2. Motile Animals . 



Most long-term studies have shovzn that moderate to complete recovery of 

 motile animals will occur within less than a year, unless a sensitive resource 

 is involved, e.g., coral reefs. Courtenay, et al. (1972, 1980), Parr, Diener, 

 and Lacy (1978), Reilly and Bellis (1978), and Holland, Chambers, and 

 Blackman (1980) described motile fauna recovery following beach nourishment. 

 Based on their studies it appears that motile fauna are generally not affected 

 severely by beach nourishment. Studies have shown that motile animals generally 

 leave an area of perturbance temporarily, but return when the disturbance ceases. 

 Oliver, et al . (1977) observed that demersal fish moved into a disturbed area 

 within the first day after disturbance. Courtenay, Hartig, and Loisel (1980) 

 noted that lobsters, crabs, shrimp, and fish left a disturbed area, but 

 reappeared A months after the disturbance ceased. The motile animals which 

 have a stringent requirement for biological activities, i.e., habitat require- 

 ment or food source, are most likely to be affected. Sherk, O'Connor, and 

 Neumann (1974) found that demersal fish are more tolerant to suspended solids 

 and filter-feeding fish are least tolerant. Thus, based on these studies and 

 observations during CERC studies in other coastal areas, it is concluded that 

 fish fauna are usually not severely impacted by beach nourishment activities 

 and will rapidly return to the impacted area after the disturbance ceases. An 

 exception to this generalization would be species with a special habitat 

 requirement or food source that is destroyed in the disturbance, e.g., the 

 dusky jawfish on the Florida Atlantic coast. 



3. Corals . 



The recovery time for corals is directly proportional to the extent of 

 initial reef damage. A reef that is badly torn and covered heavily with fine 

 sediment, which kills the existing corals, may take a long time or may never 

 recover. 



Courtenay, et al. (1972, 1974) documented the initial effects of beach 

 nourishment on corals in Florida. Reef-building corals exhibited damage from 

 turbidity and sediment. In later surveys of the same area, Courtenay, Hartig, 

 and Loisel (1980) and Marsh, et al. (1980) found maximum abundance and diver- 

 sity of reef biota and corals after the nourishment area was left undisturbed 

 for 7 years. These studies demonstrated that corals can recover from a dis- 

 turbance if the damage is not too great. However, Bak (1978) concluded that 

 recovery is generally slow and sometimes never occurs. 



4. Sea Turtles . 



Little information is available on the sea turtle's use of a beach following 

 nourishment. Mann (1977) and Fletemeyer (1980) reported that sea turtles may 

 be affected adversely by artificial changes in the beach substrate where they 

 nest. 



IX. EFFECTS OF BORROWING 



The most evident effect of offshore or nearshore borrowing is the mechanical 

 disturbance of the substrate and subsequently the redeposition of suspended 

 sediment and turbidity. Since varied assemblages of organisms reside in these 



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