most of the low hammocks surveyed. 

 They are: red mangrove ( Rhizophora 

 mangle ) , buttonwood ( Conocarpus 

 erecta j , poison wood ( Metopium 



toxiferum ) , Spanish stopper ( Eugenia 

 foetida ) , white stopper ( Eugenia 

 axillaris ) , pale lid- flower ( Caly - 

 ptranthes pallens) , cabbage palm 

 ( Sabal palmetto ) , red bay ( Per sea 

 borbonia ) , and West-Indian mahogany 

 ( Swietenia mahogani ) . 



"The understory vegetation is 

 relatively rich, but the abundances 

 of each species vary considerably 

 between stands. The most typical 

 species are: myrsine ( My r sine 



floridana ) , chicken grape ( Vitis 

 rotundifolia , poison ivy ( Toxico- 

 dendron radicans) , swamp fern 

 ( blechnum serrulatum ) , and potato 

 tree ( 5 planum verba sci ; folium ) . Sev- 

 eral epiphytes are common including 

 reflexed wild pine ( Tillandsia 

 balbisiana ) , banded wild pine 

 ( T. flexuosa ) , soft-leaved wild pine 

 ( T. valenzuelana ) , and giant wild 

 pine ( T. utriculata ) . Other epiphy- 

 tes include the following: yellow 

 catopsis ( Catopsis berteroniana ) , 

 butterfly orchid ( Encyclia tampen- 

 sis ) , worm vine ( Vanilla barbel- 

 lata ) , butterfly orchid ( Encyclia 

 boothiana ) , resurrection fern ( Poly- 

 podium polypodioides) , and serpent 

 fern ( Phlebodium aureum ) . " 



7.23 OPEN WATERS 



Unlike the brackish wetlands 

 environment, the open water environ- 

 ment is less amenable to clearly 

 defined wildlife habitats or vege- 

 tational zonations. Daily and 



seasonal variations in salinity and 

 temperature cause considerable flux 

 in vegetation distributions. 



nance is replaced by the fresh water 

 marsh and slough flora of the Ever- 

 glades. Batophora oerstedi , another 

 alga, may also be found in the 

 transition zone in association with 

 rock outcroppings, or wood surfaces 

 upon which to attach. Chara and 

 Batophora apparently prefer a fairly 

 low salinity range (0-10 ppt) and 

 thus in general achieve their great- 

 est areal coverage in the winter 

 (November through February). They 

 have been observed dominating a 

 considerable portion of Whitewater 

 Bay during these months. Chara has 

 also been observed surviving in 

 waters approaching 30 ppt while 

 Batophora has been reported from 

 hypersaline Florida Bay (Hudson et 

 al. 1970). Widgeon grass ( Ruppia 

 maritima ) reaches its greatest den- 

 sities during low salinity periods 

 in Coot and Whitewater Bays. 



Intermediate to high salinities 

 favor the invasion of the bays and 

 estuaries by a different suite of 

 vegetation dominants. In Whitewater 

 Bay, three species of macroalgae 

 reportedly occur in large quantities 

 during higher salinities (Tabb et 

 al. 1962). They are: Acetabuleria 

 crenulata , Caulerpa verticillata , 

 and Udotea wilsoni . Invasion of the 

 extensive Udotea beds by the red 

 algae Dasya pedicellata and Gracila- 

 ria confervoides were observed when- 

 ever salinities rose above 20-25 

 ppt. The latter are epiphytic on 

 Udotea or attached to coarser 

 shell gravel. Shoalgrass ( Halodule 

 wriqhtii ) , which generally replaced 

 the Ruppia in Coot and Whitewater 

 Bays at higher salinities, all but 

 disappeared from the area after the 

 opening of the Buttonwood canal in 

 1957 (Tabb et al. 1962). 



Tabb et al. (1962) report that 

 the dominant aquatic plant of the 

 extensive salt/fresh transition zone 

 is the macroalga Chara hornemanni . 

 Upstream of this zone Chara domi- 



Figure 50 summarizes the gener- 

 al trends observed between salinity, 

 vegetation, and bottom type in 

 Whitewater and Coot Bays. Unfortu- 

 nately this work was performed in 



149 



