Imperial Beach, California. However, the dusky jawfish {Opistogyiathus 

 whitehursti.) , a burrowing species with a limited power of mobility and a 

 requirement for a certain sand grain size, was displaced by fine sediments on 

 the Florida east coast (Courtenay, Hartig, and Loisel, 1980). 



The loss of a food source by burial of nourishment sediments will have some 

 effect on motile populations, but this has not been demonstrated to be of major 

 significance. However, there has been evidence that nourishment may benefit 

 fish by suspending food material (Courtenay, et al., 1972) and associated tur- 

 bidities may provide temporary protection from predators (Harper, 1973) . Fishes 

 have also been attracted to dredging operations in Florida (Ingle, 1952) and 

 Louisiana (Viosca, 1958) and sand mining operations in Hawaii (Maragos, et al . , 

 1977). 



4. Effects on Corals . 



Corals are sensitive to covering by fine sediments. The hard corals are 

 more sensitive than the soft corals because they are unable to cleanse them- 

 selves of heavy sediment loads and are easily smothered. The soft corals are 

 better adapted for survival in the nearshore areas subject to beach nourishment. 



Coral damage as a result of beach nourishment is usually caused by exces- 

 sive sedimentation and by direct physical damage to a reef. Sedimentation 

 may inhibit the food-acquiring capability of polyps, eventually killing the 

 coral, and inhibit protosynthesis of symbiotic green algae (Zooxanthellae) 

 (Goldberg, 1970; Courtenay, et al., 1972). Both are essential for the survival 

 of the coral. 



On the other hand, studies have shown that coral reefs are not totally 

 fragile and that they can withstand some sedimentation. Courtenay, et al. 

 (1974) studied the effects of beach nourishment on nearshore reefs at 

 Hallandale Beach, Florida. They noted that the reefs sustained damage caused 

 by fine materials eroding from the nourished beach. Seven years later 

 Courtenay, Hartig, and Loisel (1980) and Marsh, et al. (1980) resurveyed the 

 reefs and found no evidence of major reef damage. 



5. Effects on Sea Turtles . 



Sea turtle nesting and beach nourishment operations conflict in many coastal 

 areas, particularly along the Florida coast (Fig. 7). Beach nourishment may 

 inhibit or reduce turtle nesting and hatching success by altering their habitat 

 (Mann, 1977; Fletemeyer, 1978, 1979, 1980). Hendrickson and Balasingham (1966) 

 found that the sand particle size affected nest selection by leatherback turtles 

 {Dermoohetys oovlacea) . Fletemeyer (1978, 1979, 1980) also determined com- 

 paction of sand to be important for nest selection by Loggerhead turtles. The 

 same author reported a higher number of "false crawls" on two of the six nour- 

 ished beaches in Florida. The effects of beach nourishment on sea turtles are 

 inconclusive due to lack of adequate data, but the studies do indicate caution 

 should be taken in nourishing turtle-nesting beaches. If it is determined that 

 a project will affect sea turtles, U.S. Fish and Wildlife Service, National 

 Marine Fisheries Service, and turtle experts should be consulted to develop a 

 plan that will minimize the impact of beach nourisliment . Adverse effects may 

 also be avoided by the proper timing of the operation to not conflict with 

 turtle nesting during the spring and summer (April to September) . 



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