VIII. FAUNAL RECOVERY OF NOURISHMENT SITES 



The time required for faunal recovery following beach nourishment varies 

 and is difficult to predict because of natural variations in biotic and abiotic 

 factors. Natural perturbances (storms) and normal population fluctuations 

 (seasonal and nonseasonal) can cause abrupt changes in physical, chemical, and 

 biological conditions of an area. These natural fluctuations in undisturbed 

 coastal environments and their biotic populations can be so great that it is 

 difficult to detect effects of human activities or recovery time of a biotic 

 system (Maurer, et al., 1979). Studies applicable to fauna recovery should be 

 carefully designed and extend at least 2 or more years for their seasonal and 

 nonseasonal fluctuations to be adequately considered in analyzing the impact of 

 a manmade disturbance. 



1. Benthic Communities . 



Recovery of macrobenthic animals varies and differs from one site to 

 another. Reilly and Bellis (1978) and Parr, Diener, and Lacy (1978) noted that 

 when nourishment ceases, the recovery of the macrofauna is rapid and complete 

 recovery might occur within one or two seasons. Saloman (197A), Taylor Biologi- 

 cal Company (1978), Marsh, et al. (1980), and Culter and Mahadevan (1982) also 

 support the view that macrofauna will recover rapidly after ecological pertur- 

 bations. Tropical Biological Industries (1979) predicted the normal macro- 

 faunal recovery to be about 5 to 6 weeks following beach nourishment . Recovery 

 will depend on the season of the year of the nourishment operation and the 

 recruitment of larval fauna. The ability of the macrofauna to recover rapidly 

 is due to (a) their short life cycles, (b) their fast reproductive potential, 

 and (c) the recruitment of plankton larvae and motile macrofauna from nearby 

 unaffected areas. Opportunistic species are the first to invade an area, 

 followed by the establishment of a more stable population. 



The adjustment of macrobenthic populations to perturbation is a natural 

 event. Perturbations from storms cause faunal changes on the beach similar to 

 manmade perturbations. Saloman and Naughton (1977) observed the effects of 

 Hurricane Eloise at Panama City Beach, Florida, where severe beach erosion and 

 property damage resulted. The beach benthic communities were modified. Oceanic 

 species were washed inshore increasing species diversity along the beach. 

 Simon and Dauer (1977) studied faunal damage caused by red tide at Tampa Bay, 

 Florida. Benthic animal populations were destroyed, but their populations 

 recolonized after about the 11th month. In these studies recovery rate differed 

 from one taxon to another. Therefore, care should be taken when using a single 

 taxon to interpret an environmental perturbation. 



Meiofauna recover very slowly from a major disturbance, perhaps due to their 

 slow reproduction, limited ability to migrate, and their highly specialized 

 adaptations to a restricted environment. Pequegnat (1975) and Rogers (1976) 

 noted the slow recovery and lack of resiliency in meiobenthic organisms. Rogers 

 and Darnell (1973) noted that meiobenthic populations had not completely re- 

 covered, even 18 years after a disturbance in a Texas estuary. However, 

 Sherman and Coull (1980) found the recovery rapid (after one tidal cycle) for a 

 minor disturbance. 



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