The abundance of fauna and the complexity of the reef surface 

 were greatest near the offshore edge of the second reef. Stony 

 corals were numerous at this location, with Montastvea oaxiemosa 

 the dominant species. Other common species included the clubbed- 

 finger coral, the common brain coral (Diploria strigosd) , and the 

 rose coral {Manicina areolata) . Octocorallians were very con- 

 spicuous, especially Euni-oea spp.; Pseudopterog'orgi.a acerosa and 

 the common sea fan (Gorgonia ventalina) were also among the more 

 abundant species. Sponges were well represented, with Haliolona 

 vubens by far the most common species; the vase sponge {Irainia 

 oampand] , the chicken liver sponge {Chrondrilla nueuld) , and 

 numerous other species were also present. The long-spined sea 

 urchin (Diadema antillarum) was more abundant at this locality 

 than at any other reef station. Less conspicuous, but also common, 

 was the pencil urchin (Euoidaris tribuloides) . Spiney lobsters 

 were often observed beneath the outer ledge. Algae were notably 

 scarce at the outer edge of the second reef, with the exception of 

 Diotyota sp. 



Results from quadrat samples of the Hallandale Beach reef 

 stations are shown in Table 3. For each station, the total number 

 of specimens of each of the more abundant or conspicuous faunal 

 species occurring in three 1.0 square meter quadrats is indicated. 

 The relative abundance of algal species is also shown. Despite the 

 obvious difficulties involved in quantifying colonial organisms, 

 each species of which may vary greatly in size or area coverage, 

 the quadrat samples substantiate the more subjective visual impres- 

 sions of each part of the reefs. The scarcity of fauna on the 

 first reef, the decrease in the abundance of algae at greater 

 depths, and the increased density and diversity of sponges, 

 alcyonarians, and hard corals toward the middle and outer parts 

 of the second reef, are all apparent from these data. The density 

 of soft corals, based on quadrat samples, was greater in the 

 interior of the second reef (HR-3) than at the other stations. The 

 average density at HR-3 was 10.7 colonies (all species) per square 

 meter, compared to 3.7 colonies per square meter at HR-1 and 6.0 

 colonies per square meter at both HR-2 and HR-4. 



b. Golden Beach . As at Hallandale Beach, the first reef 

 off Golden Beach was populated mostly by clumps of attached algae, 

 including primarily the rhodophytes, Gvacilavia sp. and Corynomorpha 

 alavata. Diotyota sp. and Udotea conglutinata were among several 

 other fairly common algae. 



Animal life on the first reef was poorly represented. A few 

 widely scattered alcyonarians, including Evnieea sucoinea and 

 Pseudopterogovg-ia acerosa, and an occasional small madreporarian 

 were the most conspicuous faunal elements. A few reddish-orange 

 patches of the boring sponge (Cliona lampa) occurred on the lime- 

 stone surface. The only motile fauna noted was an occasional urchin 

 {Lyteohinus variegatus) . 



Along the inshore edge of the second reef off Golden Beach, 

 the outcrop had a more solid, discrete structure than at Hallandale 

 where numerous patches of loose rubble formed a transitional zone. 



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