Algae, chiefly Bictyota sp., Udotea oongZutinata , and Gvac-tlaria 

 sp., occurred on this part of the reef but were not nearly as 

 abundant as at Hallandale. The most conspicuous fauna were the 

 soft corals, Eunicea spp. and Pseudoptevogovg'la aoevosa. Several 

 species of hard corals were also common, with Montastvea cavernosa 

 the dominant species. Many of the hard corals in this area appeared 

 diseased or damaged; the causes of these conditions could not be 

 determined. Sponges, represented primarily by Cliona lampa and 

 Haliclona rubens, were more common than on the first reef; although 

 several long-spined urchins were usually visible, they increased in 

 abundance toward the seaward edge of the reef. 



The midpart of the second reef was dominated by a wide 

 variety of octocorals (primarily Eimicea spp.), madreporarians, 

 and sponges. The large star coral, Montastvea cavernosa, the star 

 corals, Stephana coen-La mtchelini. and Bichocoen-ia stokesi-l, and the 

 flower coral, Eusmilia fastigiata, were a few of the more abundant 

 species. The hydrocoral, Mi-ltepora alcioom-is, and the red sponge, 

 Haliclona rubenSj, were also common. Algae were scarce, more so than 

 at equivalent localities off Hallandale Beach. 



Conditions along the outer edge of the second reef [Fig- 9) 

 were very similar to those at Hallandale Beach. The irregular and 

 pitted substrate was invested with numerous soft corals, hard 

 corals, and sponges. One of the most striking similarities was the 

 occurrence of Bictyota sp. which, as at Hallandale, was the only 

 conspicuous algal species present. Biadema antillawm and small 

 motile fauna occurred within the holes and crevices in the reef and 

 among the larger sponges and corals. 



Results from quadrat samples at reef stations off Golden 

 Beach are shown in Table 3. The distribution patterns of organisms 

 are generally similar to those at Hallandale Beach. Although the 

 maximum density of soft corals at Golden Beach (14.0 colonies per 

 square meter at GR-3) was greater than at Hallandale (10.7 colonies 

 per square meter at HR-3) , the same within-transect pattern pre- 

 vailed. The decreased abundance of alcyonarians at the outermost 

 reef stations on both transects may have been due to the increased 

 coverage of stony corals, leaving less available substrate for 

 attachment. 



V. DISCUSSION AND CONCLUSIONS' 



The composition and structure of shallow-water benthic 

 communities are determined by many environmental factors. Sediment 

 type, light intensity, temperature, turbulence, and various bio- 

 logical interactions are among the more important of these factors. 

 In southeastern Florida, man-induced disturbances, such as those 

 resulting from beach nourishment projects, represent an additional 

 influence. 



The most striking pattern in the distribution of sandy- 

 bottom communities within the study area was the great increase in 

 species diversity and density at the offshore stations. More than 



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