CHAPTER 8 

 FLORIDA BAY AND MANGROVE ISLANDS 



8.1 PREVIOUS LITERATURE 

 REVIEWS AND SYNTHESES 



In addition to the recent work 

 of Odum et al. (1982), Zieman (1982) 

 has summarized the existing litera- 

 ture on another major ecological 

 component of the south Florida coast 

 in a document entitled A Community 

 Profile: The Ecology of the Sea - 

 grass Community in South Florida . 

 In this document the author draws, 

 in part, from the same information 

 as the present report. As in the 

 mangrove zone, it would be redundant 

 for us to summarize the same infor- 

 mation. Consequently the following 

 discussion focuses on ecological 

 elements not included in the above 

 documents and on information which 

 is specific to the study area. For 

 a complete review of seagrass ecol- 

 ogy, the Zieman (1982) document is 

 strongly recommended. 



8.2 HABITAT ZONATION 



As described previously, Flor- 

 ida Bay is a shallow body of water 

 characterized by an anastomosing 

 series of carbonate mud banks, or 

 shoals. These shoals are quite 



often covered with a rich growth of 

 sea grasses, primarily turtle grass 

 ( Thalassia testudinum ) with some 

 shoal grass ( Halodule wriqhtii ) and 

 manatee grass ( Syrinqodium fili- 

 forme ) (Hudson et al. 1970). The 

 pinnacles of the shoals are usually 

 vegetated by mangroves and other 

 salt tolerant shrubs and herbs such 

 as saltwort ( Batis maritima ), glass- 

 wort ( Salicornia perennis ), sea ox- 

 eye ( Borrichia frutescens ), and key 

 grass ( Monanthochloe littoralis ) 

 (Davis 1940). These "flats" also 

 support a healthy growth of calcar- 

 eous blue-green algae. The shoals 



generally surround deeper, open 

 water areas (lakes) which are cover- 

 ed by a relatively thin veneer of 

 lime muds over a rock hardened lime- 

 stone substrate. 



Although no one has documented 

 the actual composition and distribu- 

 tion of submerged vegetation in 

 Florida Bay, numerous species of 

 green, red, and blue-green algae are 

 known to inhabit the area (Ginsburg 

 1956, Stockman et al. 1967, Ginsburg 

 et al. 1972, Woelkerling 1976). 

 Most prominent among these are the 

 green algae Penicillus sp., Rhipoce- 

 phelus sp. , Udotea sp. , Halimeda sp. 

 and Acetabularia sp. Blue-greens, 

 particularly Schizothrix and Oscil- 

 latoria are most often associated 

 with intertidal flats and extreme 

 shallows (Ginsburg et al. 1972). 

 The red alga Molebesia sp. is re- 

 ported as often virtually covering 

 the blades of Thalassia with a 

 thin fragile crust (Stockman et al. 

 1967). 



Tabb et al. (1962) describe two 

 general growth forms of Thalassia in 

 northern Florida Bay; (1) a stunted 

 and sparse growth of plants 31 to 91 

 cm (1 to 3 feet) tall in the shal- 

 lows just off of Flamingo in highly 

 turbid waters; and (2) tall dense 

 stands east of Flamingo and south of 

 Cape Sable in the Sandy Key Basin. 

 Unfortunately, these are the only 

 two areas they studied. Assuming 

 that turbidity (and probably hyper- 

 salinity) are at least in part re- 

 sponsible for the stunted growth, it 

 is likely that much of the interior 

 bay would exhibit a similar mixture 

 of forms. 



In lieu of vegetationally de- 

 fined habitats, Turney and Perkins 



165 



