concentrated in the shallow beach zone during the winter 

 season. It is, however, still necessary to determine if sensitive nonmotile 

 resources are in the area during this period. 



c. Composition of Nourishment Material . The composition of indigenous 

 sediment at the deposition site should closely match with the dredged material 



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