and reported considerable damage to the reefs immediately adjacent 

 to the borrow site, although reefs closer inshore appeared to be 

 relatively unaffected. Damage to the offshore reefs apparently 

 resulted primarily from scouring and abrasion by dredging equipment. 



The present study was designed as a quantitative post- 

 nourishment assessment of benthic fauna in the same area surveyed 

 by Courtenay, et al. (1974) at Hallandale Beach (Fig. 1). 



Another beach restoration project began at Hallandale Beach 

 in September 1979. The results of the present study will provide 

 prenourishment data for use in assessing the impact Of this second 

 project. 



11. DESCRIPTION OF AREA 



The shelf topography off southeastern Florida is character- 

 ized by a linear series of steplike sandflats separated by elevated 

 limestone outcrops which generally parallel the shoreline. These 

 outcrops, or "reefs," are of Pleistocene origin (Duane and Meisbur- 

 ger, 1969) and support a great variety of sponges, alcyonarians, 

 and stony corals. The sediments within the flats are white to 

 gray calcareous sands and gravel consisting primarily of algal 

 plates, shell fragments, foraminiferans, bits of coral skeleton, 

 and other calcareous debris. The acid-soluble component of this 

 sand is generally more than 80 percent. 



In the immediate study area, off southern Broward County 

 (Fig. 1) , the narrow shoreface slope levels out at depths of 3 to 

 4 meters to form the inner flat. The shoreface slope is quite 

 variable in extent and configuration, being highly influenced by 

 the effects of waves, currents, and littoral sand supply. 



Approximately 50 to 60 meters from shore, the inner sandflat 

 delimited by the first reef (Figs. 1 and 2), a low profile outcrop 

 averaging about 50 meters in width. Much of the reef is often 

 covered with a thin layer of sand, leaving only scattered patches 

 of exposed limestone. The most conspicuous feature of the first 

 reef is the scattered tufts of attached algae. Animal life is 

 relatively scarce, represented primarily by a few sparsely distri- 

 buted octocorals and reddish patches of boring sponge (Cliona 

 lampa) . 



Seaward of the first reef is a sandy plateau averaging about 

 50 meters in width. This plateau terminates at the inshore edge of 

 the second reef, a broad, rocky platform about 450 to 500 meters in 

 width and occurring at depths of 7 to 8 meters. The second reef 

 was more conspicuous than the first reef, with greater relief, more 

 crevices and outcrops, and a large number of sea fans, sea whips, 

 stony corals, sponges, and other marine invertebrates, as well as 

 a great diversity of fishes. At the jagged outer edge of the second 

 reef was a pronounced ledge, averaging about 1 meter in height, but 

 reaching heights of 2 or more meters in some localities. Underwater 

 visibility was usually excellent, and animal life was abundant along 

 the outer ledge of the reef (Courtenay, Hartig, and Loisel, 1980). 



